COLUMBIA LIBRARIES OFFSITE HEALTH SCIENCES STANDARD / s^ ^cfjool of Bental anb <0ral ^urgerj* 3^eferente Hibrarp LOCAL ANESTHESIA LOCAL ANESTHESIA DR. ARTHUR SCHLESINGER (BERLIN) TRANSLATED BY F. S. ARNOLD, B.A., M.B., B.Ch. (Oxon.) ILLUSTRATED m NEW YORK REBMAN COMPANY Herald Square Building 141-145 West 36TH Street Printed in England PEEFACE The study of local anaesthesia has made such great progress recently, and has led to so great an improvement and perfecting of methods, that it seems desirable that it should be still more widely employed by medical practitioners than has hitherto been the case. Only in the last year or two has it begun to figure at all frequently as an item of any importance in the clinical curriculum, a change which will be, I think, of material advan- tage to the present generation of students. ^ The chief aim of this book is to enable those who have no opportunity to gain acquaintance with the various methods by observing them in actual practice, to perfect themselves in technique by proceeding gradually from the simpler to the more difficult tasks. In the second place, I have endeavoured to describe, in accordance with the present state of our knowledge and for the benefit of specialists, the best methods of dealing with those more difficult tasks. Comparatively little space has been given to expositions of theory. These are, however, so vi PREFACE important for a right understanding of the subject that due consideration should always be given to them, especially as, owing to the very rapid development of our subject, many divergences of opinion have arisen. I have avoided detailed references to the literature, but have everywhere named the more important authorities. As regards technique, I have throughout en- deavoured to put before my readers what I have found by experience to be the simplest and most practical methods. Where new" and as yet un- proved methods are cited, the fact is always made clear in the text. I have to render cordial thanks to Privatdozent Dr. Haike and to Dr. Fehr, Surgeon to the Yirchow Hospital ; to the former for assistance in the preparation of the section on aural and nasal operations, and to the latter for similar help in dealing with operations on the eye. THE AUTHOR. CONTENTS PAGE PREFACE . . . . . .V CHAPTER I. HISTORICAL SURVEY .... 1 II. PHYSICAL PRINCIPLES . . . .13 III. LOCAL ANESTHETICS . . . .18 COCAIN AND ITS SUBSTITUTES . . .19 SUBSTANCES WHICH PRODUCE AN ANESTHETIC EFFECT BY MEANS OF COLD . .19 IV. ADJUVANTS IN LOCAL ANESTHESIA . . 37 1. COLD . . . . .38 2. ANEMIA : PRODUCED — . . .40 (a) BY CONSTRICTION . . .40 (5) BY INFILTRATION (SCHLEICH). . 41 (c) BY SUPRARENAL PREPARATIONS . 42 V. METHODS OF LOCAL ANESTHESIA AND THEIR AP- PLICATION . . . .52 1. ANESTHESIA PRODUCED BY COLD . . 52 2. ANESTHETIZATION OF SURFACES . .54 3. SCHLEICH'S INFILTRATION ANESTHESIA . 56 4. ANESTHESIA BY INTERRUPTION OF SENSORY CONDUCTION ("NERVE BLOCKING ") . 63 5. VENOUS ANESTHESIA . . .68 ARTERIAL ANESTHESIA . . .74 vii Vlll CONTENTS CHAPTER VI. GENERAL TECHNIQUE . . . . VII. METHODS FOR ANESTHETIZING THE SKIN AND THE DIFFERENT TISSUES — PROCEDURE IN CERTAIN DISEASED CONDITIONS— CIRCULAR ANALGESIA VIII. OPERATIONS ON THE HEAD 1. OPERATIONS ON THE SCALP AND FOREHEAD 2. OPERATIONS ON THE FACE . 3. OPERATIONS ON THE EAR . OPERATIONS ON THE NASAL AND ORAL CAVITIES .... OPERATIONS ON THE EYE . IX. OPERATIONS ON THE CERVICAL REGION . X. OPERATIONS ON THE THORAX XI. OPERATIONS ON THE EXTREMITIES XII. ABDOMINAL OPERATIONS . nERNIA OPERATIONS . XIII. O.'ERATIONS ON THE ANAL REGION AND THE GENITO-URINARY TRACT PAGE 75 93 105 105 110 111 119 123 145 153 157 175 184 193 INDEX 203 LOCAL ANiESTHESIA CHAPTEE I HISTORICAL SURVEY The endeavour to render operations painless by inducing local ansesthesia is almost as old as medicine itself. From the most ancient times physicians have, in addition to their attempts to carry out operations painlessly by some method of dulling the sensor ium, endeavoured also by some locally acting agent to secure anaesthesia or the actual site of operation. The different ways in which this end was sought to be attained may here be briefly reviewed. Leaving out of account the experiments men- tioned by ancient writers, with crocodile fat, dried and powdered crocodile skin, friction with vinegar and stone of Memphis, and so on, we may regard as the earliest scientific method — 1. The Production of Aiiwsthesia hy Compression of Nerves. — In very early times, and later among the Arabs, the method of nerve compression by liga- 2 LOCAL ANESTHESIA turing the extremities was practised with a view to the production of local anaesthesia. Since then the method has been again and again "re-dis- covered," only to be again abandoned on account of its imperfections. At the beginning of the nineteenth century it was, according to Desault, in frequent use. Quite recently the method has been once more " discovered " by Kofmann. While, however, the earlier authorities regarded the nerve compression brought about by ligaturing the extremities as the anaesthesia-producing agent, Kofmann held that the anaesthesia was caused by the bloodless condition of the limb due to the ligature. Braun's experiments have proved finally that ligature owes such power as it possesses to diminish pain solely to the compression of nerves caused by it. 2. Cold as an anaesthetic agent was first em- ployed in the sixteenth century by Marcus Aurelius Severinus, who simply placed pieces of ice upon the part to be anaesthetized. Much later the anaesthetic action of cold was again learnt in the Napoleonic campaigns in Russia [Larrey), when, as for instance after the Battle of Eylau, it was found that limbs benumbed by cold could be ampu- tated without pain. After this Hunter, and later (1849) Arnott, employed freezing mixtures for the production of local anaesthesia. A few years later, again, sulphuric ether was employed by Bochet, HISTORICAL SURVEY 3 the method at first adopted being to allow the ether to drop slowly upon the skin and evaporate. It was not, however, until 1866 that Richardson furnished, in his well-known and still widely used ether spray apparatus, a really practical means for the utilization of the volatile properties of ether. The substances which have since that time been introduced as substitutes for ether, to be applied by means of the spray apparatus, such as brom- ethyl, ethylene chloride, etc., have not all succeeded in securing any wide adoption. The introduction of ethyl chloride constituted the first notable ad- vance, inasmuch as its applicability was indepen- dent of the surrounding temperature. At all ordinary room temperatures the chloride of ethyl is gaseous, and can only be kept in the liquid state under pressure. The time required to freeze the skin is, by the use of ethyl chloride, notably diminished. The newer substances of still lower boiling-point than ethyl chloride {methyl chloride, ancesthyl, metethyl, koryl, etc.) have not been much used, the danger of injury to the tissues increasing with the rapidity of action of the evaporating agent. Equally little practical success has attended attempts to employ ethyl chloride or ether to act upon deep structures such as nerve-trunks {Boss- bach, Sc heller, von Hacker). 4 LOCAL ANESTHESIA 3. As regards other purely physical methods, it may be stated, merely as a matter of historical interest, that in the 'fifties of the last century the electric current was warmly extolled as a local anaesthetic agent, and that the claims made for it proved to be quite unjustified. It is possible that results of practical utility may eventually be attained by the use of rhythmic intermittent currents (the so-called Le Due's currents). Re- peated experiments by the author have had nega- tive results. At the same time, the fact that with these currents one can obtain at any rate a diminution of sensibility, e.g., in the finger (one electrode on the median nerve and the other around the base of the finger), shows that the prospect of some further practical advance in this direction is not to be summarily dis- missed. Other physical conditions — osmotic differences, drying or infiltration of tissues, etc. — play, as we shall see, a certain r61e as auxiliaries in the pro- duction of local anaesthesia. 4. Finally, attempts to produce local anaesthesia by chemical means can also be traced back to ancient times. In this connection the impetus to investigation has almost always been given by the idea that substances which produce a general deadening of sensibility must, if applied to some special part, exert there also a sedative influence. HISTORICAL SURVEY 5 Thus the Egyptians, the Greeks, and, later, the Romans employed the poppy, Indian hemp, hen- bane, mandrake-root, and mandragora, as local anaesthetics. The same conception governed the practice of the Middle Ages. Plasters and poultices containing the substances named were applied to the site of operation by medieval physicians, while the ancients generally employed sponges soaked in the juice of the selected plant. As late as the middle of the nineteenth century Bouisson stated that he could produce anaesthesia of a toe by applying opium compresses. When the general anaesthetic properties of ether and chloroform were discovered, these substances also came into use for the production of local anaesthesia. Richardson and Aran believed that local anaesthesia, as well as general narcosis, depended on abstraction of water. Later, again, Tiirck and Scheif employed local applications of chloroform, solutions of morphine salts, etc., for the anaesthetization, for instance, of the laryngeal mucous membrane. All these experiments were quite without practical result. The ever new recommendations, however, of substances and methods show how great is the power of sugges- tion in the whole matter. The recommendations are, of course, made for the most part in good faith, but the optimism of operators and variations in the degree of sensibility to pain in their patients 6 LOCAL ANAESTHESIA have been very fruitful sources of fallacy in these experiments. Again, after the discovery of the method of hypodermic injection by Wood in 1853, the local anaesthetic power of morphia and chloroform was tested by this method, in the latter case with the result that the pain of the injection often greatly exceeded that of the operation itself Of other sedative substances and methods which have been experimented with and recommended, mention may be made of hydrocyanic acid {Simpson), carbonic acid externally applied [Perci- val, 1772), and saponin hypodermically injected (Pelikan). The question of the production of local insensi- bility to pain acquired an altogether greater practical importance with the commencement of our knowledge of the local ansesthetic pro]3erties of cocain. Leaves of the coca-plant were brought to Germany by Scherzer from South America, where their partly stimulating and tonic and partly sedative effects had long been known. In several German laboratories investigations were made with a view to the discovery of the true active principle of the plant. At first it was thought that this had been discovered in a body to which the name erythroxylin was given. Later, however, the claims of this body were entirely thrust aside in favour of those of a substance dis- HISTOEICAL SURVEY 7 covered in Woehler's laboratory by Niemann and Lossen in 1860, and named by them cocain. Twenty years elapsed before the knowledge of the anaesthetic properties of the substance spread sufficiently widely in the medical profession to lead to the resolve to test its applicability to operative surgery. Its results in ophthalmic operations were first reported on in 1884 by Roller, and soon after this followed its use as a locally-applied anaesthetic in operations on the nose and larynx. In 1885 the first monographs on the use of cocain hypodermically in surgical operations ap- peared almost simultaneously in Germany, the United States, and Austria {Landerer, Corning, Woelfler). The most important of these papers is that of Corning, which establishes two signifi- cant facts : (1) The heightened effect of cocain in tissues emptied of blood, and the consequent possibility of obtaining satisfactory results by the injection of very dilute solutions ; (2) the possi- bility of interrupting conduction in sensory nerves by cocain injections, an observation which formed the foundation of the method of conduction- ancestliesia, later to become so fruitful in good results. In general, the method adopted in these early times of cocain anaesthesia was to inject certain quantities of 1 to 5 per cent, solutions in the 8 LOCAL ANESTHESIA neighbourhood of the site of operation and to wait for their diffusion. It was the French surgeon, E-eclus, who w^as the first — in the late eighties of last century — to make any extended use of cocain injections for the production of local ana3sthesia. He employed at first 5 per cent., later 1 per cent, and J per cent, solutions, and performed with their aid a very large number of operations on the genito-urinary organs and the anus. We cannot, in the light of our present knowledge, assent when he describes his methods as free from risk. His maximal dose of 0'2 gramme (3*08 grains) injected in 1 per cent, solution is undoubtedly much too large — so dangerous, indeed, in my opinion, that one is almost forced to conclude that the preparations employed by him were different from those used nowadays. The credit of devising a technique satisfying the first demand one is entitled to make of any method for producing local anaesthesia — namely, that it shall be safe and thus freely utilizable — belongs undoubtedly to the Berlin surgeon, Schleich. For a long time past a Schleich-Reclus " infiltration anaesthesia " has been spoken of. It is certain, however, that the method to which Schleich gave that name, with its production of a local oedema and its small dose of cocain, differs in principle from any that preceded it. The HISTORICAL SURVEY 9 method of rendering the skin itself insensitive by injecting in such a manner as to form wheals { Qaaddel ) wSiS desQrihed by Roberts before Eeclus or Schleich wrote on the subject. Schleich's discovery was greeted with much scepticism when first demonstrated before the Surgical Congress in 1892. The method gradually made its way, however, and was for some years almost the sole method in general use. In spite of the improvements in technique made since that time, it will probably never be abandoned alto- gether, but will be employed from time to time in specially suitable cases. Side by side with this method of tenninal ances- thesia, in which the sensory nerve-endings in the area of operation itself are acted upon by anaes- thetic solutions, another method has been evolved which has gradually surpassed it in importance, a method which, following Braun, we name regional or conduction ancesthesia. In this method the actual site of operation is left uninterfered with, but the conduction of sensory impulses therefrom is interrupted by injections into the neighbourhood of the nerve-trunks supplying it. The originator of this method is the American, Corning, who, in 1887, by means of injections around the N. cutaneus antebrachii, produced an anaesthesia of the cutaneous area supplied by that nerve. The method remained of little importance in prac- 10 LOCAL ANESTHESIA tice until 1890, when Oberst and Pernice, who were unacquainted with Coming's experiments, rendered a finger anaesthetic by ligaturing the base and injecting the neighbourhood of the nerve- trunks in which ran the finger's sensory fibres. A further step forward was Hackenbruch's circular analgesia. In this method injections of anaesthetic solutions are made all round the site of operation, the conduction of the sensory im- pulses therefrom being thus entirely interrupted. Hackenbruch employed a solution, consisting of equal parts of J per cent, solutions of cocain and eucain. In Oberst s method the injections are made perineurally, and the solutions reach the nerves themselves by diftusion. Krogius has suggested endoneural injections, but the method has as yet little practical importance. The perineural method, on the other hand, has been widely de- veloped. Hall applied it to the infra-orbital nerve, Hallstedt to the inferior alveolar, and Manz to the larger nerve-trunks in the hand and foot. It is to Braun, however, who in his textbook of local ana3sthesia, published in 1905, gives detailed descriptions of technique applicable to every region of the body, that credit is chiefly due for the development of the method. Braun's later work has been chiefly devoted to a confutation of Schleich's views, according to which physical HISTORICAL SURVEY 11 factors — osmotic tension, oedema, pressure — play the chief part in producing anaesthesia, the anaes- thetic itself having only a secondary role. We have to thank Braun, also, for another notable advance — the introduction of preparations from the suprarenal gland, which, injected with the anaes- thetic, lessen the risk of poisoning and at the same time increase the local effect. Important progress has been made during the last few years in another direction. Experimental chemistry has furnished us with substitutes for the poisonous cocain, which, while considerably less toxic than that substance, are not markedly less effective as anaesthetics. Among these novo- cain has, in consequence of its combining high anaesthetic efficiency with low toxic power, come very rapidly into general use, and is employed now by the majority of surgeons. So far, indeed^ has this displacement of cocain by less toxic sub- stitutes advanced that Bier was justified in saying at the Surgical Congress of 1909 that, except for operations on the mucous membranes and the eye, cocain ought no longer to be used. Another advance we owe to chemical industry is the synthetic production, a few years ago, of the bodies to which suprarenal preparations owe their efficacy. The latest development to which we would draw attention, as it opens up a new field for local 12 LOCAL ANESTHESIA anaesthesia, is the introduction of Bier's venous aiiwsthesia, in which J- per cent, solution of novo- cain is injected into a vein between two Esmarch's tourniquets appHed to the arm or leg. An anaesthesia is produced in this way which is fully sufficient for the performance of major operations, such as resections or amputations, between the two ligatures, or at any point peripheral to them. CHAPTEP. II PHYSICAL PEINCIPLES If we inject some ordinary tap-water underneath the human epidermis into the cutis (endermal injection), a whitish weal is produced, somewhat resembhng that caused by the sting of an insect ; at the same time fairly acute pain is felt, and this is followed later by an ansesthetic condition hmited to the area of the weal. This, too, gradually passes away. The cause of the pain and of the subsequent anaesthesia is as follows : If we have in a vessel two solutions of the same salt, but of different concentrations, whether separated by a permeable membrane or not, an exchange of molecules will take place between the two : molecules of the salt will pass from the more concentrated to the more dilute solution, while molecules of water pass simultaneously in the opposite direction. This exchange proceeds, if both solutions are of the sanie salt, until the solution is of the same concentration throughout. Before diffusion there is a condition of so-called 13 14 LOCAL ANESTHESIA " osmotic tension " between the two solutions. The more concentrated solution is said to be " hypertonic " the more dilute " hypotonic." After diffusion we have an '' isotonic " condition, in which the solution presents the same molecular concentration throughout. If the salts in the two solutions are not identical, then, for each concen- tration of the one solution, a certain definite con- centration of the other is required to bring about the isotonic condition, in which no exchange of molecules, whether of salts or of solvent, takes place. The simplest method for estimating osmotic tension is the determination of the freezing-point of the solution dealt with. Isotonic solutions have the same freezing-point ; in hyperosmotic (hypertonic) solutions the freezing-point is lower, in hyposmotic (hypotonic) solutions it is higher. If, now, we apply the foregoing to our chosen example, we have, after injection of water into the cutis, an exchange of molecules, for the reason that the lymph or blood flowing through the tissues has a relatively high saline content, and is therefore hypertonic to water, so that saline particles pass from the blood and lymph to the injected water, and, on the other hand, water diffuses itself through the tissues, producing a sodden or soaked condition (Quellung). This soaking of the tissues is the cause of the phe- nomena we observe. It irritates the sensory nerve- PHYSICAL PRINCIPLES 15 endings, thus causing pain (Quellungsschmerz), which is followed by a condition of anaesthesia (Quellungsanclsthesie, Braun). Injection of con- centrated solutions, in consequence of the abstrac- tion of water it brings about, also causes, though in a slightly different way, pain with subsequent anaesthesia. The anaesthesia, preceded by pain, which is caused by injections of water is named, after Liebreich, '' anaesthesia dolorosa." It is not a suit- able method for producing local anaesthesia in actual practice, for the reason that the injection of substances markedly hypotonic to the tissue fluids, apart from the pain it produces, actually injures the tissues, as is proved by the frequent occurrence of necrosis after injections of water [Braun). If common salt is added to the water injected, it is found that both the pain and the subsequent anaesthesia diminish as the concentra- tion of the solution increases, and a point is finally reached at which the salt solution (0*9 per cent., or "physiological" salt solution) causes neither pain nor anaesthesia. The freezing-point of the tissue fluids is, at this point, the same as that of the salt solution. If we now carry the concentration of the salt solution further, the phenomena of pain and subsequent anaesthesia are again elicited. They are, however, to be ascribed now, not to the soaking of the tissues, but, on the contrary, to 16 LOCAL ANESTHESIA their beiDg drained of fluid {Braun). We have, then, in physiological salt solution, a combination which neither causes pain when injected, nor injures the tissues, and constitutes, therefore, an ideal vehicle for anaesthetizing substances. The absence of either " soakage " or " drainage " anaesthesia is of little importance in view of the pain -deadening power of the substances we employ as local anesthetics. We require of the anaesthetic itself, no less than of the vehicle in which it is dissolved, that its injection shall be free from pain, and shall not cause injury to the tissues. Braun and Heinze have tested a large number of substances by Schleich's method, and have found very few which meet our requirements fully in these respects. Those which do so, and are therefore suitable for use as local anaesthetics, exert their anaesthetic powers, when injected endermally, in very dilute solutions. The method of testing an anaesthetic by injecting it so as to form weals is, however, only valid if the object for which we wish to employ the sub- stance tested is the production of anaesthesia of the skin or mucous membrane. Other laws come into operation where diffusion through several tissues is in question, as, for instance, when a mucous membrane is rendered insensitive by external application of the anaesthetic. PHYSICAL PRINCIPLES 17 Thus tropacocain, which is quite useless for the production of infiltration anaesthesia, is used by many ophthalmologists for subconjunctival instil- lation. The laws of diffusion apply, of course, as fully to endermal as to hypodermic injection. Of special importance here is the fact that concen- trated solutions, after injection, continue to take up water from, and give up their salts to, the tissues, until a condition of osmotic equilibrium obtains. We can thus, by injecting a concen- trated solution of an anaesthetic merely into the neighbourhood of an organ such as a nerve, secure, by means of the diffusion process set up, the gradual passage of the anaesthetic into the nerve itself. CHAPTER III LOCAL ANESTHETICS Though, as we have stated above, cocain itself is no longer widely used, it, nevertheless, as the first of modern local anaesthetics, and the one from which nearly all those in common use to-day may be said to have been derived, deserves special and prior mention and consideration. Cocain, an alkaloid obtained from the leaves of the coca-plant, was first isolated by Niemann and Lossen in Wohler's laboratory. Later it was pro- duced synthetically. Commercial hydrochlorate of cocain of the present day is a white powder freely soluble in water and alcohol. It is odourless, but has a bitter taste. The nature of the local action of cocain has been a subject of prolonged controversy. It was formerly held that it acted by virtue of its power to produce anaemia, as it is known to cause contraction of the smaller blood- vessels and capillaries. This anaemia certainly plays a part in cocain anaesthesia, which we shall consider later ; the actual anaesthetic effect, how- ever, depends on a purely chemical action, on an 18 LOCAL ANiESTHETIGS 19 affinity between the drug and the protoplasm of the tissues, which gives rise to a chemical combina- tion, of whose exact composition we are at present ignorant. That the anaemia is not the efficient cause of the anaesthesia is proved by the following facts : 1. Gocain has been found to produce its anaes- thetic effect even when the blood in the vessels has been replaced by salt solution. 2. There is a whole series of preparations which are efficient producers of local anaesthesia, but do not cause simultaneous anaemia — e.g., eucain. The aqueous solutions of cocain which were in general use until the introduction of the modern substitutes are all strongly hyposmotic or hypo- tonic. Their freezing-point varies, according to Braun,from 0*02° (O'l percent, solution) to 0*11 5^0. (1 per cent, solution), the freezing-point of human blood being about 0*55° C Their injection, never- theless, causes no "infiltration pain" (Quellungs- schmerz), as this is overborne by the essential anaesthetic effect of the drug. Different kinds of protoplasm have different degrees of chemical affinity for cocain ; what chiefly concerns us is the high degree of affinity in the case of the sensory nerves. Thus, according to Braun, a 0*005 per cent, solution of cocain injected so as to produce a weal is sufficient to deaden for a short time the sensory nerve-endings within the 20 LOCAL ANESTHESIA weal. By this property of acting in very dilute solutions cocain and its derivatives are clearly dis- tinguished from a whole series of other substances which act as anaesthetics when injected, but all belong more or less to the group of ancesthetica dolorosa, and, being consequently of no practical value, need not be enumerated here. It is important to remember that tactile and pressure sensations are diminished by cocain later and in less degree than sensations of pain. Thus it often happens that patients in whom sensibility to pain has been entirely removed at the site of operation will be conscious of the pressure of the surgeon's knife, or of the drawing apart of the edges of the wound, and this may lead in nervous and excitable patients to failure, or comparative failure, if sufficient time be not allowed for the anaesthetic to produce its full effect on sensation. The senses of smell and taste are also inhibited by cocain, but here, too, later than sensations of pain. The motor nerves are much less affected — so little, in fact, that the effect of cocain upon them is as a rule practically negligible. It is only in the so-called venous ancesthesia that motor paralysis serves to announce the commencement of anaes- thesia. The greatest sensitiveness to the action of cocain is, however, exhibited by the central nervous system. If, over and above the cocain LOCAL ANESTHETICS 21 remaining and acting at the site of injection, any considerable quantity of the drug should make its way into the general circulation, symptoms refer- able to the brain and spinal cord will be the first to manifest themselves, cardiac symptoms being the next in order of appearance. Cocain-poisoning was, not so very long ago, a factor of considerable importance in local anaes- thesia, and though, fortunately, it now rarely comes under our notice, some consideration of its symptoms and prophylaxis will help towards a clear understanding of the whole subject of local anaesthesia ; such consideration is called for, also, in view of the fact that cocain is still freely used both by ophthalmologists and dental surgeons. In acute cocain-poisoning (with which alone Ave have here to do) the patient is seized, almost im- mediately after the injection, w^ith giddiness, which in severe cases passes on to a condition of syncope ; palpitation is generally present ; the face is pale, the pulse small and rapid ; as a rule the patient feels anxious and oppressed, with a sensation of tightness across the chest. The whole symptom complex may be referred in part to contraction of the cerebral bloodvessels, in part to a specific action on the cerebral cortex. In the milder cases the patient recovers after a few seconds or minutes ; in the more severe the dominating feature is a condition of excitement 22^ LOCAL AX^ESTHESIA resembling in some resjDects that due to alcoholic intoxication. In fatal cases death due to paralysis of the resjDiratory centre is ushered in by convul- sions and coma. In severe cases which do not end fatally the patient exhibits extreme excitement, and talks volublv like a slio-htlv drunken man. There is generally marked anxiety, with dryness of the throat and tingling or numbness in the extremities ; the pupils are dilated and fixed. In most non- fatal cases recovery is rapid ; occasionally, how- ever, a condition of debility supervenes which lasts for a considerable time. Of the very first importance in connection with the causation of cocain-poisoning is the fact, estab- lished clinically by Schleich, and experimentally by Maurel, that a qiven dose of cocain which, injected in concentrated solution, will give rise to severe toxic symptoms^ may he quite tcell borne if giveii in a dilute solution. The maximum dose of cocain is often given as 0*05 gramme (Ov7 grain). Such a state- ment is entirely futile. I can inject twice that dose in a O'l per cent, solution without risk, whereas a fraction thereof in a 5 per cent, solution may produce most alarming symptoms of poison- ing, or even cause death. It requires a very short time to produce cocain-poisoning when cocain, in solutions over and above a certain concentration, reaches the blood-stream. The explanation of this fact put forward by LOCAL ANESTHETICS 23 Schleich is that around the small ischsemic oedematous area, where the small quantity of concentrated solution lies deposited, a collateral hypersemia, with increase of blood-pressure, is established, which, by causing pressure from without, forces the cocain into the lymph channels, whereas, where a larger deposit of more dilute solution is in question, this action from without is exerted more gradually, so that absorption is delayed. Simple suction by the lymph-stream is a factor which may, in Schleich's opinion, be neglected. We cannot agree with this explanation of Schleich's, for we find that the rule holds also for injections which are not made according to Schleich's method, and in which cedema and ischsemia of the tissues cannot play any part. Further, it holds also in the case of applications to a mucous membrane, where it is, of course, beyond question that no pressure is exerted on the cocain solution. The following seems to us a far simpler explanation : Let us assume that we have in a cubic centi- metre of a 1 per cent, solution 100 molecules of cocain, then in a cubic centimetre of a 10 per cent, solution we shall have 1,000 molecules. Now, if we inject these two cubic centimetres under the skin of two separate individuals, a fluid deposit of the same size will be formed in each case. In 24 LOCAL ANAESTHESIA the first case the 100 molecules will readily find 100 molecules of protoplasm with which to combine, thus remaining anchored, so to speak, at the site of injection. The 1,000 molecules, however, will not find molecules of protoplasm to combine with and fix them all, and the surplus, say 500, will pass quickly into the blood-stream, and so reach the central nervous system and give rise to symptoms of acute poisoning. Such being the conditions which determine the the supervention of cocain-poisoning, it is possible to infer from them what objects we have to aim at in order to obviate the dangler — 1. We must endeavour to delay the absorption of cocain into the bloodstream. 2. We must use solutions as dilute as possible. The first point will be dealt with in the next chapter ; as regards the second it has been found that a 1 per cent, solution is the strongest that should be injected subcutaneously, and this only when special means, which w^e shall discuss later, are adopted with a view to delaying absorption ; and I cannot help suspecting that Reclus, who states that he has performed several thousand operations with use of 1 per cent, solutions, without a death, must have used preparations of cocain weaker than those at present at our disposal, or that his sterilizing precautions must in some way have weakened the action of his injections. LOCAL ANESTHETICS 25 According to Brauii, the largest quantity of a 1*0 per cent, solution, with suprarenin, which can be regarded as safe is 5 c.c, whereas of a O'l per cent, solution 100 c.c, or double the maximal dose of cocain in the more concentrated solution, can be injected without risk. Dosage becomes a matter of great difficulty in apj)lications to the oral and nasal mucous mem- branes. Here, in order to get anaesthesia, one must paint with 10 to 20 per cent, solutions. In this method it is quite impossible to say how much is absorbed. It is important that the solution should be applied, not to a large area of mucous membrane at once, but to small areas, if necessary, in succession. With all precautions, however, as I have learnt from repeated experi- ences, it is impossible to avoid cocain-poisoning altogether and with certainty in this method, though I have not seen any really severe cases. The best precautionary measure would be to avoid cocain altogether, and use only its sub- stitute preparations {ctlypin, novocain) ; it must be admitted, however, that a considerable number of authors consider cocain to be superior to its substitutes as an anaesthetic for mucous membrane. In the case of hollow organs (such as the bladder or the interior of a joint), where we can give the drug sufficient time to produce its 26 LOCAL ANESTHESIA effect, satisfactory results are obtained with quite dilute solutions (0*1 and 0*2 per cent.). It ought not to be necessary to insist that cocain should not be injected into young children. Nevertheless, even infants in arms have been successfully cocainized. Special care is necessary with cocain in the case of anaemic and cachectic patients, as such patients often exhibit marked intolerance of the drug. In the treatment of acute cocain-poisoning the first indication is to place the patient in a hori- zontal position, w^ith the head somewhat lowered. The face should be sprinkled with cold water, and all windows should be opened. If amyl-nitrite is at hand, a few drops should be admiaistered by inhalation. Though, according to Dastra, it is not theoretically an antagonist to cocain, it, never- theless, often acts exceedingly well in practice. In women all constricting garments should, of course, be loosened. In severe cases caffeine or camphor should be given hypodermically, the body should be vigor- ously rubbed or flicked with wet towels ; should the breathing begin to fail, artificial respiration must be resorted to. The sterilization of cocain must be carried out with great care, as the drug is readily decomposed by heat, with loss of anaesthetic power. Above all things, it is important that the solutions employed LOCAL ANESTHETICS 27 should be made immediately before use. The simplest method of sterilization is to raise the solution once to the boiling-point. Cocain will bear this without undergoing decomposition. Pro- longed boiling causes decomposition of the active substance. According to Braun, cocain in powder or tablet form may be heated to 80° C. for an hour on each of three successive days, and then dissolved in sterile salt solution. Chemists have for a long time endeavoured to provide substitutes for cocain. which, while little, if at all, less powerful as anaesthetics, shall be without its toxic properties. Of the substances with which chemical industry has furnished us up to now some are chemically closely allied to cocain {trojjacocain, eucain, novocain), while a series of others belong to the orthoform group (orthoform, nirvanin). Only a few of these bodies have established themselves in practice. We will deal here with the more important of them. Tropacocain is much, used in spinal anaesthesia, of which we shall not treat here, as it is not, strictly speaking, a form of local ansesthesia. It has also proved useful in 2 to 3 per cent, solutions in ophthalmology. When injected subcutaneously, however, it is of use only for operations of very short duration, as its anaesthetic eflPect quickly passes ofP. It does not, like cocain, cause anaemia, nor has it been found to cause injury to the 28 LOCAL ANESTHESIA tissues. According to Braun, up to 0'2 gramme of the substance may be given in 1 per cent, solu- tion. No by-effects have been observed from injections of solutions of that strength. Steriliza- tion is most conveniently carried out by boiling the solution for five minutes. Addition of supra- renal preparations does not increase the effect of tropacocain. Eucain /3, which was at one time widely used, has now almost disappeared from practice. Its property of causing hypersemia and the impossi- bility of combining it with suprarenal prepara- tions, have stood in the way of its extended use. Its use is now practically confined to ophthal- mologists, many of whom still recommend it for subconjunctival injections. To the two hitherto recorded cases of poisoning I am able to add a third. A solution of 1 in 30 was injected into the slightly ulcerated bladder of an elderly man. The most severe collapse followed immediately, com- plete pulselessness and cessation of respiration. The condition seemed desperate, but artificial respiration, with injections of camphor and caffein, brought the patient round in about ten minutes. Alypin, a glycerin derivative [mono chlorhydr ate of benzoyl), is now used by many ophthalmologists in place of cocain. The drug acts on the eye in about the same strength of dose as cocain, but is LOCAL ANAESTHETICS 29 less poisonous. The lethal close is about double that of cocain. Alypin differs from cocain in caushig dilatation instead of constriction of blood- vessels. It does not, like cocain, cause mydriasis nor paralysis of accommodation. It may be com- bined with suprarenal preparations. It is, further, less harmful to the cornea than cocain. It may be sterilized by boiling for five to ten minutes. Solu- tions of 2 per cent, strength are generally used for conjunctival instillation. In rhino-laryngology, also, the drug has many advocates. It is here painted on the mucous membrane in 10 to 25 per cent, solution. Alypin shares with novocain the preference of a good many surgeons. Apart from Schleich, who uses it as a substitute for dilute solutions of cocain, Schloffer, for instance, has carried out with it a series of strumectomies. For infiltration 0*5 to 2 per cent, solutions are employed. So far as I am acquainted with the literature of the subject, no mishaps have been reported from its use. Stovain, on account of its irritating properties, is not suitable as a local aneesthetic. A substance which has rapidly won for itself, in the estimation of general surgeons at any rate, the first place as a local ansesthetic is novocain {Maister, Lucius, and Braning), which during the last few years has assumed a position of com- manding importance in surgery, so that, in most 30 LOCAL ANESTHESIA of the great surgical cliniques, it is now exclu- sively employed for anaesthetic injections. Novocain [monochlorhydrate of para-amido- henzoyldiethylaTiiidoethanoT) is a white, crystalline powder, which can be heated to 120° C. without decomposing, and is readily soluble in water and alcohol. Pharmacological tests and clinical experience alike have shown that the drug does not act as an irritant even in concentrated solutions. Its toxicity is only about one-seventh of that of cocain. So far as I am aware, no case of novocain-poison- ing has yet been recorded in practice. Occasion- ally injections of large doses have been followed by slight faintness and pallor ; these, however, have been quite transient. Half a gramme (7 '7 grains) of the drug may be injected in 1 per cent, solution without risk. I have injected as much as 80 c.c. of such a solution — i.e., 0"8 gramme, or 12 '3 grains, of the drug, without any untoward symptom. It has been stated that novocain is quite as powerful an anaesthetic as cocain. This is, how- ever, not quite correct. In Oberst's method we have found that its action is weaker, the anaes- thetic efficiency of its solutions being about as 1 : 2 when compared with solutions of cocain of equal strength. The non-poisonous character of the drug, however, admits of our employing LOCAL ANESTHETICS 31 double the maximum dose of cocain. Solutions of novocain may be boiled for ten minutes with- out losing strength. Novocain does not, like cocain, cause local anaemia ; where this effect is desired, therefore, suprarenal preparations must be added to the solutions. While eucain /3 loses in anaesthetic power through the addition of adrenalin, novocain, on the contrary, has its efficiency heightened. Novocain is also very suitable in 10 to 20 per cent, solutions as an anaesthetic for mucous membrane. It has here, however, to compete with alypin, which is also widely used, while cocain also has, in this connection, many advo- cates. An advantage attributed by many writers to novocain is that there is much less pain after its employment than is the case with cocain. I do not think, however, that there is, in this respect, any very great difference between the two drugs, the intensity of the after-pain depend- ing much more on the quantity and concentra- tion of the added suprarenal preparation. When the various factors are taken into con- sideration, there is no doubt that the introduction of novocain represents a notable advance, as, indeed, the very rapid extension of its employ- ment sufficiently proves. Finally, mention must be made of the anaes- thetics which act by production of cold. These 32 LOCAL ANESTHESIA played formerly quite an important part. They have now, however, been relegated to a very subordinate position, and are employed only for trifling operations. Ansesthesia from cold is a terminal ansesthesia, the organs acted upon being the sensory nerve-endings. Sulphuric ether, which was at one time very widely used, has now been almost entirely dis- placed by more powerfully acting substances. It was sprayed on to the skin or mucous mem- brane by means of Richard- son's ether spray (Fig. 1). The apparatus consists of a bottle filled with ether and fitted with a perforated cork, through w^hich passes a tube, one eod of which is covered by the ether in the bottle, while the other is drawn out to a fine point. By means of the well-known rubber bulb arrangement air is forced into the bottle, the increase of pressure forcing the ether along the tube until it emerges at the fine exit from the nozzle in a jet of minutely-divided spray, which is directed on to the skin or mucous membrane. The degree of cold produced by evaporation of the ether reaches about - 15° C. The ether — anaesthetic ether free from water must be used — is sprayed on to the Fig. 1. LOCAL ANESTHETICS 33 skin from a short distance. After a few minutes the skin becomes white and frozen. Until this change occurs the anaesthesia is not complete. If the blanching is delayed, a slight mechanical irritation such as a prick with the point of a knife is often sufficient to bring the skin or mucous membrane quickly into a frozen condi- tion. The ether spray is useless in a very warm room, as under such condition the necessary degree of cold cannot be attained. The more vascular the tissue, the more difficult it is to bring it to the freezing-point. Formerly the extremities were frequently rendered bloodless by the ordinary surgical methods before applying the spray. Before the onset of the anaesthesia pain is often felt, slight if the skin be healthy, but often severe if it be inflamed. The thawing of the frozen parts is always accompanied by a condition of hypersesthesia. The drawbacks associated with ether, the slow irregular onset of the anaesthesia and its slight intensity, have led to the adoption of other substances with a lower boiling-point, whose spray, therefore, produces a greater degree of cold by evaporation. The most useful of these sub- stances is ethyl chloride or chlorethyl, CJlfil. This compound boils at 11° C, thus at about the ordinary room temperature. It is supplied in glass tubes containing 15, 30, 50, or 100 c.c. 3 34 LOCAL ANESTHESIA The tubes are generally fitted with an automatic tap {h, Fig. 2), which enables one to close or open at will a fine opening at one end of the tube, so that by holding the opening downwards a fine jet of the fiuid can be obtained. It is very necessary — and this point is often neglected— to remove fats from the skin by benzine or ether before applying the chlorethyl ; otherwise one must Fig. 2. often wait a long time for the onset of anaes- thesia. The tube must not be held too near the part to be treated, but must deliver its jet from a distance of about 30 centimetres (1 foot), so that evaporation may have already begun when it reaches the skin or mucous membrane. The buccal mucous membrane is often difficult to freeze on account of the passage over it of the warmed LOCAL ANAESTHETICS 35 breath. For tooth extraction Kuehnen has intro- duced a special bifurcated attachment by which both aspects of the gum may be simultaneously sprayed in a manner similar to that in use with ether. The tissues must, of course, only be sprayed until blanching appears ; otherwise per- manent injury may be done. It has been stated that with ethyl chloride it is not safe to render the part bloodless, as is frequently done with ether, as the effect pro- duced is likely to be too powerful. I hardly think there is any real danger of the kind, but as the application of a tourniquet is uncomfort- able and has little effect in intensifying the anaesthesia, there seems no advantaofe in its use. The pain which often comes on before the onset of ansesthesia is more severe than with ether, in consequence of the more rapid freezing. It is especially marked if the tissues be inflamed. With ether, again, a deeper effect can be produced than with ethyl chloride. Neverthe- less, I cannot advocate, with Braun, a return to a more extended u.se of the ether spray, and I think few who have had much experience of the annoyance and loss of time inseparable from the method will prefer it to the more convenient ethyl chloride, in spite of the fact that the latter possesses also some disadvantages. Of substances possessing a still lower boiling- 36 LOCAL ANESTHESIA point than ethyl chloride I have practical experi- ence only of ansestol [Speyer and Karger). This is a mixture of chlorethyl and chlormethyl, the latter of which boils at -23° C. It acts rather more rapidly than chlorethyl. I have seen no injury to tissue from its use, though I have applied it for some minutes in attempts to remove an angioma. For the production of still more intense effects of cold, such as can be produced by the use of methyl chloride, or of liquefied or solidified carbonic acid, there is, for purposes of ^ local anaesthesia, no necessity. The danger of injury to the tissues, too— gangrene of the skin has been observed after the use of methyl chloride— must be held to contra-indicate the use of these sub- stances in practice. CHAPTER IV ADJUVANTS IN LOCAL ANAESTHESIA These all have one thing in common : they act upon the circulation in such a manner that the blood-stream is slowed at the point where the local anaesthetic is required to produce its effect. By this slowing of the blood, and consequentially of the lymph -stream, the absorption of the an- aesthetic is delayed, and the danger of general poisoning therewith lessened. Another conse- quence of this delaying of absorption is that the anaesthetic is allowed to remain longer about the site of injection, where it may form combinations with the protoplasm of the tissues, and thus develop to the full its anaesthetic effect. This effect of a slowing of the blood-stream may be demonstrated experimentally as follows : a certain quantity of an aqueous solution of eosin is injected endermically into one arm and a similar quantity into the other after application of a tourniquet. It is then seen that on the ligatured side a very much larger quantity of the colouring matter remains and becomes diffused about the 37 38 LOCAL ANESTHESIA site of injection than is the case on the unhgatured, on which a far larger quantity of the eosin has obviously been taken up into the general blood- stream (^Braun). This delay of absorption, with its converse intensification of local action, involves in its turn a certain danger. By the slowing of the blood- stream at the site of injection the vitality of the tissues is diminished, and too prolonged and too intense action of the anaesthetic on the proto- plasm within its reach may lead to injury to the tissues ; one must aim, therefore, at such a balancing of effects that the anaesthesia may be as complete as possible without involving any harmful toxic action on the tissues. 1. Cold. Cold has not won a position of any great importance as an adjuvant in the production of local anaesthesia. Brief mention, however, may be made of methods of application which have had a certain vogue. {a) Tubes of cocain-chlorethyl are now sold containing solutions of cocaln in ethyl chloride of different concentrations (1 to 5 per cent.). When this preparation is applied to mucous membrane, sensibility is abolished temporarily, and returns only with the thawing of the frozen parts. Then, ADJUVANTS IN LOCAL ANESTHESIA 39 after a time, there supervenes an intense cocain anaesthesia, which is of considerable duration. The same result may be brought about by painting the surface with cocain solution and then applying the ethyl chloride jet. The nature of the action is as above explained. Absorption is slowed, or even abolished, in the cooled parts, and the local action of the cocain thereby intensified, and the risk of general poisoning diminished. The introduction of the suprarenal prepara- tions, to be dealt with later, has rendered this method of applying anaesthetics more and more superfluous. In tooth extraction, for which the method was especially advocated, it enables us to anaesthetize merely the mucous membrane, not the sensory nerves supplying the tooth. (b) Schleich has recommended the injection of powerfully cooled solutions, again with a view to the slowing of absorption and the intensification of local action. Others {Braun), when, for some reason, they do not wish to make use of supra- renal preparations, frequently apply the ether spray in order to heighten the local effect of an ansesthetic injection. I have never found any such proceeding necessary. Schleich, too, seems but seldom to have recourse to it. 40 LOCAL ANAESTHESIA 2. Methods for rendering the Parts Bloodless. (a) Ligature. This method, to whose importance attention was first drawn by Corning, also acts by stoppage of the circulation and consequent inhibition of absorption and intensification of local anaesthetic action. Klapp has proved this experimentally. He injected solutions of milk-sugar under the skin of the arm. The sugar was rapidly absorbed and excreted in the urine. The application of a tourniquet caused a marked slowing of absorption. It was formerly thought that rendering a part bloodless had in itself an anaesthetic effect. Braun has shown, however, that anaesthesia follows the application of a constricting band only if the band is applied very tightly so that the nerve-trunks are compressed. The anaesthesia brought about in this manner depends, therefore, directly on the tightness of the constriction and the position of the nerve-trunks at the point where the constrict- ing band is applied. It is quite uncertain, and therefore of no practical significance. In operations on the fingers and toes the emptying of the parts of blood has been widely adopted as an auxiliary to the so-called Oherst's Anoesthesia. At the present time, however, the ADJUVANTS IN LOCAL ANESTHESIA 41 use of suprarenal preparations is generally pre- ferred. Bloodless methods cannot, however, be dispensed with altogether. If the bandage is carefully and not too tightly applied to the fore- arm — a tight constriction is not at all necessary — the method has few, if any, drawbacks. It is specially applicable when the site of operation is at the base of the finger, or at a still more central point, where -an anaesthetic condition is not so easily attained as in the finger itself, and when we wish to avoid using the larger dose of supra- renal extract which is here generally necessary. The use of constriction to render the afiected parts bloodless is again playing an important part since the introduction of Bier's method of venous ancesthesia. As we have stated, in this method a section of the limb having been rendered bloodless and included between two constricting bandages, a i per cent, novocain solution is injected into one of its veins. Bier has shown that fluids pass through the venous wall with extraordinary facility. The solution, therefore, injected under pressure into the vein rapidly permeates all the tissues within its reach. {b) Infiltration (Schleich). In Schleich 's view chemical factors play only a secondary part in his method of " oedematizing " the site of operation. Their function is to counter- 42 LOCAL ANESTHESIA act the pain due to the injection ; the chief part is played by the 2 per cent, salt solution, and anaemia and pressure act as auxiliaries. The action of the 2 per cent, salt solution will be considered in the next chapter. Ansemia plays a certain part if the method is correctly carried out — that is to say, with production of a marked degree of (Bdema. It acts in the manner described at the commencement of this chapter, enabling us to make use of dilute solutions and heightening the local effect of the anaesthetic by causing a slowing of absorption. (c) Suprarenal Preparations. These have of late years gained a position of steadily-increasing importance in the practice of local ansesthesia. After attention had been drawn by Pellacini to certain pharmacological properties of suprarenal extract, a series of investigators [Tilrk, Abel, Takanwie, Aldrich, Oliver, Schdfer) w^orked at the isolation of its active principle with ultimate success. A number of different prepara- tions were now put on the market in corre- spondence with the different methods of manu- facture employed ; suprarenin (Hochst), epirenan {Byk), paranephrin [Merck), adrenalin {Parke, Davis) and others. These have all approximately the same constitution. Following the suggestion of Braun, to whom we owe the introduction of the ADJUVANTS IN LOCAL ANAESTHESIA 43 suprarenal preparations into the practice of local ansesthesia, we shall hereafter include them under the general name suprarenin. Suprarenin is a white powder which dissolves freely in water, but combines with the oxygen of the air as it does so, and takes on a reddish or brownish tint. On the other hand, it dissolves freely also in dilute hydrochloric acid without undergoing any change. It is therefore generally sold in the form of a solution of suprarenin hydro- chloride (1 in 1,000). In speaking in the ensuing pages of suprarenin solution generally, we must be understood, unless otherwise stated, to refer to the 1 in 1,000 solution. Solutions in boric acid are less frequently used. Hochst's preparation contains an added 6 per cent, of thymol. The solutions are readily decomposed by heat. On standing, also, they soon undergo change and take on a reddish tint. Solutions in this condition should on no account be used. Apart from the fact that solutions which are no longer clear show a diminished efficiency as anaesthetics, poisonous substances are formed in solutions which have been kept for any length of time, and these may give rise to unpleasant symptoms {vomiting, after-pain, etc.). One fatal case, even, has been recorded. A positive result of the ferric chloride reaction — an emerald- green coloration on adding ferric chloride to an acid solution ; changing 44 LOCAL ANESTHESIA to red on addition of ammonia — is not at all reliable. The rubber corks with which the bottles are fitted in which suprarenal preparations are generally sent out are very inimical to the keeping powers of the solutions. If after opening the bottle — only bottles containing a very small quantity of the solution should be employed — a cork be substituted for the rubber stopper, the solution will remain in good condition for a very much longer period. The instability of suprarenal preparations, the impossibility of sterilizing them with certainty, and, not least, their inconstant action, have led to attempts to prepare them by synthesis. In this field Stolz, the chemist to the Hochst Works, has suc- ceeded in synthesizing several substances whose injection calls forth the same effects — increase of blood-pressure and peripheral vaso-construction — as does that of suprarenin. In their quantitative action, however, they differ among themselves materially. Arterenin (or arterenol) Braun found to re- semble suprarenin in its action. Others, how- ever, describe it as quantitatively inferior to that substance. It has disappeared from practice. Homorenon is described by the Hochst firm as being fifty times less poisonous than suprarenin. As, however, one must employ 5 per cent, solutions instead of those of 1 in 1,000 strength, the gain from ADJUVANTS IN LOCAL ANAESTHESIA 45 the lower degree of toxicity is very problematical. Further, accordiDg to Hoffmann, the activity of the preparation is lost by sterilization. It, like the former preparation, has failed to gain a place in practice. The preparation which has won the largest degree of recognition is suprareninum synthe- ticmn, which has been tested by various observers, and according to Braun and Hoffmann is a little more powerful in action than the substance obtained from the organ itself. It is, like the two foregoing preparations, a white crystalline powder, which is unaltered by exposure to air, dissolves in water acidulated with hydrochloric acid, and gives the ferric chloride reaction described above. It must be kept in a dark place, but will then remain unchanged for a considerable time. As a general rule a light rose colour develops in the solution, but only after it has been kept for some time. The solution can be sterilized by a brief boiling immediately before use. Repeated sterilization is not advisable, and, if only small bottles are used containing small quantities of the solution, hardly necessary. If making one's own solution of com- mercial suprarenin hydrochloride, great care must be taken that there is no free alkali in the glass in which the solution is boiled, as all the supra- renin preparations are very sensitive to the action of free alkali. To avoid this risk it is a good plan 46 LOCAL ANESTHESIA to use the small bottles supplied by the manu- facturers. The toxicity of synthetic suprarenin is somewhat less than that of the preparation made from the gland itself Judging from my own experience, the action of synthetic suprarenin is slightly weaker than that of its predecessors. The dose given by Hoffmann — viz., 2 minims to 10 c.c. of a 1 per cent, novocain solution — was frequently hardly sufl&cient to cause any marked anaemia. The dose I have generally employed for infiltration anaesthesia has been from 2 to 4 minims to 10 c.c. of the solution. That the ideal of an absolutely pure preparation has not been reached by this substance we may gather from the introduction by the Hochst firm of a new preparation, Synthetic L. Suprarenin, which turns the polarized ray to the left. This prepara- tion is more stable and more constant in its action than the first synthetic suprarenin, which has now been withdrawn from commerce. Experience w^ith this new suprarenin — clinical experience is the best criterion^ — is not at present extensive. So far as it goes, the preparation would seem to be of about equal activity with the earlier synthetic suprarenin. The whole suprarenin question is not yet fully cleared up. Different authors, for instance, differ widely from each other on the question of dosage. Further experience is required to decide whether our present dosage of synthetic suprarenin is not ADJUVANTS IN LOCAL ANESTHESIA 47 too high, and also whether some further attempt ought not to be made to separate the toxic from the useful elements. The maximal dose given by Braun, ^c.c. = 8*5 minims of the 1 in 1,000 solution, is, however, a very small one, and though perhaps as a rule sufficient, some slightly greater latitude as to dose may, I think, safely be allowed. No fixed scheme of dosage can, as a matter of fact, be laid down. In parts well supplied with blood more suprarenin must be used than in parts more poorly supplied. The presence of a considerable quantity of subcutaneous fat calls frequently for a free addition of sujDrarenin as an adjuvant to the anaesthetic. In small operations, too, in which not more than 5 to 10 c.c. of the anaesthetic solution are employed, we may safely add 1 or 2 drops more of the solution of suprarenin than in the case of larger operations w^here the dosage of anaesthetic already approaches the maximum. In general, the dosage of synthetic suprarenin may be put Sit 1 to 4: drops to 10 c.c. of ancesthetic solution in ''infiltration" and ''circular'' ancBS- thesia, 1 to 2 drops per c.c. for the interruption oj conduction in the larger nerve trunks. To pass to the effects of suprarenin preparations on the organism, the most prominent is an increase of blood-pressure, which comes on even after a minimal dose. The cause of this increase of blood- pressure is a direct action of the drug on the heart- 48 LOCAL ANESTHESIA muscle and on unstriped muscle throughout the body, especially on that of the medium sized and smaller bloodvessels. The rules governing the local action and absorp- tion of suprarenin are the same as in the case of cocain. Suprarenin, like the latter, combines locally with the tissue protoplasm, and conse- quently, if given in concentrated solution, yields up its surplus to the blood-stream more readily than if more dilute solutions are employed. Suprarenal preparations injected in large doses into the blood-stream have a powerfully poisonous action on the organism. While small injections cause an increase of blood-pressure which gradually passes away, with larger doses there follows, after a transient rise, a fall of blood-pressure, which in severe cases may lead to pulmonary oedema, con- vulsions, paralytic phenomena, and death. Braun has studied the early stages of suprarenin-poison- ing on himself After subcutaneous injection of rather more than 0*5 c.c. of 1 in 1,000 solution he was seized with palpitation and a feeling of oppression ; the same quantity injected in 10 c.c. of salt solution caused no toxic symptoms. Of course, in intravenous injection a very much smaller quantity suffices to cause symptoms of general poisoning than is the case with paren- chymatous injections. The prophylaxis of general suprarenin -poisoning maybe summed up as follows : ADJUVANTS IN LOCAL ANESTHESIA 49 Give small doses in dilute solution. The maximal dose of 0*5 c.c. given by Braun is quite sufficient in the case of cocain anaesthesia. Even as an addition to novocain solutions, which, in my ex- perience, require somewhat larger additions than cocain, in view of the absence of any ansemia- producing action in novocain, this dose will gener- ally be found sufficient. The maximal dose of 10 c.c. of 1 in 1,000 solution, given by Miiller, must be regarded as, in the majority of cases, too large. The way in which suprarenin acts as an auxiliary in local ansesthesia will be plain from what we have said above. The contraction of the arterial musculature gives rise to a vaso-constriction at the seat of injection, and thus produces a con- dition of local anaemia, with slowing of the local circulation and consequent delay in absorption, the general result being an increase of local anaes- thetic action and diminution of general absorp- tion, with its attendant risk of poisoning. The duration of the anaesthesia is also increased by the addition of suprarenin. Suprarenal preparations have in themselves no anaesthetic action. Concentrated solutions empty the parts so completely of blood that not a drop issues even from the larger vessels. With correct application and dosage the parts become prac- tically empty of blood ; from the larger vessels 4 50 LOCAL ANESTHESIA there will be slight oozing, but no spurting of blood. This action of suprarenin is of assistance also in the conduction- anaesthesia which will be dealt with later on, for though here the supra- renin does not, as a rule, act directly upon the vessels in the operation area, nevertheless, the vessels passing to that area contract under its influence sufficiently to diminish materially, or even to inhibit, the blood-supply to the part. We have seen above that suprarenin combines with the tissue protoplasm. The combination is a somewhat transitory one ; at the same time, it is important to remember that when we use a mix- ture of a local anaesthetic with suprarenin we are injecting two substances, each of which has its own local poisonous action. The greatest caution is therefore called for. Injuries to tissue through the use of suprarenin have been pretty frequently observed, and several cases of gangrene have been reported in patients, the subjects of arterial sclerosis {Neugehauer). I myself, when the use of suprarenin was in its infancy, have seen cutaneous gangrene of the finger develop in a patient, a professional colleague. It would seem, however, that with our present dosage we are fairly safe from such mishaps. Schleich, on account of this risk of injury to tissues, rejects suprarenal preparations altogether. In this attitude, however, he is likely to stand ADJUVANTS IN LOCAL ANESTHESIA 51 alone. Almost every method has its dangers and its victims at first. Only gradually, as experience accumulates, do we learn to avoid the dangers. It is worth noting, too, that in Schleich's method the addition of suprarenin may probably be dis- pensed with, as the oedema it produces causes a sufficient degree of anaemia. The second danger associated with suprarenin, that of secondary haemorrhage, can now be avoided with some certainty. Large doses of suprarenin lead, after the initial vaso-constriction has passed off, to a loss of vascular tone with vaso-dilatation ; if dilute solutions are employed, this loss of tone does not occur, or occurs only in so slight a degree that it is not of practical significance. The galvanic current as an auxiliary in local anaesthesia is at present merely of scientific, not of practical, interest. Wagner and Hertzog apply to the skin, which is generally impermeable to aqueous solutions, an anode soaked in cocain solu- tion, and by this means bring about a local anaes- thesia. The method, however, though it has been given some trial also in dentistry, has not gained any real footing in practice. CHAPTER y METHODS OF LOCAL ANESTHESIA AND THEIR APPLICATION 1. Anesthesia produced by Cold. This method is, or at any rate should be, of but occasional application. With highly sensitive patients it is often advisable to render slight punctures painless by means of the ethyl chloride jet. This is especially the case if needles of large calibre have to be used, as in saline infusion. Broadly speaking, it is considerations rather of convenience than of necessity that determine the employment of the method. Small boils, quite superficial whitlows, visible splinters, etc., are suitable for operation under this method. It should, however, be definitely discarded in any case of more extensive inflammation. Especially is it to be avoided in any extensive phlegmon of the fingers or hand. In the out-patient depart- ment of any large hospital it is a very common thing to see cases of phlegmon burrowing deeply along the sheaths of the tendons or elsewhere in which, a day or two before, an incision has been 52 METHODS OF LOCAL ANESTHESIA 53 made under ethyl chloride ansesthesia. In such cases the operator cannot possibly have deter- mined which tissues were affected, still less how far the suppurative process spread. The operation must be quickly finished on account of the tran- sitory nature of the ansesthesia — if any sufficient degree of the latter be attained at all — and the part bound up under pressure — this generally causing severe pain— on account of the free bleed- ing which supervenes on the thawing of the frozen parts. It is the same with large boils or car- buncles. Here, in the first place, if the inflam- mation is severe, the application of the jet is itself painful, as also the process of thawing ; while, in the second place, the incision itself, however quickly made, often causes very severe pain, because, though the tissues through which the actual incision is made are insensitive, it is impossible so to make the incision as to avoid pressure on the excessively sensitive nerves throughout the whole inflamed area. I have often seen surgeons express astonishment at a patient's cry of pain, because they knew they had cut through frozen tissues only; and I have even heard them ascribe the patient's protest to prejudice against local ansesthesia. The fact that major operations— resection of scapula, ovariotomy, etc. — have been carried out under ansesthesia from cold is of merely historical 54 LOCAL ANESTHESIA interest. The attempt has likewise been made to render large nerve- trunks insensitive by the application of cold. The pain, however, which here precedes the onset of anaesthesia is so exceedingly severe as to surpass in most cases that of the operation itself In tooth extraction the method is only appro- priate when the tooth is quite loose and free from pulpitis, so that all that is required is to render painless prehension of the tooth by the forceps. A small operation which is quite satisfactorily carried out under ethyl chloride anaesthesia is removal of ingrowing toe-nail and excision of the bed of the nail. It is essential, however, in this operation that one should, before operating, see the tissues frozen white underneath the whole nail. If the oj)eration is then quickly performed, it can be completed without any pain at all. 2. Anaesthesia of Mucous and Serous Surfaces. As was stated in the first chapter, cocain was first applied as an anaesthetic to the conjunctiva. The anaesthesia is here a terminal one, and does not generally extend beyond the mucosa. Small doses are here generally sufiicient, as the anaesthetic does not flow away, but may remain in the con- junctival sac, exerting its action on the mucosa for a considerable time. METHODS OF LOCAL ANESTHESIA 55 In the case of many mucous membranes {e-ff;,, pharynx), the impossibility of accurate dosage has constituted a difficulty of some moment. As, in consequence of the limited degree to which diffusion can take place through the uninjured mucous membrane, very concentrated solutions (10 per cent, to 20 per cent, cocain solutions) have to be used, overdosage is difficult to avoid with certainty, and cases of cocain-poisoning, fortunately, as a rule, slight, have been fairly numerous. In these cases the use of the substi- tute preparations is especially to be desired, and in many surgical cliniques they have practically displaced cocain. The use of suprarenal prepara- tions admits, further, of the emj)loyment of more dilute solutions than could be used formerly. The concentration is, of course, dependent on the time that can be allowed to the solution to produce its effect, and in the method of external application to a mucous membrane by swabbing this is, of course, especially brief. Thus, for anaesthetizing the pharynx the solution must be about forty times as strong as for the bladder. An anaesthetic is often required to render pain- less the injection of an irritant solution (iodine, phenol) into a serous cavity, such as a joint or a hydrocele sac. The site of puncture is first '' infiltrated " with 0*5 per cent, novocain solution, to which suprarenin has been added, and the 56 LOCAL ANESTHESIA same solution is then, after the removal of the fluid present, injected into the cavity until the latter is tightly filled. In ten minutes complete anaesthesia will be established, and not only may drugs be injected, but contractures may be cor- rected so long as they are merely reflex, and not due to serious structural changes in the joint. 3. Schleich's Infiltration Anesthesia. In this method the operation area is infiltrated with a dilute anaesthetic solution in such a manner as to cause a marked oedema of the tissues, so that the subcutaneous cellular tissue, for instance, appears swollen and glassy. The skin in the neighbourhood of the coming incision is first infiltrated, and immediately afterwards the sub- cutaneous cellular tissue, then, gradually, deeper and deeper layers of the subjacent tissues. As the discoverer of this method, Schleich is entitled to the credit of having been the first to devise a really safe method of local anaesthesia, as it admits of the use of very dilute solutions of anaesthetic drugs. His discovery was novel in principle, and it is quite incorrect to speak of a Reclus - Schleich method of anaesthesia. Reclus adopted subsequently much of Schleich's tech- nique ; he worked, however, with 1 per cent, solutions of cocain, and was therefore able to METHODS OF LOCAL ANESTHESIA 57 Inject only very small quantities of the solutions, forming small deposits, so to speak, of concen- trated cocain solution, which gradually diffused themselves into the surrounding tissues, and only then produced any widespread effect. Schleich first anesthetized the skin by forming endermal weals, and then oedematized the subcu- taneous cellular tissue. Only after incision of these tissues, now insensitive, were the deeper layers infiltrated, step by step, with large quan- tities of solution. At first Schleich employed three solutions of cocain, a 0*2 per cent. (I.), a 0*1 per cent. (II.), and a O'Ol per cent. (III.). In each the cocain was dis- solved in 0*2 per cent, salt solution; a small quantity of morphine was also added. Recently Schleich has substituted alypin for a |)ortion of the cocain — in his view the two anaesthetics, when mixed, " heighten each other's potency " — so that the solutions he employs at present have the following formulae : Solution I. Solution II. Solution III, 01 cocain. 0'0.5 cocain. 0*01 cocain. 0*1 alypin. 0.5 alypin. D'Ol alypin. 0*1 sodium chloride. 0'2 sodium chloride. 0*2 sodium chloride. 100-0 aq. dest. 100-0 aq. dest. lOO'O aq. dest. It would seem that Schleich no longer adds morphine to his solutions ; we need not, therefore, discuss the significance of such addition 58 LOCAL ANESTHESIA Schleich believes that in the 0*2 per cent, solution of common salt he has found a fluid which, pos- sessing a concentration intermediate between that of physiological salt solution and pure water, can, like the former, be injected without causing pain, and, like the latter, when injected, causes anaesthesia. This 0*2 per cent, salt solution must then be regarded as, in itself, an anaesthetic, and this is the essentially novel feature in his method. A second factor of importance in the method is the artificially-produced oedema and consequent (1) ischsemia and (2) compression of sensory nerve- endings. Another factor working in the same direction is the diflerence in temperature between the blood and the solution, which is injected at the ordinary room temperature, or is even cooled before injection with a view to increasing the difference. The method is therefore, in the main, one depending on physical principles, the cocain itself fulfilling, in Schleich 's opinion, quite a secondary role, its main function being to deaden the pain caused by the actual infiltration, and especially to over-compensate for the hyper- aesthetic condition of inflamed tissues. If the operative procedures are carried out on absolutely healthy (uninflamed) tissues, they may be carried out quite satisfactorily with 0*2 per cent, salt solution alone, without any anaesthetic drug. The whole theoretical basis of Schleich 's teach- METHODS OF LOCAL ANESTHESIA 59 ing has been vigorously attacked by Braun, who challenges esj)ecially Schleich s views as to the part played in local anaesthesia by the 0*2 per cent, salt solution. We have seen above that a 0*2 per cent, solution does actually cause anaesthesia {Quellungsandsthesie) when injected. This anaes- thesia, however, is preceded by pain, due to the injection ; and though this pain is less severe than when pure water is injected, so also is the intensity and duration of the anaesthesia less than in the case of water. While, then, Braun freely admits that a slight, transient anaesthesia may be pro- duced by injection of a 0*2 per cent, salt solution, he maintains that the effect of a 0*1 per cent, solution of cocain, such as is contained in the most frequently used No. II. solution of Schleich, so enormously surpasses this " physical " anaesthesia as to deprive the latter almost entirely of significance. Another question is whether it is desirable to choose '2 per cent, salt solution as our fluid basis. It has been shown that distilled water acts, when injected, as a powerful tissue irritant. On the other hand, physiological salt solution is, as we know, entirely unirritating. We must, then, admit the strength of Braun's position when he contends for physiological salt solution as the ideal vehicle for anaesthetic solutions. If, then, a method can be devised in which physio- logical salt solution constitutes the vehicle, it 60 LOCAL ANESTHESIA must certainly be preferred a priori. Schleich states, indeed, that he has performed a large number of operations under his method, and has never seen any injury to tissue from it. No surgeon, however, finds all his operation wounds heal by first intention. Who can say, in many cases, whether some slightly unsatisfactory con- dition about a wound is to be ascribed to the catgut, to some failure in asepsis, or perhaps to the local anaesthesia ? Thus Bier, for instance, one of the earliest advocates of Schleich's method, speaks of his fear that it may cause injury to tissues (Surgical Congress, 1909). Hocher, also, in his latest teaching on operative surgery, expresses the same misgiving. Probably in this, as in other methods to be discussed later, certainty in this respect will only be arrived at by combining the experience of many great hospital cliniques. We may see a long series of laparotomies heal without complications, and yet not be justified in deducing therefrom the complete harmlessness of our methods in all cases. It is certain, however, that novocain is far less dangerous to tissues than cocain, and we may regard it as probable that in novocain we have approached a full and satis- factory solution of the problem in this regard. The second point on which Schleich lays stress appears to us of greater significance than his opponents admit. The ischsemia caused by the METHODS OF LOCAL ANESTHESIA 61 artificially-produced oedema is, if his method is correctly carried out, a very pronounced one. It is, in my opinion, a powerful auxiliary, and fulfils almost the same function as suprarenin. Where the oedema is very marked, pressure on sensory nerves may also come into play as an auxiliary. Difierence of temperature — increased by cooling the anaesthetic solution before injection — also tends to heighten anaesthetic eftect. Where Schleich's method is correctly carried out, the order of importance of the difierent factors is probably represented with sufiicient accuracy as ibllows : Anaesthetic (chief agent). Ischaemia of tissues (chief auxiliary). Soaking of tissues. Pressure on nerve-endings. Difference of temperature. Much of Schleich's theory, then, cannot be up- held at the present day. At the same time, it is not, in my opinion, correct to ascribe to the physical factors in Schleich's method an entirely subordinate role. They act as pow^erful auxiliaries to the anaesthetic itself, always, of course, assuming that the method is carried out strictly according to Schleich's directions. It is quite another question whether Schleich's method is to be regarded as the method of election 62 LOCAL ANESTHESIA at the present day. A disadvantage quite distinct from any we have considered above is the im- possibihty of distinguishing the tissues. In many operations, especially in infected tissues, this may be of little moment ; in others, however, especially where an exact differentiation between healthy and diseased tissues is of the essence of the operation, it adds enormously to the surgeon's difficulties. A further disadvantage lies in the fact that in many operations the anaesthesia is not established before the first incision is made, but it is necessary during the course of the operation to infiltrate the deeper layers, and often to wait some time for anaesthesia to develop. The operator's loss of time is not the only evil here, for, as every surgeon knows, it is of the first importance, in the interest of asepsis, that operations shall be performed quickly, and, if possible, without interruption of any kind. In small operations this is not of so great moment ; in the larger operative procedures, however, the certainty of maintaining asepsis undoubtedly diminishes as the duration of the operation increases. Finally, especially in the deeper regions, it is impossible to count with certainty on Schleich's dilute solutions for the efficient anaesthetization of the larger nerve-trunks. This is of special impor- tance in operations for ligature of bloodvessels, so that Schleich himself advises that in these METHODS OF LOCAL ANESTHESIA 63 operations the nerve-trunks running with the arteries shall be previously dabbed with 1 in 20 car- bolic acid. This is troublesome, and requires time. All this does not in any way diminish the great merit of Schleich's work. No investigator reaches at a bound the limit of the attainable in his line of discovery. As, however, we have to-day, as we shall see in the following sections, methods which are free from the disadvantages presented by Schleich's, the latter will only be employed when these other methods are for some reason inap- plicable. 4. "Conduction" Anaesthesia. This method, whose foundations were laid by Corning, has, during the last few years, acquired rapidly growing importance from the work of Hackenbruch and Braun. By the term " conduc- tion " anaesthesia we understand a method in which a given area of operation is rendered insensitive by anaesthetizing the sensory nerve-trunks passing from it, thus by interruption of sensory nerve- tracts. Two forms of conduction anaesthesia may be dis- tinguished : (1) that caused by perineural injection, in which the anaesthetic is injected into the neighbourhood of the nerve to be dealt with, and reaches the nerve by diffusion; and (2) that caused 64 LOCAL ANESTHESIA by injection into the nerve itself (endoneural). The latter is now hardly used, and we may confine our attention to the former. Of considerable importance here is the anatomi- cal fact that the smallest and finest branchings of the peripheral nerves possess only a very thin sheath, and that this increases in thickness as one passes along the nerve in a central direction, in proportion to the increase in calibre of the nerve itself. The thinner the sheath the more readily can anaesthetic solutions penetrate it to reach the nerve, interrupting the passage along the latter of sensory impulses. An important principle follows from the foregoing, namely, that it is more difficult to interrupt conduction in the larger nerve-trunks than in their peripheral branches. Whenever it is possible, therefore, to render insensitive the area of a projected operation by anaesthetizing the smaller nerve -trunks, this simpler method is adopted, and the larger nerves may be left out of account. The most frequently used method of this kind is the so-called " circular anaesthesia " of Hacken- bruch. Here the tissues surrounding the site of operation are thoroughly infiltrated with an anaes- thetic solution, and the conduction of afferent impulses thus cut off in all the sensory nerves supplying the area. Schleich's method of dealing with inflamed areas {e.g.y furuncles) is, in my opinion, in spite of METHODS OF LOCAL ANESTHESIA 65 Schleich's expression of the contrary view, merely a form of conduction anaesthesia. He begins by infiltrating the healthy tissues round the inflamed focus, and slowly, with intervals sometimes of minutes, continues the infiltration into the in- flamed parts. This is nothing more nor less than conduction ansesthesia, and the latter part of the procedure, the infiltration of the inflamed area, could quite safely be omitted, as it becomes anaesthetic, and often very rapidly, when the sur- rounding tissues are efiiciently infiltrated. The new substitutes for cocain, and the intro- duction of the suprarenin preparations, have enabled us to employ the method of circular anaesthesia much more freely than was formerly the case. A freer range of dosage is now permis- sible, stronger solutions and larger quantities may be employed than was formerly the case, and thus wider areas and larger nerve-trunks brought under the influence of the local anaesthetic. We inject now without misgiving as much as 50 c.c. of 1 per cent, novocain solution, while the quantity of cocain required to produce about the same eflect — viz., 50 c.c. of a 0'5 per cent, solution — is far beyond the limit of safety. Thus, for instance, the performance of an operation on strumous fj-lands under local anaesthesia, which was formerlv a diflicult and doubtful proceeding, is now simple, and as a rule absolutely safe. 5 66 LOCAL ANESTHESIA Where circular ancesthesia is applicable, we must endeavour to interrupt conduction in the larger nerve-trunks by perineural injection. In the case of some nerves this method is both simple and sure {e.g., nerves of the fingers) ; in others (nerviis alveolaris inferior), it is not simple, but when the technique is mastered, it is fairly sure. In others, again, as, for instance, the nerves of the forearm, it is not to be relied on, and is beginning to be re- placed by other methods. The best-known method of conduction anaesthesia by perineural injection is that bearing Oberst's name. It is used in opera- tions on the fingers and toes. After injection, which is carried out in the manner described below, the base of the digit is found to become anaesthetic first, the anaesthesia then gradually spreading towards the periphery. This fact might easily lead the unskilled observer to infer that the anaesthetic slowly diffuses in the bloodless member towards the periphery, and that the whole process is a centrifugal one. We know, however, that conduction of sensory impulses is much more readily interrupted in the finer than in the larger nerve-trunks. Thus the skin of the digital per- iphery, which contains the terminal ramification of the nerve-trunks which at the base of the finger are of substantial calibre, is the last to become anaesthetic, while the skin at the base is supplied by fine nerve-trunks running, at the point of in. METHODS OF LOCAL ANAESTHESIA 67 jection, side by side with the main trunks, and these lose their sensitiveness to pain very soon after the injection. Diffusion, as a matter of fact, plays but a small part in the development of this form of anaesthesia, as can be seen by noticing the whitening of the skin in a direction from centre to periphery, when a somewhat larger dose of supra- renin than usual is added to the anaesthetic. Ligature of the digit at the base is no longer necessary in Oberst's method. The finger can be anaesthetized with certainty by a 2 per cent, novocain solution + suprarenin. Endoneural injection is, as we have stated above, hardly employed at the present day. Formerly a certain number of major operations, especially amputations, were performed under it, the larger nerve-trunks being first exposed under Schleich's infiltration anaesthesia, and then directly injected with concentrated cocain solutions. This compli- cated method is now practically abandoned. Even before the introduction of Bier's venous ances- thesia, most surgeons chose in preference to it either general or spinal anaesthesia. In operations on inguinal hernias, a method introduced by Gushing has been frequently em- ployed, in which endoneural injections are admin- istered after exposure of the nerves of the inguinal region. This is now superseded by another method, in which the whole quantity of anaesthetic 68 LOCAL ANESTHESIA solution is injected before the commencement of the operation, and the operator is thus enabled to work quickly and surely. It is beyond, question that the method of con- duction anaesthesia possesses very real advantages over Schleich's m^ethod. As the chief of these I should place the possibility, especially in major aseptic operations, of carrying out the operation quickly and w^ithout anxiety about the anaesthetic, and, further, the completeness of the anaesthesia, and the fact that the parts operated on retain their normal anatomical conditions, and the operator is thus enabled to distinguish clearly the boundary lines of the different tissues. Another advantage is the lessened risk of injury to the tissues. There are, however, whole classes of operations to which the method of conduction anaesthesia is not applicable, and in which Schleich's method, generally somewhat modified, still holds its ground. 5. Venous Anesthesia. This latest advance in methods of local anaes- thesia was first described by Bier before the Surgical Congress of 1908. While, as we have seen, it is difiicult to anaes- thetize the larger nerve - trunks by perineural injections, owing to the thickness of their con- nective-tissue covering, Bier succeeded, by inject- METHODS OF LOCAL ANESTHESIA 69 ing ansesthetic solutions under pressure into the veins of a limb between two tourniquets, in securing the penetration of the solution into all the tissues of the involved area, including the protective sheath of the nerves, and this rapidly and with a completeness unknown under any previous method. Bier was able to demonstrate this experi- mentally on amputated limbs by injecting an indigo-carmine solution into the veins. Careful examination shortly after the injection showed that the tissues were traversed in every direction by blue tinted capillaries, even the bone marrow sharing in the general blue coloration. (Doubt was thrown at first on Schleich's statement that the bone marrow could be infiltrated by injecting the periosteum. The possibility, however, of infil- trating the medulla by way of venous injection proves the correctness of his observation.) In the living subject the section of the limb enclosed between the two tourniquets becomes anaesthetic almost immediately after the injection of the solu- tion (i per cent, novocain solution), under pressure (direct ancesthesia). Somewhat later the portion of the limb beyond the distal tourniquet also becomes anaesthetic (indirect ancesthesia). There is practically no risk of general poisoning in venous anaesthesia. The only untoward symptom observed by Bier has been nausea, which he has 70 LOCAL ANESTHESIA seen once in a child of seven and once in a woman of sixty after removal of the tourniquets. The doses employed: 60 to 100 c.c. of J per cent, novocain solution — are by no means large. Of chief importance, however, is the certainty that the novocain, being distributed to every part and tissue of the affected area, will enter into com- bination with the tissue protoplasm, and thus lose its poAver of causing general poisoning. Bier adopts special precautions only when he administers large doses to children. The pre- cautions he adopts are as follows : 1. After removal of the tourniquet it is re- applied for a time and then finally removed. This insures the passage of the drug in two portions into the general circulation, with an interval of time between. 2. The cannula, which is furnished with a stop- tap, is left in the vein until the operation is finished and it is time to apply the sutures. Warm physiological salt solution is then injected, so as to wash out any excess of the anaesthetic. How far there exist risks of injury to tissue which might contra-indicate the use of venous anaesthesia, only prolonged experience can show. In amputations for diabetic or senile gangrene Bier has several times observed abnormalities in the behaviour of the wounds which might possibly be ascribed to the anaesthetic. He therefore METHODS OF LOCAL ANAESTHESIA 71 advises against the use of the method in such cases. In one patient, a woman, motor paralysis of the hand followed an operation under venous anaes- thesia. The paralysis disappeared in the course of four weeks. Bier considered that the paralysis was of the same nature as that sometimes seen after adninistration of a general anaesthetic. The latter, however, only appears when the arm and shoulder iiave been kept during the operation in an abnormal position, such as would not occur or be maintained during venous anaesthesia. Air-bubtles have several times been seen in the veins. No symptoms of embolism, however, have followed their appearance. Out of lc'4 operations. Bier has had 115 good, 14 satisfactory results, and 5 failures. With increasing sureness of technique failures will gradually come to be avoided altogether. The direci anaesthesia, that, namely, affecting the section of the limb between the two tourni- quets, comes on immediately in the smaller and medium sized nerves. The saturation of the larger nerve-trunks requires some minutes (up to five minutes in tlie larger limbs). The more complete is the removal of blood from the parts involved the quicker is the development of anaesthesia. Irregularities in these respects are, however, observed occasionally. 72 LOCAL ANAESTHESIA The rapidity with which indirect angesth^ia — that affecting parts peripheral to the d/stal tourniquet — comes on varies very much. The onset may be almost immediate, or there rpay be a delay of as much as twenty minutes. Simul- taneously with the development of indirect anses- thesia there is noticed a weakness of the muscles, which is soon followed by complete paralysis. This motor paralysis is a sign that the indirect anaesthesia is complete, and that the Operation may therefore be begun. The deeper parts are, according to Bier, more rapidly involved in the anaesthesia tha^ the more suj^erficial. / The so-called indirect anaesthesia is a conduc- tion anaesthesia, determined by an interruption of conduction in the larger nerve-trunks. It spreads from the centre (distal tourniquet) to tlie periphery. Bier has abandoned the addition of suprarenin preparations. "While in some cases they had some effect in deepening and prolonging anaesthesia, in others they failed completely.* Petrow also has only occasionally noticed any prolongation of anaesthesia from the addition of suprarenin. The chief drawback to venous anaesthesia is its rapid disappearance (two to seven minutes) after removal of the tourniquets. This makes the arrest "^^ The uncertain eflfects of the earlier suprarenin prepara- tions may have been a factor here. ; METHODS OF LOCAL ANESTHESIA 73 of hsemorrhage a difficult process and its painless- ness not sufficiently certain. We may hope, how- ever, to succeed before long, perhaps with the aid of sujDrarenin preparations, in overcoming this difficulty. In any case venous anaesthesia represents cer- tainly an important step forward in the practice of local ansesthesia. On the one hand, certain operations which could only be carried out imper- fectly and with difficulty under conduction anaes- thesia {e.g., operations on the hand after perineural injections round the nerves of the forearm), can now be performed safely and surely under venous anaesthesia ; while, on the other, the larger opera- tions on the extremities — amputations, resections, etc. — have lost som.e of the dangers involved in general or spinal anaesthesia. Whether and to what extent special contra-indications will manifest themselves it is impossible now to say. It is probable that wider experience will show the necessity of using the method but sparingly where septic processes are present or the nutrition of the affected part is already interfered with. As a further disadvantage must be mentioned the somewhat complicated technique of venous anaesthesia. 74 LOCAL ANESTHESIA Arterial Anesthesia. For the sake of completeness mention may be made of some experiments of Goyanes and Oppel, who have brought about an arterial anaesthesia in animals by injecting cocain into the arteries. Oppel, for instance, found that he could inject eight to ten times as much cocain into the aorta as into the vena cava inferior, and deduces from this fact, fallaciously in my opinion, the superiority of arterial anaesthesia. The cocain is, he thinks, neutralized in the arterio-capillary area. Goyanes has twice employed this form of anaesthesia in the human subject. It is hardly probable that these experiments will lead to results of much impor- tance. Though the introduction of an anaesthetic into the arteries is in itself quite feasible, the situation of the arteries is such as to necessitate for that purpose a somewhat complicated pre- liminary operation, and it is for this reason un- likely that the method can compete seriously with the relatively simple method of venous anaesthesia. CHAPTER VI GENERAL TECHNIQUE Preliminary Remarks. In general, local anaesthesia should only be em- ployed in cases where it is possible to attain complete local insensibility to pain. This rule should only be departed from in cases of absolute necessity, that is to say, when general anaesthesia involves so great a risk to the patient's life as to forbid its employment. Everyone must expect failures at the commencement. The surgeon should candidly ascribe such failures to his own faulty technique or the imperfection of our methods, and should not seek forcibly to persuade his patient and himself that the former felt no pain. There are, of course, patients whose anticipation and fear of pain is such that they cry out and betray extreme excitement throughout an operation, and yet confess afterwards that they felt nothing ; for such patients local anaesthesia is unsuitable, and a general anaesthetic should be employed ; for the terror they endure during the whole pro- cedure must involve hardly less suffering than the 75 76 LOCAL ANESTHESIA actual pain of an operation. One must not be fanatical in one's advocacy of local anaesthesia. If it is not discredited by being used in unsuitable cases or by faulty technique, it will gradually gain in popularity, and cases such as that cited above will become rarer when patients can come to their surgeon for au operation with the absolute cer- tainty of the operation being painless. Even to-day patients frequently come to us with the request that they may be operated on under local anaesthesia, and not be rendered insensible by a general anaesthetic. Suggestions for a "combined anaesthesia," that is, for the auxiliary employment of a general anaesthetic during certain sj)ecially painful parts of the operative procedure, are, in my opinion, not to be commended. Here, again, exception may be made in respect of cases in which for special reasons narcosis must, as far as possible, be avoided. In such cases a brief ether or chloroform narcosis may be used in reinforcement of local anaesthetic methods, as for instance in a laparotomy, when at one stage traction must be made on the mesentery. Otherwise, one should allow the patient the assurance of an absolutely painless operation, and should avoid exaggerating the dangers of general anaesthesia. In passing to the consideration of general technique we would lay down at the outset, as a GENERAL TECHNIQUE 77 foundation principle, that it should be as simple as possible. We purposely avoid descriptions alike of complicated injection apparatus and of compli- cated anaesthetic solutions. The object aimed at is to describe methods in such a manner that they may be applied as readily by the practical coTintry doctor, as in a large surgical clinique furnished with every modern aux- iliary and appliance. The syringe I have found by prolonged trial to be most satisfac- tory is a glass syringe Avith a metal piston, which can be completely withdrawn from the glass cylinder. "'^' The syringe is boiled each time before use, either in water, physio- logical salt solution, or soda solution. In the latter case it must be washed through before use with sterilized water or salt solution, as soda irritates the tissues and lessens the effect of anaesthetic drugs, and ^^^- ^• especially of suprarenin preparations. Before boiling, the syringe must be taken apart. The cylinder must not, of course, be plunged suddenly into boiliug water, as this would involve great risk of breakage. From the moment boiling commences the parts should be left in the boiling water for five minutes. On withdrawal from the water the * The so-called '' Record " syringe. 78 LOCAL ANESTHESIA metal cylinder must first be cooled, otherwise it will be found impossible to introduce it into the cylinder. For those who only occasionally employ local anaesthesia syringes of 2 and 10 c.c. capacity are the most generally useful. Those who use it frequently should be sup- plied with syringes of 1, 2, 5, and 10 c.c. capacity. A supply of needles of various lengths and cali- bres should be at hand, including, perhaps, a few curved ones, though I have so far not found it neces- sary to employ the latter. The best are platino- iridium needles, which, though more costly than steel ones, are more dur- able, do not rust, and can be made red-hot without injury. It is, of course, a great advantage in practice that all his needles should fit every size of syringe used by the surgeon. After use all parts must be well dried and the needles washed through with absolute alcohol. It is advisable also to wash through the nozzle of the syringe in a similar manner in order to remove water completely. The needles should have a wire Fig. 4. GENERAL TECHNIQUE 79 passed through their barrel before being put away. It is advisable to smear the metal parts of the syringe with a drop of paraffin to prevent rust. For his method of venous anaesthesia Bier em- ploys a syringe of about 100 c.c. capacity (Fig. 4). It, too, has a metal piston working in a glass cylin- der. A thick-walled rubber tube can be fitted by a screw attachment to the nozzle of the syringe, the other end of the tube being connected with the in- jection cannula by a bayonet fastening. The whole apparatus is thus very readily put together and taken apart again. The injection cannula is fitted with a tap, which prevents leakage of solution. The cannulas employed are as thin walled as possible. Near their termination are two circular grooves to facilitate the process of tying into the vein. The syringe must be boiled only in physiological salt solution, not in alkaline solutions, otherwise the rules given above for the use and management of injection syringes apply here also. As regards solutions, it is advisable for any surgeon who operates much under local anaesthesia to have a supply of both 1 per cent, and 2 per cent, solutions of novocain in physiological salt solution always dt hand. The physiological salt solution is sterilized in ^ or 1 litre flasks, preferably in a water-bath, the flasks themselves having been previously steri- lized by boiling. The flasks are best closed by an 80 LOCAL ANESTHESIA india-rubber cork or a wad of sterile muslin. The novocain solution is kept in ordinary medicine bottles in quantities of 100 grammes, or, in the case of 2 per cent, solutions, of 50 grammes. Bottles and stoppers must be sterilized. The novocain solution is shaken up in the bottle, and the sterile physiological salt solution is added gradually ; the whole requires then only a short boiling in a water- bath. Before use, if one is not certain that the solution is still sterile, it should be heated to 100° C. in a water-bath for five minutes, or the required quantity can be raised to boiling-point in a sterile test-tube. The amount required for use is then poured into a sterilized graduated glass cylinder of about 50 c.c. capacity, and from this into a sterilized glass dish (all, of course, boiled in soda-free solutions). Suprarenin is added imme- diately before the solution is to be used. It is kept only in small bottles holding 5 c.c. Supra- renin solutions that are not absolutely clear should on no account be used. It is advisable also to re- ject any bottles that have been kept for any con- siderable time since opening. After the first use the rubber stopper should be replaced by an ordinary cork. In the case of major aseptic opera- tions it is better to take the solution from a previously unopened bottle. Those who make only occasional use of local anaesthesia will find Braun's novocain suprarenin GENEKAL TECHNIQUE 81 tablets suitable and useful. They are simply dis- solved before use in a given quantity of sterile physiological salt solution. Any of the solution that may remain over after use should be thrown away ; it should on no account be used again. I personally prefer to add the suprarenin imme- diately before the operation, as I have several times observed a rose tint to develop on dissolving the tablets in warm water. Two tablets are manufactured : Tablet A. Novocain, 0'1:^5 gramme; suprarenin, O'OOOIG gramme. This tablet dissolved in 5 c.c. gives 5 c. c. of a 0*25 per cent, novocain solution -1-5 drops of suprarenin (Solution L). Twenty-five c.c. gives 25 c.c. of a 0'5 per cent, novocain solution 4-5 drops of suprarenin (Solu- tion 11. ). Tablet B. Novocain, O'l gramme; suprarenin, '00045. This tablet dissolved in 10 c.c. gives 10 c.c. of a 1 percent, novocain solution + 10 minims of supra- renin (Solution III.). Five c.c. gives 5 c.c. of a 2 per cent, novocain solution + 10 minims of suprarenin (Solution IV.). 6 82 LOCAL ANESTHESIA Solutions II. and IV. can be obtained ready prepared in small bottles or ampullae, and Solu- tions I. and III. can be prepared by simple dilu- tion with an equal volume of physiological salt solution. It is still a disputed point whether or no the tablets are sterile. Until just recently it has been impossible to boil their solutions, as the suprarenin they contain is not the synthetic form. Lately, in view of the fact that the ready decom- posibility of the suprarenin is due to the presence of traces of alkali (in the glass vessels ?), Braun has recommended that officinal dilute hydro- chloric acid be added to the physiological salt used for dissolving the tablets, in the proportion of 1 minim to the litre. The solution can then safely be boiled before use. To dentists who employ almost always the same strength of solution, ampullae containing 1 c.c. of 2 j)er cent, novocain solution + 1 minim of supra- renin may be recommended as useful and con- venient. The 1 per cent, solution of novocain is the one I generally employ in minor surgery. The 2 per cent, solution is only used for interrupting con- duction in nerve-trunks of some size, especially in operations on the teeth and fingers. In all opera- tions in which more than 50 c.c. of the solution has to be injected I use the O'o per cent, instead of the 1 per cent, solution. If more than 100 c.c. is GENERAL TECHNIQUE 83 required, I make the additional infiltration with 0*25 per cent, solution. Of suprarenin — I always use the 1 in 1,000 solution of Suprareninum L. Syn- theticum — I add, in most operations, 1 to 4 minims to each 10 c.c. of the anaesthetic solution, fixing the maximum quantity of suprarenin to be injected at from 15 to 20 minims. Only where large nerve- trunks have to be anaesthetized do I add a larger percentage of suprarenin to 2 per cent, anaesthetic solutions — e.g., from 1 to 2 minims to each cubic centimetre. As only small quantities of solution are here employed, this larger percentage of supra- renin may be added without misgiving. When, in the following pages, nothing is said about the dosage of suprarenin, the rules already laid down on the matter must be taken as apply- ing. Those more practised in local anaesthesia will not, however, follow them too rigidly, but will suit the dose to the individual case in accord- ance with the amount of blood in the tissues, the nutritional condition of the latter, and so on. If the method of Schleich is carried out rigidly and the tissues so thoroughly infiltrated in layers that they appear to have undergone a simultaneous soakage, it is advisable either to omit the addition of suprarenin altogether, or to add only small doses (1 minim to 10 c.c. as a maximum), as the anaemia caused by the artificial cjedema acts as an auxiliary to the anaesthetic. In small operations 84 LOCAL ANESTHESIA one may use 0*5 per cent, novocain solution with confidence. For larger operations 0*25 per cent, solution should be employed. It is, however, often advisable to modify slightly Schleich's technique, and avoid producing a maxi- mum degree of oedema, though the tissues should always be freely permeated by the injected solu tion. In small operations we then employ 1 per cent., and in larger 0*5 per cent., solutions, with or without the addition of the dose of suprarenin given above. It is not then necessary to dab the larger nerve-branches specially with phenol solution ; the concentrated novocain solution will soon render them anaesthetic, though a certain time must always be allowed for this effect to develop. We shall also, when the infiltration method has to be employed, infiltrate as many of the tissue layers as possible before the operation, wait for a time, and then carry out the operative procedures, if possible, without a break. A thorough infiltration of the subcutaneous cellular tissue renders super- fluous any special infiltration of the skin itself. In conduction ansesthesia, also, it is often advis- able to infiltrate the tissues pretty thoroughly wath anaesthetic solution. This, how^ever, does not apply in the case of ana3sthetizafcion of the larger nerve-trunks by concentrated (2 per cent.) solutions. While in Schleich's method the opera- tion is commenced immediately after the infiltra- GENERAL TECHNIQUE 85 tion of the tissues, in conduction an aesthesia, on the other hand, some considerable time must often be allowed to elapse between the comple- tion of the infiltration and the commencement of the operation, it being essential to success in this method to wait a sufiicient time to allow of the development of a completely anaesthetic con- dition. Many a failure is to be attributed to the impatience of the operator. There need be no fear of letting the right moment pass, for the anaesthesia produced with the aid of suprarenin lasts a considerable time. No general rule can be laid down as to the time that must be allowed after the injection. This depends on the calibre of the nerve-trunks involved, the strength of the solution used, and other factors. Often, especi- ally in small operations on the face or head, complete anesthesia becomes established almost immediately after the injection. After injection in the neighbourhood of the inferior alveolar nerve it is often necessary to wait half an hour for the onset of anaesthesia. It is, for reasons already given, especially important to avoid, if possible, injecting into inflamed tissues. Occa- sional exceptions to this rule will be considered later. As regards the technique of the actual injec- tion, the risk, though a slight one, of injecting into a vein must be kept in mind. It is a good 86 LOCAL ANESTHESIA plan to move the needle backwards and forwards continually during the injection. The syringe may be withdrawn from the needle after the puncture is made, and the operator may thus assure himself that no blood passes out through the needle. Technique of Bier's Venous Anesthesia. The solution is injected into a vein lying in a section of a limb, which is cut off from the general blood-stream by two tourniquets. The tourniquets may, for example, be applied above and below the elbow-joint, and the injection be made into the vena basilica at the level of the joint. The part of the limb between the tourniquets must be rendered as bloodless as possible. As a rule the blood is expelled from the limb by an Esmarch bandage, applied up to the level of the central tourniquet. If, owing to the presence of an infectious process, this is not possible, the peripheral tourniquet is a|)plied above the infected area, and the blood then expelled from the level of the peripheral to that of the central tourniquet. The central tourniquet is applied a little above the area of operation, and is not bound more tightly round the limb than is necessary. The pressure of the tourniquet is not as a rule GENERAL TECHNIQUE 87 unpleasantly felt after the injection. We have, however, known patients to complain of the pressure throughout the operation. It is advis- able, therefore, to inject at a point as near as possible to the upper (central) tourniquet ; the vein may also be exposed before the tourniquets are applied. The tourniquets are kept in phenol solution after aseptic operations, otherwise they are sterilized by boiling. The exposure of the vein is carried out under infiltration ana3sthesia with the same 0*5 per cent, solution that is used for the injection. If the search for the vein is carried out before the parts have been rendered bloodless, it is advisable to add a little suprarenin to the solution. The subcutaneous cellular tissue must also in this case be thoroughly infiltrated. If the vein is sought for under bloodless conditions, its position, rendered plain by obstructing the venous flow, must be marked before the tourniquet is applied. A diagonal incision is made through the skin. In obese subjects the vein is often concealed by masses of fatty tissue. When the vein is ex- posed, a silk thread is passed round it by means of a Deschamps' needle, and the vein thoroughly exposed and freed for a distance of about 2 centi- metres. If there is much scar formation, the vein must, in view of the possibility of obliteration, be sought for well above the scar. In the leg the 88 LOCAL ANAESTHESIA N. saphenus Fig. 5. Fig. 6. Course of the Veins in the Lower Extremity, GENERAL TECHNIQUE 89 V. basilica and N, cutaneus antebrachii V. mediaiia great saphenous vein is the one most frequently injected in practice (Figs. 5 and 6). ^.. Its course is depicted in the figure. It arises from the middle of the venous network on the dorsum of the foot, and then passes in front of the inner malleolus to the inner side of the leg, where it is accom- panied by the saphenous y. cephaiica nerve. It then runs along the inner side of the knee- joint, passing behind the inner condyle of the femur, after which it again comes forward, coursing along the inner and anterior surface of the thigh to the saphenous opening, where it ends in the femoral vein. In the arm (Fig. 7) the veins used as a rule for injection are the cephalic and basilic veins in the lower half of the arm. The por- tion of the cephalic vein with which we are concerned lies, ac- cording to Bier, in front of the sulcus bicipitalis lateralis, on the outer side of the biceps. The Vjasilic vein lies in the sulcus hicipi- talis internus ; the accompanying nervus cutaneus Fig. 7. — Course OF THE Veins IN THE Arm. 90 LOCAL ANESTHESIA antebrachii must be kept in mind. The median vein {yideY\g. 7) is, according to Bier, not well adapted for direct anaesthesia, especially for operations on the elbow-joint. While the deeper parts are quite insensitive, there is always, just peripheral to the central tourniquet, a cutaneous area which is not anaesthetic, and this area is larger the more peripheral the site of injection (Figs. 8 and 9). The injection must there- fore be made as close up as possible to the central tourniquet. For indirect anaesthesia (vide pp. 69, 72) the median vein is quite suitable. To return to the technique, the vein having been exposed and a ligature passed round it, it is drawn u^) by means of the ligature into the upper angle of the wound. A second ligature, peri- pheral to the first, is then passed round the vein, into which an incision is made with a fine pair of scissors between the two ligatures. The needle or cannula is now passed carefully into and along the vein in a peripheral direction — injection in a central direction has occasionally been followed by symptoms of poisoning — and the peripheral ligature is tied round the vein and cannula, the latter being then withdrawn until the ligature, which is drawn somewhat tight, slips into its groove (vide p. 79 and Fig. 4). The ligature is then securely tied, and its security tested by gently drawing the cannula backwards. GENERAL TECHNIQUE 91 The 0'5 per cent, solution at blood-heat is then injected (maximum quantity 100 c.c), the vein being held sightly tense during the injection. Many patients find the inflow of the solution, Fig. Fig. Extent of Venous Anjesthesia according to Site of Injection. which causes a swelling of the aflected section of limb proportional to the amount injected, some- what unpleasant. Bier has on two occasions found, when operat- 92 LOCAL ANESTHESIA iiig on the forearm, that the valves of the veins have acted as an obstruction. In both cases he was able finally, by the exercise of considerable pressure, to overcome the resistance. After the injection is completed, the vein is ligatured above and the small wound attended to at once. As a general rule direct anesthesia should be employed (vide wfra). According to Bier 80 c.c. of solution will almost always be found sufficient. CHAPTER Vir METHODS FOR ANESTHETIZING THE SKIN AND THE DIFFERENT TISSUES — PROCEDURE IN CERTAIN DISEASED CONDITIONS — CIRCULAR ANALGESIA The skin is an organ extraordinarily sensitive to pain, the most sensitive, in fact, of the whole body. In the degree of this cutaneous sensibility to pain, however, different parts of the body differ from each other very widely. The least sensitive cuta- neous areas are probably those of the back and the abdomen, the most sensitive those of the nose and ear, and the flexor surface of the fingers and hands. In these respects, also, however, there are wide differences between individuals. The skin may be rendered insensitive either by terminal or by conduction anaesthesia — that is to say, by anaesthetizing either the sensory " end- organs" in the skin, or the terminal sensory nerve-tracts which convey sensory impulses from those end-organs. In the first method, usually given Schleich's name of " wheal aniesthesia" {Quctddelandsthesie), 93 94 LOCAL ANESTHESIA the solution is injected endermally by means of a fine hollow needle. In making the puncture a fold of skin should be pinched up where this is possible, and the needle inserted parallel to the cutaneous surface. A white insensitive wheal is then seen to form immedi- ately after the solution is injected. The needle must be kept in the skin itself, and must not be allowed to pass into the subcuta- neous cellular tissue. Often, if the skin is elastic and not too thin, the needle may be pushed forward endermally, so as to anaesthetize an area of skin of considerable length. As a rule one must be satisfied with making as large a wheal as possible, and then making another Fig. 10.— Wheal Anesthesia puncture within the area, but near the edge, of the first wheal, which is now anaesthetic {vide Fig. 10). The first puncture may be rendered painless by the use of ethyl chloride. If, however, a fine METHODS FOR ANAESTHETIZING THE SKIN 95 needle is used, the pain of the puncture is very slight. A 0*25 per cent, novocain solution, with a small dose of suprarenin added, is quite sufficient for longer operations. In minor operations re- quiring stronger (0*5 or 1 per cent.) solutions, however, small areas of skin can be safely anaesthetized with these solutions. A larger dosage of suprarenin is not, in my opinion, advis- able in this form of anaesthesia. As the pressure- oedema helps to intensify the anaesthesia, small doses of suprarenin (at most 1 minim to each 10 c.c. of solution) are sufficient to increase the duration and intensity of the anaesthesia without risk of injury to the tissues. The area infiltrated in the above manner is but a narrow one, and the anaesthesia does not extend much beyond the borders of the wheals themselves ; it is important, therefore, that in suturing at the end of the operation the stitches should be inserted within the zone of infiltration. Nowadays the skin is generally anaesthetized by conduction anaesthesia from the subcutaneous cellular tissue. This does not, like the skin, possess sensory end-organs, but only terminal sensory nerve-tracts, for the skin or organs situated imme- diately beneath it (glands), and, e.g., in the head, also sensory fibres, which penetrate the fasciae towards the deeper parts and suppl}^ the peri- osteum. 96 LOCAL ANESTHESIA In this method the subcutaneous cellular tissue is infiltrated from two opposite points, chosen with reference to the position and extent of the area to be anaesthetized, generally with 0*5 or 1 per cent, novocain solution and suprarenin, and an anaes- thesia of the overlying skin area then develops. The rapidity of its onset is dependent on various circumstances. Thus where, as in the scalp, the injection causes a bulging outward of the skin, anaesthesia comes on quickly, often immediately. Where, on the other hand, the subcutaneous cellular tissue is very rich in fat, as in the gluteal region, considerable quantities of concentrated solutions, large additions of suprarenin, and a long period of waiting, are often required before a con- dition of anaesthesia can be attained. In many operations it is preferable to inject the subcuta- neous cellular tissue, not underneath, but around the line of incision, so that the surgeon will be able afterwards to operate in tissues in a normal condition. The foregoing rules apply also to the anaestheti- zation of the subcutaneous cellular tissue itself. Anaesthesia of mucous membranes is brought about either by "painting" the mucous surface with the anaesthetic solution, or by conduction anaesthesia, as just described in the case of the skin. In the latter case the first incision may be ren- dered painless by the previous application of 10 per METHODS FOR ANESTHETIZING THE SKIN 97 cent, phenol solution (Schleich's), or of 10 per cent, novocain solution. It is important not to employ too dilute solu- tions. As above stated, the 1 per cent, solution of novocain is • the best for all minor operations. This solution very soon interrupts conduction of sensory impulses, even in the larger nerve-branches which traverse the subcutaneous cellular tissue, so that prolonged waiting is unnecessary. Let us take a concrete example, for instance, the excision of a lupous focus in the face. The con- duction of sensory impulses from the diseased area is to be thoroughly interrupted without infiltrating the area itself. In the first place the subcutaneous cellular tissue in the neighbourhood of the focus must be infiltrated from two, or, if the diseased area be a large one, from four, injection points a few centimetres outside the operation area, with 1 per cent, novocain solution + suprarenin. This will interrupt the conduction of sensory impulses in most of the nerve channels supplying the area. It is a good plan to render the injection points insensitive by the method of " wheal " anaesthesia, so that the subsequent injection with a larger needle may be painless. In many cases the injec- tions above described suffice. Often, however, the affected area is also supplied with sensory nerves which reach it from the deeper parts. Besides this, nerve- trunks often traverse the subcutaneous 7 98 LOCAL ANAESTHESIA cellular tissues for considerable distances, and these will be of notable calibre at the points of injec- tion. In order to interrupt conduction in these also it is necessary to infiltrate the subcutaneous cellular tissue immediately underneath as well as that surrounding the diseased focus. We have then the most commonly employed form of local anaesthesia, the so-called circular analgesia of Hackenbruck — i.e., the disconnection of an area of operation by circular interruption of all sensory nerve-channels supplying the area. The method is applicable to the great majority of diseased conditions necessitating operations on the skin or subcutaneous cellular tissues, furuncles, tumours, foreign bodies, lymphadenitis, etc. The peripheral parts of the area are the first to become anaesthetic, the nerves supply- ing the central portions being ''caught," so to speak, by the anaesthetic at a greater distance from their terminations, and being, therefore, of larger calibre than those supplying the periphery. Diffusion phenomena also play a part in the matter, as is often made plain by the spread of a whitish tint from the periphery towards the centre. Difiiculties may arise in cases where nerves of considerable calibre pass direct from the deeper tissues to the diseased organ. Thus it is often difficult to render completely painless an opera- tion for the extirpation of inflamed inguinal glands. METHODS FOR ANAESTHETIZING THE SKIN 99 The boundary of the possible area of circular anal- gesia is here placed where the inflamed area and the underlying tissues join, so that it is impossible to inject beneath the focus and thus completely interrupt the sensory conduction. An exception is formed where subcutaneous nerves j^ass through the fascia to the deeper tissues and supply periosteum and bone — e.g., on the scalp. Other- wise we must in these cases either ansesthetize the larger nerve-trunks where we can reach them, or — as, for instance, in an extirpation of inguinal glands, where the mass is in intimate connection with the underlying tissues — we must, after sub- cutaneous injection, proceed to infiltrate succes- sively with a large amount of anaesthetic solution the tissues through which the surgeon will have to make his incisions. Often, when it is not essential to render insensitive the whole diseased area — as, for instance, in a parulis which is "point- ing" — we merely infiltrate by Schleich's method the line of incision. We can generally do this painlessly in spite of our rule against infiltrating inflamed tissues, as the existing oedema has lowered the sensibility of the parts, and, secondarily, in- flamed skin is often less sensitive than that attacked by a primary inflammation. No wheal is formed in this case, but the solution diffuses itself through the relaxed tissues, and must be injected in con- siderable quantity. Where, then, we have an 100 LOCAL ANESTHESIA area of oedematous and only secondarily affected skin overlying inflamed parts, it is often possible to infiltrate those parts painlessly without previous injection of surrounding sound tissues. The matter is still more simple in the case of a small incision or puncture of an abscess, if the skin and other covering tissues are quite sound. It is only neces- sary to inject continuously, as the needle is passed on through the overlying tissues, in order to render the whole path of the puncturing instru- ment anaesthetic. All the more important is it, however, in inflammations of the skin itself, such as boils and carbuncles, to avoid infiltrating inflamed parts until they have been rendered anaesthetic. This is only likely to present diffi- culty when the inflammation extends into the deeper-lying parts, as, for instance, in the case of a large cervical carbuncle. In such a case we must, following Schleich's practice, infiltrate the tissues step by step, starting in sound tissues, and only after the onset of anaesthesia (which is quite rapid if 1 per cent, novocain solution is employed) continue the injection till the whole diseased focus has been surrounded. Otherwise, when several layers of tissue have to be infiltrated, the rule of infiltrating the deeper layers first, holds good. The foregoing applies, of course, also to super- ficial tumours. Malignant tumours, however, should not be operated upon under local anaes- METHODS FOR ANESTHETIZING THE SKIN 101 thesia, in the absence of a clear demarcation between the cancerous and the healthy tissues. If the cancerous growth has attacked the surround- ing parts, and especially if the neighbouring glands are involved, operating under local anaesthesia cannot be too strongly deprecated. General anaes- thesia is here avoided at a heavy cost, radical removal of the tumour and of its metastases in the neighbouring glands being impossible without it. In the case of innocent tumours intimately attached to the underlying tissues the method above described, as applicable to the extirpation of inguinal glands, may be recommended. First free injection around the diseased glands, the dis- secting out being continued under Schleich's infil- tration method. It is particularly important to secure complete anaesthesia when operating for the removal of foreign bodies. Every surgeon of experience in this matter knows how frequently unpleasant surprises are experienced. It is often necessary, especially when the foreign body is situated deeply in the substance of a muscle, to bring Schleich's infiltration method to one's aid. As regards other tissues of the body, it should be noted that tendons are insensitive, while the tough, connective tissue surrounding them and their sheaths has, on the contrary, a high degree of sensibility to pain. Muscle fasciae, or apo- neuroses, are also in most parts sensitive. As a 102 LOCAL ANESTHESIA rule, therefore, it is sufficient, in order to render tendons and fasciae anaesthetic, to infiltrate the surrounding connective tissue. Local anaesthesia is not suitable for operations on tendons involved in cicatricial tissue, unless a pure conduction anaesthesia can be employed. Muscles behave in much the same way as the subcutaneous cellular tissue. Broadly speaking, their substance is insensitive to pain. They are, however, traversed in many parts by sensory nerves, interference with which causes pain. Small scars, or sclerosed centres in muscle, are particu- larly sensitive. Muscles should be freely infil- trated, and usually, following Schleich's practice, with not too dilute solutions. Schleich himself has often used 0*5 j)er cent, cocain solutions. It is necessary to wait a few minutes for the full development of anaesthesia. Divergent views prevail as to the sensibility of the periosteum. The truth of the matter would appear to be that in some regions the periosteum has no sensibility, while in others it is, on the contrary, extraordinarily sensitive to pain. The bones are as a rule supplied with sensory nerves from the periosteum. If the periosteum be elevated from the bone, the outer uncovered surface of the latter is insensitive. The medulla of bone, however, exhibits, according to Schleich, sensi- bility to pain. Thus it has been repeatedly observed METHODS FOE ANESTHETIZING THE SKIN 103 that in amputations carried out under local anses- thesia the whole operation is painless, except the sawing through of the bone. This is probably to be explained by the fact that nerves traverse the substance of bones for considerable distances, and as the periosteum is, in practice, only elevated for a short distance, the medulla, at the given point, con- tains sensory nerves, which have passed from the periosteum to the bone at points central to the line of amputation. Ansesthetization of bone and perios- teum is brought about with the most facility where we are able to induce anaesthesia by interruption of conduction in superficially situated nerve-trunks, as, for instance, in the fingers, the scalp, or the lower jaw {nervus alveolaris inferior). In flat bones injections must be made around the affected area at as deep a level as possible {e.g., focus in sternum). Finally, in the case of many hollow bones — as, for instance, in resection of ribs — we must inject all round the whole area of bone which we wish to anaesthetize. If this is done thoroughly, it is sufficient if the needle be passed down close to the periosteum, and it is not neces- sary to proceed to an actual subperiosteal infiltra- tion. As stated above, the deeper layers are always injected first, and then the subcutaneous tissues. For cartilage and perichondrium the same rules apply as for bone and periosteum, both as regards 104 LOCAL ANESTHESIA sensibility to pain and the best methods of pro- ducing ansesthesia. As regards articular capsules, ligaments, and synovial membranes, though the opposite opinion has been expressed, Braun's view is undoubtedly correct, that these possess a somewhat high degree of sensibility, which, as is the case also with all the tissues we have considered, is very much increased in inflammatory conditions. In major operations on the larger articulations, as also in many operations on the large tubular bones of the extremities, venous anaesthesia is likely soon to displace other methods. In simple puncture of a joint the same procedure is adopted as for the puncture of abscesses. If an irritant substance has to be injected into a joint, the latter is first freely injected with 0*5 per cent, novocain solution + suprarenin. After the lapse of a period of five to ten minutes the joint is entirely insensitive. The ansesthesia can be tested by moving the trocar, which has been left in situ, backwards and for- wards, and when found to be complete the medicament should be injected at once. CHAPTER VIII OPEEA.TIONS ON THE HEAD 1. Operations on the Scalp and Forehead. As already stated, the scalp is a specially favour- able region for the application of local anaesthesia, inasmuch as the nerves, running for considerable distances under and parallel to the skin, ultimately, after passing through the fascia to the deeper tissues, innervate the bones of the skull and their periosteum, so that it is easier here than in most other regions of the body to bring about an anaes- thesia of bone by subcutaneous injections. The usually small development of fat in this region is also favourable to the attainment of an anaesthesia on which one can rely. A glance at Fig. 11 shows the course of the nerves, and makes it clear that near the points of exit of the nerves it is possible, without circular injection, and merely by subcutaneous injection of a strip at right angles to the course of the nerve, to bring about anaesthesia of a given area. This carmot, however, be recommended as a general 105 106 LOCAL ANESTHESIA practice, in view of the existence of occasional irregularities in the course of the nerves. The method is most to be depended on when applied to the frontal region. In general, however, circular injection alone gives certainty of the Fig. 11. — Course of the Sensory Nerves of the Face (Braun). 1, N. frontalis ; 2, N". supraorbitalis ; 3, N. zygomat. temporalis (Trigem. II.) ; 4, N. auriculo-temporalis (Trigem. III.) ; 5, N. auricu- laris magnus ; 6, K. occipitalis minor; 7, N. occipitalis major; 8, N. supra- and infra-trochlearis ; 9, N. infraorbital is ; 10, R. nasalis ext. N. ethmoidalis ; 11, N. mentalis. attainment of a complete anaesthesia. It is, how ever, not as a rule necessary on the scalp or fore- head — in view of the general course and distribu- tion of the nerves above described — to pass the injecting needle beneath the affected area, it OPERATIONS ON THE HEAD 107 being generally sufBcient to make one's injections around the area of operation in the form of a circle or rhombus. The necessary first treatment of head injuries, even of those involving severe injury to bone, can be carried out under this method most satisfactorily. The parts surround- ing the injury are dry- shaved, the skin near the wound is painted with tincture of iodine, the anaesthetic solution is injected, and the area of operation is then further prepared by cleansing with ether or benzine. If the dura mater is met with in the course of the operation, no harm is done, as the injections will have rendered it insensitive by interrupting conduction in its sensory nerves. My experience in a good many operations entirely bears out Braun's statements in this regard. Cases have been recorded, however, by other observers in which the dura retained its sensibility. The surface of the brain, however, seems to be quite insensitive, the fact having been established by numerous recorded observa- tions on the living subject. Trephining operations, therefore, especially where there is no large amount of muscular tissue beneath the galea, are specially suitable for local anaesthesia. Supra- renin is here of great utility. In the proportion of 1 minim of synthetic suprarenin to 10 c.c. of solution it causes a sufficient degree of ansemJa, and renders superfluous Heidenhain's method of 108 LOCAL ANESTHESIA ligation. Where, in view of the large area of the field of operation, very large quantities of solution have to be employed, the suprarenin may be given in still more dilute proportion. It has also been recommended in operations under general anaes- thesia that, instead of ligation, a dilute suprarenin solution should be injected with a view to the prevention of haemorrhage. I have obtained a thoroughly satisfactory local anaemia after injec- tion of 1 minim of suprarenin to 20 c.c. of solution. Heidenhain's method, however, must be regarded as that which involves least risk of doing harm. To what extent local anaesthesia will secure adop- tion in larger operations on the skull the future alone can decide. It is, however, not everyone who can bring himself to let his skull be chiselled open while he is fully conscious. One of my patients told me that, though he suffered no pain, the sensations of hammering and boring were so horrible that he would much prefer to be put under chloroform. Such points must be borne in mind, in the absence of some very compelling ground for avoiding general anaesthesia, and the boon of unconsciousness should not be denied such patients. The foregoing applies only to those parts of the head in which the periosteum lies immediately under the galea, so that other tissues are not in question. If the operation is to be performed on a OPERATIONS ON THE HEAD 109 region nearer the face, a careful circular injection must be carried out. Where muscles are situated between the skin and the bone {e.g.^ maxilla temporalis), these also must be carefully infiltrated. If two dilute solutions are not employed, which is seldom necessary here, where large quantities of solution are hardly ever required, a reliable anaesthesia can be attained in any part w^ithout paying too close attention to the exact points of exit of the superficial nerves. In trephining the frontal sinus, injections are made, first deeply and then subcutaneously, around the point where the trephine is to be applied. The trephining can readily be made painless. The mucous membrane of the sinus, however, is supplied by the ethmoidal nerve, which passes from the orbit. As an interruption of conduction in this nerve is hardly practicable, necessary manipulations of the mucous membrane must be rendered painless by the application to it of a concentrated solution — 10 per cent, novocain solution + suprarenin. The method is not very satisfactory, and where it is necessary to go beyond the mucous membrane the case is quite unsuitable for local anaesthesia. no LOCAL ANAESTHESIA 2. Operations on the Face. The rules already laid down for anaesthetizing the skin and subcutaneous cellular tissue will as a rule be found sufficient in the case of operations on the soft parts of the face, such as incisions of furuncles, removal of tumours, plastic operations, etc. If 1 per cent, novocain solution is employed, it is hardly necessary to pay minute attention to the points of exit of the nerves through the fascia, though, should such a point come within the area of operation, a somewhat more copious infiltration may be made in its neighbourhood. Large quantities of solution are not generally required, so a few extra cubic centimetres may be used in this manner without misgiving. The dose of suprarenin need not be large for operations in this region. From 1 to 2 minims of synthetic supra- renin to each 10 c.c. of solution, according to the amount of fat in the subcutaneous cellular tissue, is generally sufficient. In a large number of operations injection around and underneath the affected area will suffice. Of the treatment suit- able in extensive superficial morbid processes, a concrete example has been given above in the description of the methods to be applied in a case of lupus of the cheek. Should the focus be attached to the subjacent tissus — e.g., should it be adherent to the surface of the superior or inferior OPERA.TIONS ON THE HEAD 111 maxilla — the circular injection of the subcutaneous tissue must be preceded by a similar injection of the deeper layers immediately above the perios- teum. Here, however, should the area of opera- tion include a point of exit of one of the nerves, it will be necessary, after the incision of the skin, to inject a small quantity of solution into the larger divisions of the nerve. In operations on the eyelids it is sufficient, in the case of either eyelid, to infiltrate along the line of the corresponding bony border of the orbit. 3. Operations on the Eae.^ With regard to the distribution of sensory nerves to the ear, the following points should be borne in mind : The pinna and external auditory meatus are supplied — 1. By the auriculo-temporal nerve. 2. By the auricular branch of the vagus. 3. By the great auricular nerve. The nerves, for the most part, pass to the meatus from in front and from below (vide Fig. 11). In operations on the pinna it is generally suffi- * Privat-docent, Dr. Haike kindly assisted me in the pre- paration of this section, as also of that dealing with operations on the nasal and oral cavities. 112 LOCAL ANAESTHESIA cient to interrupt, by a subcutaneous infiltration, the conduction of sensory impulses from the part to be dealt with. Very small quantities of solu- tion suffice here, as the skin rises immediately in a wheal -like manner after even a small injection. If the whole pinna is to be anaesthetized, all that is necessary is to infiltrate subcutaneously in a circle immediately around it with 1 per cent, novocain-suprarenin solution. As a final pre- caution, it is advisable to inject deeply an extra 2 or 3 c.c. where the larger branches pass to the ear — that is to say, behind the lobe of the ear and in front of the mastoid process. For operations on the external auditory meatus reliance is often placed on the application of a plug of cotton- wool saturated with a solution containing — Parts. Ac. carboL liq. ... ... ... 5 Cocainae hydrochlor. ... ... ... 2 Menthol 2 8p. vini. Teat. ... ... ... ... 10 The most frequently required operation in this region — the incision of boils— is certainly rendered less painful by this application, but is by no means painless. For operation on the bony walls of the meatus the method is, of course, quite useless. The method advocated by Eichen and Braun for opera- tions on the meatus will probably gradually secure OPERATIONS ON THE HEAD 113 wider adoption. Its aim is to amvsthetize, by interruption of conduction, the nerves above de- scribed as supplving the external meatus. Solution of novocain (1 per cent.) + su}U'arenin is first freely injected behind the lobe of the ear in the depression in front of the mastoid j^rocess, the needle being passed deeply in along the lower border oi' the auditory meatus ; a second injection is made in a rather more anterior position, and the neighbourhood of the anterior wall of the meatus is thus intiltrated with the same solution. After live minutes the anaesthesia is as a rule com- plete. Ditiiculties occasionally arise, as, for instance, in furuncles, when the intlammation has spread pos- teriorly to the adjacent parts. In view of the extreme sensitiveness of the parts, it is necessarv to proceed slowly from tiie healthy to the diseased, injecting gradually more and more deeply. The membrana tympani is partly supplied by the nerves above mentioned ; in part, however, as is also the case with the middle ear, it is su[>plied by sensory fibres from the glosso- pharyngeal and vagus nerves, in whose case, of course, an inter- ruption of conduction is out of the question. By instillation of the above-n\entioned phenol- cocain solution the sensibility of tlie membrana tympani can be considerably diniinished. A \Aed- li'et oi' cotton-wool soaked in the sohition shouKl 114 LOCAL A^^STHESIA also be pressed against the point involved until the latter becomes whitish. The carbolic acid renders the epidermis more permeable by the anaesthetic solution. As, however, the solutions diffuse only very imperfectly through the epithe- lium of the membrana, the results are not alto- gether satisfactory. Two methods have been introduced recently : Tiefenthal takes 4 minims of 20 per cent, cocain solution + 1 minim of suprarenin, allows this quantity to act upon the membrana tympani for fifteen minutes, and then injects 2 to 4 minims of cocain-adrenalin solution (5 to 10 per cent.) through the drum at its lower part into the middle ear. Rupprecht kneads a piece of alypin about the size of a bean with 2 minims of sujorarenin, covers the upper half of the drum with the mixture, and leaves it to act for fifteen or twenty minutes. According to E;upprecht, the osmotic difference between the mixture in contact with the drum and the lymph of the middle ear facilitates diffusion through the somewhat impermeable tympanic epithelium. Both authors, however, admit that their methods do not give a thoroughly trustworthy anaesthesia. It must be remembered that often, when the ear-drum is near the ]3oint of j)erforation, the amount of pain caused by attacking it is minimal : OPERATIONS ON THE HEAD 115 this may perhaps explain the wide differences in the recorded results. Strenuous attempts have been made to arrive at more satisfactory results by other methods. Neumann, in particular, has pointed out new lines on which to attempt the ansesthetization of the membrana tympani and of the organs of the middle ear. Otologists are not in agreement as to the value of these methods : they, however, certainly point out a way by which we can bring about a very thorough deadening of sensibility of the interior of the middle ear. Neumann discovered that an anaesthetic injected into the upper wall of the auditory meatus in such a manner as to raise it from its bed finds its way between the two layers of the membrana tympani, and thus brin^-s about ansesthesia of the drum and of the middle ear (Fig. 12). A 2 2^er cent, novocain solution is employed with 3 minims of added suprarenin to each 5 c.c. of solution. The heating of the solution to 45° C, which Neumann recommends, is not necessary. The needle is inserted from ^ to 1 centimetre in front of the junction between the cartilaginous and the bony portions of the meatus. The line of junction can be recognized by a fold formed when the pinna is raised or lowered, also by the glisten- ing of the bony portion. The needle is passed 116 LOCAL ANESTHESIA upwards and inwards in a slanting direction, thus between the bone and the upper cutaneous wall of the meatus. The anaesthesia is fully established in about ten minutes. That of the drum is complete, that of the middle ear-organs, though not quite complete, is nearly so. For operations on the membrana tympani, Fig. 12. — Anesthetization of the Membrana Tympani and Middle Ear (Neumann). especially paracentesis, the method has not gained wide adoption, as there is a general agreement that the pain of the injection is no less severe than that of the paracentesis itself. On the other hand, the method, though per- haps not yet fully perfected, appears to point OPERATIONS ON THE HEAD 117 to the right way in which to bring about ana-^s- thesia for operative procedures on the middle ear, which often require considerable time to carry out. Where the tympanic cavity is to be attacked by way of the auditory meatus the method is as a rule sufficient in itself. If a trephining of the mastoid process is to be combined with the " radical " operation, the method must be reinforced by the simple and sure method of anaesthetization of the bone from without. The mode of procedure follows from what has been said above. It is only necessary to sur- round the mastoid process with a deej), and a superficial infiltration with 1 j)er cent, novocain- suprarenin solution, and the bone can be tre- phined painlessly in from ten to fifteen minutes. The deep infiltration should be, as far as possible, subperiosteal. The above- described method of anaesthetizing by way of the meatus then comes into use for the deeper parts. The performance of this operation under Schleich's anaesthesia alone — that is, after a gradually progressive infiltration carried deep into the bone, as has been practised by some surgeons — has, in my opinion, this serious drawback — viz,, that in a region so rich in lymph channels infectious material may very readily be carried l)y the infiltration to the deeper parts. 118 LOCAL ANESTHESIA In operations on the peripheral portions of the nose we can either employ a circular infiltration, for which, owing to the tenseness of the tissues, only small quantities of solution are required, with little or no added suprarenin. For the removal of small tumours this is the most prac- tical method. For plastic operations, where the area of operation is to be treated as gently as possible, conduction anaesthesia is to be preferred. It must be borne in mind that the nasal branch of the ethnoidal nerve issues at the junction between the bony cartilaginous portions of the nose, also that the alae nasi and the septum receive sensory twigs from the upper lip. In order to anaesthetize the whole lower end of the nose, its lower border must be infiltrated first deeply, then subcutaneously, the upper lip being elevated for the latter infiltration ; afterwards, starting from the ridge of the nose, injections are made outwards and downwards, in a slanting direction, until the former injection points are met with. The deeper parts also (cartilage) are thus rendered anaesthetic. If it is desired to anaesthetize the whole organ, the second infil- tration must be carried out from the root of the nose along its lateral borders, and it will be necessary, in view of the nasal branch of the ethnoidal nerve, to inject specially a narrow strip at the junction of bone and cartilage (Braun). OPERATIONS ON THE HEAD 119 Operations ox the Nasal and Buccal Cavities. I have already stated that for producing anaes- thesia of mucous membranes cocahi has not yet been altogether ousted by other anaesthetics. In two respects, indeed, its replacement by other substances is not so urgently called for here as in the method of anaesthesia by infiltration. In the first place, the question of sterilization is here of subordinate importance, while, in the second, it is less necessary here to insist on entire freedom from tissue-irritant qualities in the drug employed than is the case with subcutaneous injections. There remains, however, the risk of poisoning, which, in sj)ite of improvement since the intro- duction of suprarenin, is, in my opinion, a some- what serious one, though cases of severe poisoning are but rare. Those who still, at the present day, employ cocain for anaesthetizing mucous membrane, give as their reason that for this particular purpose none of the newer preparations equal cocain in respect of the completeness of the anaesthesia produced. A number of other authors, however, state, in opposition to this view, that here also they have had excellent results with the newer anaesthetics, particularly with novocain and alypin. Both of these are used, like cocain, in 10 to 20 120 LOCAL ANESTHESIA per cent, solution. The dose of suprarenin must be fairly strong, about 5 minims per cubic centimetre. "^^ The application is made with a brush (pharynx), or by placing in situ pledgets of cotton-wool soaked in the solution and changing them frequently. Care must be taken that none of the solution passes down the oesophagus, and to this end too free a soaking of the cotton-wool should be avoided. The shrinkage of mucous membrane caused by the action of suprarenin is in many cases of great importance as an aid both to diagnosis and to the carrying out of operative procedures. The anaesthesia brought about in this manner is limited to the mucous membrane. If operations on bone are to be undertaken (septum resections, etc.), infiltration must take the place of external applications. In septum resections the surgeon injects on both sides of the septum beneath its covering mucous membrane with 1 per cent, novocain solution with a small addition of supra- renin, and proceeds gradually from before back- wards. Attempts have quite recently been made {Rujjpreclit) to devise a satisfactory local anaes- thetic technique for two minor operations of great * Haike has several times observed, after the use of supra- renal preparations, a nasal discharge, very troublesome to the patient, and lasting several days. OPERATIONS ON THE HEAD 121 importance to the practical surgeon — for the extirpation of tonsils and the removal of adenoid vegetations. Many surgeons deny the necessity of any local anaesthesia for these two operations, and object, on account of the expenditure of time, to a prepa- ration for operation whose duration seems out of all proportion to the short time necessary for the actual operative procedure. At the same time, the efforts being made in the matter deserve attention. If the public should come to realize that it is pos- sible to perform these operations painlessly, under local anaesthesia, many patients will certainly express a wish that it shall be done in their case. At present, however, the methods are by no means perfected, for " painful "or '' slightly painful " are words still frequently occurring in reports of cases. Many patients, too, and especially young children, are unsuitable subjects for any method of the kind. In the operation for the removal of adenoid vegetations it is of the first importance to anaes- thetize thoroughly the very sensitive appendage to the choana. In particularly sensitive patients, with a view to rendering the mirror examination also painless, about 1 c.c. of cocain-suprarenin solution should be first cautiously applied to the interior of the nose as a spray. After waiting from eight to fifteen minutes from the onset of anarjsthesia pledgets of cotton -wool soaked in 122 LOCAL ANESTHESIA 10 per cent, alypin-suprarenin solution are intro- duced by means of sounds or applicators into the nostrils, while the patient lies down with head thrown back. A sound is left for a time in each nostril with its pledget in contact with the appendage to the choana. After a few minutes the sounds are changed for fresh ones, the process being repeated three or four times, so that the whole procedure lasts about ten or twelve minutes. The surgeon waits a few minutes, and then carries out his operative procedures within the ensuing ten minutes. In operations on the tonsils the method applied is particularly suitable for the recently practised total enucleation of those organs. It consists in injecting (with a Record syringe, carrying a special attachment) 2 per cent, novocain solution into the tonsils, after Schleich's method. Before the injec- tion the tonsils may be painted with 10 per cent, alypin solution. The solution is injected into the tonsil around, and as near as possible to, its base. Sj3ecial importance is to be attached to the due infiltration of the upper pole of the tonsil (exit of nerve) ; the infiltration of the lower pole also is advisable, with a view to the prevention of haemorrhage. After the infiltration it is necessary to wait eight or ten minutes. In operations on the lachrymal sac it is OPEEATIONS ON THE HEAD 123 advisable to inject around the whole area of operation ; it is generally sufficient, in addition, to inject at the inner canthus (N. intratroch- learis) ; this cannot, however, always be fully relied on, as sensory branches often reach this region from a mesial direction. Operations on the Eye.* While, as we have seen, the ansesthetization of mucous membranes by external application pre- sents certain difficulties, the ocular conjunctiva is an exceedingly favourable field for the employ- ment of local anaesthesia. Apart from the pro- perty possessed by the conjunctiva of readily taking up watery fluids by diffusion, we can secure here a more prolonged action of the drug than we can with mucous membranes, by the simple plan of holding the lower lid a little away from the eye and making the patient look down- wards, so that the eye is bathed in the solution, filling the lower conjunctival sac. As a con- sequence we can secure satisfactory results with far less concentrated solutions of the anaesthetic drug ; this is desirable also, because too concen- trated solutions might easily be harmful to the corneal epithelium. The majority of ophthalmolo- ■■'- My thanks are due to Dr. Fehr for assistance in the preparation of this section. 124 LOCAL ANESTHESIA gists have remained faithful to cocain, though recently a number have also employed holocain, alypin, tropacocain, and novocain. For subcu- taneous and subconjunctival injection tropacocain must be entirely rejected, on account of its power- fully irritant effects ; novocain takes first place, and the otherwise almost abandoned eucain also renders good service. Alypin, in contrast to cocain, causes vaso-dila- tation, and in many cases gives rise to a condition of general irritability which is unpleasant to the patient. With reference to one important question, that of injury to the corneal epithelium, there is, at present, no general agreement of authorities. Many regard alyjDin as in this respect the most satisfactory anaesthetic ; others, on the contrary, maintain that with the usual precautions (covering the eye), and in solutions of the usual strength, cocain is the least harmful drug. The principal ground on which cocain has been, in other direc- tions abandoned — its toxicity — hardly comes into consideration here, on account of the small quanti- ties employed. The one drawback of cocain is its pupil-contracting, or myotic action. Where this would interfere with the operation, as in many iridectomies, those ophthalmic surgeons who generally employ cocain have recourse to some other drug. OPERATIONS ON THE HEAD 125 Local ansesthesia is of special importance in operations on the eye, not only because general anaesthesia must in these cases be very deep owing to the late abolition of the palpebral reflex, but also because it is often desirable during the opera- tion to let the i^atient carry out certain ocular movements. Vomiting, too, during or after the anaesthesia, imperils asepsis, and, in the case of incised operation wounds, involves danger of opening of the wound with all its consequences (prolapse of iris and vitreous). Even if general asaesthesia has to be resorted to, local anaesthesia is called in as an auxiliary. Fortunately, too, in the great majority of cases, a thoroughly satis- factory anaesthesia can be attained. For removal of foreign bodies from the cornea 2 per cent, cocain solution is employed, by instilla- tion into the conjunctival sac. From two to six drops are required. The same concentration and dosage are employed for the extirpation of chalazia, for the painful instillation of medicaments, for cauterization of the cornea, and for other opera- tions on the cornea and conjunctiva. The use of salves and oily solutions before operations is to be avoided, as they may smear over the site of opera- tion. The anaesthesia generally comes on very quickly. The addition of suprarenin is not necessary. Antiesthetization of the iris is usually effected 126 LOCAL ANESTHESIA by subconjunctival instillation, and requires free use of solution and prolonged application. Two to 5 per cent, solutions are employed, and the sur- geon must be prepared to find the anaesthesia in- complete, and to meet with evidences of slight pain when the iris is interfered with. It has been suggested that the anaesthesia should be made more complete by circular subconjunctival in- jection. Most operators, however, refrain from this, as the resulting chemosis complicates the operation. The plan recommended by Haab, too, of introducing crystals of cocain into the anterior chamber, should only be employed in exceptional cases. Where a sujBficient degree of anaesthesia cannot be attained, as in cases of marked ocular hyper- aemia, general anaesthesia must be resorted to. Many ophthalmologists employ in all intra-ocular operations a combination of cocain and suprarenin, others, however, only in hyperaemic conditions, or when, owing to alterations in the blood-vessels, haemorrhages are to be feared. The best propor- tion is 5 minims of suprarenin to each 5 c.c. of cocain solution. For puncture of the sclerotic, suture of wounds of the bulb, and magnet operations, instillation into the conjunctival sac is generally sufficient. Many also perform strabismus operations under simple instillation anaesthesia. Two minims of a OPERATIONS ON THE HEAD 127 2 to 5 per cent, solution of cocain are instilled. The subconjunctival injection of a 2 per cent, cocain- suprarenin solution at the point where the tendon is to be divided is very serviceable in, these cases. Even for the most severe of all ophthalmic operations, enucleation of the bulb, local anaes- thesia is, in many cases, sufficient, and this is particularly fortunate, as enucleation is often necessitated by morbid conditions of the eye, depending on disease of the blood-vessels, which render it desirable to avoid general anaesthesia. Some [Bostely) have performed enucleations pain- lessly under instillation anaesthesia. In cases of suppurating panophthalmitis, in which it is im- possible to secure anaesthesia by injections, and in which general anaesthesia is to be avoided, one must be content with instillation, though by this method it is impossible to attain complete anaes- thesia with any approach to certainty. Many and varied trials have been made of Schleich's method in enucleation operations. It has, however, been made plain by them that his dilute solutions do not suffice to produce complete anaesthesia. With the novocain-suprarenin solution employed to-day the anaesthetization j^resents, as a rule, no difficulties. After instillation of a few drops into the conjunctival sac about \ c.c. is injected sub- 128 LOCAL ANESTHESIA conjunctivally above, below, and at each side as far as the equator of the bulb, a fold of conjunctiva being pinched up each time for the purpose. From ^ to 1 c.c. is then injected into the orbit, the can- nula being passed into the bulb as far as possible in a nasal direction. Many operators use 2 per cent, eucain solution, others again employ 2 per cent, novocain or alypin solutions with suprarenin. Anaesthesia of the lips is very easily produced. In place of a circular we have here of course a semicircular or wedge-shaped line of injection points, the lip forming the base of the triangle. If anaesthesia of the whole lip is required, deep (submucous) injections must follow the subcuta- neous ones. Even when the area of operation extends upwards from the upper lip, or downwards from the lower, even to the lower border of the inferior maxilla, a semicircular or wedge-shaped injection will be found quite sufficient. If, how- ever, no deep injection is carried out, special attention must be given to the points of exit of the nerves mentioned above. A 1 per cent, novocain solution answers every purpose. With reference to operations on the upper and lower maxillae, as well as on the teeth, a few preliminary remarks must be made : OPEKATIONS ON THE HEAD 129 The infraorbital nerve (Fig. 13), the most important nerve supplying the upper jaw, passes from the pterygo- palatine fossa in a bony canal, from which it emerges through the infraorbital foramen. This last occupies a fairly constant position a little more than half a centimetre below the orbital border. The infraorbital nerve gives off: 1. Before its entrance into the bony canal and after its exit therefrom : Branches for mucous membrane, periosteum, and the anterior wall of the upper jaw. 2. Before it enters the canal : Branches which enter the bone at the tuber maxillae behind the appendage to the zygomatic process of the upper jaw (this can easily be felt from the mouth), and the last two of which often supply the first molars. These branches are often joined by others, which are given off directly from the main stem of the second ramus of the trigeminus. 3. In the bony canal : Branches for all the teeth of the upper jaw, including the first molars. The branches enumerated under the foregoing three heads constitute together the superior dental plexus which gives the rami alveolares, anterior, median and posterior. The branches mentioned in Sections 2 and 3 are generally connected with each other by an anastomosis (Moral). 130 LOCAL ANESTHESIA Further, of importance to us as supplying the periosteum and the gums on their lingual side are (Fig. 13) : 1. The N. palatinus ant., which issues from the bone by the greater palatine foramen at the level of the third molar. 2. The iV^. nasopalatimis^ which leaves the bone by way of the foramen incisivum. Fig. 13. — Neeves Supplying the Upper Jaw. These nerves are connected by an anastomosis (Bmite). Of great importance in regard to local ansesthesia is the fact that the nerve fibres which pass to the dental roots from the dental plexus lie close against the anterior and lateral OPERATIONS ON THE HEAD 131 wall of the upper maxilla, which is here exceed- ingly thin. As regards ansesthetization of the superior maxilla, we have seen that for small foci on the anterior surface circular anaesthesia by deep injec- tions is quite sufficient. If the focus is situated close to or above the point of exit of the supra- orbital nerve, it is advisable to infiltrate this point with especial thoroughness. Attempts to anaesthe- tize the whole upper maxilla by injections into the pterygo-palatine fossa {Matas) have led to no practically useful results, and, in view of the fact stated above, that the second ramus of the trigeminus often shares directly in the inner- vation, they can hardly be regarded as very promising. Local anaesthesia is of very great practical importance in regard to dental surgery, especially for extractions. It is true that in many cases, especially when the tooth is quite loose, the extraction may be rendered painless, or, at any rate, less painful by ethyl chloride. The method, however, is very imperfect, and is steadily giving place to more recent ones. As need hardly be said, it is necessary, when ethyl chloride is employed, to operate very quickly, and the pain following the operation is often very severe. Ethyl chloride is useful, however, for the incision of small periosteal abscesses. 132 LOCAL ANESTHESIA which are completely frozen and then quickly incised. For the great majority of dental operations con- duction anaesthesia is the most suitable method. We have seen that betv/een the terminal stem of the N. dentalis and the periosteum covering the anterior bony surface of the upper maxilla there lies a very thin bony lamella. That an anaesthetic solution, injected submucously or subperiosteally, can be forced directly through the bone into the neighbourhood of the nerve is, I think, placed beyond doubt by experience with Bier's method of " venous " anaesthesia. Thus Schleich's procedure has been to infiltrate (to the point of oedema) with his dilute (O'l per cent.) cocain solution the gum and periosteum in the neighbourhood of the dental alveolus, carrying the infiltration to a level above the entry of the nerve into the tooth, and then to use the ethyl chloride spray as an auxiliary. This method is now generally abandoned in dental practice, for experience has shown that it is not necessary to bring pressure to one's aid in order to ensure that the solution shall pass through the bone and reach the nerve, but that it is, on the contrary, sufficient to inject a " deposit " of a con- centrated solution just over the bone, the solution then reaching the nerve by diffusion. It is true that we always inject under pressure on the lingual side, where the mucous membrane is pretty OPERATIONS ON THE HEAD 133 closely attached to the periosteum. Even here, however, it is not to be assumed that pressure plays any important part in bringing about the anaesthesia, for, in the first place, only a small quantity of solution is injected, and, in the second, diffusion through the bone is not here in question, as our object is to afiect merely the branches of the palatine nerves running between the mucous membrane and the periosteum. These nerves, however, have nothing to do with the innervation of the dental pulp. Experience has fully proved the applicability in this connection of anaesthesia by interruption of conduction. It is only necessary to employ concentrated solutions and fairly large additions of suprarenin. Drug absorption, how- ever, appears to take place in very marked degree in the neighbourhood of the teeth, and with the use of cocain and suprarenin, symptoms of poison- ing, fortunately, as a rule, of a quite transitory character, have been observed in a large number of cases. Since the introduction of novocain such toxic symptoms have, according to many observers, ceased to appear. For dental extractions to-day 2 per cent, novo- cain solution + 1 minim of suprarenin to each cubic centimetre is generally employed. For difficult extractions a slightly larger dose of suprarenin is taken (3 to 4 minims per 2 c.c). For operations on dentine, resection of fangs, and other operations 134 LOCAL ANESTHESIA hardly coming within our purview, a 1 per cent, novocain -suprarenin solution is generally em- ployed. According to the great majority of observers this mixture of novocain and suprarenin causes no injury to the tissues. As, however, extraction of teeth is always accompanied by more or less damage to tissues, sometimes even by oedema, it is not yet possible to speak decidedly on the point. A still larger volume of experience will be necessary before we can decide whether the free dosage of suprarenin here requisite is, in reality, quite harmless to the tissues. In order to make the injection itself painless to very sensitive patients, a pledget of cotton- wool soaked in 20 per cent, novocain solution may be kept applied to the mucous membrane for ten to fifteen minutes jDreviously. In order to render painless the extraction of an upper tooth, we elevate the lip and inject 0'5 to 1*5 c.c. of 2 per cent, novocain-suprarenin solution on the labial side of the tooth, passing the needle horizontally deep into the space between mucous membrane and periosteum over the affected tooth, at the level of the fold where the labial or buccal mucous membrane passes over to that of the gums. For the two last molars, however, whose nerves course over the bone above the tuber maxillae, we inject the solution behind the easily felt zygomatic process in a more vertical direction. OPEEATIONS ON THE HEAD 135 We always inject from within outwards, so that the solution leaves the needle at a point above, and somewhat lateral to, the tooth to be anaesthetized. For injection on the lingual side but little solution is required, 0'25 to 0*5 c.c, so that for the extrac- tion of one or two teeth hardly more than 0'2 c.c. of solution is required in all. The solution is in- jected deeply into the gum on the lingual side of the tooth. Fairly strong pressure is needed, as the mucous membrane and periosteum are closely connected. Infiltration of the point of exit of the palatine nerves is only necessary where a number of teeth are to be extracted. If it is desired to "catch" the N. palati?iits anterior at a central point, it will be necessary to inject also at the fora- men incisivum of the N, nasopalatinus, as the two nerves are connected by a loop. The point of exit of the N. palatmus anterior lies opposite the last molar tooth, and about 1 centimetre mesial to it, that of the N. nasopalatinus in the middle line, J to 1 centimetre behind the central incisor teeth. The period of waiting required is about five minutes. After ten minutes one may be sure that the effect will be fully developed if the injection has succeeded at all. For operations on the hard palate it is sufficient to bear in mind the above-mentioned points of exit. A 1 per cent, solution generally suffices, as also for operations on the soft palate, which is either 136 LOCAL ANESTHESIA infiltrated diffusely or cut off from its sensory- nerves by a semicircular injection along the border between soft and hard palates. There remains to be considered the method of producing anaesthesia for the operation of opening the antrum of Highmore. This can almost always be successfully performed under local anaesthesia. If the antrum is to be opened through an alveolus the procedure is exactly the same as for an extraction, except that the anterior surface should be somewhat more freely injected. Tre- phining the antrum, by way of the anterior surface of the maxilla, is also free from difficulty as regards local anaesthesia. Free submucous infiltration is made, with 1 per cent, novocain-suprarenin solution, of the whole of the anterior surface in the neighbour- hood of the selected site of operation. In addition, the needle is passed as high as possible in order to leave a few cubic centimetres of solution about the point of exit of the infra- orbital nerve. After waiting five minutes the trephining can then be carried out quite painlessly. By this latter method the mucous membrane is anaesthetized over the greater portion of the facial wall of the antrum. If, however, the mesial wall here is to be interfered with, the mucous membrane must, after the opening has OPEEATIONS ON THE HEAD 137 been made, be painted with 20 per cent, novocain solution. For the opening of Highmore's antrum from the lower nasal passage, injection into the muco- periosteal covering of that region is sufficient. If the opening is to be made from the border of the pyriform aperture, deep injections from the mouth, pushed to the extent of elevation of the perios- teum, will produce a sufficient ansesthesia ; the cutting of the bone is, however, generally found hard to bear owing to the vibration caused by the trephine. The nerve suj)ply of the lower maxilla is as follows (Fig. 14) : 1. The N. alveolar is inferior supplies the peri- osteum and pulp of all the teeth, as also the gums and alveolar periosteum on their labial side. 2. The N. lingualis supplies the lingual side of gums and alveolar periosteum. The N. alveolaris inferioi^ enters the lower jaw- bone on its medial side at the so-called lingula. Before it enters the bone it runs for a space along the inner surface of the latter about 1-^ centi- metres behind the N. lingualis. During its course within the bone the N. alveolaris inf. gives off branches for the dental roots {Plexus dentalis vnferior) and the gums. One branch, the N. mentalisy emerges from the bone about opposite 138 LOCAL ANESTHESIA the first bicuspid — the point of exit is not very constant — and takes part in the innervation of the labial gums. In the middle line there are numerous anastomoses between the nerves. As regards the ansesthetization of the teeth of the lower jaw, the general principles laid down above in connection with the upper jaw apply here mutatis mutandis. Ill L N. lingualis N. alveo- laris inf. Fig. 14. — Nerves of the Lower Jaw. Many dentists employ for all the lower teeth, at any rate for all single extractions, the method of sub-gingival injection above described. The majority, however, while adopting this method for the mesial teeth, including the canines or even the first bicuspids, employ the method of anaesthesia by interruption of conduction in the N. alveolaris inf. for the lateral teeth. Others, again, combine both methods. Interruption of conduction in the inferior OPERATIONS ON THE HEAD 139 alveolar nerve, and in the lingual nerve, after Halsted's method, is not an easy matter for the beginner in local anaesthesia, and gives good results only to those of wider experience. The technique has been elaborated chiefly by Hiibner and Braun : the mouth being open, the sharp anterior border of the coronoid process of the lower jaw is felt behind, and slightly lateral to, the third molar tooth, a little internal to this again is another bony ridge, the linea ohliqua {interna). Close to this, and about one centi- metre above the masticatory surface of the molars, lies the lingual nerve immediately beneath the mucous membrane. Passing now backwards in a direction parallel to the upper surface of the molar teeth, and keeping close to the bone, one comes upon the inferior alveolar nerve about l\ centimetres behind the lingual, and just before its entry into the bone. The solution generally used for injection here is a 2 per cent, novocain solution + 1 to 2 minims of suprarenin per cubic centimetre. The index finger is passed into the mouth over the last molar tooth, until the extremity of the nail, the surface of which looks towards the middle line, meets the linea obliqua. The needle is then inserted about 1 centimetre above the last molar (not too far in a mesial direction) until the bone is felt ; it is then withdrawn slightly, and about 140 LOCAL ANAESTHESIA •25 c.c. injected for the A^. lingualis. For the N. alveolar is inf. the needle is pushed on backwards for a distance of 1^ centimetres, always keeping close to the bone and maintaining a direction parallel to the molar masticating surface. Dur- ing the passage of the needle the remainder of the solution is injected, thus about 1 c.c. in all. (Fig. 15.) After about 5 minutes anaesthesia comes on in the region supplied by the lingual nerve. For the inferior alveolar nerve it is necessary to wait 20 minutes or, to be safer, half an hour. Failures Fig. 15. — Anesthetization of THE Inferior Alveolar are by no means un- Nerve (Braun) ^^^^^ ^^^^ ^^ practised a. Bony ndge. ^ ^ operators. With a view to their avoidance, Blinte has recommended that, in view of an anastomosis which is frequently present, some solution shall be injected at the point of exit of the N. mentalis (below the first or second bicuspid). It may be further pointed out that the point of entry of the N. aheolaris inferior into the bone is at a lower level in chil- dren and the aged than in young adults. In carrying out the sub-gingival method of OPERATIONS ON THE HEAD 141 anaesthetizing the teeth of the lower jaw, it should be remembered that the bone is thicker and denser on its labial side than that of the upper jaw, therefore the dose of solution injected must not be too small. The technique of injection is the same as already described for the upper teeth, except that on the lingual side the injection must be made at the fold, where the mucous membrane of the gums joins that of the floor of the mouth. It is also important that the solution should be injected a little behind the affected tooth. The method is not quite certain for the lower molars, though the results are often perfectly satisfactory. As regards other operations in the region of the lower jaw» the most important, from a practical point of view, is the incision of a parulis. Here, where we have to do generally with large inflammatory swellings closely connected with the deeper tissues, circular anaesthesia is not generally found to give the results desired. If, as is most frequently the case, we have merely to open an abscess, Schleich's infiltration method is the most suitable. As has been stated, it is generally possible to infiltrate painlessly the stretched, and only secondarily involved, skin. No wheal is formed, but merely a diffuse oedema. If the infiltration is carried step by step into the deeper tissues, the abscess can generally be 142 LOCAL ANESTHESIA incised painlessly, and the wound then somewhat enlarged. If it is necessary to deal with the bone itself, which in these abscesses is seldom the case, it is safer to anaesthetize the inferior alveolar nerve by the method we have described, and, in addition, to inject the whole area of operation. As a rule, however, general anaesthesia is to be preferred in these cases, especially as a certain amount of immobility of the jaw often prevents injection of the nerve. For operations on quite superficial morbid foci affecting the lower maxilla, the method of circular analgesia with a special injection at the point of exit of the iV. mentalis will be found to answer every purpose. It is easy also to produce a satisfactory anaesthesia for operations on the middle ne, as, for instance, suture of a broken maxilla. A fairly long needle is inserted at the chin and . a free infiltration, subcutaneous, submucous, and, so far as possible, subperiosteal, is carried out, both before and behind the bone, with 1 per cent, novocain solution. A finger inserted into the mouth feels and controls the needle through the labial or lingual mucous membrane. One needle puncture is generally sufficient in view of the free movability of the skin. If a tooth has to be extracted, the neighbourhood of its alveolus must be specially freely infiltrated ; free sub- OPERATIONS ON THE HEAD 143 cutaneous infiltration is then carried out on either side of the line of incision, the lips being of course also infiltrated if necessary. It is not necessary to infiltrate specially about the mental foramen. If the area of operation is more laterally situated conduction is first interrupted in the inferior alveolar and lingual nerves in the manner already described, the soft parts involved being then anaesthetized by circular infiltration. In suture of the horizontal ramus of the lower maxilla this interruption of conduction is, according to Braun, not necessary. From points about 2 centimetres on either side of the point of fracture he infil- trates the anterior and posterior surfaces of the bone, and also the subcutaneous and submucous cellular tissues, as described above for operations on the middle line. After exposure of the frac- tured ends he injects a little concentrated solution into the lateral opening of the bony canal for the nerve. Of other operations about the lower jaw mention need only be made of extirpation of glands from the submaxillary region, which, unless the glands are adherent to the subjacent tissues, can be carried out quite painlessly under circular analgesia (using preferably 1 per cent, novocain solution). The same applies to operations on the cheek and the floor of the mouth. As regards operations on the tongue — it is 144 LOCAL ANESTHESIA only for the anterior half of the organ that local anaesthesia comes into question at all — the method of circular analgesia is quite effective. Braun first anaesthetizes the tip of the tongue by submucous infiltration, and passes a strong retaining thread through it. It is not possible to produce with certainty anaesthesia of any part of the tongue by interruption of conduction in the larger nerve trunks. No attempt should be made to operate on large carcinomata of the tongue under local anaesthesia, as in these cases the glands are almost always involved, and a complete and radical removal is necessary. CHAPTER IX OPERATIONS ON THE CERVICAL REGION Although the internal organs of the cervical region are in chief part supplied by three nerves {auricularis magnus, cutaneus colli, and supra- clavicularis), which are fairly easily reached at the point where they emerge at the posterior border of the sternocleido-mastoid, the ansesthetization of these nerve-trunks has not, in consequence, ap- parently, of the numerous anastomoses between these and other nerves in the neighbourhood, established itself as a practical method. For the most important operations in this region, extirpa- tion of cervical glands and strumectomies, the method of circular analgesia is exclusively em- ployed. In the extirpation of cervical glands, however, local anaesthesia is but of limited appHcation, and must not be employed save where the glands are fairly superficial, and are easily separable from their surroundings. For the removal of small glands a free infiltration is made of 1 per cent, novocain solution, a 0*5 per cent, solution 145 10 146 LOCAL ANESTHESIA being employed if the area of operation is more extensive. In those cases, however, where a long chain of larger and smaller glands extends into the deeper tissues along the large bloodvessels general anaesthesia must be resorted to in pre- ference ; otherwise one will frequently be placed in the embarrassing position of having to continue under general an operation begun under local anaesthesia. For the simple incision of lympha- denitic abscesses the rules above laid down with reference to parulis hold good. The matter is more complicated, however, if it is desired to scrape out an abscess cavity which extends deeply and is adherent to the subjacent parts, so that it is impossible to inject all round it. In such a case we must adopt Schleich's method, and, as the incision is deepened, infiltrate step by step the deeper layers, always proceeding from the healthy towards the diseased tissues. This rule should be strictly adhered to. On the other hand, in removing an aseptic cystic tumour which is connected with the deeper tissues, so that the method of primary circular anaesthesia is imprac- ticable, the deeper layers may be infiltrated directly from the operation wound. At the same time the beginner, at any rate, should realize that in all these conditions it is inadvisable to form too wide a conception of the indications for local anaes- thesia. OPEEATIONS ON THE CEKVICAL REGION 147 Local anaesthesia has very rapidly advanced in the favour of surgeons for the removal of a bronchocele. Formerly the greater part of the operation could be carried out painlessly ; as soon, however, as it came to the actual dislocation of the thyroid gland, the methods then in use failed as a rule. As methods have been perfected it has become possible to secure that this part of the operation also shall be performed painlessly in the majority of cases. There is still a good deal of difference of opinion with regard to the ^Droportion of cases in which local anoesthesia is indicated. Many operators always remove the thyroid gland, even in cases of retrosternal extension, under local anaesthesia ; it must be admitted, however, that in the more difficult cases of thyroid excision the anaesthesia is by no means completely to be relied on, especially during the luxation of the gland. The solution generally employed is a 0*5 per cent, novocain - suprarenin solution. As regards the dosage of suprarenin, marked differences of opinion prevail. Bier, for instance, adds 1 minim and Hackenbruch 4 minims (both non-synthetic supra- renin) to each 10 c.c. of solution. I have found the addition of 1 to 2 minims of synthetic supra- renin per 10 c.c. answer every purpose. In small bronchoceles, for which not more than 50 or GO c.c. of solution are required, it is, in my opinion, quite suitable to employ a 1 per cent. 148 LOCAL ANAESTHESIA novocain solution. Of the O'o per cent, solution we may inject without misgiving 100 c.c. or more. Some surgeons use alypin (0'5 to 1 per cent, solu- tion) + suprarenin, and also report good results. The technique of circular injection in these cases is very simple. It is best to inject at four points (which may be first rendered anaesthetic by the cutaneous wheal method), first at the border of the sterno-mastoid deep into the connective tissue surrounding the bronchocele, in the direction fol- lowed by the great bloodvessels, and then above and below as deeply as possible beneath the fascia. A complete surrounding injection of the deeper tissues is often impossible ; it is, however, suf- ficient to pass the needle as far as possible under the tumour. The injection of the deeper tissues must follow^ the circular subcutaneous injection. Finally, the neighbourhood of the isthmus is injected. To guard against injecting into a vein the needle should be withdrawn after making the puncture, so as to satisfy oneself that no blood issues. As an additional precaution, the needle may be kept constantly moving during the injec- tion. After the injection is completed, sufficient time (at least ten to fifteen minutes) must be allowed for anaesthesia to develop. The anaesthesia will last long enough unless the operator is abnor- mally slow. Morphine is administered beforehand to excitable patients by many surgeons, Hacken- OPERATIONS ON THP] CERVICAL REGION 149 bruch gives two closes of tincture of opium, the first an hour and the second half an hour before the operation, and maintains that, in this way, the vomiting often observed during the operation when morphine has been injected is avoided. In my opinion, however, better results are obtained without the use of narcotics. Among other operations on the cervical region tracheotomy can be performed satisfactorily under circular anaesthesia. The needle is inserted on either side, a centimetre or two from the middle of the line of incision, and a 0*5 or 1 per cent, novocain + suprarenin solution is infiltrated into the surrounding tissues, with special thoroughness into the deeper tissues at the sides of the trachea and around the lower part of the larynx, finishing with a subcutaneous infiltration. For the ansesthetization of the laryngeal mucous membrane it is generally sufiicient to apply a 20 per cent, novocain solution to which 3 minims of suprarenin per cubic centimetre have been added. About 3 c.c. of this solution in all are employed, in separate applications, at intervals of three to four minutes. Alypin in 20 to 25 per cent, solution is also employed in these cases by a number of surgeons ; others, again, hold to cocain, maintaining that it is the most reliable anaesthetic for this mucous membrane. As, however, 20 per cent, solutions are generally necessary, the need 150 LOCAL ANESTHESIA N. laryng. sup. for some method other than that of external apph cation to the membrane has been strongly felt. Frey has anaesthetized the laryngeal mucous membrane by interruption of conduction in the nerve which supplies it, the superior laryngeal. This nerve supplies the mucous mem- brane, from the epi- glottis to the vocal cords, with sensory fibres. Below, the glottis fibres of the inferior laryngeal nerve also take part in the innervation, so geuS" tl^at here the anaes- thesia is no longer re- liable. The superior laryngeal nerve passes through the hyothyroid mem- brane into the larynx, and can be reached at the point at which this pas- sage takes place (Fig. 16). About 1 c.c. of a 2 per cent, novocain-suprarenin solution is in- jected on either side, the operator selecting a point midway between the greater cornu of the hyoid bone and the upper border of the thyroid cartilage, and, in strong adults, about 3 centi- FiG. 16. — Nerves of the Larynx. OPERATIONS ON THE CERVICAL REGION 151 metres from the middle line. The needle is passed horizontally and slightly towards the middle line. The patient is told not to swallow during the injection, as this causes a change in the relative positions of the parts. The solution is ejected at the point where the nerve enters the membrane— some surgeons pass the needle through the membrane and then inject. The anaesthesia reaches its height in from ten to fifteen minutes, and lasts in usable degree for about twenty minutes. It may, however, last much longer, even in some cases from one to two hours. It is, of course, necessary to add to the injection a local application to the fauces in order to cut off the faucial reflex. Hecently {Biei') many major operations on the larynx — in particular, extirpation — have been carried out under local anaesthesia. For this, interruption of conduction in the superior laryn- geal is not sufficient. It is necessary, in addition, to inject around the whole larynx with 0*5 per cent, novocain-suprarenin solution. Two cuta- neous wheals on either side of the larynx are generally sufficient, so far as the skin is concerned. The deeper parts on either side of the larynx and trachea are freely infiltrated, and a circular sub- cutaneous infiltration is added. If the technique for anaesthesia of the superior laryngeal is correctly carried out, the local application to the ixiucous. 152 LOCAL ANESTHESIA membrane, which formerly accompanied the cir- cular injection, will be found hardly necessary. Circular anaesthesia is quite reliable for the incision of boils or carbuncles at the back of the neck In view of the rich blood-supply in this region, the dose of suprarenin should not be too small. In very large carbuncles it is often not an easy matter to ensure complete painlessness if the latter is to include, as is, of course, to be desired, the injection itself As the inflammation here extends far into the deeper tissues, it is often necessary to inject subcutaneously into the healthy area all round the carbuncle (preferably with 1 per cent, solution), and then, after allowing a short time for the diflusion of the solution, to pro- ceed to infiltrate gradually the deeper parts. In order to ensure complete anaesthesia it is necessary to inject freely beneath the inflamed area, for, in the first place, fairly large sensory branches pass outwards through the fascia ; and, secondly, the pressure of the knife in making the incision causes a compression of the deeper parts which, if the anaesthesia be incomplete, gives rise to severe pain. CHAPTER X OPERATIONS ON THE THORAX Operations on innocent mammary tumours are particularly suitable for local anaesthesia. The ordinary surrounding injection, with, if the tumour is extensive, an infiltration of the retro-mammary tissue, is sufficient in all cases. For malignant tumours of the breast, on the other hand, local anaesthesia must be entirely dis- carded, since, even if the removal of the mamma itself were possible, the radical extirpation of the axillary glands could not be carried out painlessly under any local anaesthetic method. Operations for suppurative mastitis are quite feasible under local anaesthesia, especially if one confines oneself to small incisions and then employs Bier's suction apparatus. In circum- scribed suppurations one can, of course, inject all round the diseased focus. In the more severe cases, however, it is best to have recourse to Schleich's infiltration method. The stretched and only secondarily inflamed skin as a general rule admits, as is the case with gumboils, of the 153 154 LOCAL ANvESTHESIA injection being carried out painlessly. It is necessary here, however, to operate with great caution and to avoid interference with the deeper parts of the inflamed area. For manipulations of the latter kind, especially for dilatation of the abscess with the finger or with forceps, local anaesthesia is only effective if injections are made all round and beneath the area of operation. In puncture of the pleura, infiltration of the sub- cutaneous and deeper tissues will enable the small operation to be carried out quite painlessly. Of operations on the bony thorax, the one most commonly performed under local anaesthesia is the resection of ribs for the evacuation of an empyema. We have seen in a previous chapter that it is not always necessary to inject beneath the periosteum in order to render the bone anaesthetic by inter- ruption of conduction, but that it is often sufficient to inject freely into the deeper tissues adjoining the periosteum. Two points therefore are marked, one below and one above the middle of the chosen line of incision, and from these 1 per cent, novo- cain-suprarenin solution is injected all round the section of bone to be removed so that it is, so far as is practicable, bathed in the solution. We inject first at the lateral then at the mesial border beneath the rib, then in the deeper tissue-layers above it. It is advisable also to bathe the rib in anaesthetic solution at the middle of the line of OPERATIONS ON THE THORAX 155 incision ; so that we have here no pure conduction anaesthesia. The whole operation area is then subcutaneously injected. A dose of 50 to 60 c.c. of solution is usually sufficient. Should it not prove so the injection should be completed with 0'5 per cent, solution. If it is wished to proceed by Schleich's method the subcutaneous cellular tissue and musculature are first infiltrated, then the anterior and pos- terior borders of the rib, so far as possible sub- periosteally. The rib is then resected and the pleura infiltrated separately. What has been said with reference to the ribs applies also to their cartilages. I have, for instance, carried out entirely painlessly by this method a Frcund's operation (resection of the first to the fourth costal cartilages). The ansesthetiza- tion of the first rib presents some difficulty in these cases. It must be freely bathed in 1 per cent, solution. Here, in view of the near neigh- bourhood of large bloodvessels, special care must be taken to keep the syringe always in movement during the infiltration. Anaesthetization for operations on the clavicle is, on the contrary, a very simple matter, for which there is no necessity to add to the rules laid down in the foregoing. Carious foci in the ribs or sternum can also be operated on successfully under circular anaesthesia, 156 LOCAL ANESTHESIA provided that the extent of the diseased area, and so of the possible field of operation, is accurately known beforehand. It is then only necessary to be sure that the deeper tissues are sufficiently infiltrated. Even when the disease is found to extend farther than was expected it is often possible, with a stout needle, to infiltrate the bone marrow freely from the opening made into the medullary cavity, and so again attain an anaesthetic condition. CHAPTER XI OPERATIONS ON THE EXTREMITIES We are here in a region in which our knowledge is at the present time very largely in a state of flux. Bier's ' venous ' anaesthesia has won quite new prospects for local anaesthesia, and we may confidently expect that before long we shall succeed in changing the " encouraging results " and " failures," which are to-day reported, into complete successes. For major operations on the extremities, especially for amputations and re- sections, local anaesthesia has not as yet, in spite of isolated successes, become really popular ; in the lower extremity, spinal anaesthesia has offered a substitute. It is, however, worth endeavouring to supersede this method, which is by no means free from danger, by local anaesthesia, where it can be applied. Wherever possible we shall prefer our older methods to that of venous anaesthesia, if only for their greater convenience. Among operations on the shoulder and axillary region those on glandular abscesses offer the most frequent occasion for the employ- 157 158 LOCAL ANESTHESIA ment of local anaesthesia. What has been said above as regards the cervical region applies here also. Foci M^hich are adherent to the subjacent tissues are difficult to ansethetize, unless a super- ficial incision is all that is required. Only in the case of secondarily inflamed skin should one begin by infiltrating a diseased tissue. In other cases it is necessary, following Schleich's practice, to proceed gradually from the healthy to the diseased tissues. I have several times operated on subdeltoid bursse under local anaesthesia. As these are generally connected with the shoulder joint, or at any rate lie very close to it, it is as a rule only possible to infiltrate the deeper tissues after incision through the more superficial layers. Crile has performed an exarticulation of the shoulder by the aid of endoneural injection into the brachial plexus, which he exposed at the posterior border of the sternocleido-mastoid. He injected into each nerve enough solution to produce a slight bulging. The operation was painless, except as regards the skin incision. I mention the method, because, in exceptional cases, if general anaesthesia is contraindicated, it may be worth considering as a last resort. It should hardly be employed as a method of election. Most operations on the superficial tissues of the upper arm, elbow, and forearm can be performed OPERATIONS ON THE EXTREMITIES 159 under local anaesthesia. It is employed very frequently for operations on the olecranon bursa. As the posterior border of the bursa is firmly adherent to the bone, it is necessary to infiltrate the deeper tissues thoroughly in order to interrupt conduction in all nerves entering the periosteum. If it is desired to anaesthetize large areas of skin, e.g. for the removal of skin grafts {ThierscJis method), the following procedure advocated by Braun may be adopted : As the nerves of the upper arm, in part at any rate, only pass through the fascia immediately before their terminal ramification, a simple injec- tion around the area of operation is not, in the case, at least, of the more extensive areas, sufficient. The operator therefore marks on the outer aspect of the arm eight or ten injection points about 2j centimetres distant from each other, and from these infiltrates the subcutaneous cellular tissue backwards and forwards in slanting lines. The solution is then distributed by gentle massage movements. A 0*5 per cent, novocain solution with a small addition of suprarenin is the most suitable, and is to be preferred to the cooling by ether spray recommended by Braun. If more than 100 c.c. of solution are required, the further infiltration, if the operator hesitates to use more of this solution, should be made with one of '25 per cent, strength. 160 LOCAL ANESTHESIA Schleich's method of endermal infiltration appears quite unsuited for this operation, apart altogether from its complexity, as it is here especially necessary to avoid any treatment likely to injure the tissues. The anatomical distribution of the nerves above described is to be borne in mind also in the case of other operations, especially those on tumours of considerable size. Where the area of operation is extensive it is always necessary to inject beneath as well as around it. In the forearm, it is true, most of the nerves run subcutaneously for considerable distances ; the only exit of a larger nerve through the fascia being that of the superficial radial nerve. For the majority of operations, therefore, an oblique, circular, or semicircular injection will suffice. Variations in the course of the nerve are, however, sufficiently frequent to indicate the method of injecting beneath as well as around the operation area as the one to be generally employed. Of major operations, amputation of the forearm especially has been frequently performed under Schleich's infiltration anaesthesia. Each layer of tissues must here be separately infiltrated. In view of the large quantity of solution required, it is best to employ a '25 per cent, novocain solution. Nerve-trunks must be treated with special thoroughness. After division of all soft parts, a OPERATIONS ON THE EXTREMITIES 161 very free subperiosteal infiltration is necessary. Schleich has performed amputations of the fore- arm and leg under this method. In general, however, this method may, in such operations, be replaced by Bier's venous anaesthesia, which is applicable to operative procedures up to the junction between the lower and middle thirds of the upper arm. In practice it would find most frequent and suitable application in resections of the elbow and in operations on large osteomyelitic foci. Anaesthesia comes on sooner in the arm than in the leg, on account of the smaller calibre of the former. The indirect anaesthesia also generally comes on in a few minutes. Fifty c.c. of solution will always suffice. The anatomical relations of the veins and the method of finding them are described above (p. 89, Figs. 5-9). Direct anaesthesia is indicated for elbow resections and operations on the arm. For operations on the forearm Bier prefers the indirect anaesthesia on account of the difficulty sometimes observed in carrying out the injection owing to the presence of the valves in the veins. For successful anaesthetization of the fingers and hands, it is of the greatest importance in the first place to understand the course of the sensory nerves supplying the fingers. Id practice the chief point to bear in mind is that two pairs of nerves, a radial and an ulnar, 11 162 LOCAL ANAESTHESIA a dorsal and a volar nerve, run fairly close to the bone {vide Fig. 17). On this fact is founded the so-called Oberst's method of interruption of conduction in the nerve-trunks at the base of the fingers, which, with Coming's experiments, con- stitutes the foundation for the whole theory and method of anaesthesia by interruption of con- duction. Oberst used an elastic ring, slipped over the finger as a tourniquet. Later, a thin rubber band was w^ound round the base of the Fig. 17. — Course of Nerves supplying the Fingers. finger, the ends being crossed over the back of the hand, carried round the wrist, and either tied in a knot or held together by forceps. The use of suprarenin preparations in operations on the fingers has rendered these methods of cutting ofi'the blood-stream more or less unneces- sary. It is, however, advisable, especially in operations on the base of the fingers or at a still more central point, to slow down the blood -stream considerably. In such operations, therefore, we apply (not tightly, so that little or no pain is caused) a rubber band round the lower third of OPERATIONS OX THE EXTREMITIES 163 the forearm, and then inject 1 per cent, novocain solution, either without or with only a very small addition of suprarenin. If, on the other hand, no constricting band is applied at all., it is advisable to use 2 per cent, novocain solution + suprarenin (1 to 2 minims per c.c). In operations on the palm of the hand. 1 per cent, novocain solution is employed. It is not necessary in finger operations to inject always at the base of the finger. The only essential point is that the injection be made in healthy tissues. Thus, in operations about the nail we may inject at the level of the last phalangeal joint, and only a small quantity of solution need be used. If the area of operation be Cjuite peripheral. 1 per cent. solution will be found effective without tourniquet, in view of the minimal calibre of the nerve- branches in the afiectecl area. The following technic[ue of injection has given me satisfactory results {vide Fig. IS) : At the base of the finger and a little to each side of the middle line of the dorsum an injection point is marked (ethyl chloride or wheal anaesthesia). From these points the injection is made. Say we commence at the radial [)oint. The needle is introduced and passed a little way towards the volar .surface, \ c.c. of solution being injected in the neighbourhood of the dorsal radial nerves. The needle is then pushed on fauly close to the dorsal 164 LOCAL ANAESTHESIA bone, and another^ c.c. injected in the neighbour- hood of the volar nerves. The same proceeding is carried out on the ulnar side. Anaesthesia comes on from five to ten minutes after the injection. Any operation, either on the soft parts or on the bones, can then be painlessly carried out. The operation must not be begun until the finger-tip is quite insensitive. In small superficial foci, especially on the dorsal sur- face, it is often sufficient to infiltrate a strip on the cen- tral side of the operation area. One must always, however, reckon with irregularities of the nerve-supply, or anasto- 'voiar moses, so that it is generally advisable, in order to feel Fig. 18.— Injection of quite safe, to inject a little THE Finger. solution around the afi^ected area. It is not generally necessary to inject beneath it. In operations on the base of the fingers and up to the metacarpo-phalangeal joint the injection is carried out on either side of the metacarpal bone {mutatis mutandis), as described above for the peripheral portion of the digit, care being taken that the injection is made at a sufficient distance from the diseased area. In these cases, however, rather more than 2 c.c. of solution must be OPERATIONS ON THE EXTREMITIES 165 employed. In view also of lateral anastomoses, supplementary subcutaneous injections must be made at the sides with more dilute (1 per cent.) solution. As regards operations on the hand, it is impor- tant to bear in mind the point of exit of the median nerve at the ulnar border of the ball of the thumb. In operations about this region this point must be freely infiltrated. In general there are so many anastomoses among the nerves of the hand, both lateral and also between dorsal and volar nerves, that nothing^ can be done by interruption of conduction in single nerve-trunks. On the dorsum of the hand the ansesthetizationof any superficial operation area presents no difficulty. If the affected area be small, injection around it is sufficient ; if larger, it will be necessary to inject beneath it also. Of course, if the operation be at the periphery, the form of the injection must be semicircular or wedge-shaped, instead of circular, and with the base toward the periphery. Operations on the periphery of the palm give favourable opportunity for anaesthesia by semi- circular injection. Novocain solution (1 percent.) and suprarenin should always be employed. It is often advisable, especially if the operative pro- cedure is somewhat complicated, to apply a rubber band, not too tightly, round the forearm. Up to about the middle of the palm (reckoning from 166 LOCAL ANESTHESIA the periphery), operations on the deeper tissues (tenotomy) may also be performed in this manner. Where possible, the injection points should, in view of the sensitiveness of the skin of the palm, be in the interdigital spaces. In the central half of the palm only superficial foci should be attacked by the simple method of injection around and beneath the affected area. Dupuytren's contracture may be operated on in this way if a thorough injection is made beneath the parts to be removed. The thumb and the ball of the thumb may also be cut off from their sensory supply by this method, a free and deep injection being made at the ulnar border of the thenar eminence. Braun has recommended for larger operations on the hand a method of interruption of con- duction in the three main nerve-trunks — ulnar, radial, and median — above the wrist. The technique is not altogether simple, nor are the results, in my experience, quite certain. The method (Fig. 19) will, perhaps, in the future be superseded by Bier's venous method. The procedure is as follows : Two per cent, novocain solution is employed + 1 minim of supra- renin per cubic centimetre. Of this solution 1 c.c. is required for each nerve. Injection for the median nerve : Above the wrist, at the ulnar side of the M. palmaris longus. OPEEATIONS ON THE EXTREMITIES 167 The needle is passed beneath the muscle and pushed onwards for a distance of about 1|- centimetres. For the ulnar nerve : Three finger-breadths above the wrist, between the ulna and the tendon of the M. flexor carpi ulnaris, the needle to be passed under the tendon and inserted altogether about 2 centimetres. A circular injection ( 1 or '5 per N.mterosseus dors. Mulnaris • N.radia^is M. flexor uheti^ A.radialis \ M flexor radialis \JVmecliamis M.palm.lonff. Fig. 19. — Anesthesia of the Whole Hand by Interrup- tion OF Conduction (after Braun). cent, solution) round the forearm immediately above or below the capitulum ulnae should supplement the foregoing, and this suffices for the radial nerve. For the region supplied by the median especially the method is not very trustworthy. Finally, a few words may be said in connection with phlegmonous conditions, especially phlegmon of the sheaths of the tendons. 168 LOCAL ANESTHESIA In the first place, the surgeon cannot be too strongly warned against the use of ethyl chloride, except in the case of quite small cutaneous or subcutaneous foci. Those who have much to do with the treatment of phlegmonous processes see, far too often, cases of suppuration in the sheaths of tendons in which a small superficial incision has been previously made under cold, though any accurate differentiation of tissues is, under such conditions, quite impossible. The pain ceases or diminishes because a small amount of pus is evacuated ; the suppurative process, however, continues, and spreads deeper and deeper. Anaes- thesia by interruption of conduction, too, is only suitable for small and easily demarcated phlegmons. The more severe forms are not suitable for local anaesthesia at all. It is often quite impossible to say before operation how far such phlegmons extend, and it is always to be remembered that, apart from the obviously inflamed lymphatics of the arm or forearm, there are often microscopic bacterial infiltrations, in the neighbourhood of the phlegmonous focus, which involve serious risk of spreading infection by an injection made in apparently sound tissues. Thus, I once saw a fairly extensive necrosis of the subcutaneous fatty tissue follow injection around and incision of a so-called interdigital phlegmon — a complication which, though it was fortunately recovered from OPERATIONS ON THE EXTREMITIES 169 without bad effects, caused an inconvenient delay in recovery. As I have never, with this exception, seen any occurrence of the kind, I feel justified in assuming that infectious material was disseminated by the injection among apparently healthy tissues. In the palm, especially, morbid processes affecting the deeper tissues are, in con- sequence of the tightness of the skin in this region, but very little apparent on the surface. To what extent Bier's venous anaesthesia will supply us here with a thoroughly safe substitute it is at present impossible to say. In Bier's paper the question whether lymphangitic cords along the arm are to be regarded as contra- indicating his method is not alluded to. Even, however, if no superficial inflamed lymphatics are visible, there is always a possibility that the deeper lymph channels may be full of infectious micro-organisms. Whether this does or does not constitute a danger only further exjjerience will show. As regards the lower extremity the older methods of local anaesthesia do not suflice for any but quite superficial operations on the thigh. For Thiersch's skin-grafting the same rules apply as in the upper arm. It is, however, advisable to note the amount of fatty tissue, and if the layer of fat be well marked, to infiltrate very freely, a point, indeed, to which attention should be paid in all operations on this region. 170 LOCAL ANESTHESIA Operations on the femoral and inguinal glands are only suitable for local anaesthesia when the aifected glands are easily separable from the sub- jacent tissues. Even then free injection around and especially underneath the area of operation with 1 per cent, novocain-suprarenin solution is necessary in order to secure trustworthy anaes- thesia. As regards incision of glandular abscesses, what has been stated above concerning parulis and abscesses in cervical glands applies here also. Where the glandular tumour has been adherent to the subjacent tissues I have seldom attained a thoroughly successful anaesthesia, even when, after a superficial injection, a free infiltration after Schleich's method has been carried out during the operation. For the extirpation of a portion of the saphenous vein the procedure is similar to that given for pro- ducing anaesthesia of bone — injection around and beneath the vein after the latter has been made clearly visible by obstruction to the flow of blood within it. With the help of venous anaesthesia surgeons have now succeeded in carrying out painlessly major operations on the thigh — indeed, anaesthesia of the whole lower half of the thigh has been pro- duced. Bier has carried out three necrotomies in this way. He, however, regards it as doubtful whether the present technique will prove definitely OPERATIONS ON THE EXTREMITIES 171 effective, as the anaesthesia on the outer side of the thighj where operations of this kind have, for the most part, to be performed, is the latest and most uncertain in its onset, because the solution is injected on the inner side. Of operations on the neighbourhood of the knee- joint, those on the bursa patellae offer the most frequent opportunities for the employment of local anaesthesia. Just as in the case of the bursa olecrani, it is possible here to bring about a reliable anaesthesia by injecting with 1 or '5, per cent, novocain solution + suprarenin, provided an injection is first made as deeply as possible around the bone and followed by a circular subcutaneous injection. Removal of loose bodies from the joint has frequently been performed successfully after injection around the selected site of incision, and subsequently very free infiltration of the deeper parts. I am, of course, speaking only of bodies easily to be felt externally. If one is not sure of reaching the loose body by the first incision, it is suggested by Braun as preferable that the joint shall be filled with '25 per cent, solution, and a period of ten to twenty minutes be allowed for it to act. Similarly, in other small operations on the knee- joint (injection of irritant fluids, incision in cases of suppuration, with a view to drainage), the synovial membrane must first be rendered insensitive by 172 LOCAL ANAESTHESIA injection of an anaesthetic solution, preferably '25 to '5 per cent, novocain solution + 2 minims of suprarenin per 10 c.c. An incision can then be made painlessly, either under circular anaesthesia or under Schleich's infiltration method. Of major operations, Bier has performed several resections of the knee-joint under direct venous anaesthesia. The upper band must not be applied too close to the joint. In the leg, apart from operations on superficial foci, all operations on the anterior surface of the tibia may be carried out satisfactorily under circular anaesthesia, as above described. Amputations of the leg have been performed by Schleich and Reclus under infiltration anaesthesia. Tenotomy of the tendo Achillis can be peformed painlessly after injection around and beneath the tendon. Braun suggests the following procedure for pro- ducing anaesthesia of the whole foot : Infiltration of the subcutaneous cellular tissue all round the limb above the ankle with '5 per cent, novocain solution. The same solution is injected beneath the fascia at the anterior surface of the tibia, in the space between the tibia and fibula and behind the tendo Achillis ; finally, 4 c.c. of 2 per cent, solution are employed to inter- rupt conduction in the tibial nerve. Just above the ankle-joint, where the inner malleolus is at its OPERATIONS ON THE EXTREMITIES 173 thickest, the needle is inserted 1 centimetre inter- nally to the mesial border of the Achilles tendon, and passed straight forward until it meets the bone. It is then slightly withdrawn, and the injection made. Whether or not the method is to be depended on only further experience can show. For major operations on the leg and foot Bier uses indirect instead of direct venous anaesthesia in all cases where he wishes not to be limited in regard to the extent of the operation area, also when the site of operation is covered with cicatrices, as, under the latter conditions, the vein is difficult to find, and the anaesthesia is apt to be incomplete. The operator must wait till motor paralysis sets in — i.e., generally about fifteen minutes. Of course, all other operations on the leg and foot can also be carried out under indirect anaesthesia. Direct venous anaesthesia has the advantage that the operation can be begun almost at once. The saphenous vein is easily found anywhere in the leg {vide Figs. 5 and 6). In operations on the foot Bier recommends that a rubber bandage shall be applied to the most peripheral parts. If long incisions are necessary, the operation, may be carried out partly under direct and partly under indirect anaesthesia. The central tourniquet should be applied just above the knee, the peri- pheral a little above the middle of the leg. After 174 LOCAL ANESTHESIA indirect anaesthesia has set in the peripheral tourniquet is removed. What has been said above concerning the upper extremity holds good also for small opera- tions on the foot and toes (small phlegmons, exarticulations, etc.). Here, as there, a tourniquet may be applied to the lower third of the leg in order to deepen the anaesthesia. The operation for ingrowing toe-nail can, as already stated, be performed satisfactorily under ethyl chloride spray, if the nail be thoroughly frozen and the operation quickly carried out. For operations in the neighbourhood of the first metacarpo-phalangeal articulation the middle of the metacarpal bone is freely bathed in 1 per cent, novocain solution, the needle being entered at the dorsum. The next step is to infiltrate the tissues bordering the bone on its outer side, carrying the infiltration up to the interdigital fold between the first and second toes. Anaesthesia is more easily and more surely produced in the dorsum of the foot than in the sole. CHAPTER XII ABDOMINAL OPERATIONS The degree of sensibility to paiu possessed by the abdominal organs has been a much disputed point. It might, indeed, be supposed that the large number of operations which have been carried out under anaesthesia produced by infiltration of the abdominal wall must by now have thoroughly cleared up the matter. That this is by no means the case we may ascribe to the fact that the abdominal organs exhibit an extraordinary variability in this respect. Thus, apart from the fact that there are unusually marked diiferences between individuals, the age of the patient, the pathological condition of the organs, and the temperature, are important factors, and may help to explain the wide differences between the views put forward by different observers. According to Lennander, to whom we owe the most detailed investigations of the matter that have yet been made, all parts supplied by the sympathetic are Insensitive, sensibility to pain being a function confined to the cerebro-sj)inal nerves. According 175 176 LOCAL ANESTHESIA to Emitter, sensibility to pain is associated with the bloodvessels. His experiments on dogs (which have, of course, less inferential value than observa- tions on the human subject) revealed, in all the organs of the abdominal cavity, a sensibility to pain whose intensity depended on the richness of the part in bloodvessels. The facts of chief practical importance may be here briefly stated : 1 . The parietal peritoneum is certainly sensitive to pain, and often the mesentery. 2. The stomach, intestine, omentum, liver, renal parenchyma, and fundus uteri, are insensitive. 3. Inflammatory processes generally heighten insensibility, and this is specially the case in the parietal peritoneum. 4. In the old, sensibility is generally diminished. 5. Heduction of temperature lowers sensibility. 6. There are marked individual differences in sensibility, of which we can at present give no explanation. In regard to the question whether any given operation is one for which it is suitable to employ local anaesthesia, the following points deserve attention. It may be laid down as a fundamental principle, that only such operations should be performed under local anaesthesia as can be carried out pain- lessly to the end. I do not consider it good ABDOMINAL OPERATIONS 177 practice to make a routine use, as Schleich does, of the combined method — i.e., the employment of general anaesthesia for the more painful parts of an operation which is otherwise carried out under local anaesthesia. The patient has, in the present state of the technique of anaesthesia, the right to be operated on painlessly, and the risks of general anaesthesia, which are really not great when all is taken into coDsideration, should not be unduly exaggerated. There are, of course, exceptional cases in which the patient's condition is such that no unnecessary drop of chloroform or ether must be used. Often, however, even in such patients a rapid narcosis in the course of the operation requires as much of the anaesthetic as would suffice for the whole operation had chloroform or ether been employed with care and skill throughout. One may, of course, be forced by unforeseen emergencies to call general anaesthesia to one's aid. Thus in case of incarcerated hernia in which we are anxious, on account of pro- nounced cardiac weakness, to operate under local anaesthesia, the existence of tough adhesions may oblige us to continue the operation under narcosis. So, too, in gastrostomy, which is often performed under local anaesthesia, the stomach may be so contracted that the necessary pull upon it will cause pain. In such case, very frequently, before deciding to continue under general anaesthesia, 12 178 LOCAL ANAESTHESIA the surgeon makes trial once, or perhaps several times, whether he cannot get through without chloroform, and so causes the patient, who has probably received an emphatic promise of a pain- less operation, unnecessary sutfering. Such contrtftrnps should be avoided, if possible, and unless it is absolutelv necessarv to avoid general anaesthesia, doubtful operations of the kind should be performed throughout under ether or chloroform. The combination of local anaes- thesia with morphine-scopolamine narcosis should also be unhesitatingly rejected. I have seen a number of cases in which serious sequelte mani- fested themselves, and the number of suro-eons who have definitely abandoned the method in- creases steadily. It follows, from what has been said, that it is only a comparatively small proportion of abdo- minal operations that we can perform under local anaesthesia, those, namely, in which, after the abdominal incision, the further operative pro- cedures are confined to certain presenting organs (intestine, omentum) and no dragging or pulling manipulations of any kind are required. In some individuals, it is true, especially some old patients, it is possible to carry out manipulations in the abdominal cavity freely, and, without any special precautions, to pull on the mesentery, and so on. Such cases are, however, exceptional. It is more ABDOMINAL OPERATIONS 179 usual to find that the mere insertion of a com- press between the parietal peritoneum and the intestinal coils is painful, and that any vigorous traction on the sides of the wound with retractors is generally (probably because of the dragging on the parietal peritoneum caused thereby) found by the patient extremely unpleasant. Schleich infiltrates the abdominal organs, as he does other tissues, to the point of oedema. Those who hold, as most surgeons do, that in abdominal surgery the organs must be handled as gently as possible, can hardly approve of this procedure. One can, of course, infiltrate the pedicle of an ovarian tumour, or the line of incision in a gall- bladder which is to be opened, but operations on the ovaries or the gall-bladder involve other manipulations, such as the drawing forward of the ovarian tumour and the indispensable sounding of the gall-ducts, which are painful, and in which infiltration is of little use. Infiltration of the wall of the stomach for the purpose of a gastrostomy involves, in my opinion, risk of injury to the tissues infiltrated, and this is altogether apart from the facts that the stomach is itself insensitive, that only the act of dragging on it is painful, and that against this pain local anaesthesia leaves us powerless. Local anaesthesia, then, in abdominal operations, can do little more than render painless the in- 180 LOCAL ANESTHESIA cision in the abdominal wall. The method now usually employed is a modified form of Schleich's infiltration anaesthesia — that is to say, an infiltra- tion of the parts with somewhat concentrated solutions, which, however, is not carried to the point of causing a maximum degree of oedema, and is, if possible, completed before the beginning of the operation. This method is often combined with circular anaesthesia of particular regions. If only a small incision is required, and the abdominal wall is thin, we may employ 1 per cent, novocain solution + 1 to 2 minims of suprarenin per 10 c.c. For larger incisions '5 or '25 per cent, solution is employed, according to the quantity required for the infiltration. The method is most successful in very thin subjects, in whom, in the case of a median incision, the whole infiltration may be completed before the commencement of the opera- tion. The operator first infiltrates subcutaneously to a distance of a centimetre or two from the chosen line of incision, and follows this up with a free subfascial infiltration. In about ten minutes one can count on complete anaesthesia. Only when more room is required for the suture is it neces- sary, after division of the fascia, to proceed to a further infiltration, on both sides of the incision of the prseperitoneal tissue. The same procedure may be adopted away from the median line in ABDOMINAL OPERATIONS 181 thin subjects, if the region of operation is one in which the muscles and fasciae are very thin, as, for example, in the formation of an artificial anus, and often also in gastrostomy. The larger the quantity of fat in the abdominal wall, the more difficult is the ansesthetization, at any rate in patients whose abdominal wall is at all tense. It is then often necessary to anaes- thetize the skin itself by the wheal method over the selected line of incision. Then, after infiltration of the subcutaneous cellular tissue, the incision may be carried down to the fascia. The injecting needle — a right-angled one is not absolutely neces- sary — is then passed under the fascia and the praeperitoneal tissue infiltrated, the infiltration being continued farther after division of the fascia. If large nerves are met with in the area of operation, the solutions employed must not be too dilute (1 per cent, novocain solution). If the incision be a small one, the infiltration may be carried out to the end without change of solution. Here, too, in thin subjects, the whole or the greater part of the infiltration may be carried out before the operation is begun — e.g., in an incision at the outer border of the rectus, in which special atten- tion must be paid to the obliquely-running branches of the intercostal nerves, or in a slanting incision such as is made in cases of perityphlitis, when the ilio-hypogastric and ilio-inguinal nerves 182 LOCAL ANiESTHESIA are found running in the deeper muscular layers between the internal oblique and transverse muscles. In individuals, however, with a larger deposit of fat, an infiltration of the separate layers step by step is required. I will give here the technique for an incision in the flank, as described by Braun, merely substi- tuting novocain solution for that of cocain. Wheal anaesthesia of the skin along the line of incision, using -25 per cent, novocain solution with suprarenin. Infiltration of the subcutaneous cellular tissue in the form of a Hackenbruch's rhombus. Division of the soft parts down to the fascia. Infiltration of and beneath the external oblique muscle in the line of incision. A short period of waiting. Division of the muscle and its fascia, followed by injection of about 3 c.c. of 1 per cent, solution in a line along the lateral border of the divided external oblique (drawn outwards for the purpose), into the muscular tissue of the internal oblique and transversus as far in a lateral direction as possible. A few minutes waiting. Division of both muscles in a direction parallel to the course of the fibres. Infiltration of the now exposed praeperitoneal tissue with '25 per cent, solution over a wider area around the line of operation. Division of the peritoneum in a diagonal direction. , ABDOMINAL OPEEATIONS 183 The whole infiltration may be carried out quite well with '5 per cent, solution, only remember- ing to infiltrate specially freely the internal oblique and transversus muscles in which the nerves run. I have endeavoured to give above, in outline, the points necessary for a decision of the question whether local anaesthesia shall be employed or not. Individual peculiarities must, of course, not be left out of consideration in the matter. Of morbid processes in this region we may mention as specially suitable for operation under local anaesthesia extra-peritoneal abscesses — e.g.., large encapsuled perityphilitic abscesses, if so far softened that only a simple incision is required, also cystic tumours which merely require opening (hydatid cysts). Formation of an artificial anus and gastrostomy are also suitable for local anaes- thesia in many cases. The latter operation, how- ever, cannot be performed painlessly if there is much contraction of the organ, and this is not infrequently the case. Other simple laparotomies which do not involve manipulations in the abdominal cavity may also be performed under local anaesthesia. Operations for appendicitis are, in some clinics, frequently performed under local anaesthesia ; whether always painlessly I should not like to say. It is impossible to say beforehand, with the least 184 LOCAL ANESTHESIA approach to certainty, whether or not adhesions, generally involving the parietal peritoneum, are present. Where they exist local anaesthesia is illusory. But even in the absence of adhesions, the simple fact that the caecum is often fairly closely attached to the posterior abdominal wall, and that, in consequence, a slight pull is required to bring the appendix into the wound, may be sufficient in many cases to preclude all chance of the operation being performed under local anaesthesia without severe pain. Hernia Operations. It is necessary to distinguish between herni- otomy for strangulated hernia and the so-called radical operation. The first offers generally a very favourable field for the emj^loyment of local anaesthesia. The reason for this is not very clear. We must not attach any great significance in this matter to the mental attitude of the j)atient, who is, of course, grateful for the prospect of relief from his suffering, for in the case of pains in other regions of the body, far surpassing in intensity those proceeding from a strangulated hernia, we meet with no such psychic analgesia during the operation. The diminution of sensibility to pain noticed in strangulated herniae must be almost ABDOMINAL OPERATIONS 185 entirely attributable to a disturbance of nutrition in the nerves which pass through the constrict- ing ring to the hernial sac, which disturbance is to be attributed partly to compression of the nerves at the point of constriction, and partly to a blood stasis aifecting the w^hole strangulated area. Where the strangulation has existed for some time, and especially in old persons, it is often only necessary to anaesthetize for the skin incision in order to be able to perform the whole opera- tion painlessly. The shorter the duration of the strangulation has been, the less can we count on the presence of this condition of diminished sensi- bility. Where the lowering of sensibility is marked, it often affects the parts surrounding the constricting ring to such an extent that it is possible, in addition to the herniotomy, to per- form painlessly a radical operation, and this with only a slight injection, though, in the absence of strangulation, it is not an easy matter to perform a radical operation under local anaesthesia on, say, an inguinal hernia. The hernial contents in a strangulated hernia cannot be directly anaesthetized ; the breaking- down of adhesions, however, between the hernial sac and its contents is rendered painless by anaesthetization of the sac. Dragging and pulling the organs within the sac causes pain. The larger the hernia the sooner will the operator 186 LOCAL ANESTHESIA find himself compelled to have recourse to such manipulations. In umbilical hernias the distribution of the nerves involved — converging radially from all sides upon the umbilicus — is a very simple one. The circular method is, therefore, generally the best to employ here, the solution ("25 to 1 per cent, novocain-suprarenin solution) being injected all round the umbilical ring, first under the fascia, and then in the subcutaneous cellular tissue. In large irreducible hernias with fatty abdo- minal walls the method is often insufiicient. Here, after a surrounding subcutaneous injection, the hernia must be opened by a curved incision over its greatest circumference with the aid of Schleich's skin-wheal anaesthesia, using the fingers as a director. The sac must then be more widely spread, and the prseperitoneal tissue surrounding the neck of the hernial sac freely infiltrated from the wound. Local ansesthesia is, however, only of limited applicability to operations on umbilical hernias. We have seen that it is far easier to carry out a hernia operation under local anaesthesia if the hernia be strangulated. Even in strangulated cases, however, patients with tense abdominal walls often prove unsuitable subjects for local anaesthesia. If the parts are much stretched in suturing, local anaesthesia is often inefiective. ABDOMINAL OPERATIONS 187 The best subjects are women with lax abdominal walls. Often, too, a very large hernia, or very strong adhesions, render a case unsuitable for local anaesthesia. It must not be understood that it always fails in such cases, but rather that it cannot be regarded as an absolutely certain method, and should therefore only be employed when very strongly indicated. Finally, local anaesthesia must be employed with great caution in patients with a large deposit of fat in the abdominal wall. Here it is not so much any failure in the anaesthesia that is to be feared as the tendency of adipose tissue to necrosis, for even the most unirritating injection involves some injury to tissue, if only a minimal one. What has been said above concerning um- bilical hernias applies also to hernia of the linea alba. In inguinal hernias the conditions are much more compHcated, seeing that in the neighbour- hood of the inguinal canal there are various nerve- trunks of considerable size crossing each other in different directions. The figure given on the next page shows the distribution of the separate nerves. The internal inguinal ring, in whose neighbourhood the surgeon is bound to work in performing a radical opera- tion, which is nowadays ahuost always super- 188 LOCAL ANESTHESIA added to a herniotomy, is so situated, as the figure shows, that conduction must be interrupted in all the nerves in order to render it and its neighbourhood anaes- thetic. As a rule anaesthe- sia is most easily at- tained in cases where the inguinal hernia is strangulated. The operator first injects deeply around the neck of the hernial sac with '5 or 1 per cent, novocain solu- tion. The subcuta- neous tissue is then infiltrated alono^ the selected line of in- -DisTRiBUTioN OF Nerves cisiou, the skiu haviug Inguinal or Crural t . t been previously anses- FiG. 20. in the inguinal or Eegions (after Braun). 1. N. genito-femoralis. 2. N. sper- thotized by the whcal maticus externus. 3. N". lumbo- ™„j.i^ /I '-P -j-k U inguinalis. 4. N. ilio - inguinalis. metnOQ II ine aO- 5. N. ilio-hypogastricus. 6. Rami rlnininnl wall i*g \7(^r\T cutaneiant. N. intercostalis xii. UOmmai Wail IS Very fatty. The tissues are then divided down to the aponeurosis of the external oblique muscle, the incision being ex- tended sufficiently to expose the neighbourhood of the external inguinal ring. The needle is ABDOMINAL OPERATIONS 189 then inserted through the aponeurosis a little above the constricting ring and solution is injected, at first in a direction parallel to and immediately above Poupart's ligament, then at a point somewhat above and external to the first, where the internal oblique and transversus muscles pass. This will anaesthetize the hernial sac sufficiently to allow of its being opened. If it is preferred not to open the sac until the neigh- bourhood of the external ring is completely ex- posed, it is necessary either to wait or to divide under continuous infiltration, first the aponeurosis at the external inguinal ring, and then the con- stricting ring itself. There follow now replace- ment of the contents of the sac, further infiltration of the whole prseperitoneal tissue, ligature of the hernial sac, and radical operation. For the radical operation on free hernias — I have experience only of Bassini's method — Cush- ing's method of endoneural injection of the separate nerve- trunks was formerly often em- ployed. On account of its troublesomeness, how- ever, it never became really popular. Meanwhile, in consequence of our ability to employ nowadays more concentrated anaesthetic solutions without any risk, a method has been successfully devised which has been already adopted by a number of surgeons {Braun, Nast- Kolb, etc.), and which may be regarded as, to a 190 LOCAL ANESTHESIA certain extent, a successful outcome of the many endeavours that have been made to render in- guinal hernias operable under local anaesthesia. Its simplicity, too, will probably materially con- tribute to secure its adoption in practice. V -> Fig. 21. — Method of Anesthetization for the Eadical Operation on an Inguinal Hernia. The needle is first inserted (after formation of a cutaneous wheal) 1 centimetre above the end of the selected line of incision, and the subcu- taneous tissue underneath and around that line IS infiltrated with '5 per cent, novocain-supra- ABDOMINAL OPERATIONS 191 renin solution. From the same point of injection the fascia is penetrated, and the needle passed through the whole thickness of the abdominal wall, infiltrating the deeper tissues, first in a median direction, then laterally towards Poupart's ligament. The injecting needle is now inserted a little below the external inguinal ring (again after formation of a cutaneous wheal), the spermatic cord is raised and injected, then, while the needle is either passed on through the external inguinal canal or made to penetrate the aponeurosis a little above the external inguinal ring, the operator injects, both in a median and a lateral direction from the spermatic cord, the deeper tissues of the abdominal wall. After waiting a certain time, the operation may be begun. From 30 to 50 c.c. of solution are usually employed. It is always advisable to infiltrate very freely. In subjects with very fatty abdominal walls the method is not a very sure one. Unless there is some special ground for avoiding a general anaes- thetic, operators who are not thoroughly practised in local anaesthetic methods had better forego the attempt to operate under local anaesthesia in these cases. If local anaesthesia is to be employed, the separate layers must be infiltrated step by step after Schleich's method, some waiting time being allowed after each successive step of the process, and special attention being paid to the prae- 192 LOCAL ANESTHESIA peritoneal tissue. The method cannot be regarded as a perfect one, and though, as a rule, when carried out correctly, it enables the surgeon to operate painlessly, vigorous dragging on the spermatic cord, which cannot in some cases be avoided, is not always quite painless to the patient.* What has been said as regards Bassini's radical operation applies also to the Alexander- Adams operation in women. In herniotomy for strangulated femoral hernia the method of circular injection is effective. The injection is made, first subcutaneously, then into the deeper parts, special care being given to the injection of the prseperitoneal tissue at the neck of the hernial sac. Exposure and ligature of the sac can then be carried out painlessly, provided there be not too great a development of fat. If \^ radical operation is to supplement the herniotomy, the parts to be fixed in contact, and again especially the prceperitoneal tissue, must be freely infiltrated. The infiltration can only be carried out after complete exposure of the fascia, owing to the presence of the large femoral blood- vessels in this region. * The method failed in a case of congenital hernia in an adult. The failure will appear explicable on a study of the anatomical conditions present in such cases. CHAPTEE XIII OPERATIONS ON THE ANAL EEGION AND GENITO-URINARY TRACT The mucous membrane of the urethra possesses a fairly high degree of sensibility to pain, which is, however, more marked in the posterior than in the anterior portion of the urethral tube. The vesical mucosa is, in normal conditions, very slightly sensitive, but when inflamed may exhibit a high degree of sensibility. For anaesthetizing the human male urethra, with a view, for instance, to the carrying out of a difficult catheterization or of a cystoscopy, we have found the following method eflective : With an ordinary gonorrhoeal syringe of about 5 c.c. capacity, 30 to .50 c.c. of 2 per cent, novocain solution (the addition of suprarenin is not abso- lutely necessary) are slowly injected into the urethra, and their escape prevented by placing round the base of the glans a rubber ring or a piece of bandage. A certain amount of the solution usually finds its way into the bladder. 193 13 194 LOCAL ANESTHESIA The greater part, however, remains in the dis- tended urethra. In ten minutes the solution may be allowed to flow away, and the catheter or cystoscope can then almost always be introduced without causing pain. If a stricture is present, suprarenin is freely added to the solution, and as much of the latter as the urethra will hold is injected. It is left to act for at least fifteen minutes in order that the supra- renin may exert its full detumefying effect on the mucous membrane. It will then generally be found possible to pass a fine catheter. In the subsequent dilatation the same procedure is adopted ; the results, however, as regards anaes- thesia are not so certain. According to Reclus, internal urethrotomy can be painlessly performed after injection into the urethra of 1 per cent, cocain solution. This solution would now be replaced by 2 per cent, novocain-suprarenin solution. In external urethrotomy the urethra must first be anaesthetized in the manner above described, after which the operator must inject all round the operation area, special care being given to the injection of the deeper parts. It is seldom necessary to anaesthetize the female urethra. Occasionally I have removed small growths from the neighbourhood of the meatus OPEEATIONS ON THE ANAL EEGION 195 urinarius under circular anaesthesia. If the whole urethral mucous membrane is to be rendered insensitive, it is only necessary to dip a pledget of cotton- wool wrapped round a thin rod of some kind in 2 per cent, novocain solution, and place it in the urethra for a few minutes. The vesical mucous membrane can also be rendered insensitive without much difficulty. The bladder is filled, according to its capacity, with or without previous ansesthetization of the urethra, with '25 to "5 per cent, novocain- suprarenin solution, which is then left to act for at least twenty minutes. If the vesical capacity is very small, Braun advises that the operator should cautiously allow the solution to flow in under slight pressure from any irrigator. The vesical spasm then gradually gives way, so that the bladder, after twenty or thirty minutes, has generally regained its full normal capacity. The suprapubic operation should not be attempted under local anaesthesia save in thin patients with very lax abdominal walls, in whom no stretching of the muscles is necessary. The vesical mucous membrane must first be anaesthetized, and the site of the abdom- inal incision then infiltrated in the ordinary way after Schleich's method. Of operations on the penis, that for phimosis is one of the most favourable of all operative 196 LOCAL ANESTHESIA procedures for the employment of local anaes- thesia. If E-oser's operation is to be performed, the whole line of incision should be freely infiltrated between the inner and outer surfaces of the prepuce with 1 per cent, novocain solution. Further infil- tration should be made during the process of incision ; special attention must be paid to the in- jection at the fold between the glans and the inner prseputial surface, if the so-called lobule of Roser is to be formed. If the infiltration be sufiiciently free, complete anaesthesia is always attained. If, as is now more often the case, circumcision is to be performed, this can always, so far as my experience goes, be carried out successfully under circular anaesthesia. The surgeon injects freely from one or two points all round the organ at the level of the sulcus coronarius, using for the pur- pose 1 per cent, novocain-suprarenin solution ; then, after retraction of the prepuce, he infiltrates specially the very sensitive frenulum. If the prepuce cannot be sufficiently retracted, it must be slightly incised after full infiltration of the site of incision. If, then, sufficient time (about ten minutes) is allowed, the operation can generally be painlessly performed. Before commencing to operate the surgeon should ascertain by means of a surgical forceps whether the inner praeputial surface, which is much more sensitive and more OPERATIONS ON THE ANAL REGION 197 difficult to anaesthetize than the outer, is also thoroughly insensitive. In the operation for paraphimosis the most practical method is to infiltrate freely, after Schleich's method, the selected line of incision. If the deeper layers are also injected, further infiltra- tion during the operation is not necessary. If a supplementary circumcision is determined on, the surgeon may, as recommended by Braun, inject round the organ immediately on the proximal side of the constricting ring, and then round the line between the latter and the glans under the retracted praeputial mucous membrane. Reclus has performed amputations of the penis under infiltration anaesthesia. The operation should present no difficulties for local anaesthesia if the penis be infiltrated in its whole circum- ference with 1 per cent, novocain solution, either on the proximal side of the line of amputation, or at the line itself Superficial operations on the scrotum may be performed under simple circular anaesthesia. Puncture of a hydrocele may be made painless by Schleich's infiltration of the site of puncture. During the infiltration, as during the puncture itself, the skin of the scrotum is drawn tightly back. If an irritant fluid (tincture of iodine) is to be injected, the cavity must be filled, after the hydrocele fluid has drained away, with '25 per 198 LOCAL ANESTHESIA cent, novocain solution, and the trocar left in situ. The solution must be left to act for about fifteen minutes, and then allowed to flow away. The irritant fluid can then be injected without pain. For larger scrotal operations, such as operations for hydrocele or castrations, anaesthesia by inter- ruption of conduction is the best method to employ. Novocain solution (1 per cent.) with suprarenin should be employed. If a greater quantity of solution than usual is required, the additional quantity should be in '5 per cent, strength. The spermatic cord is first seized as high as possible between finger and thumb, pressed against the tightened skin, and injected with several cubic centimetres of solution. Its surroundings are then freely injected. This injection renders the testicle and its coverings insensitive in about ten minutes. If the operation is merely on a hydrocele, a free infiltration around the spermatic cord will suffice, the scrotal incision being then made painless by the circular method, or by subcutaneous injection beneath the line of incision. In castration the whole connective tissue of the scrotum must be infiltrated in a plane perpen- dicular to the spermatic, and at as high a level as possible. Owing to the great laxity of the skin, two points of injection generally suffice, one for the injection into the spermatic cord, and another OPERATIONS ON THE ANAL REGION 199 at the posterior surface of the scrotum at the root of the cord. The ansesthetization of these middle parts often presents difficulties owing to the great laxness of the tissues, which enables them to take up a large quantity of solution. A free infiltra- tion here with '5 per cent, solution is advisable. If after fifteen minutes this region is not com- pletely anaesthetic, the skin must be anaesthetized by the wheal method. The procedure is com- pleted by an infiltration of the raphe between the two testicles. If the technique is carefully and correctly carried out, the surgeon can count on a painless operation. Operations of every kind on the female ex- ternal genital organs — e.g, suture of ruptured perineum, incision of suppurating glands of Bar- tholini, cauterization of tumours, etc. — can be performed satisfactorily under local anaesthesia. Colporrhaphy also can be very successfully per- formed under circular submucous injection, only, however, in persons in whom distension of the vaginal orifice by the speculum is borne without pain. Many multiparae suffer no pain, either from the introduction or manipulation of specula, or from traction on the uterus with forceps. In such women operations on the not very sen- sitive portio vaginalis of the cervix can be carried out after circular injection of a few cubic centi- metres of an anaesthetic solution. Vagina fixations 200 LOCAL ANESTHESIA have also been frequently performed lately under local anaesthesia. Operations on the rectum constitute one of the most important fields for local anaesthesia. Bier is quite right when he pronounces it a mistaken practice to employ general anaesthesia for the minor surgery of the anal region unless it is for Sphincter anl externus Fig. 22. — Anesthetization of the Anal Eegion. some reason specially indicated. Local anaesthesia gives excellent results in operations for fissure and for haemorrhoids, and in dilatation of the sphincter ani. I use the following method, de- scribed by Braun, for the anaesthetization of the whole anal region, and find it always effective (see Fig. 22). Four injection points are marked round the anus, each about 1 centimetre from the anal OPERATIONS ON THE ANAL REGION 201 border. An index-finger is then passed into the rectum ; with care this may almost always be done without causing pain. If in the given case the parts are too sensitive to admit of this, it is pos- sible, after some practice, to dispense with the introduction of the finger. The needle is then introduced at the four injection points in succes- sion and passed along the inner aspect of the external sphincter, infiltrating as it goes (1 or •5 per cent, novocain solution), until the finger in the rectum feels the submucous swelling caused by the injection. Finally, a subcutaneous injec- tion is made around the anus. As a rule, after five to seven minutes it is found possible to dilate the sphincter without pain, and when this is so any operative procedure about the anal region may be embarked on without mis- giving. Most cases of anal fistula are suitable for opera- tion under local anaesthesia, particularly if the fistula be internal to the sphincter. Braun's failure to get good results in operations on periproctitic abscesses is to be attributed to his use of too dilute ('25 per cent.) solutions. I always employ 1 per cent, novocain-suprarenin solution, and in- clude the fistulous sinus or the abscess in the area of injection. Owing to the lax condition of the tissues in the anal region, which enables them to absorb considerable quantities of fluid, large doses 202 LOCAL AN^STBESIA are often required. I have, however, never seen any untoward effects. It need hardly be said that major operations, such as the removal of carcinomata, are, in this region, not suitable for local anaesthesia. INDEX Abdomen, operations on the, 175 • 92 Abdominal cavity, sensibility, 176- 80 Abel, investigations, 42 Abscesses : encapsuled perityphilitic, 183 extra-peritoneal, 183 glandular, 157-58, 170 lymphadenitic^ 146 periosteal, 131-32 periproctitic, 201 Abscesses, puncture of, 100, 104, 141-42 Achilles tendon, 172-73 Adenoid vegetations, removal, 120- 22 Adrenalin, 31, 42 Air-bubbles in veins, 71 Alffi nasi, 118 Alcohol, 78 Aldrich, investigations, 42 Alexander-Adams, operation of, 192 Alkali, free, effect on suprarenin preparations, 45-46, 82 Alkaline solutions, 79 Alveolares, rami, 129, 132 Alveolaris inferior, nervus, 10, 66, 85, 103, 137-42 Alypin, use of, 25, 28, 29, 31, 57, 114, 119-20, 122, 124, 128. 149 Alypin-suprarenin solutions, 122, 148 Ammonia, 44 Amputations, 67, 73,102-3. 160-61, 172 Amyl-nitrito, 26 Anaemia by cocain, 18-19, 27-28; cedema produced by, 42 Anaesthesia dolorosa, 15, 20 Ansesthyl, 3 Ansestol, 36 Anal region, anesthetization of the, 8, 193-202 Analgesia, circular, of Hacken- bruck, 64-66, 98-99, 106-7, 111, 141-45, 148-49, 152, 172, 180, 186, 192, 199; dosage of syn- thetic suprarenin for, 47 Anastomoses, 129, 130, 138, 140, 145, 164, 165 Angioma, 36 Antrum of Highmore, 136-37 Anus, artificial, 181, 183 Aorta, 74 Aponeuroses, 101 Appendicitis, 183-84 Applicators, 122 Aran, cited ^ 5 Arm, veins in the, 89-90 ; upper, operations on, 158 59, 161, 168 Arnott, 2 Arterenin (arterenol), 44 Arterial anfesthesia, 74 Arterial, sclerosis, 50 Articular capsules, 104 Asepsis, 60, 62, 125 Auditory meatus, external, 111-13, 115, 117 Auricularis magnus, nervus, 106, 111, 145 Auriculo-temporalis, nervus, 106, 111 Axillary glands, 153 Axillary region, ojjerations on, 157 j IJandage, Esmarch, 12, 86 j liartholini, glands of, 199 ji Basilica vena, 86, 89-90 203 204 LOCAL ANESTHESIA Bassini, operations on free hernias, 189-92 Benzine, 107 Bier, method of venous ansesthesia, 11-12, 41, 60, 67-73, 79, 86-92, 132, 147, 151, 157, 161, 166, 169-73, 200 Bladder, anaesthesia of the, 25, 55 Boils, 52, 53, 100, 112, 152 Bone, anaesthesia of, 103, 104, 117 132-33, 154-55, 164, 170 Bone-marrow, infiltration, 69 Boric acid, 43 Bostely, observations, 127 Bouisson, method of anaesthesia, 5 Brachial plexus, 158 Brain, insensibility of the surface 107 Braun, method of anaesthesia 2 9, 11, 15, 16, 19, 20, 104, io7, 112, 118, 139-40, 143, 144, 159 166-67, 171, 172, 182, 189-90.' 195, 197, 200-2; on use of cocain, 25, 27, 28 ; on use of ether, 35, 39 ; on eflTects of liga- ture, 38, 40 ; on use of suprarenal preparations, 42-45, 47-49, 80-82; attack on Schleich's method, 59 ' Breast, tumours of the, 153-54 Bromethyl, 3 Bronchocele, removal, 147-48 Briming, cited, 29 Buccal cavities, operations on, 119- 23 Bulb, suture of wounds of the, 126 ; enucleation of the, 127 Biinte, cited, 130, 140 Bursa olecrani, 159, 171 Bursa patellae, 171 Bursae, subdeltoid, 158 Byk, 42 Caecum, the, 184 Caffeine used hypodermically, 26. 28 Camphor, use, 26, 28 Cancerous growths, 100, 101 Cannula, use of, 70, 79, 90, 128 Canthus, inner, 123 Carbolic acid, 63, 114 Carbonic acid, 6, 36 Carbuncles, 53, 100, 152 Carcinomata, 144, 202 Carious foci, 155-56 Cartilage, anaesthesia of, 103-4, 118 ; resection of, 155 Castrations, 198-99 Catgut, 60 Catheterization, 193-94 Cauterization, 125, 199 Cephalic vein, 89 Cerebral bloodvessels, action ot cocain, 21 Cerebro-spinal nerves, sensibility, Cervical glands, 145-46, 170 Cervical region, operations on the, 145-52 Chalazia, 125 Cheek, operations on the, 143 Chemical factors, Scheich's view of use, 41-42 Chemical means of producing local anaesthesia, 4-12 Chemosis, 126 Children, operations on. Biers precautions, 70 Chlorethyl, use of, 3, 33-35, 39, 52-54, 94, 131-32, 163, 168, 174 Chlormethyl, 36 Chloroform, anaesthesia by, 5, 6, 76,177 -^ ' ' Choana, appendage to the, sensi- bility, 121-22 Cicatricial tissue, 102 Circular anaesthesia. See Anal- gesia, circular. Circumcision, 196-97 Clavicle, operations on the, 155 Cocain, use of, 6-8 ; substitutes for, 11, 18-19. 27-31 ; action of, 19- 21, 48; solutions, Schleich's formulae, 22-23, 57, 59; sterili- zation of, 26-27 ; dosage, 49, 54, 55, 65, 132, 133, 149, 194; anode used with, 51; effect on the tissues, 60; use in arterial anaesthesia, 74; for eye opera- tions, 124-25 Cocain, crystals of, 126 Cocain-adrenalin solution. 114 Cocain-chlorethyl, 38 Cocain-poisoning, 21-26, 55, 119- 20 INDEX 205 Cocain-suprarenin solution, 121, 126, 127 Cold, anaesthesia produced by, 2-3, 31-36, 38-39, 52-54 Colporrhaphy, 199 Combined anaesthesia, 76 Compression of nerves, local anes- thesia produced by, 1-2 Conduction anaesthesia, method of, 7, 9-10, 50, 63-68, 84-85, 93, 95-98, 118, 132, 133, 138-39, 143- 44, 162-63, 166-67, 198 Conjunctiva, 29, 54, 123-25 Contracture, Dupuytren, 166 Contractures, reflex, 56 Convulsions, 48 Cord, spermatic, 191-92, 198-99 Cords, lymphangitic, 169 Corks, india-rubber, 44, 80 Corning, monograph on use of co- cain, 7 ; method of regional anaesthesia, 9 ; on ligature, 40 ; method of conduction anaesthesia, 63 ; experiments, 162 Coronoid process of the lower jaw, 139 Cortex, cerebral, action of cocain on, 21 Cotton-wool pledgets, use of, 112- 14, 120, 121, 122, 134, 195 Crile, operation on the shoulder, 158 Cushing, method, 67, 189 Cutaneus antebrachii, nervus. 9, 89-90 Cutaneus colli, 145 Cystoscopy, 193-94 Cysts, hydatid, 183 Dastra, cited, 26 Dental plexus, 129, 130 Dental surgery, use of the galvanic current, 51 ; use of suprarenin novocain, 82; practical import- ance of anaesthesia in, 131-43 Dentalis, nervus, 132 Dentine, operations on, 133-34 Desault cited, 2 Deschamps' needles, 87 Diffusion anfesthesia, 98, 99, 132 Direct an;cstlie.sia, 69, 71, 92 Dogs, experiments on, 176 Dorsal nerve, 162-65 Dorsum, the, 89, 163, 165, 174 Drainage anaesthesia, 16 Due, Le, 4 Dupuytren, contractiire, 166 Dura mater, sensibility, 107 Ear, operations on the, 111-18 Ear-drum, sensibility, 114 Eichen, method, 112 Elastic ring, use, 162 Elbow, operations on the, 90, 158- 59, 161 Electric current, anaesthesia pro- duced by, 4, 51 Embolism, 71 Empyema, evacuation of, 154 Endermal injection, 13, 17 Endoneural injection, 10, 64, 67, 158, 189 Enucleation of the bulb, 127-28 Eosin, solution of, 37-38 Epiglottis, 150 Epirenan, 42 Epithelium, corneal, danger of in- jury to, 123, 124 Erythroxylin, antesthesia by, 6-7 Esmarch tourniquet the, 12, 86 Ether, use of, 2-3. 5. 32-33, 35, 76, 107, 177 Ethnoidal nerve, 109, 118 Ethyl chloride. See Chlorethyl. Ethylene chloride, anaesthesia by, 3 Eucain, use of, 10, 19, 27, 28, 31, 124, 128 Exarticulations, 157-58, 174 Extremities, operations on the, 2, 157-74 Eye, operations on the, 11, 111, 123-28 Face, operations on the, 97, 110- 11 Fangs, resection of, 133-34 Fascia muscle, 101, 102 Fauces, the, 151 Fehr, Dr., 123 note Femoral vein, 89 Femoral glands, 170 Femur, condyle of the, 89 Ferric chloride, 43, 45 Fibula, 172 206 LOCAL ANESTHESIA Fingers, ansesthesia of the, 10, 40, 82, 103; nerves of the, 66-67; Oberst's method of interruption of condiiction in, 161-63; techni- que of injection, 163-64 Fissure, operations for, 200 Fistula, anal, 201-2 Flank, the, technique for an in- cision, 182-83 Flexor carpi ulnaris, M., 167 Foci- carious, 155-56 cutaneous, 168 on the hands, 164, 166 on the leg, 172 osteomyelitic, 161 Foci, operations for, 131, 142, 158 Foot, nerves of the, 10 ; ansesthesia of the, 172-74 Forceps, 199 Foramen incisivum, 130 Foramen infraorbitale, 130 Foramen mentale, 138 Foramen palatine, 130 Forearm, operations on the, 66, 73, 91-92, 158-61, 168 Forehead, operations on the, 105-9 Foreign bodies, removal, 98, 101, 125 Freund, operation by, 155 Frey, observations of, 150 Frontal sinus, trephining, 109 Frontalis nervus, 106 Fundus uteri, sensibility, 176 Furuncles, 64-65, 98, 110, 113 Galea, the, 107. 108 Gall-bladder, 179 Ganglion spheuo-palatinum, 130 Gangrene, 50, 70 Gastrostomy, 177, 179, 181, 183 Genito-femoralis, nervus. 188 Genito-urinary tract, operations on, 8, 193-202 Glands — axillary, 163 Bartholini, 199 cervical, 145-46, 170 femoral, 170 inguinal, 170 thyroid, 147 Glandular abscesses, 157-58 Glosso-pharyngeal nerve, 113 Gluteal region, 96 Gonorrhoeal syringe, 193 Goyanes, experiments, 74 Gumboils, 153-54 Haab, observations, 126 Hackenbruch, method of circular anaesthesia, 10, 63, 64, 98-99, 147-49 ; rhombus of, 182 Hacker, von, cited, 3 Haemorrhoids, 200 Haike, observations, 111 note, 120 note Hall, method, 10 Hallstedt, method, 10, 139 Hand, anaesthesia of the, 10, 73, 161, 163, 165-69 Head, operations on the, 105-144 Heidenhain, method, 107-8; Heinze, method, 16 Henbane, 5 Hernia — congenital, 192 note free, 189-92 incarcerated, 177 inguinal, 67, 185-86, 188, 190 linea alba, of the, 187. strangulated, 184-89, 192 umbilical, 186 Hernia, operations for, 184 92 Herniotomy, 184-85, 188 Hertzog, and the galvanic current, 51 Highmore, antrum of, 136-37 Hocher, cited, 60 Hochst, preparations by, 42-46 Hoffmann, preparations by, 45, 46 Holocain, 124 Homorenon, 44-45 Hlibner, 139 Hunter, anaesthesia by cold, 2 Hydatid cysts, 183 Hydrocele, puncture of, 55, 197- 98 Hydrochlorate of cocain, 18 Hydrochloric acid, 43, 45, 82 Hydrocyanic acid, 6 Hyoid bone, 150 Hyothyroid membrane, 150 Hyperaemia, 28, 126 Hyperaesthesia, 33 . INDEX 207 Hypotonic solutions, 14 Hyj)odermic injection, 6 17 Ilio-hypogastric nerve, 181, 188 Ilio-inguiual nerve, 181, 188 Indian liemp, 5 Indigo carmine solution, 69 Indirect amesthesia, 69, 72, 90 Infants, cocainization of, 26 Infiltration antesthesia, Schleich's method, 8-9, 41-42, 46, 47, 56-65, 67, 83-85, 87, 97-98, 117-18, 120, 122, 132, 141-44, 146, 153-55, 158, 160-61, 170, 172, 179-80, 191-92, 195, 197 Infiltration pain, 19 Inflamed tissues, injecting into, 85 Infi-aorbital foramen, 129 Infraorbital nerve, anesthesia of the, 10, 106, 129-30, 136 Inguinal glands, 98, 99, 101, 170 Inguinal hernia, 67, 185-86, 188- 90 Inguinal regions, nerves of the, 188 Injection — endermal, 13 endoneural, 10, 158, 189 perineural, 10 subconjunctival, 124, 126 subcutaneous, 105-6, 128, 171 subgingival, 138, 140-41 submucous, 128 technique for conduction antesthesia, 85-86 ; for dental surgery, 134-35 ; for circular angesthesia, 148-49 Instillation, 125-28 Intercostal nerves, 181, 188 Intestine, sensibility to pain, 176, 178 Intratrochlearis nervus, 123 Intravenous injection, 48 Iodine, 55, 107, 197 Iridectomy, 124 Iris, anaiSthesia of the, 125-26 Iris, prolapse of, 125 Irritant fluids, injection, 104, 171, 197 Lschfeniia of tissues, 58, 60-61 Isotonic solutions, 14 Jaw, lower, anaesthesia of the, 103, 138-43 ; nerves of the, 138 Jaw, upper, nerves supplying the 130 Karger, cited, 36 Klapp, experiment in ligature, 40 Knee-joint, operations on the, 171- ^72 Kofmann, discoveries, 2 Kolb, method, 189-90 Roller, discovery of, 7 Koryl, anaesthesia by, 3 Krogius, method, 10 Kuehnen, 35 Lachrymal sac, operations, 122-23 Lamella, 132 Landerer, 7 Laparotomy, 76, 183 Larry, 2 Laryngeal mucous membrane, anae- thesia of, 149-50 Laryngeus inferior nervus, 150 Laryngeus superior nervus. 150, 151, 152 Larynx, anaesthesia of the, 7, 149, 151-52 ; extirpation, 151 ; nerves of the, 150 Leg, veins of the, 87-89; anaesthesia of the, 161 ; operations, 172-74 Lennander, observations, 175 Liebreich, method, 15 Ligaments, sensibility, 104 Ligation, Heidenhain's method, 107-8 Ligature, anaesthesia by, 40-41 ; of the fingers, 67 ; on a vein, 90 Linea obliqua, interna, 139 Lingual nerve, 137-140 Liugula, the, 137 Lip, anaesthesia of the, 118, 128 Liver, sensibility to pain, 176 Lobule of Roser, 196 Lossen, discovery of cocain, 18 Lucius, cited, 29 Lurnbo-inguinalis, 188 Lupus of the cheek, 97, 110-111 Lymphadenitis, 98 Magnet operations, 126 Malleolus, inner, 89, 172 208 LOCAL ANESTHESIA Mandragora, 5 Mandrake-root, 5 Manz, method, 10 Mastitis, suppurative, 153 Mastoid process, 112, 113, 117 Matas, cited, 131 Maurel, on use of cocain, 22 Maxilla, broken, suture of a, 142, 143 Maxilla, lower, nerve supply of the, 137-38, 142 Maxilla temporalis, 109 Maxillae, tuber, 129, 134 Maxillae, upper and lower, opera- tions on, 128-29, 130-31 Meatus urinarius, 194-95 Median nerve, anaesthesia of the, 166-67 Median vein, 89, 90 Medulla, infiltrating the, 69 ; sensi- bility, 102-3 Meister, cited, 29 Membrana hyothyroidea, 150 Membrana tympani, sensibility of the, 113-14 ; anaesthesia of the, 115-17 Mental foramen, 143 Mentalis, nervus, 106, 137-38, 140- 42 Merck, preparations by, 42 Mesentery, 76 ; sensibility to pain, 176, 178| Metacarpal bone, 164, 174 Metacarpo-phalangeal joint, 164, 174 Metethyl, anaesthesia by, 3 Methyl chloride, anaesthesia by, 3, 36 Monochlorhydrate of benzoyl, 28 Moral, cited, 129 Morphia, 6, 57, 148 Morphine salts, 5 Morphine-scopolamine narcosis, 178 Motor nerves, effect of cocain, 20- 21 Motor paralysis, 71, 72, 173 Mouth, floor of, operations on, 143 Mucous membrane, anaesthesia of the, 5, 16, 54-56, 96, 109, 120 ; operations on, 11 ; use of cocain on, 25, 29 ; use of novocain and alypin, 31 ; buccal, 34-35, 134 Miiller on dosage of suprarenal preparations, 49 Muscles, insensibility to pain, 102 Mydriasis, 29 Nasalis ext., nervus ethmoidalis, R., 106 Nasopalatinus, nervus, 130, 135 Neck, boils on, 152 Necrosis, 15, 187 Necrotomy, 170-71 Needles, 78-79 Deschamps', 87 hollow, 94-95 injection of, 90 right-angled, 181 Nerve-trunks, anaesthetization of, 62-68, 71, 83-85, 97-99, 160 61 Neugebauer, cited, 50 Niemann, discovery of cocain, 7, 18 ; method, 115, 116 Nirvanin, 27 Nose, operations on the, 7, 118-19 Novocain, use, 11-12, 25, 27, 29- 30, 41, 55, 119-20, 124. 137 ; dosage, 49, 65, 69-70, 91-92, 95- 97, 100, 102, 104, 110, 122, 128, 133-34, 142, 143, 145-46, 181, 186, 188, 190-91, 195-98, 201; effect on the tissues, 60, 133 ; sterilizing, 80 Novocain-suprarenin solution, use, 109, 120, 127-28 ; dosage, 112- 17, 133-36, 139-40, 147-52, 154- 55, 159, 163-67, 170-72, 182-83, 193-201 Novocain - suprarenin tablets, Braun's, 80-82 Oberst, method, 10, 30, 40, 66-67, 162-63 Occipitalis major, nervus, 106 Occipitalis minor, nervus, 106 CEdema, artificially produced by Schleich, 8, 11, 41-42, 58, 61, 83- 84, 141, 179-80 ; pulmonary, 48 ; pressure cedema, 95 ; in dental surgery, 134 (Esophagus, 120 Oily solutions, use, 125 Olecrani, bursa, 159, 171 Oliver, investigations, 42 INDEX 209 Omentum, sensibility, 176, 178 Ophthalmology, anaesthetics used in, 7, 27-29 Opium, use, 5, 149 Oppel, experiments, 74 Orthoform, 27 Osmotic tension, 4, 11, 13-17 Osteomyelitic foci, 161 Ovariotomy, 53-54, 179 "Painting," anaesthesia by, 96-97 Palate, operations on the, 135-36 Palatine nerves, infiltration, 130, 135 Palniaris longus, M., 166 Palpebral reflex, 125 Panophthalmitis, suppurative, 127 Paracentesis, 116 Paraflin, 79 Paralysis of accommodation, 29 Paranephrin, 42 Paraphimosis, 197 Parenchymatous injections, 48 Parietal peritoneum, sensibility of, 176, 179, 184 Parke -Davis, preparations by, 42 Parulis, incision of a, 99, 141, 146, 170 Patellse, bursa, operations, 171 Pelikan, method, 6 Pellacini, investigations of, 42 Penis, operations on the, 195-97 Percival, method, 6 Perichondrium, 103-4 Perineum, ruptured, suture of, 199 Perineural method of injection, 10, 63, 66, 68, 73 Periosteum, infiltration of the, 69, 108-9, 154, 159 ; sensibility, 102-3 , nerves supplying the raaxillffi, 129. 130, 132-35, 137 Peripheral nerves, 64 Peritoneum, incision of the, 182 Perityphlitis, 181 Pernice, method, 10 Petrow, use of suprarenin, 72 Pharynx, anfesthesia of the, 55, 120 Phenol, 55, 84, 87 Phenol-cocain solution, 113-14 Phimosis, operation for, 195 96 Phlegmons, treatment of, 52, 167- 69, 174 Pinna, operations on the, 111-12, 115 Plasters, 5 Plastic operations, 110, 118 Platino-iridium needles, 78 Pleura, puncture of the, 154-55 Plexus, brachial, 158 Plexus, den talis inferior, 137 Poppy, 5 Poultices, 5 Poupart, ligament of, 189, 191 Pressure, anesthesia by, 11 Pressure sensations, 20 Protoplasm, chemical affinity of cocain for, 19 Pterygo-palatine fossa, 129, 131 Pyriform aperture, 137 Quaddelanasthesie, 9, 93-95, 97 Quellungsanasthesie, 14, 15, 59 Quellungschmerz, 15, 19 Radial nerve, 161, 166; anaesthesia of the, 167 "Eadical" operations, 117 Rami alveolares, 129, 130 Rami cutanei ant., 188 Reclus, use of cocain, 8-9, 24 ; method of anaesthesia, 56, 172. 194, 197 "Record" syringe, 77, 122 Rectum, 200 Rectus, 181 Regional anaesthesia, 9-10 Renal parenchvma, sensibility, 176 Resections, 73, 103, 120, 133-34, 154-55, 161 Retrosternal extension, 147 Rhino-laryngology, 29 Ribs, resection, 103, 154-55; carious foci, operation for, 155-56 Richardson, ether spray apparatus, 3, 5, 32-33 Ritter, observations, 176 Roberts, method, 9 Rochet, anaesthesia by ether, 2-3 Roser, operation of, 196 Rossbach, cited, 3 Rubber bands, use of, 162-63, 165, 173-74 Rupprecht method, 114, 120-21 14 210 LOCAL ANESTHESIA Salt solutions, use of, 15-16, 42, 48, 52, 57-60, 70, 77, 79-82 Salves, use of, 125 Saphenous nerve, 87-89 Saphenous vein, extirpation of, 170, 173 Saponin, anaesthesia by, 6 Scalp, anaesthesia, 95, 96, 99, 103 ; operations on the, 105-9 Scapula, resection of, 53-54 Schafer, investigations, 42 Scheff, method, 5 Scheller, cited, 3 Scherzer, use of cocain, 6 Schleich, method of infiltration, 8- 9, 11, 16, 39, 41-42, 56-63, 67, 69, 83-85, 93-94, 97, 99-103, 117, 122, 127, 132, 141-42, 146, 153- 55, 158, 160-61, 170, 172, 177, 179-80, 186, 188, 191-92, 195, 197 ; method of using cocain, 22- 23 ; of alypin, 29 ; and suprare- nal preparations, 50-51 ; method with inflamed areas, 64-65 Schlofi"er, use of alypin, 29 Sclerotic, puncture of the, 128 Scrotum, operations on the, 197-99 Sensory nerves, 58, 61, 93, 95, 97, 102, 111 Septum, 118; resections, 120 Serous surfaces, anaesthesia of, 54-56 Shoulder, operations on the, 157- 58 ; exarticulation of the, by Crile, 158, 174 Simpson method, 6 Skin, anEesthesia of the, 16, 93-95, 199; grafts, removal, 159, 169 Smell, sense of, action of cocain, 20 Soakage anaesthesia, 16 Soda solutions, 77 Sounds, use of, 122 Specula, use, 199 Spermatic cord, 191-92, 198-99 Spermaticus externus, nervus, 188 Speyer, cited, 36 Sphincter ani, operations for, 200- 201 Spinal anaesthesia, 27, 67, 73 Splinters, visible, 52 Spray, cocain-suprarenin applied by, 121 Sternocleido-mastoid, 145, 158 Sterno-mastoid, 148 Sternum, anaesthesia of the, 103 ; carious foci, operation for, 155-56 Stolz, preparations by, 44 Stomach, sensibility, 176, 177-78 Stovain, use of, 29 Strabismus operations, 126-27 Stricture, 194 Strumectomies, 145 Strumous glands, 65 Subconjunctival injection, 17, 28, 124, 126-28 Subcutaneous infiltrations, 142-43, 155 Subdeltoid bursae, 158 Subgingival injections, 138, 140-41 Submucous infiltrations, 142, 144 Superiosteal infiltrations, 117, 142, 154, 155 Suction apparatus. Bier, 153 Sulcus bicipitalis internus, 89 Sulcus bicipitalis lateralis, 89 Sulphuric ether, 2-3, 32-33, 35 Suppuration, 168, 171 Suppurative mastitis, 153 Supraclavicularis, 145 Supraorbitalis, nervus, 106, 131 Supra- and infra-trochlearis nervus, 106 Suprarenal gland, 11 Suprarenal preparations, use of, 25 28, 29, 31, 41, 56, 67, 80-82, 87 95, 96, 97, 104, 109, 120, 125 162 ; nature and action of, 42 51 ; preparations by synthesis 44-46, 82-83, 147 ; dosage, 46 47, 49, 82-84, 107-10; dangers associated with use, 50-51 abandoned by Bier, 72 Suprarenin hydrochloride, 43, 45 Suprarenin-poisoning, 48-49 Suprareninum syntheticum, 43-47, 83 Surgical Congress, 1892, 9; 1908, 68 ; 1909, 11, 60 Sutures, 95, 142, 143, 199 Sympathetic, the, 175 Synovial membrane, 104, 171 Syringes, injection, 77-79. 122, 193 Tactile sensations, 20 Takamine, investigations, 42 INDEX 211 Taste, sense of, action of cocain, 20 Teeth extractions, anaesthesia for, 39, 54, 138-43 Temperature, difference of, im- portance, 61 Tendons, 101, 102 Tenotomy, 166, 172 Terminal anaesthesia, 9, 32, 54, 93, 95 Thenar eminence, 166 Thiersch, removal of skin grafts, 159, 169 Thigh, ansesthesia of the, 170-71 Thorax, operations on the, 153-56 Thumb, the, 166 Thymol, 43 Thyroid cartilage, 150 Thyroid gland, removal, 147 Tibia, 172 Tiefenthal, method, 114 Time for completion of ansesthesia, 84, 85, 96 Tissues, inflamed, infiltration, 99 Toe, ansesthesia of the, 5, 40, 66, 174 Toe-nail, ingrowing, 54, 174 Tongue, operations on the, 143-44 Tonsils, extirpation 120-22 Tourniquets : Bier's use of, 69, 71, 72, 86-87, 173-74 effect of application on absorp- tion, 40-41 Esmarch's 12 Oberst's method, 162 Trachea, 149, 151 Tracheotomy, 149 Traction, 76 Trephining operations, 107, 109, 117, 136-37 Trigeminus, 129, 131 Tropacocain, 17, 27-28, 124 Tumours : aseptic cystic, 146 cauterization, 199 cystic, 183 glandular, 170 mammary, 153-54 Tumours : nasal, 118 ovarian, 179 removal^of, 98, 100-4, 110, 118 Tiirck, investigations, 5, 42 Tympanic epithelium, 114 XJlnse capitulum, 167 Ulnar nerve, 161, 164, 165, 166; injection for the, 167 Umbilicus, 186 Urethrotomy, 193-94 Vagina fixations, 199-200 Vagus nerve, 111, 113 Vaso-coustriction, 49, 51 Vaso-dilatation, 51, 124 Veins, risk of injecting into, 85-86, 148; exposure, 87-90; course in the lower extremity, 88-89 ; course in the arms, 89-90 ; ex- tirpation of saphenous, 170 Vena cava inferior, 74 Venous ansesthesia. Bier's method, 12, 20, 41, 67, 69, 132, 157, 166, 169-73; dosage for, 68-73; syringes for, 79 ; technique of Bier's method, 86-92; priority of, 104 Vesical mucosa, 193, 195 Vitreous, prolapse of, 125 Vocal cords, 150 Volar nerve, 162, 164, 165 Vomiting, 125 Wagner, 51 Water, injections, 58, 59 Wheal method of anesthesia. 13-17, 19. 57, 93-95, 97, 99, 112, 141, 148, 151, 163, 181, 186, 188, 190, 191, 199 Whitlows, 52 Woehler, laboratory, 7, 18 Woelfler, 7 Wood, discovery of, 6 Zygomatic process, 129, 134 Zygomat. temporalis nervus, 106 BILLINO AND SON'S, LTD., PRINTERS, OUILUKORD 1 COLUMBIA UNIVERSITY LIBRARY This book is due on the date indicated below, or at the expiration of a definite period after the date of borrowing, as provided by the rules of the Library or by special ar- rangement with the Librarian in charge. DATE BORROWED PATE DUE DATE BORROWED DATE DUE AUG1519E MAR 3 1 1963 ' / cae(2Sft)Mioo / RD84 Schlesinger Local anaesthesia. Soh3 COLUMBIA UNIVERSITY LIBRARIES (hsi.stx) RD 84 Sch3 C.1 Local anesthesia 2002286327 Ouf •<> liZL