COLUMBIA LIBRARIES OFFSITE .11 Al III '.'-II Nf.l SMAIIDAHIJ nr^^o. ^HX64056597 RD131 G792 1918 The nature and treat ! The Nature and Treatment of Wound Shock and Allied Conditions W. B. CANNON, M.D. (Boston) Captain, M. R. C, U. S. Army E. M. C O W E L L Captain, R. A. M. C, S. R. JOHN ERASER, M.D., F.R.C.S., (Edin.) Captain, M. C, R. A. M. C. A. N. HOOPER Captain, R. A. M. C. FRANCE Report No. 2, Special Investigation Committee, Medical Research Committee, (Great Britain) Rcl>riiited from The Journal of the American Medical Association Feb. 23, 191S, Vol. 70. pp. 520-535, and March 2, 1918, Vol. 70. pp. 607-621 Copyright, 1918 American Medical Association Five Hundred and Thirty-Five North Dearborn Street CHICAGO ,RC>\^ .ma?. Columbia ©nitJcr^ftp intI)f(Citpofi^rttigork CoUegf of ^ijpsicians; anb burgeons Hibrarp Digitized by tine Internet Arciiive in 2010 witii funding from Open Knowledge Commons http://www.archive.org/details/naturetreatmentoOOgrea The Nature and Treatment of Wound Shock and Allied Conditions W. B. CANNON, M.D. (Boston) Captain, M. R. C, U. S. Army E. M. C O W E L L Captain, R. A. M. C, S. R. JOHN ERASER, M.D., F.R.C.S., (Edin.) Captain, M. C, R. A. M. C. A. N. HOOPER Captain, R. A. M. C. FRANCE Report No. 2, Special Investigation Committee, Medical Research Committee, (Great Britain) Copyright, 1918 American Medical Association Five Hundred and Thirty-Five North Dearborn Street CHICAGO 2- PREFACE In August, 1917, the Medical Research Committee (Great Britain) appointed a Special Investigation Committee to undertake the coordination of inquiries into surgical shock and allied conditions, with a view to the better correlation of laboratory and clinical observations. The following were asked to serve on this committee: Prof. E. H. StarlinK, M.D., F.R.S. (Chairman). Prof. F. A. Bainbridge, M.D., F.R.C.P. Prof. W. M. Bayliss, D.Sc, F.R.S. Prof. W. B. Cannon, M.D. (Harvard University). Lieut.-Col. T. R. Elliott, M.D., F.R.S., E.A.M.C. John Fraser, M.D., F.R.C.S. (Edin.). Prof. A. N. Richards, Ph.D. (University of Pennsylvania). Prof. C. S. Sherrington, M.D., Sc.D., F.R.S. Col. Cuthbert Wallace, C.M.G., F.R.C.S. H. H. Dale, M.D., F.R.S. (Secretary). The first report on "Intravenous Injections to Replace Blood" was published as a special Bulletin, Nov. 25, 1917. The second, on "Investigation of the Nature and Treatment of Wound Shock and Allied Conditions," which follows, was issued for official use, Dec. 25, 1917, and Sir Walter Fletcher, secretary of the Medical Research Committee, has given his consent to the publication of the papers in The Journal, as has also the military censor. In sending the report, Dr. Cannon writes: "The work was done in a casualty clearing station a few miles from a part of the line where there has been constant fighting for three years with scarcely any change. Only the most serious cases which could not be reasonably moved any farther back were left with us for the town was repeatedly shelled and the station was twice bombed by aero- planes during my stay. London, with its air raids, is a Paradise by comparison." CONTENTS CLINICAL STUDY OF ]UX)OD PRES- SURE IN WOUND CONDITIONS .. 9 Introduction 9 (a) Instruments Employed and Methods of Invcsligation 9 (&) Control Blood Pressure Readings 10 The Blood Pressure as Observed in Vari- ous Wound Conditions 11 (a) Head Wounds 12 1. Scalp Wounds 12 2. Compound Fracture of Skull with Dura Intact . . . . 12 3. Penetrating Wounds of Skull 12 4. Perforating- Wounds of Skull 12 5. The Effect of Anesthesia on the Blood Pressure Read- ings of Head Wounds . . 14 6. Summary 15 (&) Abdominal Wounds 15 (c) Chest Wounds 20 (d) Mtdtiple Wounds and Wounds of Extremities 21 Blood Pressure Readings as Studied Sub- sequent TO Various Intravenous In- fusions 22 {a) Physiologic Sodium Chlorid .. 22 (b) Ringer's Solution and Its Modifica- tions 24 (c) Colloidal Solution 24 {d) Direct Blood Transfusion . . . . 29 (e) Glucose Solution 30 (/) Other Measures . . . ^ . . . . 30 ' {g) Conclusions 30 6 PrESSIRE OnSERVATIONS IN THE FlRST Week of Convalescence as an Aid to Prognosis and Treatment M SOME ALTERATIONS IN DISTRIBU- TION AND CHARACTER OF BLOOD IN SHOCK AND HEMORRHAGE .. .. 32 Introduction 32 The Blood Changes Peculiar to Shock 33 The Blood Changes Peculiar to Hemor- • rhage 39 Postoperative Blood Changes • 40 Blood Changes Obskrvi:d afti;r ^^\RIOus Injections 42 (a) Blood Transfusion 42 {b) Injection of Gum Solution . . . . 42 (c) Hypertonic Saline Injections . . 43 The Value of Blood Examinations for Prognosis 44 (a) The Significance of Continued Con- centration of Pcnphcral Blood 44 (b) The Significance of Progressive Dilution of the Blood . . . . 45 Summary . . 46 ACIDOSIS IN CASES OF SHOCK, HEM- ORRHAGE AND GAS INFECTION .. 47 Introduction 47 The Relation of Acidosis to Blood Pres- sure, Pulse and Respiration . . . . 49 (a) Relation to Blood Pressure . . . . 49 (b) Relation to Pulse 51 (c) Relation to Respiration 52 The Sugar Content of the Blood . . 53 The Effect of Anesthesia and Operation ON Existent Acidosis and Low Blood Pressure ' . . 54 7 Alkalini': TRi;Arivii';NT of ICxtricmt: Aci- ' Dosis IN Shock 58 Summary 60 THE INITIATION OF WOUND SHOCK 61 Introduction 61 Physiology of the FjofiTiNG Soldier . . 62 Classification of Wounds with Refer- ence to the Incidence of Wound Shock 63 Class A. Trivial Wounds 63 Class B. Mhderatcly Severe Wounds CA Class C. Scriotcs Wounds 67 Conclusions 70 A CONSIDERATION OF THE NATURE OF WOUND SHOCK 71 Introduction 71 The Bearing of Present Work on Pre- vious Theories of Shock 71 (a) The Acapnia Theory 71 (b) The Idea of Suprarenal Exhaustion 74 (c) The Nerve Exhaustion Theory . . 75 The Cardiac Factor 78 The ProSlem of the "Lost Blood" in Shock 79 In the Arteries? 79 In the Veins r . . 80 1)1 the Capillaries!' 81 The Viscosity, Factor 83 The Effects of Acidosis on the Circu- lation 85 Vicious Circles in Shock 88 Shock as "Exemia" 89 A Concept of the Development of Shock OR EXEMIA . , , . , . . , , 90 8 THE PREVENTIXl' TREATMENT OE WOUND SHOCK 93 Introduction 93 The Prevention and Eaklv Tki:atmi:nt OF Wound Shock . . 94 Modifications of Tkkatmknt in I'aitij-: Conditions 98 Protection Against tih-: Effi^cts of Slr- GiCAL Operation 98 Preoperative Prophylaxis 99 Operative Prophylaxis 100 CLINICAL STUDY OF BLOOD PRESSURE IN WOUND CONDITIONS * JOHN FRASER Captain, M. C, R. A. M. C. AND E. M. COWELL Captain, R. A. M. C, S. R. FRANCE Introduction For a period of over two years we have been reading and recording the blood pressures in a variety of wound conditions. Certain of the observations have been sufficiently interesting to warrant their record- ance. The results may be summarized under various headings : (a) Control blood pressure readings. (b) The blood pressure as observed in wound con- ditions. (c) Blood pressure readings as studied subsequent to various intravenous- infusions. (d) Observations on the blood pressure in the first week of convalescence. The readings published in this paper have been made at a casualty clearing station, except where otherwise stated. A. INSTRUMENTS EMPLOYED AND METHODS OF INVESTIGATION We have employed several forms of mercury manometers, and of these generally the "Riva-Rocci" instrument. Lately we have been using a spring sphygmomanometer. It would appear that the mer- cui*y instruments give the most accurate readings of the systolic pressure, but it is difficult to obtain with them a correspondingly exact reading of the diastolic * Discrepancies between the methods reported in this paper and those reported in later papers are accounted for by the fact that this paper had been completed and presented to the Medical Research Committee before the work which appears in the subsequent papers was begun. 10 prt'ssnrc. The spring instnnneiit, which from a iiio^'haiiical point of view cannot be as accurate as a mercury coUuiin, certainly f^ives a more easily api)re- ciatcd rcachng of the diastolic or minimum jircssurc. A great advantage of the former is its adaptability and small compass, allowing it to be easily carried in the pocket. \\'ith this instrument, many pressure observa- tions on recently wounded men were made in the trenches, and in the advanced dressing stations of field ambulances. In certain cases in which the peri])heral pulse can hardly be appreciated, it is necessary to read the pressure by means of the stethoscope. Such read- ings are very accurate, and a result can be obtained when no pulse can be felt.^ Readings have been made of the systolic or maximum ])rcssure, of the diastolic or minimum pressure, and of the pulse pressure. B. CONTROL BLOOD PRESSURE READINGS A very large number of control readings were made from healthy soldiers. As was to be expected, a wide range of results was obtained. The readings of the systolic pressure were slightly lower than the records one would have accepted as normal in civil practice. Over a wide series of cases the average systolic or maximum pressure worked out at fronrl 10 to 120, and the diastolic or minimum pressiire at from 70 to 80, while the pulse pressure averaged 40 mm. Wt made what may be considered an interesting observation, that among soldiers engaged in the actual fighting, more especially infantrymen, the average systolic pressure worked out at a higher figure than among men of the same regiment in support, where they were only exposed to occasional fire. It was noticed that the raised pressure of the fighting man tended to drop quickly when he was resting away from the firing line; for instance, a systolic pressure of 140 mm. dropped to 110 mm., or even to 100 mm. Observations were made on a series of pilots and observers before and after a two hours' aeroplane bombing raid; the a-verage systolic pressure was 135 mm., and it remained constant on return. In only one case the pressure was raised by 10 mm. 1. Latterly wc have used this method to the exclusion of all others. 11 The Blood Pressure as Ojjserved in Various Wound Conditions Pressure readings taken in the line on various tyjjes of wounds,^ at very short intervals after the jjaticnl had been wounded, show two distinct groups: 1. The hypertension group, in which the systolic pressure varies from 150 to 160 or even 170 mm. 2. The hypotension group (with primary shock), in which the pressure varies from 40 to 90 mm. In the number of cases examined at this early period, there were practically none that occupied an intermedi- ate position, that is, showing a normal blood pressure. The pressure of patients in Group 1, after resting and the journey to the casualty clearing station, gradu- ally falls, and in the case of a normal recovery with rest in bed the systolic pressure remains at a steady level between 110 and 120 mm. In Group 2, the patients are cold, often pulseless, and many of them suffer from severe thoracic or abdom- inal wounds. Occasionally the anatomic lesion appears to be entirely out of proportion to the physiologic reac- tion ; for example, a simple bullet wound of the buttock was accompanied by a systolic blood pressure of 50 mm. at the end of the three hours. In this group intense primary shock is present, and with the occurrence of hemorrhage, secondary shock develops and the pressure continues to fall. Following the application of treatment, arrest of hemorrhage and pain, with rest and warmth, the blood pressure may become partially reestablished. A. HEAD WOUNDS 1. Scalp Wounds. — These showed a slight elevation in blood pressure readings ; all the cases which we had an opportunity of examining varied between 120 and 130 in systolic pressure, with a mean diastolic pressure of 100. 2. As the result of further observations made in the front line trenches, the pressures of early wounded are divided into three groups (Cowell, E. M.: The Initiation of Wound Shock, p. 61): (a) Trivial wounds, in which there is no alteration in pressure or tension. (6) Moderately severe and not immediately endangering life, in which there is no primary shock, but in certain circumstances secondary shock develops, (c) Severe wounds, in which unavoidable primary shock is present. 12 2. Compotmd Fracture of Skull icith Dura Intact. — These cases showed a high systolic pressure ; with one exception all the cases that we had an opportunity of examining registered a systolic pressure of 140 mm. and over. The single exception showed a systolic pressure of 100 mm., but such a low reading could be explained by the fact that associated with a ver>' extensive fracture of the bone there was profuse hemorrhage from the meningeal and scalp vessels. 3. Penetrating Wounds of Skull. That Is, Compound Fracture, Dura Tom coid Foreign Body Retained. — On ■ «c c J r 1 c p ( p c > c ) ? ° -- — ... 1 1 1 1 1 1 1 1 ( 1 i 1 1 < 1 , . . ,^, - - . .1 . .^ i . Chan 1. — Blood pi ea sui e in scalp wounds examination of these cases it was found that as a rule a low blood pressure was registered. The systolic pressure varied from 60 mm. to 112 mm. over a series of cases. It was interesting to observe that the dias- tolic pressure closely corresponded to the systolic pressure with a correspondingly low pulse pressure. We can offer no explanation of this feature, which was relatively constant throughout this type of case. The wounds were such as not to result in increased intra- cranial pressure. 4. Perforating IVounds of Skull. — In types of per- forating wounds — that is to say, with entrance and exit wounds — the blood pressure readings could be dh'ided into two groujis, oue in which the systolic read- ing was hig'h, varying from 3K) to 170 mm., and a «>eooDd group in M'hich the readings were low, var)'ing frana 100 to 110 mm. This subdi\ision corresponds to a oontain anatomic distribution. The first group of Blood Pressure c fr^LT^rL 1 1 — . " O'f Siu/f uiil^ dura infpct case numLer : — 'SO no WD c c ) C 5 • M \ t k ' i ) -5^ Spec/a/ Case uirfh profuse JicerrtorrhcDC r.* i - . irs.^e rV^rrr^c: ' 5^^li<: Sijsfol'C rrt:~^rz Q DiasTolic Pressure ^ Chart 2. — Blood press-are i:: coicpound fracture with dnra intact. pressure readings consisted of those in which the liajongia-and-through wounds involre the xentricles, aaad •were accconpanied by hemorrhage into the ca^-ities of tibe ventricle? . 14 In the second i^idnp the wounds had involved the hrain more or less su] )erl"Kially, and jrcnerally occurred in varyiu}^ axes of the frontal and tK'cipital regiojis. Daily readings in i)atients recoverinij after operation for the second type of wound show that the systolic j)ressure is maintained at a constant level of from 110 to 120 mm. as long as convalescence is uncomplicated. The onset of meningitis is accomj^anied by a rise of blood pressure corresponding to the increase in the intracranial tension. 6 loo J prendre Pcnctratng H^our,J, of SkJI Cj:c Numbers 1 ? 3 4- S C 7 ' i //O 100 f J \ BO 70 _. ^ . <; ) C j) i 1 i » • < • 9 I S^itoliC prCiSurt O DiaitoliC prtSi^'c % Chart 3. — Blood pressure in penetrating wounds of skull. 5. The Effect of Anesthesia on the Blood Pressure Readings of Head Wounds. — It was in regard to answering this cjuestion that our attention was first directed to blood pressure readings in various wound conditions. We had noticed a sequence of events somewhat as follows : A man is admitted with one of the severe types of head wounds associated with tearing of the meninges and lacera- tion of the brain; no examination is made of the blood pres- sure; operation is performed within an hour or two following 15 ••ulmission. Tn tlic later staKcs of the operation and suIjsc- (|uently, a case, wliicli before f)[)cration had appeared promis- ing, now entirely alters, the pulse rate becomes very rapid, unconsciousness deepens, the respiration rate is greatly increased, the patient becomes bathed in the most profuse perspiration, the temperature usually falls to a subnormal level, and death very rapidly supervenes. It was difficult to discover any explanation of such a rapid change. The time was too short for sepsis to be the explanation, the amount of hcmorrhaf:(c was never sufiicicnt to explain the condition, and the injury itself was not one that involved any immediately vital BhcJ P„,fc,of„<,, r,c^^J, ef SI../I ' 1 Ca,. f^^b.,. i',^r,:,,>,,.„ti'^,ol..J r tip T"? ' Q / \ V 6-<5' 1 s^,nji< p.^ss^.t o Chart 4. — Blood pressure in perforating wounds of skull. part.'^ We began examining the blood pressures in these cases, and from such an examination we believed we had found the explanation of the disaster. These are cases with a blood pressure which is either low or unstable. If operation is performed during the early stages of the case, the effect of the anesthetic, together with the extensive opening of the skull, is such as to produce a very marked fall of pressure. The level is so low that no further rise is secured, and the patient succumbs to a condition that clinically resem- bles acute shock. 3. Observations published in a later number of this series (Cannon, W. B. : Acidosis in Cases of Shock, Hemorrhage and Gas Infection, p. 47) show that this condition was probably related to a developing ncidnsis. 16 As ail example of tlie uiistalilo lyiK' of blood ])rcs- surc, we have seen a ease in which the systohc hlood l)r^•^sll^c before operation re<,Mstere(l 1()4 nun.; taken innneihately after oi)eration the i)ressure had fallen lo 10 mm. Death followed within thirty minules. With a view lo overcoming the dan.- blood Injury to pancreas and spleen; about IV2 pints of free blood Simple perforation of colon; no free blood Perforated spleen, bruise.! kidney and colon; about 1 pint of free blood Six perforations; small intestine; profuse hem- orrhage Lacerated liver and kid- ney; about 2 pints of free* blood Bruising stomach; no hemorrhage Tear of colon and small intestine Observed in A.D.S. ; ex- act wound unknown: long carry over the open Observed in A.D.S. ; prob- able small intestine lesion Observed in A.D.S.; prob- able small intestine lesion Blood Pressure 90 dias 120 sys. 100 sys. 70 dias. 85 sys 60 dias. 70 sys. 40 dias. 128 sy« 100 dias. 130 sys. 100 dias. 50 sys. ? dias. 150 sys. lUU dias. 100 sys. 80 dias. 110 8ys. 90 dias. 125 sys. 100 dias. 140 sy.s. 100 dias. 138 sys. 100 dias. 140 sys. 95 dias. 138 sys. 100 dias. 140 sys. 100 dias. 130 sys. 90 dias. 105 sys. 70 dias. 90 sys. 60 dias. 130 sys. 90 dias. 140 sys. 100 dias. 120 sys. 95 dias. 120 sys. 93 dias. 125 90 sys. dias. 110 sys. 80 dias. 136 sys. 105 dias. 50 sys. 20 dias. 110 sys. 85 dias. 120 sys. 90 dias. 120 sys. 90 dias. 50 sys. 30 dias. 45 sys. ? dias. 125 sys. 80 dias. 19 3. At a period later than ten liours, the pressure hegiiis to fall and a shocklike condition Ijecomcs evi- denced; the change is due to sepsis and to loss of blood (secondary wound shock). 4. Perforating wounds of solid viscera of moderate severity appear to be associated with a relatively high blood pressure: wounds of the liver and kidney often exhibit a systolic reading of from 130 to 140 mm., and this even in cases in which the hemorrhage is consid- erable. We have observed a tear of the liver in the case of a soldier run over by a limber, in which the systolic pressure of 140 was ^naintained for twenty- four hours. At the end of this time the pressure fell suddenly and the patient succumbed. 5. Perforating wounds of the viscera which do not . open into the peritoneal cavity are associated with a practically normal blood pressure, as in Case 1, an extraperitoneal wound of the colon, and Case 11, an extraperitoneal wound of the rectum. 6. Large wounds of the parietes are generally associ- ated with a lower blood pressure than small wounds, even though the former may have produced much less visceral destruction than the latter. This is probably explained by the fact that in the former instance peri- toneal blood readily escapes, while in the latter the hemorrhage continues to be retained. We have made several observations regarding the effect on the blood pressure of opening the peritoneal cavity. Briefly, we found that if the abdominal cavity contained a large amount of blood, there was a very rapid fall of pressure as soon as the peritoneal cavity was opened, and the blood allowed to escape. If, on the other hand, the abdominal cavity did not contain much blood, the opening of the abdomen was followed by a temporary rise in blood pressure by as much as 20 mm. After ten minutes the blood pressure fell to slightly below the figure that it registered before operation. C. CHEST WOUNDS. A summary of chest cases is given in Table 2. From these readings there are a few conclusions that may be drawn : 1. Large open wounds of the chest with free entrance and exit of air are accompanied by a profound fall of blood pressure ; this is evidenced in Case 9. 20 2. Patients with niiconiplicatod closed wounds of the chest who arrive at the casuaUy cleariiij; station well cared for show normal pressure. 3. When severe internal heniorrha. Severe hemorrhage 138—100 Simple Flesh Wounds- -'3 Flesh wound — arm Flesh wound — leg Flesh wound — arm Multiple Wounds — 140 100 ?A 170 100 :?=; 138 90 26 Multiple wounds — legs. . Slight hemorrhage 110— 90 ■s/ Multiple wounds Slight hemorrhage 128— lOS 2S Multiple wounds Slight hemorrhage 118— 98 29 Multiple wounds Slight hemorrhage 100— 75 30 Multiple wounds Slight hemorrhage 100— 80 1. Compound fracture of the lower extremity, seen' in the casualty clearing station, was generally associated with a considerable fall in blood pressure, more marked when the fracture affected the region of the knee joint. Undoubtedly the blood pressure read- 22 ing was largely aftcctcd by the amount of hemorrhage that had occurred. One finds in such a case as Case 6 — a severe compound fracture of the tibia with a very small amount of hemorrhage — a systolic blood pressure registered of 143. On the other hand, Case -i — a com- ]iound fracture in the neighborhood of the knee, accompanied by severe hemorrhage — registered a sys- tolic blood pressure of only 30. 2. One might expect compourid fracture of the upper extremity to affect the blood pressure less than fracture of the lower extremity. We were surprised to tind the comparatively low pressure which compound arm fractures generally registered ; the remarks that are made as regards hemorrhage in wounds of the lower extremity equally apply in this connection. 3. In face wounds there is not much alteration of the blood pressure, unless there is an associated con.pound fracture of the face bones, when the pressure is gen- erally lowered. 4. Multiple wounds of the body and extremities were accompanied by a considerable fall in blood pressure. Blood Pressure Readings as Studied Subse- • QUENT TO Various Intravenous Transfusions a. physiologic sodium ciilorid For many years the intravenous infusion of physio- logic sodium chlorid solutions (0.9 per cent, sodium chlorid) has been extensively used in shock and in col- lapse after hemorrhage. We confess we have been greatly disappointed with the results obtained, and blood pressure readings confirm the clinical disappoint- ments that we have experienced. Chart 5 is typical of many that we have recorded. Private C. M. was admitted with a simple fracture of the right humerus and a severe shell wound, involving the right knee. The wound was sustained at 9 p. m., and he was admitted to the advanced dressing station by 10 p. m. He was then in a collapsed and pulseless condition. He was treated by. the application of warmth, and half a pint of physiologic sodium chlorid solution was given subcutaneously in each flank. By 1 a. m., that is, three hours after admission to the advanced dressing station, his condition was said to have so 23 far improved as to warrant liis removal to tlic casualty clear- ing station. On admission to the casualty clearing station he was found to be extremely collapsed; a radial pulse coidd only occasionally he felt; the systolic hlood pressure harely registered 30 mm. of mercury; no diastolic pressure was read. Two pints of physiologic sodium chlorid solution were administered intravenously; immediately the systolic pressure rose to 75 mm., Iiut after a period of about twenty minutes it Sy;. folic 9/cci/ Pressure ° c r s 11 7 1 *^ ■ I ^ g .^ ? <;, ". -^ •<»• \ Ptc. CM. 70 1 \ / 1 1 60 50 -io 30 1 / / I 1 a 1 t '5 1 '^'* I h I, V ^20 r' .X \^^ X. J Chart 5. — Systolic blood pressure with administration of physiologic sodium chlorid solution. pints of rapidly began to fall, and within one hour after the adminis- tration it had fallen actually to a lower level than before the infusion had been given. There was no further rally, and ^eath occurred about three hours later. The blood pressure (systolic) readings are graph- ically recorded in Chart 5. It would appear that the introduction of the physi- ologic sodium chlorid solution induced a condition of 24 liydrtiuic plotliora — tb.at is. a ililiuion and increase in the total volnnie of tlie blood. The kiilneys, the skin and the lymph channels excrete the excess of fluid, there is profuse perspiration, and presently the blood is actually less in bulk and more concentrated than it was before. This is in kecpinjj with the observations of Lazarus Barlow, who has shown that the specific j^^ravity of the blood at first falls from \.0(A to 1.054, anil later rises to 1.067; in other words, there is at lirst a dilutit)n of ihc lilood and afterward an actual con- centration. n. ringer's solution and its modifications The fluid known as Ringer's solution has the follow- ing composition : sodium chlorid, 0.9 per cent. ; potassium, 0.0.^ j^er cent. ; calcium, 0.02 per cent., and a trace of sodium carbonate. In place of this we have been using a hypertonic solution, as recommended in a ])ul)lication of the Med- ical Research Committee, and constituted thus: sodium chlorid, 2 gm. ; potassium chlorid, 0.05 gm.; calciuui ihlorid, 0.05 gm. ; water, 100 c.c. From its intravenous use we have obtained satisfac- tory results, and the clinical history and blood pressure chart of a typical and successful case is recorded. Sergeant A., R. F. A., was admitted with a severe shell wound of tlie pelvis, injury to the I)ladder and prostate and profuse bleeding. On admission the respective pressures were: systolic, 90 mm.; diastolic, 60 mm. Immediate opera- tion was necessary. Subsequently there was intense col- lapse — the systolic pressure registered only 25 mm., the diastolic pressure about 20 mm. Two pints of hypertonic solution were administered intravenously, and in immediate response the pressures rose, respectively, to 1(X) mm. and 80 mm. One hour later they had fallen to 65 mm. and 50 mm. Thereafter the pressure steadily began to rise, and six hours later it had reached 100 mm. and 80 mm. The readings were maintained, and an eventual recovery was made. Chart 6 graphically illustrates the blood pressure (systolic) readings in this case. c. colloidal solution At the suggestion of Prof. W. Bayliss and Col. Cuth- bert Wallace, A. M. S., we have used intravenously in 25 cases of hy])()tcnsioii due to profound shock and the toxemia of gas gangrene a solution of gum acacia. We had In'st arrived at the formula we have used with undermentioned cases, when the rci}ort of the Medical Research Committee was published, March 24. The, formula we employ is as follows: calcium chlorid (B. P.), 0.075 gm. ; sodium chlorid, 1.325 gm. ; gum acacia, 2 gm. ; water, 100 c.c. A double strength solution is conveniently made and kept in sterilized bottles — sterilization should be repeated each week s.pio/,.- BIoqJ r.mc 1 ^ -', E f E E e E 90 BJ ;-j eo so 10 30 :o \ ! ^-x / / \ 1 s 1 1 1 • 1 1 \ / 1 I*? 1^ < ) ScrytA Chart 6. — Systolic blood pressure with administration of 2 pints of hypertonic solution. This solution is made up as follows : calcium chlorid (B. P.), 13 grains; sodium chlorid, 232 grains; gum acacia, 350 grains ; water, 1 pint. In comparison with the formula recommended by the Medical Research Committee, we give less sodium chlorid and more calcium chlorid, while we omit the potassium salt entirely. With this solution good results have been observed when from 15 to 20 or even 30 ounces of the solution are given intravenously. The 26 solution was fjivcii slowly at the rate of 5 ounces in five minutes, and its heat maintained at a temperature of about 120 F. in the reservoir. It passed from the reservoir through a compte-gouttes chamber and entered the body by means of a small glass cannula tied into cephalic or saphenous veins. The infusion was repeated after twelve or twenty-four hours, if necessary. ^'■y 1 z 3 * f e '00 so 60 SO n^ ,- ^ 1 i 1 1 1 1 1 1 A ) 1 1 Cos 10c, ft -27 1 s h t, .. <, ■^1 Chart 7. — Systolic blood pressure with administralion of an infusion of 30 ounces of gum solution. Chart 7, taken from Case 27, is added to illustrate graphically the blood pressure (systolic) response in a successful case. From a study of the cases quoted above it may be seen that the pressure almost invariably rises within a few minutes of the infusion being begun. This fact often enables the necessary operative treatment to be carried out, even in the worst type of case which pre- sents itself at a casualty .clearing station — such a case, for example, as shows a hypotension pulse with general collapse and associated with shock, hemorrhage and toxemia. II II I §ISI ^r^ I3I§II ISII^II r^i-ilisii^^i I iHiH i-lrH iHrHI rHlflJ P ssi^s^i|-as3isi| igg> tHHi-lrHlrHi-l t-l QiH iH fHW i-HOJi-lrH QJ g?;;3gg!^^8Sg2ggSSS8SgS8S8Sag g2g8f58;g |88S ^i-HrH tHiH(-l rHrH?-Hi-lr-i r-i i-Hi-Hr-lrHrHrH iH r-t I !g§gs8i^gsgs§assas888gsss ss^sssssss + + +S I +. I + I t I I ++ I ++ I + + + + I + + + + + + + +^ ' 1 + + + + I + ++++++ 1 ++++ 1 !++!++! I ++++ +^:}:+++|+++ 1 ++++^1 I++++I I++I j+i I++++ +1^++++++++ 3 d 3 3 P aaaaa OJ O) OJ O) OJ 4-i t-l <^-) ^W NH q-m-(qH =+H qn O O O O O 0) O ® OJ (D t-t f-i M M ^ 3 3 3 3 3- 4J +J +j +j +:> O O O " C3 C3 Oj 03 CS C3 ctf •5 P- • o o c3 d 'O Td ^3 'O 'O d 3 a a d 33333 00000 aaaaa 00000 OOQOO •O *M a_, >(-n4-| « .5? ° O O O d 5 £_ o H te'0'3'd'0'3'a Masddao^dScdSo— g,oSoooT3>o-oo-o£ ^atjaaag^a^ss^ar «Oa3oooP«0"':OO^Oa! S 2 ^ 0,Q -a -3 a rt 3 < god " 3 000 H5 a: a; 32 00 odd 1) CJ o 3.525 " 5 otH - 3 O-M " Mu_ g'o-::_ M a o'g gx:^ ^ 3 ^ d 5J to S d — 2^-oo • -o S '^ ■ dt;.. P'w r^C^C<5"«i^LO:Ot:*0005C>1-^WOO'<:*^lftcO^-OOOaQ iHt-lHrH?-ti-iOOTH la CO t' 00 C& O r-t 03 C6 '^ lO C<1 G^ S IS 3 11 ISSN II III 6% S 1- -- 1 1 1 1-4 r^ S8 00 1 !§ B 1^ 1 II II III o CB a £ a r- 1 §8 828 Iglll II 111 a Is t4 o 3 a s 2 i's if CO 3 O a [a o a Ic E.£a ■5 w § D CO CO s B s 1 Pi CO 3 -^ as 4) a 3 « > o ..S a B - xio o ■5 > " s 1 ?! a M c c B tr O 1- o :: iBi: (4 1 _ a o ^isg^.gSB^i 1. in W ca t in t. tr - c X! ft-- cT ^f oonSlSgg.,„"B| <; 35^ Wi-D Ox^Kx K^O <-< 1 M : : : 0) " :«*::: o a; ~ "S ■" J3 a • • £:£i o i To |5i = = =.. O c 1 ■5 o S p o ^ s s K — — i; « 3 1 Q j< 3 -S^-^ I. uxi "-i; .o tt o a o B 5 S kO xSPh fifixxSS xd Sx < 3 5 '^ 0*00 -• PU »« t>a >« « ;: o lec ■« Ul 1 1 29 When it has been ])ossib]e to remove the source of infection, tlie rise of pressure is ])roj:(rcssive in the sub- sequent twenty-four iiours, riiul the jjressurc is main- tained during the early critical days of convalescence. In Case 27 the patient was admitted apparently morihund. After an hour's rest with warmtli and rectal glucose-saline injection, he was submitted to laparotomy; there were about 2 pints of free blood in the peritoneal cavity, and six perfora- tions of the intestine required suture. Intravenous infusion BicoJ \ Prf»u'^ / / IZO I / ^Y V no (^ ; r y \ \ 1 t V 100 - -} -! 1 — - - — — - 90 - ^1 — — - - — - — eo «jl 70 ^1 €0 e{ so - — — — - — — — 40 — — - - - — — 30 :; ~^ 1 20 o Chart 8. — Systolic blood pressure with fifteen minutes of direct blood transfusion. of gum was commenced with the operation. When the opera- tion was completed, thirty minutes later, the pressure had risen to 80 mm., and a fair pulse was palpable at the wrist. The following day the pressure was 120 mm. ; it rose later to 140 mm., and remained at this figure during an uneventful convalescence. D. DIRECT BLOOD TRANSFUSION" We have had an opportunity of observing in several cases the results of direct blood transfusion. The 30 transfusion was necessary on account of severe arterial hcniorrhaj;e, and was carried out by the direct nietliod. as suggested by Basset and Fullerton. The time of the transfusion varied from fifteen to twenty-two minutes. It is (hfficult to estimate with any degree of exactness how much blood was transferred during these respec- tive jx'riotls, but we calculate roughly that from 500 to 700 c.c. would be about the proper estimate. The following are the notes and the blood pressure chart of one of these cases: Liculenant , admitted with a severe shell wound of the kfl tliiyh : tlie femoral vessels were lorn; no touniitiuct had heen applied, and the patient was practically murihund from loss of blood. After the local 'wound had lieen dealt with a donor was secured, and direct transfusion of blood begun. Transfusion was continued for fifteen minutes. Clinically there was a most dramatic imjjrovement, and within the course of a few hours the pulse rate had fallen from 150 to 95. The systolic blood pressure on admission was very diflicult to estimate ; but it was estimated at about 20 mm. Before the transfusion had been completed it rose to 115; one hour later it had fallen to 100. At the end of another hour it had risen to 110, and about this level it remained for the first twenty-four hours; thereafter it attained and remained at a level of about 120. The blood ])rcssure readings were as shown on cliarts. E. GLUCOSE SOLUTION We have no records of blood pressure readings fol- lowing the infusion of hypertonic glucose solutions. F. OTHER MEASURES From time to time various drugs are advocated, such as pituitary solution, epinephrin, cafTein, camphor, etc. /\t present there is not sufficient evidence to show that one of these drugs takes precedence over the others. G. CONCLUSIONS 1. In cases of profound shock accompanied by loss of blood, excellent results are obtained from direct blood transfusion. 2. Injection of the calcium hyjiertonic gum solution will produce an immediate rise of pressure in hemor- rhage cases or cases of hypotension, complicated by toxemia. 31 This rise may tide ihc patient throiij:(li an operation. If the source of the infccli(jn is rcniovefl, the tension will remain supported. 3. In milder cases of shock and hemorrhage, infu- sion with hypertonic saline is useful. 4. Results obtained after infusion with physiologic sodium chlorid solution have been unsatisfactory. Pressure Observations in the First Week OF Convalescence as an Aid to Prog- nosis AND to Treatment An extensive niwnber of pressure charts have been collected, showing the behavior of the tension not only before and during operation, but also in the first week of convalescence. We have thus a series of controls that show such complications as the onset of sepsis or gas gangrene, and illustrate the subsequent history of intravenous infusion for shock, hemorrhage and tox- emia. An uncomplicated wound running a favorable course shows a steadily maintained blood pressure. With the onset of gas gangrene or sepsis there is a sudden fall in pressure (Case 13). Occasionally a long sustained hypotension pressure reading may be observed (Cases 9 and 12), even though the patient is quite well and no sepsis is present. A steadily rising or maintained high pressure read- ing, even in a severe wound, may be taken as a most favorable prognostic sign (Cases 2 and 6). We acknowledge our indebtedness to Col. Cuthbert Wallace, C. M. G., A. M. S., and to Professor Bayliss, for repeated suggestions and assistance; to Lieutenant-Colonel Winder, R. A. M. C, and Lieut.-Col. A. H. Safford, R. A. M. C„ for permission to investigate the subject; to Lieut.-Col. T. R. Elliot, R. A. M. C, and the Medical Research Cornmittee for the various instruments which were employed in the investigation. SOME ALTERATIONS IN DISTRIBUTION AND CHARACTER OF BLOOD IN SHOCK AND HEMORRHAGE W. B. CANNON, M.D. (BOSTON) Captain, M. R. C, U. S. Army JOHN FRASER, M.D. Captain, R. A. M. C. AND A. N. HOOPER Captain, R. A. M. C. FRANCE Introduction Tlic importance .of traumatic shock as a serious comiilicating factor of wounds and of sur^^ical opera- tions, and its mysterious nature, have coml)ined to stimulate investigation into its causes and into methods of deahng with it. That investigation of shock has heen (hfficult and baffling is incHcated by the number and variety of the theories put forth to account for it. The (hfiicuUies lie not only in the obscure character of shock itself, but also in complications introduced by attendant conditions, such as hemorrhage and sej)sis. Under these circumstances the most hopeful mode of obtaining insight is by gathering as many facts of observation as possible, with the chance tliat the facts may suggest the nature of the process or processes that are occurring. The observations of Sherrington and Copeman' that intraperitoneal operations on animals raise the specific gravity of the blood, the confirmatory studies of Cob- bett- and also of Vale,^ indicating a concentration of the blood in conditions that induce shock, and the experiments of Mann,' showing that the amount of blood stagnant in the tissues of an animal in shock may be more than 50 per cent, above the amount in the normal animal — all these evidences indicate that 1. Slu-rrington and Copeman: Jour. Physiol., 1893, 14, 83. 2. Colibett: Shock, in Allbutt: System of Medicine, London, 1897, 3. 3. Vale: Med. Rcc., New York, 1904, 46, 325. 4. Mann: Surg., C.yncc. and Obst.. 1915, 65, 380. 33 examination of the Ijlood might yield significant facts. Warfare provides shock cases in hirgc numhers. At a casualty clearing station, where only the most severely wounded were admitted for treatment, wc have had an unusually favorahle opportunity to study their con- ditions, and at Col. Cuthbert Wallace's suggestion we undertook observations on the physical features of the l,)lood in these cases. The present account is based on records of observation in ninety-eight cases of shock and hemorrhage, and in fourteen control cases. The routine examination consisted of a count of the red blood corpuscles (referred to henceforth as "red count"), estimation of the hemoglobin by use of the Haldane hemoglobinometer, and determination of the percentage of cori)uscles in the blood, either by capil- lary hematocrit or by larger graduated tubes, if the amount of blood permitted. When desirable to keep the blood for some time unclotted, potassium oxalate crystals were added in minimal amount; but when this was done, the hematocrit readings were made at once in order to avoid any change of corpuscle volume through the action of the added salt. Although the blood examinations were made in a routine manner, we have kept in mind certain ques- tions to which we hoped to find more or less definite answers : 1. Are these changes in certain physical features of the blood peculiar to cases of shock and of hemor- rhage ? 2. Are there typical postoperative blood changes in these cases ? 3. What are the effects on the blood of intravenous infusions? 4. May the data provided by blood examinations be helpful in prognosis? We propose to present and consider our results under these headings. The Blood Changes Peculiar to Shock In discussing the blood changes in shock it will be desirable to distinguish between cases of severe or extreme shock, as seen at the casualty clearing station, and those of moderate character. To some extent the 34 judgment of these coiulitions is based on an extensive clinical experience of one of us (J. F.) in connection with blood pressure tletcnninations in shock cases.' Combined with this clinical judgment were pressure readings. Roughly, the moderate cases had a systolic pressure over 90 mm. of mercury, and the severe cases not over 70 mm. The first noteworthy characteristic of the blood in shock is a high capillary red count. In Chart 1 is presented the red count in twenty-seven cases classilicd as severe traumatic shock. In all but eleven of the cases the count was 6 million corpuscles or higher, and in ei?ht cases it was more than 7 million cor- Chart 1. — Red corpuscle counts in twenty-seven cases of severe shock. puscles." When hemorrhage as a complicating factor tending to reduce the blood count is considered, these high counts are striking. They indicate that in shock a concentration of the blood occurs, at least in the superficial capillaries. Whether or not the concentration found in capillary blood is true of all the blood can be determined by counting capillary and venous samples taken at the same time. When this is done, a more or less marked discrepancy between the two is revealed. The capillary samples have been taken from widely separated parts of the body — from the lobe of an ear, from a finger or from a toe ; the venous samples from an arm vein. In Chart 2 are plotted the observations in seven cases 5. Frascr, John, and Cowell, E. M.: Clinical Study of Blood Pressure in Wound Conditions, p. 9. 6. These counts were made by means of a Thoma instrument made by Hawksley; it was compared with a Thoma-Zeiss instrument, and a difference of only 10,000 corpuscles in 5,000,000 was found. 35 of severe shock, four cases of moderate shock, and five cases in which no shock was present. The strikingly higher capilkiry than venons red count in the severe cases, amounting frequently tc; 2 million corpuscles, was reduced in the moderate cases, but even in these the dilTcrence is still nearly a million corpuscles per cubic millimeter.'' In the final group of cases, in which no shock was present, the cajjillary count was uniformly slightly higher than the venous, but as compared with the results in the other two groups, the difference is neglible. These observations have been made independently by two observers. Corpusc'ei Millions Severe ShocU 1 2 3 4 S 6 7 MoJ,!,dte ShocU 8 9 10 II No ShocU 12 13 /♦ IS 16 8 7 6 S 4 \ / \fioDi7/arLf Count' / V o A 1 ^ 1 ^ ^=*^^.o-<^ Venous Coun-f ^^^^ ^ Chart 2. — Comparison of red counts, capillary and venous, in cases of severe and moderate shock, and in patients without shock. Biirker^ states that in the same person blood from the finger tip and ear is the same wdth reference to hemoglobin content and red counts within an error of 1 per cent., and that blood from an elbow vein, when flowing free, is indistinguishable from that of the ear or finger. Control observations made by us on normal individuals did not reveal greater differences than 3 per cent, between capillary and venous counts ; and comparative counts of capillary and venous blood taken before rising from bed in the morning proved that the discrepancy is not due merely to inactivity. 7. Capt. E. Emerys-Roberts has reported to us verbally that he has made similar observations in cases of shock, and recently the results have been confirmed by Capt. Eric Taylor. 8. Burker: Tigerstedt's Handbuch der Physiologischen Methodik, Leipzig, 1912, 3, Part 5, p. 4. 36 I'roiii the forcgoiiii:^ consiilcrations it is clear that the (htVerence between cai)illary and venous rcil counts varies roughly with the ilegree of shock, and, since the venous count is approximately normal, the difi'er- ence is due to concentration of the blood or stagnation of corpuscles in the capillaries. In all ])robability the low temperature typical of patients in shock is an important factor in producing the increased corjjuscular content of the ca])illaries. It is known that blood drawn from a cold finger con- tains a larger number of corpuscles in a given volimie than that drawn from the same linger after it has been warmed." In cases of shock, simultaneous counts of venous blood and sami)les from capillaries of the ear, the finger, and the mucous membrane of the mouth show signilicant diflerences. In one case of slight shock the venous red count was 5,360,000, the ear ami linger capillary counts 6,450,000 and 6,280,000, respec- tively, and the buccal count 5,600,000. The capillaries of the mouth, less exposed to loss of heat than those of the skin, contained blood nearer the venous blood in concentration than did those of .the skin, but stil! indicating stasis. When the capillary stagnation has become estab- lished, it does not promptly disappear. We have seen a patient who had recovered from severe shock, but whose hands from wrist to finger tips, in spite of being warmed, were still bluish-gray with stagnant blood. Hematocrit determinations of the volume per cent, of corpuscles in capillary and venous blood have also been made. In each instance duplicate tests were carried out in order to avoid any error that might aris(; from adhesion of blood to the wall of the capillary tube. The results confirmed the discrepancy between capillary and venous sam])les that was found in the counts. The capillary corpuscle volume was greater than the venous by amounts ranging from 12 to 33 per cent. The difference between capillary and venous blood in shock was further confirmed by hemoglobin deter- minations. In cases thus compared, the capillary hemoglobin readings exceeded the venous by amounts ranging from 6 to 29 per cent. In the case cited at 9. Gulland and Goodall: The Blood, London, 1914, p. 61. 37 the end of the second j)ui"igrai)h a1)Ovc, the hcmo^1ol)in reading of the blood in the still abnormal fmgers was 114 per cent., that of llic recovered capillaries of the ear, 104 per cent. A comparison of sonic of the lilood counts and hematocrit and hemoglobin determinations in our cases is ])resentcd in 'J'able 1. As mentioned before, shock is frequently compli- cated by hemorrhage. In these conditions the capillary red count may be low, but when compared with the venous red count the discrepancy between the two at TAT3LR ].— VENOUS AND CAPILLARY RED COUNTS, WITH HEMATOCRIT AND HEMOGLOBIN READINGS, IN SOME CASES OF LOW BLOOD PRESSURE Blood Red Counts Hemato- Hemo- Initials* Pressure (in millions) crit globin Dias- Sys- Venous Capil- Venous Capil- Venous! Capil- tolic tolic lary lary lary P. K. 34 52 3.8 5.6 _ — A. S. 38 62 4.5 6.4 30 41 — — E. G. 40 64 6.2 8.5 30 47 88 113 P. H. (near death) 4.0 6.0 31 43 — — D. H. 48 64 4.2 5.5 37 41 80 95 S. D. 48 72 4.7 5.3 30 35 75 84 W. W. T. t 60 5.3 6.4 — — ■ 92 98 w. C. 58 76 4.5 5.5 — — — — S. F. S. 58 80 4.9 5.3 — — — — T. R. 70 92 5.2 5.6 39 44 107 Ill J. H. C. 80 102 5.8 6.9 41 45 95 105 * Further information about some of these patients may be obtained by finding: these initials in Table 1, Cannon, W. B.: Acidosis in Cases of Shock, Hemorrhage and Gas Infection. t Irregular. once appears. In other words, when hemorrhage com- plicates shock, the blood in the peripheral capillaries contains relatively more corpuscles in a given volume than that in the veins, though in both the number is reduced. Observations from day to day on the capillary blood in cases of shock have shown that there is gradually a drop to normal or below in the count and in the hemoglobin and hematocrit readings. In some instances this return to normal has occurred on the second day ; in others it may not have been completed for three or four days. A fairly typical case of the slower recovery is the following: Case 69 a. — Private L. was admitted suffering from wounds of the face and arm, with fracture of skull ; early gas infec- tion, severe; moderate shock. 38 The red count on admission was 7,510,O(X); the ne^t day it was still hiyh (7,560.000) ; on tiie third day it fell slightly tu 7.280,000, and on the fourth day it was 5,610.000. Counts made on five days during tlic following week disclosed no furtlier important cliangc. The hemoglobin and hematocrit readings likewise fell during the first three days, though not so sharply as the red count. The record is presented in Ciiart 3. The infltiencc of cold in ])roducing .stagualion or concent ration of blood in the capillaries has been men- tioned. It is in the capillary region that the corpuscles are most exposed to contact with the vascular wall, that is, in this region and in the liner arterioles friction Chart 3 (Private L.). — Cuviiit of icd corpuscles, with heniatocril anil hemoglobin readings. is greatest, and the energy stored in the arterial pres- sure is mostly used up. \\'hen arterial pressure is low. as in shock, there is naturally a tendency of the blood corpuscles to gather in the place of greatest resis- tance.'" And if these channels are differentiated by cold, so that some (the warmer) oflFer easier courses, and others (the cooler) more difficult courses for the blood to take, the accumulation of corpuscles, especially in the capillaries of the skin and limbs, may reasonably l)e accounted for as a partial stasis. The blood thus checked in capillary areas would be out of currency, and by failure to return to the heart would contribute to a lowering of arterial pressure. 10. Cohnstcin and Zuntz: Arch. f. d. ges. Physiol., 1888, 42, 326. 39 TiiK TU/)Oi) CirANCES PECur.rAR to TTemorrttage Many wounded men have lost much blood ; they are not suffering from infection, and they appear to have only such elements of the shock complex as the hemor- rhage itself may induce. The question arises as to whether under these circumstances examination of the blood discloses any features that will differentiate hemorrhage from shock. Blood counts of hemorrhage cases show several dis- tinctive features. The capillary red count is usually much lower than that of shock alone, but is by no means as low as the pallid appearance of the patient might lead one to suspect. In twenty-one cases classi- fied chiefly as hemorrhage, the average capillary count at the time of admission or shortly thereafter was about 5,000,000 corpuscles, with variations ranging from 5,800,000 to 3,900,000. In a few of these cases in which the venous blood was also counted", it proved considerably lower than the capillary count. This is what might be expected, for in severe hemorrhage the blood pressure is reduced, and the cooling of the body induces stasis, just as in shock. Another feature of hemorrhage that seems fairly characteristic is a relatively low hemoglobin reading. In the twenty-one cases of hemorrhage, the hemoglobin percentage was 72. If a count of 5,000,000 corpuscles is taken as normal, the color index would be only 0.72, and even with 6,000,000 taken as normal, the index is only 0.9. In shock cases, the index is approximately 1, with 6,000,000 corpuscles regarded as the normal number. The primary reduction in the count and in the hemo- globin percentage in cases of hemorrhage is followed by a further fall. The following instance is illustra- tive: Private G. was admitted with severe wounds of the left leg. Both tibial vessels were severed, and there had been profuse bleeding. There was marked pallor of all cutaneous and mucous surfaces. The blood examinations on admission and on successive days disclosed a fall, and later the begin- ning of recovery. On admission the red count was 5.100,000, the hemoglobin 68 per cent. For the next three daj^s both figures fell ; on the third day the red count was 3.070,000, the hemoglobin 39 per cent. This tendency continued, but at a slower rate, until the sixth day, when the count was 40 1.900,000 and the hemoglobin 35 per cent. From this point a betterment began, and on the eighth day the connt was 2,550.000. the hemoglobin 38 per cent. On the fifth day there were present in tlic blood tilm very small cells resembling microcytes. Throughont the examination no poikilocytosis was observed. We have had several opportunities of coiifirniing, on men who have served as donors in the transfusion of blood, the chauij^cs seen in the foregoing case. In these conditions there could be no question of shock or sepsis. The initial red count of the case illustrated in Chart 4 was 5,600,000, the hemoglobin 102 per cent. Transfusion was performed by the direct method, and it was estimated thai about 700 c.c. of blood passed from the donor. Some hours later the capillary count was still high, 5,700,000, but the hemoglobin reading had fallen to 88 per cent, Tlic changes during the Chart 4. — Ucd count ritul liciiioglobin percentage in a case of lienior- rliagc. next few days are shown in ihc chart. The typical posthemorrhagic fall occurred, but the hemoglobin was relatixely lower than the count. In shock cases with hemorrhage as a noteworthy feature, there is usually a relatively low hemoglobin content of the blood. We may infer from the foregoing evidence that a low hemoglobin reading is highly suggestive of a hcm- orrhaire's having occurred. PosTOPER.vTivi-; Blood Changes Tracing the course of blood changes in shock cases has led to numerous observations being made both before and after operation. In all these cases the operation was performed with warmed ether as the 41 .•iiicsthctic. 'I1ic results of the oljsrrvalions may 1)C thus smnniarizcd : (a) When an operation is associated with consid-^ crahle hlecding, both hcmof^lobin and red count are re(hiced; Init, as in the hemorrhage cases, the hemo- gl()])in falls relatively more than the count. This obser- vation has been conhrmcd in numerous instances. 'J1ie following case is illustrative: Case 18 a. — The patient liad a severe compound fracture of femur. Before admission the hemorrhage had hcen slight; the red count was 5,600,000, hemoglohin 90 per cent. The necessary operation was accompanied hy much bleeding, and the count then was 4,600,000, the hemoglobin 50 per cent. The fall in the hemoglobin percentage in this case was excessive; as a rule it amounted to about 10 per cent. (b) When the operative hemorrhage is slight, the count and hemoglobin reading after operation are com- monly higher than before, and the longer the operation the greater the changes are likely to be. Subjoined is an illustrative case: Case 14 a. — A patient was admitted with a wound of the abdomen through which a portion of the small intestine pro- truded ; the intestine itself was damaged. Hemorrhage had been slight. The red count before operation was 6,400,000, hemoglobin 112 per cent. The operation was completed with a minimum of bleeding; about 1 foot of small intestine was resected. The operation lasted forty-five minutes, and at the end the red count was 8,000,000, the hemoglobin 130 per cent. Perspiration is commonly a prominent feature of these cases during the course of the operation — a con- dition which suggests that the concentration of the blood that we have noted is at least in part due to loss of fluid from the body. That it is not due solely t^a stasis of blood in peripheral capillaries is shown- by observation of venous blood before and after opera- tion. In one instance, in which there was profuse sweating during the operative procedure, the venous hematocrit determinations showed a rise of corpuscle volume from 32 to 40 per cent, in forty-two minutes. A puzzling feature that may be mentioned here is the change observed in the circulating blood when a considerable quantity of blood, previously shed, but retained in one of the body cavities, is removed. The removal is followed by a marked drop in the hemo- globin percentage and in the red count. An explana- 42 tioii of the phenomenon is lackinp;; it has hcen repeat- edly ohscrved. Cask 41 a. — The patient had sustained a penetrating wound of the chest, with much hemorrhage into the left plcur.il cavity. On tlie day of admission the red count was 8.000,000, hemoglobin 80 per cent.; the next day the count was attain 8.000,000. hemoglobin 78 per cent. On the folluwing day 2 pints of fluid blood were aspirated from tlie clicst. Within eighteen liours thereafter the red count had fallen to 5,000,000, and the hemoglobin percentage to 52. Twenty-four hours later the count was 4,500,000, hemoglobin 56 per cent. In some cases operation seems to inchice a fraj^jmcn- tation of the red corpuscles. Blood Changes Observed After Various Injections As means of treating: hemorrhagic and shock, trans- fusion of hlood and injections of solutions of salt and of gum have been widely employed. We have made observations on the blood before and after such treat- ment has been tried. A. blood transfusion From 500 to 700 c.c. of blood have been transfused from donor to recipient, either directly, artery to vein, or by means of the Kimpton tube. No diluting or chemical substance has been added to the blood. Nat- urallv transfusion is done when the blood count is low, and. as is to be expected, a great improvement occur.s in the recipient's condition. The following case illus- trates the degree of improvement that may take place: Case 100 a. — The patient had received severe multiple wounds; one leg had been blown off. The red count before • transfusion was 1,900.000, hemoglobin 31 per cent. It was esti- mated that about 600 c.c. of blood were transfused directly from a donor. Twelve hours later the red count was 3,000,000, hemoglobin 56 per cent. Twenty-four hours later the count was 2,500,000, hemoglobin 60 per cent. Thenceforth there was steady improvement. B. INJECTION OF GUM SOLUTION A 7 per cent, solution of gum acacia in physiologic sodium chlorid solution has been advocated by Bayliss" to raise blood pressure in shock and after hemorrhage. 11. Bayliss: Proc. Roy. Soc, 1916, 89, 380. 43 Wc had occasion to note the (effect of llic injection of this sohition on the blood count: Case 64a. — The patient had sustained a severe abdominal wound, with profound collapse. A pint of 6 per cent, solu- tion of gum acacia was injected intravenously. Before the injection the red count was 4,500,000, hemoglobin 84 per cent. Three hours after the injection tlie count was 3,800,000, and the hemoglobin 78 per cent. The persistence of the dilution of the blood in this case is noteworthy. C. IIVrERTONIC SALINE INJECTIONS The hypertonic solution was made according to the formula : sodium chlorid, 2.0 ; potassium chlorid, 0.05 ; calcium chlorid, 0.05, and water 100. Injection of this fluid produces effects that are illustrated in the cases given. Case 65 a. — The patient had sustained a compound fracture of femur; the limb was almost severed; there was consider- able hemorrhage. In the first blood examination the capillary count was 5,290,000, hemoglobin 84 per cent. ; the venous count 4,700,000, hemoglobin 75 per cent. Immediately after opera- tion a pint of hypertonic salt sc^lution was injected intrave- nously. Five hours later the capillary count was 4,600,000, hemoglobin 70 per cent. Case 60 a. — The patient had a compound fracture of tibia and fibula, with considerable bleeding. There was early gas infection. The patient's appearance was pallid. Shortly after admission the capillary red count was 6.330,000, hemoglobin 102 per cent. ; the venous count was 4,200,000, hemoglobin 94 per cent. After operation 2 pints of hj-pertonic salt solution were injected intravenously. Six hours later the capillary count was 4,120,000, hemoglobin 55 per cent. It is noteworthy in these cases that the capillary red counts, some hours after the injection, were much lower than the original capillary counts, but corre- sponded fairly closely with the original venous counts. This change may be interpreted as a disappearance of the capillary concentration, probably due in part, at least, to improvement in the circulation. The striking feature, however, is the greatly lowered hemoglobin reading when the larger amount of the hypertonic solution was injected. Why this change occurs is difficult to explain. It is a serious disturbance in an important element of the blood, however, and sug- 44 jjcsts that care should he exercised to avoid iiitrochicing unnecessarily large amounts of hypertonic solutions. The \\\lue of Blood Examinations fok PrcT«3N0SIS Only repeated examinations of the hlood are of proii^nostic \alue ; conclusions cannot he drawn from a single ol)Scr\ation. After this conditional statement we would call attention to the two following points : A. TIIK SIGMFICANCF. OF CONTINUED CONCENTRA- TION OF PERIPHERAL BLOOD The concentration of cai)illary hlood, which occurs in shock, if persistent, ai)pears to indicate an unfavor- able prognosis, and an increasing concentration is a significant precursor of a fatal outcome. The inter- relation between the clinical condition and the per- sistence of capillary concentration is illustrated in the following cases : Case 78 a. — The patient was admitted with a bullet wound of the abdomen. Operation disclosed two perforations of the ascending colon. On admission the capillary red count was 8,300,000, hemoglobin 96 per, cent. The blood was examined on each of the following four days : July 13, red count 7,800,000 ; hemoglobin 104 per cent. July 14, red count 6,600,000; hemoglobin 98 per cent. July 15. red count 7,400,000; hemoglobin 98 per cent. July 16, red count 7,100,000; liemoglobin 99 per cent. During this period the clinical condition of the patient was precarious; there was restlessness, persistent thirst, and low blood pressure, with rapid pulse. On the fifth day the capillary blood count suddenly fell to 5,200,000, hemoglobin 82 per cent. ; and on the next day still farther, to 3,700,000, hemoglobin 68 per cent. This change synchronized with a striking improvement in the general clin- ical condition, and an uninterrupted recovery followed. Case 14 a. — The patient was admitted with a gunshot wound of the abdomen, and perforation of the small intestine. The capillary red count was 6,489.000, hemoglobin 112 per cent. At the end of twenty-four hours the concentration had increased, and the count then was 8,700,000, hemoglobin 130 per cent. This case terminated fatally within the next twenty- four hours. Whether the persistent concentration of the capillary hlood is due to a circulation inadequate to establish and maintain a uniform distribution of corpuscles, or 45 is due to sonic chcniical alteration in the corjHisdcs or in the cajjillary wahs, we do not wish at this time to consider. The ohservations recorded in the fore- going cases, however, we have had repeated opportu- nities to verify. H. THE SIGNIFICANCE OF PROGRESSIVE DILUTION OF THE BLOOD As ]>reviously pointed out, the intial concentration of the capillary hlood normally passes away after a few days. The hlood count falls as if the peripheral hlood were being diluted or the stagnant corpuscles being swept away. In association with loss of blood, dilution occurs from increase of plasma, but this process also is short lived. A dilution of the blood which continues to progress beyond the fourth or fifth day after injury is ominous, and the longer the dilution continues the more unfavorable it becomes. In the absence of repeated hemorrhage, progressive dilution signifies the presence of sepsis, and generally the involvement of the blood stream (septicemia). The following case is illustrative: Case 4 a. — The patient was admitted with a severe wound of the buttock and high compound fracture of the femur. The daily blood examinations are recorded in Table 2. TABLE 2.-DAILT EXAMINATIONS IN PROGRESSIVE DILUTION OF BLOOD Day • Capillary Red Count Hemo- globin, per Cent. Day Capillary Red Count Hemo- globin, per Cent. 1 2 3 i 5,400,000 4,500,000 4,500,000 S,90O,00O 85 66 62 61 5 6 7 8 2,500,000 2,300,000 2,200,000 2,000,000 54 56 54 50 The local wounds were irrigated with flavine, and were doing so well that it was difficult to account for the pro- gressive deterioration of the blood. On the eighth day the patient left our care, but we learned afterward that the deteri- oration continued, and eventually the patient succumbed to a septicemia. We have recorded the foregoing case as a single instance of the progressive dilution of the blood, obscure in origin, and follow^ed by septicemia, but we have made several confirmatory observations. 46 Summary In cases of shock as seen at a casualty clearing sta- tion in conditions of warfare, the red count of blood, taken from various capillaries, is hiijher than that of blood taken from a vein. The discrepancy is greater the more profound the shock, and not infrequently is as much as 2,000,000 corpuscles per cubic millimeter. Since the venous count is ai)proximately normal, the condition is due to a stagnation of corpuscles in the capillaries. The observations by means of blood counting have been confirmed by hematocrit and hem()i:;lobin determinations. 'J'his condition once established in shock is only gradually recovered from ; the recovery sometimes requires two or three days. After hemorrhage, and in cases of shock compli- cated with hemorrhage, the hemoglobin reading is rela- tively low compared with the red count. After operation attended by hemorrhage, the hemo- globin reading is again relatively low compared with the count. If the operation has not been accompanied by hemorrhage, the count and the hemoglobin content of the blood may be higher than before, probably owing to loss of fluid from the body. Transfusion of blood naturally raises both the count and the hemogloljin reading. Injection of a gum solu- tion leads to a dilution of the blood that may persist for some hours. Intravenous administration of a large amount (2 pints) of hypertonic salt solution may markedly reduce the hemoglobin content of the blood ; a smaller amount (1 pint) in our experience has not had this effect. Injection of 'the salt solution reduces the capillary stasis. Continued concentration of the capillary blood for several days after injury accompanies a continued unfavorable clinical condition. Disappearance of the concentration is a signal of improvement. Continued tsii.f S^sT^/.a o-y OaiTil.t — H. rc^na„,c^l cf CO, Copot>K i S/cJ k,,,.-. is 50 . 45 <0 35 3J :s :o 15 10 no ,,:o 90 BO SO 40 JO .-J • s 9 COj Cofior.f^ • a:rH'.r Slo^ P-.a^r, ' ' » • » 9 • S c c 5 I ' • • 9 • • 9 _ ••- j) ) \ 5 c > c c • p i <; •1 \^ 5 ~ c p ' 5 J c > * J' i 1 ^ ^ i [ i i i -•- Kecords of blood pressure in tliirty-livc cases of shock, hemorrhage and gas infection, arranged in the order of decreasing carbon dioxid capacity (increasing acidosis). These 6bservations add another to the known sim- ilarities between hemorrhage and shock. In both, the alkaline reserve is lessened. Milroy^ has recently pointed out that hemorrhage, experimentally induced, is attended by reduction of reserve alkali, and that thereupon exposure of the plasma to the same carbon dioxid concentration as before the hemorrhage devel- 8. Milroy: Jour. Physio!., 1917, 51, 272. 51 ops an I T-ioii conccnlr.'ifioii rroisiflcralfly lii<;licr llinii before. In the cases under consideration no observa- tions were made on the 11-ion concentration of the blood. l*rol)ably the concentration was not much raised when the alkaH reserve was only slightly below normal. The activity of the resi)iratory center in some cases, however, indicated a markedly increased concen- tration. These conditions will be dealt with later. From the evidence presented above, the conclusion is warranted that bodily statues characterized by reduced blood pressure and consequently by defective circulation are accompanied by a diminished alkali reserve, and that as a general rule the lower the pressure the lower the reserve. This acidosis should not be compared with that which may occur acutely after a quick run or other sharp exercise. That may be quite as extreme as any change seen in shock, but it is temporary, and the alkaline stores in cells and in other body fluids than the blood may soon compensate for the sudden reduction of available alkali in the blood, and oxidative processes rapidly restore the normal conditions. In the cases under consideration, on the other hand, some process has been going on for hours (often six or eight) that has brought about the state observable at admission of the patient. The progressive character of the process was shown in a case in which the carbon dioxid capacity one hour after the wounding was 50 per cent., and five hours later, with no corrective treatment, had fallen to 40 per cent. The condition has a gradual rather than an acute onset. B. RELATION TO PULSE With low arterial pressure, a rapid pulse may be expected. In the series of cases here reported the heart was seldom beating faster than 144 per minute. Possibly that is a limiting rate for continued action. The average rates were somewhat below this number. Table 3 is arranged on the basis of increasing diastolic pressures. Since the average pulse rates are fairly uniform for different ranges of low blood pressure, and since, as shown above, there is a relation between the lowness of the pressure and acidosis, it follo\vs that there is no definite relation to be found in our cases between 52 the (liniinished alkali reserve ami the rapidity of the heart beat. If tlu- pulse is considered in these cases arraiijjed on the basis of their carbon dioxid caj)acity. the average rate for a carbon dioxid capacity of 24 per cent, is 136; of 35 per cent.. 135, and of 44 per cent.. 130. c. ki:l.\ti(>n to ki:si'iu.\tion The chemical sliniulus increasing respiration is an increase in the 11-ion concentration in the arterial blood. As L. J. Henderson" has slu)\vn. a large auKjunt of acid may be added to a bicarbonate solution similar in concentration to that of the blood before any con- siderable increase of acidity occurs, so long as the carbon dioxid passes off. The H-ions of the blood do not increase to an important degree, therefore, »n TABLE 3.-THE RELATION OP ARTERIAL PRESSURE TO PULSE No. of Cases Average Pressures Pulse Systolic Diastolie Av. Rate Range 5 51 23 133 114-144 9 00 35 134 108-152 13 72 U 133 112-150 8 80 55 133 110-144 7 89 02 128 100-144 spite of reduced alkali, if pulmonary ventilation pre- vents an accumulation of carbonic acid. Only when this process fails, or acids increase to such a degree as seriously to encroach on the neutralizing power of the bases of the blood, does the increased H-ion con- tent aft'ect in a marked degree the respiratory center. From a study of the alkali reserve, by the Van Slyke method, in a large number of surgical cases Caldwell and Cleveland'" report no change of respiration when the carbon dioxid capacity was between 43 and 50 per cent., and also none between 36 and 43 per cent, when that condition was stationary; but if the reserve was diiuiuishiiig and had reached that range, hyperp- nea was almost always apparent. The apparatus necessary to record the volume of respired air in the cases under consideration was not 9. Henderson, L. J.: The Fitness of the Environment, New York, 1913, pp. 149-151. 10. Caldwell and Cleveland: Surg., Gynec. and Obst., 1917, 25, 23. 53 at hand, but the rate of hicathiiit^ was taken. In some of these cases the respiratcjry rate was probaljly reduced to a greater or less degree by morjihin, which was regularly administered to seriously wounrh-d men in amounts varying from '/| to '/. grain, with an occasional larger dosage. In Table 4, the chest cases and the abdominal cases have been omitted, for in them the pain due to respiratory movement may modify the breathing in a way complicating the influence of the blood. As the figures show, the rate increased as the alkali reserve fell, but the change, as was to be expected, became more marked as the limit of the reserve was more nearly approached. The character of the respira- tion was not noteworthy except in the cases of extreme acidosis, that is, with a carbon dioxid capacity in the TABLE 4.— RELATION OF CARBON DIOXID CAPACITY TO RESPIRATION Number of Oases Carbon Dioxid Capacity Average Respira- tory Rate 17 7 6 40 to 49 (av. 44) 30 to 39 (av. 35) 20 to 39 (av. 24) 24 28 44 region of 30 per cent or lower. In some instances the breathing was deep and vigorous, as in true ''air hunger," and at the rate of 40 or 50 times per minute. These conditions have been met especially in cases of infection with the eas bacillus. The Sugar Content of the Blood Lack of food, or subsistence on a carboh3^drate-free diet, as is well known, will produce a condition of acidosis marked by lowered carbon dioxid tension of the alveolar air, increased excretion of ammonia nitro- gen in the urine, and the appearance of acetone bodies. The low blood pressure of shock with attendant slight urinary secretion, and the generally depressed state of the patient, render accurate studies of the urine diffi- cult. The possibility of a "starvation" acidosis being present, however, is suggested by the fact that not infrequently men are brought to the casualty clearing station about noon who have been wounded and 54 shocked in a nij,'ht raid, and who testify to having eaten nothinj; since the previous afternoon, (^n athuis- sion to the station, tliey arc often too ill to take nour- ishment. In conse(|Ucnce they may. be without food for a time which mi{,dit be expected to produce mctalxilic disturbance. A jirimc condition for "star- vation" acidosis is lack of sufficient carbohydrate in the body to play a necessary role in the oxidation of fat, in this instance body fat which is being used as a source of energy. Determinations of blood sugar will show, therefore, whether or not a deficiency of carbo- hydrate ])rc\ails. In Table 5 are presented the results of observations in cases of shock and hemorrhage. From these observations it is clear, in the first jilace. thai there is no lack of sugar in the blond ; indeed, that TABLE 5.-SDGAR CONTENT OF BLOOD IN CASES OF SUOCK AND HKMORRHAOR Carbon Blood Oiirbon Blood iDitinls Dioxid Capacity Sugar iDitinls Dioxid Capacity Sugar F. W. 34 0.11 A. H. P. 47 0.10 W. B. 36 0.1. 'i W. G. 47 0.18 0. C. R. 40 0.15 (6 hours after hit) 0. C. R. 50 0.12 (1 hour after hit) J.B. 42 0.19 A. S. 52 0.11 (after op'n') H. H. 42 0.22 A. S. 60 0.12 (before op'n) the amount is commonly above normal — 0.1 per cent. Furthermore, there appears to be no relation between variations of the carbon dioxid capacity of the blood and the percentage of sugar. In a few cases urine was obtained from shock cases and tested for acetone bodies. The test for diacctic acid was negative. The acidosis of shock cases, according to this evidence, is due to some other alteration of the blood than the development of acetone bodies. The Effect of Anesthesia and Operation on Existent Acidosis and Low Blood Pressure That anesthesia and operation are accompanied by a reduction in the alkali reserve of the blood has been shown by Crile and Menten,^' Austin and Jonas,'" 11. Crile and Menten: Ann. Surg., 1915, 62, 262. 12. Austin and Jonas: Am. Jour. Med. Sc, 1917, 153, 90. 55 Morriss,"' and Caldwell and Cleveland.'" The largest drop during operation recorded by Austin and Jonas was 10 volumes per cent, carbon dioxid capacity, as determined with the Van Slyke apparatus. The figures re[)orted by Caldwell and Cleveland, based on a study of a large series of cases in which they used the Van Slyke method, show a drop in the carbon dioxid capacity between 4.7 and 7.7 volumes per cent, in operations averaging about fifty minutes in duration. In their series, however, no acidosis was present (except in one case), and the drop barely brought the capacity to the boundary line between normality and TABLE 6.— TESTS AFTER OPERATION IN CASES WITH ACIDOSIS AND LOW BLOOD PRESSURE Carbon Dioxid Blood Duration Capacity Pressure luitiala of Operation Before After Before After Operation Operation Operation Operation Mins. % % S. R. 75 58 46 82-58 58-36 B. S. 40 58 46 88-62 74-42 P. A. T. 60 56 40 98-80 64-48 G. J. H. H. 45 50 44 90-62 04-46 W. 0. 20* 49 40 76-58 — J. H. C. 45 47 40 102-80 50-28 W. A. T. 60* 46 38 76-36 68-28 O.K. 50* 46 27 84-60 58-36 0. P. H. 70 41 28 76-46 — Averages 52 50 38 88-62 (7 cases) 62-31 * Anesthetized with nitrous oxid and oxygen. acidosis (50 per cent.) It is well known in civil sur- gical practice that patients with a low alkali reserve (as diabetics with acidosis, and children whose reserve is naturally much lower than that of adults) stand operation poorly, and may pass from anesthesia into coma and die. A highly interesting and practical question, therefore, is raised as to the influence of anesthesia and operation on wounded men with an acidosis already existent. In Table 6 are shown the results of blood tests and blood pressure readings before and after operation in cases with a carbon dioxid capacity below 50 per cent, at the start or found below that level at the end of anesthesia. 13. Morriss, W. H. : The Prophylaxis of Anesthesia Acidosis, The Journal A. M. A., May 12, 1917, p. 1391. 56 Comparison of the clianges in the hlood of these wounded men sulTerinej from shock and unstahle cir- cuhition with those reported hy Caldwell and Cleveland reveals that the average drop in carhon dioxid capacity is approximately twice that seen by them in ordinary civil cases. I'^urthermore, if the three cases are elim- inated which at the start had a carbon dioxid capacity well over 50 per cent., the results show that the fall is likely to be greater the lower the original capacity. The encroachment on the reserve of alkali is greater, therefore, as the margin of 'safety in the reserve is less. In other words, the more marked the existent acidosis the more sensitive is the patient to ojierative procedures, and the more likely he is to be let down by them into a region of danger. In ten of the series of cases under consideration the carbon dioxid capacity before operation was 40 per cent, or less. The close- ness of danger in such cases may be realized by the fact that blood taken from the heart at the moment of death from shock has a capacity between 20 and 24 l)er cent., and in two of the cases re])orted in Table 6 the capacity fell to 27 and 28 per cent, from an initial 46 and 41 per cent., respectively. Such profound changes may occur in about an hour. The suddenness of this remarkable fall in available alkali is in itself important, for as Caldwell and Cleveland have pointed out. the effects are more damaging when the fall is rapid than when it is slow and gradual. With regard for the baneful effect on internal respiration and on other processes of the body due to an impoverishment of the blood in alkali, it is clear that a rational treat- ment of shock should include provision -against the dangers of this sudden depletion. Table 6 brings out another important fact of prac- tical importance — the striking fall of blood pressure as a result of oi)eration in these cases. In experience with patients in whom the decrease of the carbon dioxid capacity, as a result of operation, did not extenn below 50 per cent, (that is, did not develop an acidosis, in the Van Slyke sense), no noteworthy alteration of arterial pressure occurred. In fact, both the systolic and the diastolic pressure may be higher at the end of operation than at the start, and seldom is there a lowering of the mean pressure. On the other hand, if the carbon dioxid capacity falls below 57 50 per cent., or hcinjij 1)clow llial level it sinks still lower as a consequence of opcralion, llie IjUkxI pres- sure may suffer an astonishing decline, in the seven complete records in Tahle 6, the average fall was 88 and 62 to 62 and 36 — the .systolic pres.sure at the end of operation was commcjnly below the diastolic pres- sure at the start. This ominous sinking of the blood pressure has been repeatedly seen during operation in shock cases in which the alkali reserve was not determined ; in all probability the.se cases should be classified with those in the foregoing list. Marshall" has testified that anesthesia with nitrous oxid and oxygen is specially to be recommended in operating on men in shock, because it leaves the ])aticnt in much better condition than do other anes- thetics. Crile and Lower' '^ also have stated that nitrous oxid-oxygen anesthesia is less likely to increase shock than ether. In two patients in the present series, blood examination before and after operation with nitrous-oxid-oxygen as the anesthetic, there was no change whatever in the carbon oxid capacity; it remained at 58 per cent, in the one, and at 48 per cent, in the other during operations lasting forty and twenty-three minutes, respectively. That this anes- thetic does not preclude a fall of blood pressure and an attendant alkali reduction is shown by the three cases in Table 6 distinguished by asterisks — patients anesthetized wdth nitrous oxid and oxygen. The rate of change in the second of these three, however, was less than in any of the others, and the blood pressure was only slightly reduced. The charted results pre- sented by Caldwell and Cleveland sho\v not quite so great a decrease of the carbon dioxid capacity under **gas" and oxygen as under ether, but they conclude that the dififerences under different anesthetics are negligible. The possibility that the patient anesthetized with nitrous oxid and oxygen may sufl:er no apprecia- ble blood change, and also that such changes as have been recorded may be due in part to lack of skill (as in allowing the patient to become cyanosed), gives support to the judgment that it is the anesthetic to be employed when possible in operating in cases of shock. 14. Marshall: Proc. Roy. Soc. Med., 1917, lO, 27. 15. Crile and Lower: Anoci-Association, Philadelphia, 1914, p. 7S. 58 Alkai-ink Treatment of Extreme Acidosis in Shock 'riic (lanr. J.ow j'.rterial ])ressure, liowever, if prolonged, may incapaci- tate the heart, for Markwald and Starlinj^-" have found that when the systolic pressure falls below (SO mm. of mercury, the cardiac contraction begins to weaken. And Patterson'"' has shown that when the H-ion con- centration of the blood increases (by increased car-, bonic acid), the heart relaxes more and more anrl beats less energetically. The low blood pressure and the acidosis of shock, therefore, may in time imjjair tlie efficiency of the organ, though no primary defect be present. The Problem of the ''Lost Blood'' in Shock If the vasomotor center is efficiently at work, and if the heart is capable of assuming any reasonable burden placed on it, .why is there a low arterial pressure m shock? The answer to this question lies in the dimin- ished volume of blood which is in active circulation. Henderson, especially, has laid stress on the necessity of a sufficient supply of blood being delivered to the heart, if arterial pressure is to be kept at its normal level. In the absence of this supply, as, for example, after hemorrhage, the arterial pressure falls to a low level and can be raised only by introducing blood or other viscous fluid into the vessels. A further question now arises, one of the critical questions in the mystery of shock, "Where is the lost blood in the shocked individual?" There are no indi- cations that it is in the heart or lungs ; it must be, there- fore, in systemic arteries or capillaries or veins. IN THE ARTERIES? The absence of, the lost blood from the arteries is sufficiently proved by the facts already discussed, ^^'ith an efficient vasomotor center and a capable heart, an f.dequate amount of blood in the arteries would be accompanied by high arterial pressure. That the pressure is low, as already stated, signifies that the heart is not supplied with enough Mood to fill the arterial system. 29. Markwald and Starling: Jour. Physiol., 1913, 47, 275. 30. Patterson: Proc. Roy. Soc, London, 1915, B, SS, 394. 80 IN Till-: \i:iNS The \ic-\v (.■(iniiiKiiily lu'Kl in llic past has l)ccii that in shock, blood is staj^nant in the lar<;c venous reservoirs of the chest and ah(K)nien, and especially in the capa- cious splanchnic area. "In shock," it is said, "the suf- ferer bleeds into his own abdominal veins." It appears that this view is based largely on evidence from cxj)eri- ments which has been rather uncritically accei)ted. The most certain way to produce shock in a lower ani- mal is by ex])osure and manipulation of the intestine. Under these circumstances the mesenteric veins stand out prominently, ])lood _i,'athers in the intestinal walls, and becomes more concentrated there, and the struc- tures that have been freely handled appear as if inflamed.^' In other words, blood obviously stagnates in abdominal vessels. Such a condition is not seen in natural shock. According to Keith,''- the venous cis- tern, formed by the big veins of the chest and abdomen, has a capacity of 400 or 550 c.c. Mann''-' has found that the amount of blood that can be obtained by bleed- ing and by em])tying the heart of normal animals is 7G per cent., leaving 24 per cent, "in the tissues." When animals are shocked by exposure of the intestine the amount left in the tissue rises to 39 j)er cent., a differ- ence of 15 per cent. If the l)lood mass of a man of 70 kg. is taken as 3,500 c.c, the amount thus "lost" would be 525 c.c. If this blood were in the veins of the abdomen, systemic or splanchnic, their capacity would have to be greatly enlarged, and their distention would be clearly visible. Surgeons of extensive experience at casualty clear- ing stations in the i)resent war, who have ])erformed many hundreds of abdominal ojierations on ])aticnts in all degrees of wound shock, have testilied that on ojjen- ing the abdomen they have not found any i)rimary splanchnic congestion.^' The method employed to produce shock in lower animals, which has repeatedly called attention to the abdomen and its peculiar circu- lation, has given rise to misleading inferences as to what occurs in natural shock brought on l)y wounding other regions than the abdomen. 31. Morrison and Hooker: Am. Jour. Physiol., 1915, 27, 93. Mann: Surg., Cyncc. and Obst., 1915, 65, 380. 32. Keith: Jniir. Anat. and Physiol. , 1908, 62, 1. 33. Mann: .Surg., Cynec. and Ohst., 191S, 55, 380. 34. Statement by Wallace, Frascr and Drummond: Lancet, London, 1917, 2, 727. 81 If the lost l)lood were in the systemic veins, further- more, it shcHild be possible jjromjitly to remedy the condition of a shocked individual liy placing his body in a slanting head-down position, bandaging the limbs, and compressing the abdomen. Such measures have been thoroughly tried in treating shock, and though perhaps in some cases heli)ful, they do not give results which indicate that the blood which is out of circula- tion is stagnant in the large venous channels. The fact should be remembered that veins are to a considerable extent subject to vasoconstrictor impulses; and if conditions are such as to continue the activity or to induce an overactivity of the vasoconstrictor center, the veins as well as the arteries might be contracted. Venbmotor nerves have not been demonstrated for all parts of the body, however, and if there are veins free from nervous control, other influences causing relaxa- tion might prevail. Only slight dilation, perhaps too little to be conspicuous, would be needed to increase considerably the venous capacity. But there are no observations that the veins are even slightly dilated in shock. IN THE CAPILLARIES? If in wound shock the lost blood is not in the arteries and probably not to a great amount in the veins, it must be mainly stagnant in the capillaries. Observations reported in a previous paper^^ have shown that in shock a striking discrepancy exists between the corpuscular content of the capillaries and the veins. There is a concentration of the blood and a stagnation of the cor- puscles in the capillaries which can be demonstrated in such widely separated parts as the ears, the fingers and the toes. The discrepancy is, to be sure, more marked in superficial areas than in deeper regions ; but even in the latter a noteworthy difference is found. The question immediately occurs. Is the capillary capacity sufficient to contain the lost blood in shock? Unfortunately, the data for estimating the capillary capacity are not definitely established, and it is impossi- ble to state with any assurance what amount of blood these vessels may contain. Ranke inferred from deter- minations made on freshly killed rabbits that approxi- _ 35. Cannon, W. B.; Eraser, John, and Hooper, A. N.: Some Altera- tions in Distribution and Character of Blood in Shock and Hemorrhage, p. 32. 82 match' oiu- fiiurlli nl" tin.' lilood is in the luart, lungs and m'cal hlootl vessels, one fuurlh in ihe liver, one fourth in the restiujjj luuseles, and one fourth in the icmaininj; orjj^ans."" 'ihe larj^e projiorlion of the hlood. about 75 per cent., which is outside the heart, lungs and large veins and arteries, seems to indicate an abundant capacity in the small vessels lying within the tissues. On the other hand, an estimation of the capacity of the cajMllaries, based on the inverse ratio Ijetween the rate of flow and the cross-section, yields a rather small vol- ume for capillary contents. The most favorable ratio of the rate of flow in the aorta and in the capillaries, stated by Tigerstedt,"" is 2,000:1. The cross-section of the aorta of an adult man is about 4.4 sq.cni. ; that cf the total cajMllary bed, on this basis, would be (4.4X 2,000) S,800 sq.cm. The average length of a cajMllary is given as 0.05 cm. The total capacity of the capillary system, therefore, would be only about 440 c.c. This calculation docs not take into consideration, however, the fact that capillaries are not all full of blood. J kubncr^'' observed after injecting sodium gold chlorid the sudden appearance of new capillaries in the frog's web, so that a coarse mesh was quickly changed to a fine one. And Worm-Muller"" was convinced that the only way to account for the ability of the circulatory system to accommodate itself to injection of large amounts of blood was to assume a utilization of capil- laries not ordinarily filled. He cited the dift'erence of a])pearance of the intestine when at rest and when digesting, the phenomenon of blushing and the redness of the inflamed skin as illustrating the idea that the capillary net may contain much more blood than it usu- ally contains. The distcnsibility of the cai)illaries also should be considered, for Roy and Brown^" noted that chloroform could double the diameter of capillaries (thus quadrupling their capacity). Still another con- sideration which is pertinent to the conditions in shock is the concentration of the ca])illary blood, as shown in a previous paper,""' which means a retention mainly of 36. Vierordt: Anatomische, Physiologische unci Physikalische Daten und Tabellen, Jen.i, 1893. 37. Tigerstedt: Physiologic des Kreislaufcs, Leipzig, 1893, p. 423. 38. Ileubner: Arch. f. Exper. Path. u. Pharniakol., 1907, 56, 375. 39. Worm-Miillcr: Ber. u. d. Vcrhandl. a. k. Sachs. Gcs. d. Wissensch., 1873, 25, 650. 40. Roy and Brown: Jour. Physiol., 1879, », 375. 83 corpuscles in tlic ca])illarics. All (licsc facts appear to warrant the conclusi(Mi that the ca])illary rapacity is .sufficient to contain the lost blood in shock, atul tliat the chances of its doinj^ so arc }:(reater (he mfjrc concen- trated the lost blood becomes. The observations ])reviously reportcMl''"' indicated tliat the capillary blood may be concentrated to such an extent that a cubic millimeter contains - 3'---> Fig. 1. — ]\Ietliod of carrying a dry blanket. method has already been put into practice in a large part of the line. All regimental stretchers at advanced bearer posts in the front line, and stretchers carried by working parties, should be equipped with this packet. The regimental bearers should be insistently instructed by their medical officer as to the importance of doing everything to prevent wound shock. The wounded 96 man should be fj^iiardcd as much as possible against loss of heat. Efticient first-aid should be given rapidly without unduly exjjosing the patient to the cold for a prolonged period. A hot drink should be given at the earliest moment. Then, having been carefully wrapped up. the patient should be carried down wilh all speed to the regimenlal aid post. A well trained, intelligent orderly might be entrusted to give a tablet of morphin (one-fourth grain) by mouth in cases of severe pain. A note of this treatment should be made in the usual way. At the regiincnta! aid post it is wise to consider the general condition of the patient first and his wound second. A dry stretcher with three blankets should always be in readiness for a possible case at any time of the day or night. In the properly equipped aid post there will be a constant source of heat, such as can be supplied by any good type of small closed stove or a small open brazier with a flue to carry off coke fumes. Space will be limited ; but an open stretcher, together with three blankets folded lengthwise three times, may be kept supi)orted horizontally against the wall of the dugout behind the stove. A dry stretcher and a supply of warm blankets will thus always be at hand. A tin of water may be kept standing on the fire to provide for hot drinks and for filling hot-water bottles. As soon as a patient arrives he should be given a few ounces of hot drink, and his wet boots and puttees removed, along with any other clothing which may cover wounds. Meanwhile the dry stretcher is prepared by arranging the first two blankets so that four folds will come underneath the patient (Fig. 2). The blankets are covered temporarily with a water- proof sheet to prevent soiling while wounds are being dressed. The man is now transferred to this prepared stretcher, which is supported on trestles and stands well over the stove. The third or free fold of each of the lower two blankets hangs (Unvn on either side and helps to form an enclosed warming chamber. If there is no constant source of heat, a hot air chamber may be made in a few minutes by use of a Primus or Beatrice stove.^ 2. A Primus stove of ordn.Tnce pattern will burn a gallon of paraflin in twenty-four hours if operating continuously. 97 The patient is lunv bcroiiiiiij^' vvaniicd, whih; the me(hcal officer is atteiKhnj,' to the sur^^ical cleansini^ of the wounds and neij^hhcjrinj^ parts, and is a])];lying projjcr dressinj^^s and sjjhnts. As sgon as the dressings are finished, weU guarded h(jt water bottles arc placed in each axiUa and a third across tlie loins or between the legs; and the thirrl blanket, which is doubled lengthwise, is laid over the patient. The two warmed blankets which have been hanging to form the sides of the hot air chamber are IJfted, carried over the patient, and tucked in. lie now has four folds of blanket over him as well as underneath. Finally, just before the patient is sent off, he is given a hot drink 'of sweetened tea in which a dram of sodium bicarbonate is dissolved. ilSp^-s^ BU^Uh-l --eUU.N'z fS3 a..^. Fig. 2. — Method of folding three blankets to give four folds above and below the patient; also the formation of a hot air chamber. At the advanced dressing station the warming proc- ess with the Primus stove may be repeated, but usually without changing the stretcher and blankets. Meanwhile, any necessary treatment is carried out. Before the patient is sent on, a hot sweetened alkaline drink is administered as described above, and a fresh set of hot water bottles is put in place. The next stage of the journey is usually undertaken by means of some mechanical transport, such as a narrow gage railway or a motor ambulance. The cars are at present warmed, so that there is a lessened chance of loss of body heat on the final stages of the journey. At the clearing statio)i, application of warmth should be emphasized as the most important part of the treat- ment in all serious cases. \\'hile the patient is being 98 undressed ami iiuule ready for operation, he should be put over the same hot air chamber as has already been described. Electric warming apparatus, to be set over the patient, is at hand to aj^ply as soon as he is ready, but it will not permit handlinp^ and treatment as will the hcatin_sj[ from below. W bile c)peratini'i:kativi-: i'kci'Iiylaxis When a wounded man, hadly shocked, is hrought to a clearino- station, he commonly must he oj)erated on in spite of a low hlood ])ressure and its attendant acidosis. The lapse of time when a man is in this condition gives op]K)rtiniity for the extension of infec- tive {processes which gravely menace his chances. The surgeon has to choose, therefore, hetween an opera- tion when the risk is serious, and a delay during which toxemia may develop to a menaciiig degree. The low hlood pressure of shock has heen met hitherto hy the injection of normal or hy])ertonic salt solution, or hy comhinations of salt solutions and gum. There is no doubt that in some cases such injections have had definitely beneficial effects. As shown in the previous papers, part of the pathology of shock is due to a loss of fluid from the circulation and con- sequent concentration of the hlood. The injection of salt solution adds fluid to the body and improves the circulation, so that the concentration is soon abolished," and the ^•iscosity of the stagnant blood lessened. In such cases, however, the degree of acidosis had not been determined, and injection of physiologic sodium chlorid solution or Ringer's solution makes no provi- sion against such critical turns as have been encoun- tered during operation or shortly thereafter in con- sequence of increased acidosis." Not only does ordi- nary salt xjjution fail to combat acidosis, it actually increases an already existent acidosis. Milroy"" has recently shown that hemorrhage results in a loss of reserve alkali, and that then injection of sodium chlorid solution alone causes a greater Il-ion concen- tration of the blood exposed to a given pressure of carbon dioxid than was present before the injection. 6. Cannon, W. B.; Fra.ser, John, and Hooper, A. N. : Some Altera- tions in Distriliution and Character of Blood in Shock and Hemorrhage, p. 32, Cases 65 a and 60 a. 7. Cannon, \V. B. : Acidosis in Cases of Shock, HeniorrhaKC nnd Ci.-is Infection, p. 47. 8. Milroy: Jour. Physiol., 1917. 51, 277-279. 101 Wh.'il is w.'ink'd is a fliiiH lliat will have the arlvan- 1a<;c's already (Icnioiislralcd for salt solutions ■ — thin- ning of .concentrated blood, lessening of viscosity and increase of blood flow with restoration of arterial pressure — together with antagonism to the state oi acidosis. vSuch a fluid is found in sodium bicarbonate solution. I lowell" observed years ago that alkaline injections (sodium bicarbonate) into a vein or info the rectum raised a systolic pressure of 60 or 70 mm. permanently to the normal level, and caused a marked increase in the force of the heart beats. If the pres- sure was lower (from 20 to 30 mm.) it was raised to 60 or 70 mm. Also the efifects were relatively per- manent, lasting one or more hours. These observa- tions were confirmed by Dawson.^" Either intravenous or intrarectal injections of sodium bicarbonate can restore the alkali reserve and abolish an existent acidosis. ^^ Injection of a fluid that will increase blood pressure has dangers in itself. Hemorrhage in a case of shock may not have occurred to a marked degree because blood pressure has been too low and the flow too scant to overcome the obstacle offered by a clot. If the pressure is raised before the surgeon is ready to check any bleeding that may take place, blood that is sorely needed may be lost. Fortunately, the injection may be made at the start of operation, just after the patient has been prepared and when the surgeon is ready to stop any hemorrhage, and it may continue as the operation proceeds. The fluid that was injected in the cases recorded below was a 4 per cent, solution of sodium bicarbo- nate. Since 1.5 per cent, sodium bicarbonate is approx- imately isotonic wath the blood plasma, the 4 per cent, solution is rather strongly hypertonic. It had previ- ously been employed, however, in treating cases of diabetic coma,^- and if introduced slowly (at the rate of an ounce a minute), it causes no noteworthy altera- tion of the blood. The fluid should, of course, be delivered to the body at approximately body tempera- ture — it may be a few degrees warmer, but should not be colder, than that. If the solution is passed 9. Howell: Am. Jour. Phvsiol., 1900, 4. 14. 10. Dawson: Am. Tour. Phvsiol.. 1904, 10. 35. 11. Milroy: Jour. Physiol., 1917, 51, 278-2S1. 12. Peabody: Am. Jour. Med. Sc, 1916, 151. 198. 102 tlirniic[h a tube of oonsidciahlc lent^th before it enters the \cin. it should ha\e a temperature maintained I)etwecn 110 and 115 F. Tlie boibng of sodium l)icarbonate in solution ehanges it to sodium carbonate. Since the bicarbonate should be injected, it should not be boiled. The solu- tion should be made just before it is to be used, by the addition to warm sterile water the ])r()|)er amount of the sterile salt." To inject the solution it is usually not necessary to lay bare a vein and introduce a cannula. If a small rubber tube is drawn around the upper arm as a tourniquet and held by a looped twist (not so tightly as to obstruct the arterial flow, which, it will be notecl, has a low pressure), the veins in the elbow will in most cases become sufticientiy prominent to permit a hollow needle to be introduced into one of them. The lumen of the needle should Ije large enough to permit a pint of the bicarbonate solution to pass in fifteen or twenty minutes when the head of pressure is only 2 or 3 feet. A glass reservoir marked in ounces permits a judgment as to the proper rate of flow. As soon as the needle enters the vein, an outflow of blood through the lumen gives evidence. When the blood thus appears, the tourniquet should be pulled loose, the rubber tul)ing full of the solution should be connected with the needle, and the flow allowed to start. In some few cases the veins are so obscure as to make this procedure difficult or impossible ; in that case the needle or a small cannula must be inserted into the bared vessel. The following cases illustrate results which have been obtained when the solution of sodium bicarbonate has been injected in the manner described above: Private R. M., wounded 9:30 p. m., Septeml)er 24, sustain- ing a compound fracture of llie left tibia and fil)ula, and a wound of tlie liand, was. admitted, 11:30, .September 25, with 13. An ideal injection fluid for shock cases would be a solution with colloid added, as Bayliss (Proc. Roy. Soc, 1916, 89. 380) has sug- gested, for example, one containing sodium hicarhonatc in proper amount and 6 per cent, gum acacia. (Sec further Bayliss: Injections to Replace Blood, Memorandum 1, of Reports of the Special Investigation Commit- tee on Surgical Shock and Alhed Conditions, Nov. 25, 1917.) Unfor- tunately, tlie gum contains calcium, which precipitates as calcium car- bonate as sodium bicarbonate is added. If this precipitate is filtered out, the solution has the advantages of being both alkaline and viscous. The Medical Research Committee is preparing to provide in bottles sterile solutions of 6 per cent, gum, to which 2 per cent, sodium bicarbonate has been added, and the deposit filtered out. 103 severe gas infection of tlie leg; lemi)erature %; hloof] pres- sure, 96 and 50. Operation was begun at 12:40; tlic carhon (lioxid capacity, 40 jjcr cent. One pint of sodium liicarhonate solution was injeclcd. Operation ended at 1:25; Mood pres- sure, 100 and 60; carhon dioxid capacity, 6.^ per cent. The pressure was lower in the afternoon (4:30), 74 and 46, hut the next morning it was 112 and 66, and it did not again fall helow normal limits. Private J. B. was admitted, Septemher 24, willi a gunsliot wound of the head (three deep lacerations), contusifjn of left eye, fracture of hoth l)oncs of the left leg, and the left foot hlown off. Unconscious from cerebral injury. Blood pres- sure at 11:35, 54 and 20. Operation begun at 11:47; carI;on dioxid capacity, 42 per cent. One pint of sodium bicarbonate solution was injected. Operation ended 12:22; blood pres- sure 112 and 40; carbon dioxid capacity, 58 per cent. The patient lived until the evening of the next day, and died with- out regaining consciousness. Private F. B. was admitted, September 9, with one foot mangled and wounds of the right thigh and right shoulder. Wounded at 3:30 a. m.; at 11:30 a. m., just after admission, temperature 98.4, pulse 144, blood pressure 75 and 46; sweat- ing, thirsty, face and lips pale. Operation begun at 2 p. m. ; pulse 144, blood pressure 72 and 42, carbon dioxid capacity, 36 per cent. One pint of sodium Ijicarbonate was injected. Operation ended at 2:40; pulse 120, blood pressure 104 and 50. At 11 : 30 the pulse was 110, but as the patient was asleep the pressure was not taken. The next day (9 a. m.), pulse 98, blood pressure 128 and 70. Gas infection required removal of leg in the afternoon. The patient stood the operation well, and made a smooth recovery. Private H. H. was admitted, October 3, with the left foot blown off; he had lost much blood. The pulse was thready and rapid. Operation was started at 5:10; systolic pressure 62; diastolic pressure unreadable; carbon dioxid capacity, 42 per cent. One pint of sodium bicarbonate solution was injected. Operation ended at 5:40; blood pressure 62 and 46; pulse slow and easily palpable. The next morning (9:30), pulse 96, blood pressure 104 and 72. The patient recovered. Private F. W. was admitted. September 26, with a com- pound fracture of the left thigh and a wound of the left hand. Wounded 11 p. m., September 25. At 4 a. m., Septem- ber 26, just after admission, temperature was 96.6, pulse 132, blood pressure 98 and 70. Operation was begun at 4 : 50 ; carbon dioxid capacity, 34 per cent. Pressure fell to 82 and 50, pulse 160. One pint of sodium bicarbonate solution w-as injected. At 5:35, blood pressure was 110 and 85. carbon dioxid capacity, 68 per cent. At 9:15 a. m.. blood pressure 124 and 90, and at 4:30 p. m., pulse 120, blood pressure 128 and 98. A smooth recovery followed. 104 Sonictitncs a patient a])|)arfntly in a condition tit for operation becomes badly shocked as the operation proceeds. The foUowinjj case illustrates the use of the bicarbonate solution in such circumstances : Private D. was wouiulcd by shrapnel at 10:vW a. m., Sep- icinlier 19. He complained of sweating within less than five minutes of being hit. Seen by Cowell at 11 p. m. ; pulse 96, blood pressure 104 and 70; cold, pallid, sweating. Admitted to the clearing station at 11:45; I)lood pressure 82 and 70, pulse 96, temperature 96. At operation ten large tears of the small intestine were found, and much blood in the abdominal cavity. At the end of operation the blood pressure was unreadable. One pint of sodium bicarbonate solution was injected; blood pressure rose to 85 and 60. In the evening the pressure was 86 and 60. The following morning it was 82 and 60, and the patient was in excellent condition. That evening the pressure was 102 and 80. On the next morning, September 21, the pressure was 112 and 90. The recovery was uneventful. The foregoing cases slunv liial an alkaline injection at the start of anesthesia prevents the dangerous depressive efYects which the anesthetic and operative ]^rocedures have in cases of shock with acidosis. The operation ends, not with an increase of the existent acidosis, but with the acidosis overcome and a normal alkaline reserve provided. And the blood pressure, instead of being perilously lowered, is actually raised during the critical period. The blood pressure may fall to some extent later, but the improved state of the patient during operation is unmistakable, and the subsequent course of shock cases in which operation has been performed with the precautions described above has been highly gratifying. In concluding this scries of papers, we take pleasure in expressing our thanks to Col. Cuthbert Wallace, C. M. C, A. M. S., and to Col. T. R. Elliott for facilitating arrange- ments to carry on the work and for counsel ; to Lieut.-Col. Winder, R. A. M. C, for cooperative interest; and to the Medical Research Committee and the American Red Cross in France for instruments used in the investigations. COLUMBIA UNIVERSITY LIBRARIES 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 arrange- ment with the Librarian in charge. DATE BORROWED DATE DUE DATE BORROWED DATE DUE i C2B(|14i)mIOO COLUMBIA IJNIVFHSITY LIBRARIES (hsi.six) Rd 131 G792 1918 C.1 Th(! n;iluii; .nut ticiliinMil of //oiiiul '.liock ;^oo:>i:^/i'jb RD131 't.T'rit. Nat. comm G792 I'leairifl] foccov^v, .^,