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Cardiac Resuscitation
CARDIAC RESUSCITATION JULIAN JOHNSON, M.D., D.Se. (MEn), F.A.C.S.* CHARLES K. KIRBY, M.D.t
A sufficient number of patients have been returned to normal health following cardiac resuscitation to make it evident that effort expended in that direction is worthwhile. It is equally evident to those interested in this field that if the occasional patient whose heart is in asystole is to be resuscitated, the operating team involved must act quickly, according to a preconceived plan. It is unlikely that any patient will be saved by a surgeon who has not previously thought out his plan of attack. When a patient develops sudden cardiac arrest, the greatest problem is that of speed in making the diagnosis and instituting treatment. The brain must not be deprived of oxygenated blood for more than three to four minutes. Therefore, within this short period of time, the surgeon must produce an adequate blood flow by cardiac massage and the anesthetist must insure oxygenation of the blood by adequate ventilation of the lungs. Since cardiac arrest is an emergency in which one cannot wait for consultation it would seem to be worthwhile for every surgeon and anesthetist to understand the various aspects of this problem so that a life may be saved if the opportunity should present itself. ETIOLOGY
The cause of cardiac asystole has a great deal to do with the prognosis. Thus when one is thinking of cardiac resuscitation, death from the usual medical causes is not included. Success can seldom be expected unless the emergency arises in the operating room. Even then success is unlikely when dealing with a patient with severe myocardial injury. A favorable situation for cardiac resuscitation is that of a patient with a normal heart who has received an overdose of an anesthetic. Here the problem is simply that of producing artificial circulation and respiration until enough of the anesthetic agent is removed, or destroyed, to allow the heart to start beating again. This includes not only patients under general anesthesia but also patients who are sensitive to or perhaps have received an intravenous injection of a local anesthetic. From the Surgical Clinic of the Hospital of the University of Pennsylvania, and the Harrison Department of Surgical Research, Schools of Medicine, University of Pennsylvania, Philadelphia. * Professor of Surgery, School of Medicine, University of Pennsylvania; Assistant Surgeon, Hospital of the University of Pennsylvania. t Associate in Surgery, i&chool of Medicine, University of Pennsylvania: Assistant Surgeon, Hospital of the University of Pennsylvania. ,
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JULIAN
JOHNSON, CHARLES K. KIRBY
When cardiac arrest or ventricular fibrillation is incident to anoxia, the brain may well have been damaged considerably before cardiac action ceased. The period of arrested circulation which can be tolerated is decreased accordingly (Case IV). It is sometimes difficult to account for sudden cardiac arrest when the heart has no demonstrable lesioll and anoxia or an overdose of an anesthetic does not appear to be a contributory factor. It has been thought that reflex phenomena (vago-vagal reflexes) are responsible. In such a situation the heart will usually start beating again rather easily, and if the time interval is not over three minutes the prognosis is good (Case I). DIAGNOSIS
Delay in diagnosis is the chief cause of failure in cardiac resuscitation. The anesthetist must maintain constant observation of the patient if he is to notice asystole the moment it occurs. Having noticed the absence of a pulse or blood pressure the question always arises as to whether the heart is beating so feebly as to be undetectable, or whether the heart is in standstill or ventricular fibrillation. In many instances a fatal delay is caused by futile efforts to confirm the diagnosis before proceding with· the proper treatment. If the surgeon happens to be operating in the vicinity of the heart or a large artery he may immediately confirm the diagnosis by putting his hand directly on the heart or large artery. If the surgeon is operating in the abdomen his first reaction should be to feel the heart through the diaphragm. Auscultation of the chest is not apt to be helpful when the pulse and blood pressure are not obtainable. If the heart is beating so feebly as not to give a pulse or sustain the blood pressure it is unlikely that it can be heard with a stethoscope. Time spent by the surgeon looking for a stethoscope if one is not immediately available is· time ill spent. It has been reported that one may diagnose cardiac arrest immediately with an ophthalmoscope. l It is said that the retinal arteries will not be visible and the column of blood will be broken up into short segments in the veirur. We are convinced, on the basis of personal experience, that this method is of no practical value, and doubt that it is reliable even in the hands of an experienced ophthalmologist. It has been suggested that the absence of capillary refill indicates cardiac arrest. We can say that the presence of cardiac refill does not necessarily indicate cardiac activity for we have observed it as long as half an hour after the heart had been seen to be still. Even if one happens to have an electrocardiograph attached to the· patient at the time of cardiac arrest it may not be helpful, for N egovski2 has observed that the heart can produce an electrocardiogram, though an abnormal one, for some time after it has stopped beating. It becomes obvious from the above that the only reliable method of determining whether the patient is in cardiac asystole is to see or feel
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the heart or a large artery. Weare convinced therefore that the surgeon should take the point of view that opening the thorax to feel the heart is a diagnostic procedure. We believe that when the patient's pulse and blood pressure suddently cannot be obtained, the chest should be opened immediately without losing valuable time attempting unreliable diagnostic procedures. Once the decision has been made to open the chest the surgeon should be prepared to do it with the greatest dispatch. Every surgeon therefore should give some thought as to the quickest and easiest method, should the occasion arise. The surgeon needs only a pair of gloves and a scalpel. Given these he should have his hand on the heart in ten to fifteen seconds. Skin antiseptics and sterile drapes are refinements which can be added when available but their absence should not cost the patient his life. The inCision should be made in the left fourth interspace from about the edge of the sternum to the posterior axillary line. Since there is no bleeding the incision can be carried quickly through the chest wall and pleura. The surgeon can then readily put one hand between the .fourth and fifth ribs to feel the heart. The diagnosis will be immediately apparent. If arrested the heart will be still and if in ventricular fibrillation it will feel like a "bag of worms." TREATMENT
In the presence of cardiac asystole the problem is one of producing adequate blood flow by cardiac massage and adequate oxygenation of the blood by artificial ventilation of the lungs. Respiration.-Adequate respiration can be maintained with an anesthesia machine, by manual compression of the breathing bag. A tightfitting face mask is satisfactory. It is not wise to take time to insert an endotracheal tube until the patient is again well oxygenated. One hundred per cent oxygen should be used. • If the emergency should arise out of the operating room, the bag and mask technic, or the Kreiselman bellows resuscitator can be used. Until they are available the patient's lungs should be ventilated by the mouth to mouth technique. Circulation.-As soon as the surgeon puts his hand on the heart and finds it is not beating he should start compressing it rhythmically. If a rib spreader is not immediately available he should divide the fourth and fifth cartilages with a knife or scissors in his left hand as he compresses the heart with his right hand in order to give better exposure and prevent the ribs from pressing against his hands. Even after this the rib spreader is ·of great help. Following cardiac massage a few open vesseis will begin to bleed and must be caught as soon as hemostats are available. There are a number of factors which greatly influence the effectiveness of the blood flow produced by cardiac massage. 1. Rate of Cardiac Massage.-A review of the literature reveals a dif-
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JULIAN JOHNSON, CHARLES K. KIRBY
ference of opinion as to the rate at which the heart should be compressed. Most writers recommend twenty to forty times a minute, in order to allow the ventricles to fill adequately, while a few have suggested a normal rate. Because of this difference of opinion we recently studied .the problem in dogs. The results are reported elsewhere. 3 Using the bubble meter of Dumke and Schmidt 4 in the thoracic aorta, it was found that a greater blood flow was produced when the heart was compressed at a rapid rate. Rates of 30, 60 and 120 per minute were compared. In all instances the blood flow increased as the rate of compression was increased regardless of whether the heart felt full or empty. As the result of these experiments we became convinced that in clinical use one should compress the heart as rapidly as possible, up to 120 times per minute. The fatigue of the operator makes a rate of 120 times per minute impossible for more than a few minutes whereas he can continue for a long time at sixty to eighty times per minute. If there are two or more operators who can take turns, a faster rate may be constantly maintained. 2. Technic of Cardiac M assage.-In the laboratory it was found that some practice was required to produce an effective blood flow by cardiac massage. The dog's heart can be compressed most effectively by placing the thumb in front and the fingers behind, or the thumb and index finger in front and the other three fingers behind the heart. It was found that the blood flow produced by compressing the heart against the arterior chest wall was only about one-half as great as by the above method. Only one-fifth as much blood flow could be produced by compressing the heart through the diaphragm with one hand in the abdomen. The amount of blood flow produced by artificial respiration alone was too small to be measurable by this technic. Any hope that artificial respiration is an effective method of producing blood flow should be abando~ed. A small human heart may be compressed with one hand, as in the dog. The usual adult heart can be more effectively compressed, with less effort, by placing one hand in front and one behind the heart. 3. Blood Volume.-It was found in the laboratory that the filling of the heart is very important in producing an effective blood flow even though it was not profitable to wait for it to fill between cardiac compressions. The cardiac output varied directly with the rate. Nevertheless the cardiac output could be greatly increased by rapid transfusion of blood, plasma or plasma substitutes. When intravenous fluids were given rapidly the heart could be felt to fill more completely and the cardiac output was found to be increased greatly even though the compression rate remained the same. 4. Diverrsion of Blood Flow.-In most instances the heart will resume beating fairly soon if it is going to do so. Occasionally it may start up after a prolonged period of artificial respiration and circulation. In such instances it may be well to divert a good part of the blood flow to the
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brain since it is most severely affected by anoxia, whereas in normal adults the descending thoracic aorta can be clamped for 30 minutes with no ill effects. We were able to show that the carotid blood flow was greatly increased by occluding the aorta. Drugs.-We have felt that no drugs are helpful in getting the heart to start beating again. Once the heart has started epinephrine may be useful in increasing the tone of the cardiac muscle and the effectiveness of its contraction. We have seldom used it. It does increase the probability of ventricular fibrillation. Procaine may be useful to decrease the likelihood of the development of ventricular fibrillation, and in restoring normal rhythm in the event of ventricular fibrillation. We use it routinely. Ventricular Fibrillation.-If, when the thorax is opened, the heart is found in ventricular fibrillation, or if it should develop during the cardiac massage, the problem takes on another aspect. The usual causes of ventricular fibrillation are anoxia, mechanical trauma, electric shock, and drugs which increase the irritability of the heart. Clinically, anoxia results commonly from coronary occlusion, or respiratory obstruction during anesthesia. The heart may be stimulated by manipulation during many intrathoracic operations but ventricular fibrillation has occurred most commonly during operations upon the heart and pericardium. Local and intravenous procaine have been shown both experimentally and clinically to protect the heart against irregularities resulting from mechanical stimulation.5 In rare instances ventricular fibrillation has reverted to normal rhythm sponta~eously. In some the use of drugs may cause reversion, as happened recently in one of our patients (Case IV). Nearly always, however, countershock therapy, developed by Wiggers6 and by Beck and Mautz 7 must be employed. This method of treatment is based on the observation that passage of a strong current through the heart will cause a simultaneous contraction of all the incoordinated, fibrillating fibers, and relaxation follows. The heart is then in standstill. In animals, the spontaneous heartbeat resumes after a short period of cardiac massage. In the patients' hearts defibrillated by us, the spontaneous heartbeat has begun after a short interval of standstill. Before defibrillation is attempted, anoxia must be overcome by cardiac massage and artificial ventilation of the lungs with 100 per cent oxygen. Three cubic centimeters of 2 per cent procaine are injected into the right ventricle and an equal amount into the pericardial cavity unless procaine has previously been given intravenously. The electrodes are then placed on each side of the ventricles and an alternating current (60 cycles) of 1 to 1.5 amperes is passed through the heart for less than a second. Repetition of the shock may be necessary. The strength of the current is of importance, for it has been shown that, in animals, 0.4 amperes for 5 seconds will cause fibrillation, whereas 0.8 amperes or more will stop it. A current of 0.8 amperes will not cause fibrillation and 0.45 amperes will not stop it.s
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JULIAN JOHNSON, CHARLES K. KIRBY
CLINICAL EXPERIENCE
While cardiac arrest and ventricular fibrillation are uncommon, they do occur from time to time on any active surgical service. During the past two years, since our previous report,9 we have had six patients whose hearts have been resuscitated, at least temporarily. Four of these occurred in the operating room. Three of the patients are alive and well. The fourth was decerebrate and died on the thirty-ninth postoperative day. Two who developed cardiac asystole outside the operating room died within forty-eight hours after cardiac resuscitation. In two other instances cardiac massage was attempted under circumstances which appeared all but hopeless. Spontaneous heartbeat was not restored and these cases are not described. CASE I: S. H., a boy aged 9, was undergoing left lowerlobectomy, in the facedown position, for bronchiectasis. The lobe had been removed and the pleural flap was being elevated from over the vagus nerve. The surgeon was not noticing the heart particularly when an assistant called attention to the fact that the heart was not beating. The heart had probably been in asystole less than a minute when it was noticed, as the anesthetist noticed the absence of a pulse simultaneously. Following cardiac massage the heart started to beat again within thirty seconds. The operation was completed without difficulty. Postoperatively the patient showed "no signs of anything unusual having occurred.
This may be an example of the vago-vagal reflex. If anoxia was present it was not apparent as judged by the patient's color. CASE II:* J. E., a man aged 26, was being subjected to a left lower lobectomy for bronchiectasis in the lateral position. A nitrous oxide, oxygen and ether mixture was being used for anesthesia. The patient was lightly enough anesthetized to move as the skin incision was made. In the subcutaneous layer there was free bleeding and the blood was bright red. When the muscular layer was cut there was no bleeding. At the same time the anesthetist could not feel a pulse. The incision was carried rapidly through the sixth interspace and the sixth and seventh ribs spread sufficiently to insert one hand. The heart was still. After about fifteen seconds of massage the heart began to contract feebly and gradually returned to normal. The patient's blood flow was probably stopped less than one to two minutes. At no time was the patient cyanotic. It was de<\ided therefore to proceed with the lobectomy. There was no evidence of anything unusual during the postoperative period.
We were unable to account for the cardiac arrest in this patient. We felt that he had not had an overdose of anesthetic and are sure that he was not anoxic. CASE III:t H. S., a man aged 49, was being anesthetized with cyClopropane and ether anesthesia preparatory to a Smithwick sympathectomy for hyper-
* This patient was operated upon at the Valley Forge General Hospital. t Resuscitation in Cases III and IV was by Dr. H. A. Zintel.
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tension. The anesthetist suddenly noted an absence of pulse and blood pressure. The surgeon who was scrubbed and standing by was called to the anesthesia room. He immediately opened the chest and found the heart still. With cardiac massage the heart resumed beating in less than half a minute. It was thought the cardiac massage was started within two to three minutes of the time the heart stopped. The sympathectomy was abandoned and the chest closed. There was no evidence of damage to the central nervous system postoperatively. The cause of the cardiac arrest in this case was probably anoxia along with a vago-vagal reflux due to respiratory obstruction and difficulty in inserting an intratracheal tube. CASE IV: A. S., a man aged 52, was undergoing the second stage of the Smithwick sympathectomy for hypertension. The surgeon thought that the patient's blood had been dark on several occasions during the operation, but the anesthetist thought that there was no real trouble until the diaphram was being closed. The patient developed a series of jerking motions and there appeared to be some respiratory obstruction. The endotracheal tube was removed and a face mask substituted for the pressure breathing necessitated by the pleural cavity being open. This did not work satisfactorily and an endotracheal tube was reinserted. The patient had become severely cyanotic during this procedure. The heart beat became feeble and finally stopped. The surgeon turned the patient over and opened the left chest. The heart was still. After a few moments massage, the heart started again. Ventilation of the lungs was now satisfactory and the patient's color improved. The estimated time of cardiac arrest was from three to four and one-half minutes. The period of cerebral anoxia was probably longer than this, since anoxia was probably the cause of the cardiac arrest. Although the cardiorespiratory action returned to normal, the patient never regained consciousness as a result of the cerebral damage from the prolonged anoxia. He was fed by a gastric tube and a tracheotomy was done to help keep his lungs clear. However, he never showed signs of cerebrate cortical activity and died of respiratory complications on the thirty-ninth postoperative day. CASE V: F. K., a woman aged 74, was about to undergo cystoscopy and was lying on a litter outside the operating room. She had had angina pectoris for several years. Her only preoperative medication had been 0.05 gm. of demerol. An attendant passing by heard her sigh and called a resident, who found no signs of life. She was taken into an operating room and positive pressure ventilation with an anesthesia machine was begun. A surgeon operating in the next rc~om was called about three minutes later and the left chest was immediately opened. The heart was still. Cardiac massage was begun at.a rapid rate and after about two minutes the characteristic twitchings of ventricular fibrillation were felt. Following the first minute of cardiac massage, her color became good and remained so. While getting the defibrillator, cardiac massage was continued and 3 cc. of procaine (2 per cent) was injected into the right ventricle. About seven minutes after cardiac massage was begun, the electrodes were applied and two strong counter shocks were thrown into the heart. After a brief period of inactivity (2 seconds) spontaneous forceful heartbeats resumed, in normal rhythm. Sp-ontaneous respirations began twenty minutes later. Following operation the patient began to respond after six hours and soon became overactive and emotional. Twenty-four hours after cardiac resuscitation she recognized people she knew and obeyed simple commands. About forty
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JULIAN JOHNSON, CHARLES K. KIRBY
hours after operation her blood pressure began to fall, she lapsed into coma, and her heart stopped beating within an hour. At autopsy this patient was found to have extensive myocardial fibrosis. Had it not been for preexisting myocardial disease she might possibly have recovered. There probably would have been permanent cerebral changes of at least moderate degree. The period of cardiac arrest was probably between four and five minutes. CASE VI: E. D., a woman aged 29, had returned to her room following a total hysterectomy four hours previously. She had not recovered sufficiently from anesthesia to recognize her husband but was tossing about the bed and, because of this, was given h grain of dilaudid. A short time later, after being out of the room, her husband returned and found her blue and gasping for breath. A few minutes later artificial ventilation with a Kreiselman bellows was started and from ten to fifteen minutes later a surgeon was called. Since her color had improved with artificial ventilation of the lungs, an attempt at resuscitation was made. The left chest was opened through the fourth interspace and the fourth and fifth costal cartilages were divided. The heart was still. After cardiac massage for one and one-half to two minutes ventricular fibrillation was noted. While waiting for the defibrillator, procaine 100 mg. was given intravenously and normal spontaneous rhythm resumed, with contractions becoming increasingly strong. After operation spontaneous respirations did not resume and reflexes could never be obtained. The patient died thirty hours later in a respirator.
It seems likely that the death of this patient was due to respiratory obstruction and the cardiac arrest to anoxia. Comment.-These case reports illustrate many of the points discussed above. The only patients who recovered fully were those in whom cardiac arrest occurred on the operating table or in the anesthetizing room. Prompt diagnosis and treatment averted injury to the anoxiasensitive brain cells. In all of these patients the heart responded quickly to manual stimulation and resumed its normal rhythm. Case V is of unusual interest because an attempt at cardiac resuscitation in a patient who apparently died spontaneously has not been pre-· viously recorded, to our knowledge. The occurrence of ventricular fibrillation in Cases V and VI, which followed standstill and cardiac massage, was probably largely due to increased irritability of the cardiac muscle resulting from anoxia. It is probably because of the close interrelationship of anoxia and ventricular fibrillation that defibrillation in humans has been discouragingly unsuccessful. As far as we know, Beck10 has had the only fully successful case of defibrillation. SUMMARY
1. The methods and technics which had proved successful in resuscitating patients with cardiac arrest and ventricular fibrillation have been discussed.
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2. Success in' cardiac resuscitation depends upon the restoration of the flow of oxygenated blood to the brain within three to four minutes. All other considerations are of secondary importance. 3. Since the time limit of three to four minutes cannot be exceeded when this emergency arises, all surgeons and anesthetists should become familiar with the technic of cardiac resuscitation. REFERENCES 1. Iokhveds, B. 1.: Intracardiac Blood Transfusion. Am.' Rev. Soviet Med.
3:116, 1945. 2. Negovski, V. A.: Agonal States and Clinical Death: Problems in Revival of Organisms; the Electrocardiogram during Death and Revival. Am. Rev. Soviet Med. 2:491, 1945. 3. Johnson, J. and Kirby, C. K.: An Experimental Study of Cardiac Massage. Surgery. To be published. 4. Dumke, P. R. and Schmidt, C. F.: Quantitative Measurements of Cerebral Blood Flow in the Macacque Monkey. Am. J. Physiol. 138:421, 1943. 5. Burstein, C. L.: Treatment of Acute Arrhythmias During Anesthesia by Intravenous Procaine. Anesthesiology 7:113, 1946. 6. Wiggers, C. J.: Cardiac Massage Followed by Countershock in Revival of Mammalian Ventricles from Fibrillation Due to Coronary Occlusion. Am. J. Physiol. 116:161, 1936. 7. Beck, C. S. and Mautz, F. R.: The Control of the Heart Beat by the Surgeon. Ann. Surg. 108:525, 1937. ' 8. Hooker, D. R., Kouwenhoven, W. B. and Langworthy, O. R. The Effect of Alternating Electrical Currents on the Hearts. Am. J. Physiol. 103:444, 1933. 9. Dripps, R. D., Kirby, C. K., Johnson, J. and Erb, W. H.: Cardiac Resuscitatation. Ann. Surg. 127:592, 1948. 10. Beck, C. S.: Personal communication.
A sufficient number of patients have been returned to normal health following cardiac resuscitation to make it evident that effort expended in that direction is worthwhile. It is equally evident to those interested in this field that if the occasional patient whose heart is in asystole is to be resuscitated, the operating team involved must act quickly, according to a preconceived plan. It is unlikely that any patient will be saved by a surgeon who has not previously thought out his plan of attack. When a patient develops sudden cardiac arrest, the greatest problem is that of speed in making the diagnosis and instituting treatment. The brain must not be deprived of oxygenated blood for more than three to four minutes. Therefore, within this short period of time, the surgeon must produce an adequate blood flow by cardiac massage and the anesthetist must insure oxygenation of the blood by adequate ventilation of the lungs. Since cardiac arrest is an emergency in which one cannot wait for consultation it would seem to be worthwhile for every surgeon and anesthetist to understand the various aspects of this problem so that a life may be saved if the opportunity should present itself. ETIOLOGY
The cause of cardiac asystole has a great deal to do with the prognosis. Thus when one is thinking of cardiac resuscitation, death from the usual medical causes is not included. Success can seldom be expected unless the emergency arises in the operating room. Even then success is unlikely when dealing with a patient with severe myocardial injury. A favorable situation for cardiac resuscitation is that of a patient with a normal heart who has received an overdose of an anesthetic. Here the problem is simply that of producing artificial circulation and respiration until enough of the anesthetic agent is removed, or destroyed, to allow the heart to start beating again. This includes not only patients under general anesthesia but also patients who are sensitive to or perhaps have received an intravenous injection of a local anesthetic. From the Surgical Clinic of the Hospital of the University of Pennsylvania, and the Harrison Department of Surgical Research, Schools of Medicine, University of Pennsylvania, Philadelphia. * Professor of Surgery, School of Medicine, University of Pennsylvania; Assistant Surgeon, Hospital of the University of Pennsylvania. t Associate in Surgery, i&chool of Medicine, University of Pennsylvania: Assistant Surgeon, Hospital of the University of Pennsylvania. ,
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JULIAN
JOHNSON, CHARLES K. KIRBY
When cardiac arrest or ventricular fibrillation is incident to anoxia, the brain may well have been damaged considerably before cardiac action ceased. The period of arrested circulation which can be tolerated is decreased accordingly (Case IV). It is sometimes difficult to account for sudden cardiac arrest when the heart has no demonstrable lesioll and anoxia or an overdose of an anesthetic does not appear to be a contributory factor. It has been thought that reflex phenomena (vago-vagal reflexes) are responsible. In such a situation the heart will usually start beating again rather easily, and if the time interval is not over three minutes the prognosis is good (Case I). DIAGNOSIS
Delay in diagnosis is the chief cause of failure in cardiac resuscitation. The anesthetist must maintain constant observation of the patient if he is to notice asystole the moment it occurs. Having noticed the absence of a pulse or blood pressure the question always arises as to whether the heart is beating so feebly as to be undetectable, or whether the heart is in standstill or ventricular fibrillation. In many instances a fatal delay is caused by futile efforts to confirm the diagnosis before proceding with· the proper treatment. If the surgeon happens to be operating in the vicinity of the heart or a large artery he may immediately confirm the diagnosis by putting his hand directly on the heart or large artery. If the surgeon is operating in the abdomen his first reaction should be to feel the heart through the diaphragm. Auscultation of the chest is not apt to be helpful when the pulse and blood pressure are not obtainable. If the heart is beating so feebly as not to give a pulse or sustain the blood pressure it is unlikely that it can be heard with a stethoscope. Time spent by the surgeon looking for a stethoscope if one is not immediately available is· time ill spent. It has been reported that one may diagnose cardiac arrest immediately with an ophthalmoscope. l It is said that the retinal arteries will not be visible and the column of blood will be broken up into short segments in the veirur. We are convinced, on the basis of personal experience, that this method is of no practical value, and doubt that it is reliable even in the hands of an experienced ophthalmologist. It has been suggested that the absence of capillary refill indicates cardiac arrest. We can say that the presence of cardiac refill does not necessarily indicate cardiac activity for we have observed it as long as half an hour after the heart had been seen to be still. Even if one happens to have an electrocardiograph attached to the· patient at the time of cardiac arrest it may not be helpful, for N egovski2 has observed that the heart can produce an electrocardiogram, though an abnormal one, for some time after it has stopped beating. It becomes obvious from the above that the only reliable method of determining whether the patient is in cardiac asystole is to see or feel
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the heart or a large artery. Weare convinced therefore that the surgeon should take the point of view that opening the thorax to feel the heart is a diagnostic procedure. We believe that when the patient's pulse and blood pressure suddently cannot be obtained, the chest should be opened immediately without losing valuable time attempting unreliable diagnostic procedures. Once the decision has been made to open the chest the surgeon should be prepared to do it with the greatest dispatch. Every surgeon therefore should give some thought as to the quickest and easiest method, should the occasion arise. The surgeon needs only a pair of gloves and a scalpel. Given these he should have his hand on the heart in ten to fifteen seconds. Skin antiseptics and sterile drapes are refinements which can be added when available but their absence should not cost the patient his life. The inCision should be made in the left fourth interspace from about the edge of the sternum to the posterior axillary line. Since there is no bleeding the incision can be carried quickly through the chest wall and pleura. The surgeon can then readily put one hand between the .fourth and fifth ribs to feel the heart. The diagnosis will be immediately apparent. If arrested the heart will be still and if in ventricular fibrillation it will feel like a "bag of worms." TREATMENT
In the presence of cardiac asystole the problem is one of producing adequate blood flow by cardiac massage and adequate oxygenation of the blood by artificial ventilation of the lungs. Respiration.-Adequate respiration can be maintained with an anesthesia machine, by manual compression of the breathing bag. A tightfitting face mask is satisfactory. It is not wise to take time to insert an endotracheal tube until the patient is again well oxygenated. One hundred per cent oxygen should be used. • If the emergency should arise out of the operating room, the bag and mask technic, or the Kreiselman bellows resuscitator can be used. Until they are available the patient's lungs should be ventilated by the mouth to mouth technique. Circulation.-As soon as the surgeon puts his hand on the heart and finds it is not beating he should start compressing it rhythmically. If a rib spreader is not immediately available he should divide the fourth and fifth cartilages with a knife or scissors in his left hand as he compresses the heart with his right hand in order to give better exposure and prevent the ribs from pressing against his hands. Even after this the rib spreader is ·of great help. Following cardiac massage a few open vesseis will begin to bleed and must be caught as soon as hemostats are available. There are a number of factors which greatly influence the effectiveness of the blood flow produced by cardiac massage. 1. Rate of Cardiac Massage.-A review of the literature reveals a dif-
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JULIAN JOHNSON, CHARLES K. KIRBY
ference of opinion as to the rate at which the heart should be compressed. Most writers recommend twenty to forty times a minute, in order to allow the ventricles to fill adequately, while a few have suggested a normal rate. Because of this difference of opinion we recently studied .the problem in dogs. The results are reported elsewhere. 3 Using the bubble meter of Dumke and Schmidt 4 in the thoracic aorta, it was found that a greater blood flow was produced when the heart was compressed at a rapid rate. Rates of 30, 60 and 120 per minute were compared. In all instances the blood flow increased as the rate of compression was increased regardless of whether the heart felt full or empty. As the result of these experiments we became convinced that in clinical use one should compress the heart as rapidly as possible, up to 120 times per minute. The fatigue of the operator makes a rate of 120 times per minute impossible for more than a few minutes whereas he can continue for a long time at sixty to eighty times per minute. If there are two or more operators who can take turns, a faster rate may be constantly maintained. 2. Technic of Cardiac M assage.-In the laboratory it was found that some practice was required to produce an effective blood flow by cardiac massage. The dog's heart can be compressed most effectively by placing the thumb in front and the fingers behind, or the thumb and index finger in front and the other three fingers behind the heart. It was found that the blood flow produced by compressing the heart against the arterior chest wall was only about one-half as great as by the above method. Only one-fifth as much blood flow could be produced by compressing the heart through the diaphragm with one hand in the abdomen. The amount of blood flow produced by artificial respiration alone was too small to be measurable by this technic. Any hope that artificial respiration is an effective method of producing blood flow should be abando~ed. A small human heart may be compressed with one hand, as in the dog. The usual adult heart can be more effectively compressed, with less effort, by placing one hand in front and one behind the heart. 3. Blood Volume.-It was found in the laboratory that the filling of the heart is very important in producing an effective blood flow even though it was not profitable to wait for it to fill between cardiac compressions. The cardiac output varied directly with the rate. Nevertheless the cardiac output could be greatly increased by rapid transfusion of blood, plasma or plasma substitutes. When intravenous fluids were given rapidly the heart could be felt to fill more completely and the cardiac output was found to be increased greatly even though the compression rate remained the same. 4. Diverrsion of Blood Flow.-In most instances the heart will resume beating fairly soon if it is going to do so. Occasionally it may start up after a prolonged period of artificial respiration and circulation. In such instances it may be well to divert a good part of the blood flow to the
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brain since it is most severely affected by anoxia, whereas in normal adults the descending thoracic aorta can be clamped for 30 minutes with no ill effects. We were able to show that the carotid blood flow was greatly increased by occluding the aorta. Drugs.-We have felt that no drugs are helpful in getting the heart to start beating again. Once the heart has started epinephrine may be useful in increasing the tone of the cardiac muscle and the effectiveness of its contraction. We have seldom used it. It does increase the probability of ventricular fibrillation. Procaine may be useful to decrease the likelihood of the development of ventricular fibrillation, and in restoring normal rhythm in the event of ventricular fibrillation. We use it routinely. Ventricular Fibrillation.-If, when the thorax is opened, the heart is found in ventricular fibrillation, or if it should develop during the cardiac massage, the problem takes on another aspect. The usual causes of ventricular fibrillation are anoxia, mechanical trauma, electric shock, and drugs which increase the irritability of the heart. Clinically, anoxia results commonly from coronary occlusion, or respiratory obstruction during anesthesia. The heart may be stimulated by manipulation during many intrathoracic operations but ventricular fibrillation has occurred most commonly during operations upon the heart and pericardium. Local and intravenous procaine have been shown both experimentally and clinically to protect the heart against irregularities resulting from mechanical stimulation.5 In rare instances ventricular fibrillation has reverted to normal rhythm sponta~eously. In some the use of drugs may cause reversion, as happened recently in one of our patients (Case IV). Nearly always, however, countershock therapy, developed by Wiggers6 and by Beck and Mautz 7 must be employed. This method of treatment is based on the observation that passage of a strong current through the heart will cause a simultaneous contraction of all the incoordinated, fibrillating fibers, and relaxation follows. The heart is then in standstill. In animals, the spontaneous heartbeat resumes after a short period of cardiac massage. In the patients' hearts defibrillated by us, the spontaneous heartbeat has begun after a short interval of standstill. Before defibrillation is attempted, anoxia must be overcome by cardiac massage and artificial ventilation of the lungs with 100 per cent oxygen. Three cubic centimeters of 2 per cent procaine are injected into the right ventricle and an equal amount into the pericardial cavity unless procaine has previously been given intravenously. The electrodes are then placed on each side of the ventricles and an alternating current (60 cycles) of 1 to 1.5 amperes is passed through the heart for less than a second. Repetition of the shock may be necessary. The strength of the current is of importance, for it has been shown that, in animals, 0.4 amperes for 5 seconds will cause fibrillation, whereas 0.8 amperes or more will stop it. A current of 0.8 amperes will not cause fibrillation and 0.45 amperes will not stop it.s
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JULIAN JOHNSON, CHARLES K. KIRBY
CLINICAL EXPERIENCE
While cardiac arrest and ventricular fibrillation are uncommon, they do occur from time to time on any active surgical service. During the past two years, since our previous report,9 we have had six patients whose hearts have been resuscitated, at least temporarily. Four of these occurred in the operating room. Three of the patients are alive and well. The fourth was decerebrate and died on the thirty-ninth postoperative day. Two who developed cardiac asystole outside the operating room died within forty-eight hours after cardiac resuscitation. In two other instances cardiac massage was attempted under circumstances which appeared all but hopeless. Spontaneous heartbeat was not restored and these cases are not described. CASE I: S. H., a boy aged 9, was undergoing left lowerlobectomy, in the facedown position, for bronchiectasis. The lobe had been removed and the pleural flap was being elevated from over the vagus nerve. The surgeon was not noticing the heart particularly when an assistant called attention to the fact that the heart was not beating. The heart had probably been in asystole less than a minute when it was noticed, as the anesthetist noticed the absence of a pulse simultaneously. Following cardiac massage the heart started to beat again within thirty seconds. The operation was completed without difficulty. Postoperatively the patient showed "no signs of anything unusual having occurred.
This may be an example of the vago-vagal reflex. If anoxia was present it was not apparent as judged by the patient's color. CASE II:* J. E., a man aged 26, was being subjected to a left lower lobectomy for bronchiectasis in the lateral position. A nitrous oxide, oxygen and ether mixture was being used for anesthesia. The patient was lightly enough anesthetized to move as the skin incision was made. In the subcutaneous layer there was free bleeding and the blood was bright red. When the muscular layer was cut there was no bleeding. At the same time the anesthetist could not feel a pulse. The incision was carried rapidly through the sixth interspace and the sixth and seventh ribs spread sufficiently to insert one hand. The heart was still. After about fifteen seconds of massage the heart began to contract feebly and gradually returned to normal. The patient's blood flow was probably stopped less than one to two minutes. At no time was the patient cyanotic. It was de<\ided therefore to proceed with the lobectomy. There was no evidence of anything unusual during the postoperative period.
We were unable to account for the cardiac arrest in this patient. We felt that he had not had an overdose of anesthetic and are sure that he was not anoxic. CASE III:t H. S., a man aged 49, was being anesthetized with cyClopropane and ether anesthesia preparatory to a Smithwick sympathectomy for hyper-
* This patient was operated upon at the Valley Forge General Hospital. t Resuscitation in Cases III and IV was by Dr. H. A. Zintel.
r
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I
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tension. The anesthetist suddenly noted an absence of pulse and blood pressure. The surgeon who was scrubbed and standing by was called to the anesthesia room. He immediately opened the chest and found the heart still. With cardiac massage the heart resumed beating in less than half a minute. It was thought the cardiac massage was started within two to three minutes of the time the heart stopped. The sympathectomy was abandoned and the chest closed. There was no evidence of damage to the central nervous system postoperatively. The cause of the cardiac arrest in this case was probably anoxia along with a vago-vagal reflux due to respiratory obstruction and difficulty in inserting an intratracheal tube. CASE IV: A. S., a man aged 52, was undergoing the second stage of the Smithwick sympathectomy for hypertension. The surgeon thought that the patient's blood had been dark on several occasions during the operation, but the anesthetist thought that there was no real trouble until the diaphram was being closed. The patient developed a series of jerking motions and there appeared to be some respiratory obstruction. The endotracheal tube was removed and a face mask substituted for the pressure breathing necessitated by the pleural cavity being open. This did not work satisfactorily and an endotracheal tube was reinserted. The patient had become severely cyanotic during this procedure. The heart beat became feeble and finally stopped. The surgeon turned the patient over and opened the left chest. The heart was still. After a few moments massage, the heart started again. Ventilation of the lungs was now satisfactory and the patient's color improved. The estimated time of cardiac arrest was from three to four and one-half minutes. The period of cerebral anoxia was probably longer than this, since anoxia was probably the cause of the cardiac arrest. Although the cardiorespiratory action returned to normal, the patient never regained consciousness as a result of the cerebral damage from the prolonged anoxia. He was fed by a gastric tube and a tracheotomy was done to help keep his lungs clear. However, he never showed signs of cerebrate cortical activity and died of respiratory complications on the thirty-ninth postoperative day. CASE V: F. K., a woman aged 74, was about to undergo cystoscopy and was lying on a litter outside the operating room. She had had angina pectoris for several years. Her only preoperative medication had been 0.05 gm. of demerol. An attendant passing by heard her sigh and called a resident, who found no signs of life. She was taken into an operating room and positive pressure ventilation with an anesthesia machine was begun. A surgeon operating in the next rc~om was called about three minutes later and the left chest was immediately opened. The heart was still. Cardiac massage was begun at.a rapid rate and after about two minutes the characteristic twitchings of ventricular fibrillation were felt. Following the first minute of cardiac massage, her color became good and remained so. While getting the defibrillator, cardiac massage was continued and 3 cc. of procaine (2 per cent) was injected into the right ventricle. About seven minutes after cardiac massage was begun, the electrodes were applied and two strong counter shocks were thrown into the heart. After a brief period of inactivity (2 seconds) spontaneous forceful heartbeats resumed, in normal rhythm. Sp-ontaneous respirations began twenty minutes later. Following operation the patient began to respond after six hours and soon became overactive and emotional. Twenty-four hours after cardiac resuscitation she recognized people she knew and obeyed simple commands. About forty
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JULIAN JOHNSON, CHARLES K. KIRBY
hours after operation her blood pressure began to fall, she lapsed into coma, and her heart stopped beating within an hour. At autopsy this patient was found to have extensive myocardial fibrosis. Had it not been for preexisting myocardial disease she might possibly have recovered. There probably would have been permanent cerebral changes of at least moderate degree. The period of cardiac arrest was probably between four and five minutes. CASE VI: E. D., a woman aged 29, had returned to her room following a total hysterectomy four hours previously. She had not recovered sufficiently from anesthesia to recognize her husband but was tossing about the bed and, because of this, was given h grain of dilaudid. A short time later, after being out of the room, her husband returned and found her blue and gasping for breath. A few minutes later artificial ventilation with a Kreiselman bellows was started and from ten to fifteen minutes later a surgeon was called. Since her color had improved with artificial ventilation of the lungs, an attempt at resuscitation was made. The left chest was opened through the fourth interspace and the fourth and fifth costal cartilages were divided. The heart was still. After cardiac massage for one and one-half to two minutes ventricular fibrillation was noted. While waiting for the defibrillator, procaine 100 mg. was given intravenously and normal spontaneous rhythm resumed, with contractions becoming increasingly strong. After operation spontaneous respirations did not resume and reflexes could never be obtained. The patient died thirty hours later in a respirator.
It seems likely that the death of this patient was due to respiratory obstruction and the cardiac arrest to anoxia. Comment.-These case reports illustrate many of the points discussed above. The only patients who recovered fully were those in whom cardiac arrest occurred on the operating table or in the anesthetizing room. Prompt diagnosis and treatment averted injury to the anoxiasensitive brain cells. In all of these patients the heart responded quickly to manual stimulation and resumed its normal rhythm. Case V is of unusual interest because an attempt at cardiac resuscitation in a patient who apparently died spontaneously has not been pre-· viously recorded, to our knowledge. The occurrence of ventricular fibrillation in Cases V and VI, which followed standstill and cardiac massage, was probably largely due to increased irritability of the cardiac muscle resulting from anoxia. It is probably because of the close interrelationship of anoxia and ventricular fibrillation that defibrillation in humans has been discouragingly unsuccessful. As far as we know, Beck10 has had the only fully successful case of defibrillation. SUMMARY
1. The methods and technics which had proved successful in resuscitating patients with cardiac arrest and ventricular fibrillation have been discussed.
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2. Success in' cardiac resuscitation depends upon the restoration of the flow of oxygenated blood to the brain within three to four minutes. All other considerations are of secondary importance. 3. Since the time limit of three to four minutes cannot be exceeded when this emergency arises, all surgeons and anesthetists should become familiar with the technic of cardiac resuscitation. REFERENCES 1. Iokhveds, B. 1.: Intracardiac Blood Transfusion. Am.' Rev. Soviet Med.
3:116, 1945. 2. Negovski, V. A.: Agonal States and Clinical Death: Problems in Revival of Organisms; the Electrocardiogram during Death and Revival. Am. Rev. Soviet Med. 2:491, 1945. 3. Johnson, J. and Kirby, C. K.: An Experimental Study of Cardiac Massage. Surgery. To be published. 4. Dumke, P. R. and Schmidt, C. F.: Quantitative Measurements of Cerebral Blood Flow in the Macacque Monkey. Am. J. Physiol. 138:421, 1943. 5. Burstein, C. L.: Treatment of Acute Arrhythmias During Anesthesia by Intravenous Procaine. Anesthesiology 7:113, 1946. 6. Wiggers, C. J.: Cardiac Massage Followed by Countershock in Revival of Mammalian Ventricles from Fibrillation Due to Coronary Occlusion. Am. J. Physiol. 116:161, 1936. 7. Beck, C. S. and Mautz, F. R.: The Control of the Heart Beat by the Surgeon. Ann. Surg. 108:525, 1937. ' 8. Hooker, D. R., Kouwenhoven, W. B. and Langworthy, O. R. The Effect of Alternating Electrical Currents on the Hearts. Am. J. Physiol. 103:444, 1933. 9. Dripps, R. D., Kirby, C. K., Johnson, J. and Erb, W. H.: Cardiac Resuscitatation. Ann. Surg. 127:592, 1948. 10. Beck, C. S.: Personal communication.