Thorax: first published as 10.1136/thx.7.3.205 on 1 September 1952. Downloaded from Thorax (1952), 7, 205. CARDIAC ARREST AND VENTRICULAR FIBRILLATION * A METHOD OF TREATMENT BY ELECTRICAL SHOCK BY I. K. R. MCMILLANt F. B. COCKETT, AND P. STYLES Froml the Departnment of Cardiology, tile Professorial Surgical Unit, and tile Departalzent of Phlysical Medicine, St. Thomlas's Hospital, London (RECEIVED FOR PUBLICATION APRIL 30, 1952) Cardiac arrest during operation is a subject of VENTRICULAR FIBRILLATION importance to all surgeons. During intra-thoracic The treatment of ventricular fibrillation bv operations cardiac arrest and ventricular fibrilla- electrical shock therapy is not new and was first tion can be differentiated by direct observation of tried experimentally in 1899 (Prevost and Battelli). the heart. In recent years this method has been extensively Ventricular fibrillation is an incoordinated type investigated in the United States and France of contraction which produces no useful beats. (Kouwenhoven and Kay, 1951; Johnson and The typical rippling movements of the ventricular Kirby, 1951 ; Santy and Marion, 1950). muscle are unmistakable when seen or felt with The treatment of ventricular fibrillation by the hand directly on the heart. The treatment of zlectrical shock gives encouraging results in the copyright. a heart that has stopped is cardiac massage and experimental animal, and may be a useful adjunct adequate oxygenation. The treatment of ventri- in the operating theatre during cardiac and general cular fibrillation which we recommend is, first, surgery. Under these conditions shock therapy massage to maintain the oxygen supply to the can be rapidly applied. Provided that adequate heart through the coronary arteries, followed oxygenation is maintained and direct cardiac mas- http://thorax.bmj.com/ rapidly by electrical shocking to restore normal sage promptly initiated and maintained, shock rhythm therapy can be applied without undue haste. In abdominal operations, however, or during operations elsewhere in the body, once the pulse METHOD becomes undetectable most surgeons waste no time The principle of the method is to apply a powerful in performing a quick midline upper abdominal shock across the ventricles and produce complete incision and massaging the heart through the dia- arrest of the fibrillating heart. Once asystole occurs phragm. At the same time adrenaline is given a regular ventricular beat may start spontaneously or either intravenously, intramuscularly, or more cardiac massage may be needed to initiate it. on September 27, 2021 by guest. Protected usually directly into the ventricle. The latter is The apparatus comprises a double-wound trans- a most dangerous procedure, as it is now known former having a tapped secondary capable of supply- that one of the effects of adrenaline on a heart ing I ampere from any tapping. The primary circuit is supplied from 50 c/s mains via a foot-operated which is already anoxic may be the production of switch and a Londex motor-driven interrupter whose ventricular fibrillation. Until recent years ventri- contacts close every 1.5 seconds for 0.5 second. cular fibrillation was almost always fatal. The output voltage tappings are selected by means The purpose of this paper is twofold: (1) to of a rotary switch on the front panel. Available emphasize once again the dangerous effects of voltages are 85, 125, 185, 250. 270, and 300. A buzzer to describe the lead- operated from an auxiliary winding on the transformer adrenaline ; (2) experiments gives an audible warning that the electrodes are alive. ing up to the development of a satisfactory elec- Closure of the mains switch merely sets in motion the trical instrument for defibrillating the heart. interrupter. In order to administer a shock the foot * This work was assisted by a grant from the Endowment Fund of switch must be depressed. St. Thomas's Hospital. The consist t MacKenzie MacKinnon Research Fellow of the Royal College electrodes of two large curved plates of Physicians and the Royal College of Surgeons. which are shaped to fit the curve of the ventricles. 0 Thorax: first published as 10.1136/thx.7.3.205 on 1 September 1952. Downloaded from 206 1. K. R. McMILLAN, F. B. COCKETT, and P. STYLES FOOT SWITCH Another dog in which ven- tricular fibrillation occurred during a thoracic sympath- ectomy failed to revert to normal, probably because of inadequate oxygenation owing to of both -0 0 SELECTOR E.C.G.scollapsetaken after lungs.defibrilla- MAINS ° tion in one dog showed a regu- _ELECTRODES lar rhythm (Fig. 3). After electrical shocking sections of BUZERINDACTTOINICATOICATO ventricular muscle show some E______ superficial coagulation but no burning. Ventricular fibrilla- FIG. I .-Circuit diagram. tion is a terminal event, and any procedure with a chance The voltage required varies with the size of the heart of success is worth attempting in spite of possible and its electrical resistance, and this latter factor is minor damage. Later experiments with large elec- also governed by the efficiency of the contact between trodes showed no coagulation or burning. electrodes and heart surface. Single shocks may be sufficient to stop ventricular fibrillation or, if they are insufficient, the voltage may be increased and further RESULTS IN MAN single shocks applied. If these are still inadequate Case 1.-Mrs. T., aged 65 years, who had been a series of about six shocks at 1.5-second intervals attending as an out-patient, had gross left ventricular may be given (Wiggers, 1940). enlargement, anginal attacks, and multiple ventricular extrasystoles. During a visit to the hospital she RESULTS IN DoGs collapsed while climbing a flight of stairs. She was All dogs were under nembutal anaesthesia. found to be pulseless and respiration had almost stopped. She was put on a couch, and within copyright. three Seven dogs were given ventricular fibrillation elec- minutes the upper abdomen was opened and sub- trically by means of an induction coil. Three dogs diaphragmatic cardiac massage started. The heart have been given ventricular fibrillation by the appli- then started to beat again, but weakly, and soon cation of aconitine (one drop 0.2% solution in faded away. She was intubated and oxygen given benzene) to the auricle, which causes auricular by means of controlled respiration from an anaes- fibrillation and later ventricular fibrillation. To thetic apparatus. Next the diaphragm was incised, defibrillate the heart of a 20-kg. dog 185 volts was the pericardium was entered, and direct cardiachttp://thorax.bmj.com/ sufficient when given in a series of five shocks. massage started. A few minutes later, as the strength Nine dogs have been successfully defibrillated at of the -beat was poor, adrenaline (1 fml. of 1/1,000) periods of up to five minutes after the onset of was given intracardially. This produced a strong beat ventricular fibrillation, but in all cases cardiac mas- temporarily, but was rapidly superseded by ventricu- sage has been continued through the intervening lar fibrillation. Procaine amide hydrochloride (" pro- period. Of the three dogs chemically stimulated, two nestyl ") was injected intravenously without effect. were defibrillated with a voltage of 300. The third, Cardiac was due to other procedures on the heart, was in very massage continued, and 10 minutes later poor condition and inadequately oxygenated. the defibrillator was used. The electrodes were Ventricular fibrillation was not arrested. on September 27, 2021 by guest. Protected _ _ ~~~~*. 11 ......... .............. P~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.FIG. 2a.-The defibrillator. FIG. 2b.--The electrodes. Thorax: first published as 10.1136/thx.7.3.205 on 1 September 1952. Downloaded from CARDIAC ARREST AND VENTRICULAR FIBRILLATION "Z.07 by massage and showed no sign of returning to fibrillation. The strength of the beat, however, was poor and the heart would only beat spontaneously for about two minutes following massage. To-.ri 1-*--: i:i '--T'J---~ti;+1! ; qz;!1r After an hour the strength of the beat was getting progressively weaker and asystole followed the cessa- .f4 tion of massage. Further measures were considered ; .- }; t tz -- .*- X -- e 0 - 8 <-;4'* useless. She had not had a spontaneous respiration for half an hour and the heart was no longer filling following inspiration. LiI' .+,..o.-< .f_v= B The shock produced only slight localized muscle . _, .i. s contraction .; * outside - s -- *,, the .** e ++-^'t-' > heart. +>S_.e;i ri-.t tti V_ j _-+-1ia it-4 i tM i - i; Necropsy confirmed the above findings, and section 1*-J-.--.o ;+ of .1.,_._\X=>W99 the ventricles showed no evidence of damage due *As v>\¢ Svl. tw z.-.Fa zt-.--tet..4 to electrical shocks or burns. t/'**t...*.4* t*.._.tt Case 2.-A man of 62, suffering from polycythaemia vera, was taken to the theatre for the evacuation of a haematoma following a rib biopsy. After 60 mg. of pethidine he was given gas, oxygen, and a little cyclopropane. During this minor procedure respira- tion ceased, and at about the same time the pulse could not be felt. At once the patient was turned on to his back, a ;7'j:1 t ~- I midline upper abdominal incision was made, and the cessation of the heart beat confirmed. A transverse ._: t ....... slit in the diaphragm opposite the pericardial attach- ment was then made, four fingers thrust through this. and direct cardiac massage started. A regular but copyright. weak beat was started without difficulty. In order :^ 0 I r to strengthen this 25 at 1/1,000 adrenaline was given intracardially. Almost at once the rhythm changed from normal to ventricular fibrillation. Intracardiac & procaine " was then given without effect. Massage .|......................?....... was continued and the defibrillator was sent for. This http://thorax.bmj.com/ arrived, from another hospital, and was set up ready for use within 45 minutes of the start of cardiac massage.