Fixed-energy biphasic waveform defibrillation in a pediatric model of cardiac arrest and resuscitation.
OBJECTIVE
For adults, 150-J fixed-energy, impedance-compensating biphasic truncated exponential (ICBTE) shocks are now effectively used in automated defibrillators. However, the high energy levels delivered by adult automated defibrillators preclude their use for pediatric patients. Accordingly, we investigated a method by which adult automated defibrillators may be adapted to deliver a 50-J ICBTE shock for pediatric defibrillation.


METHODS
Prospective, randomized study.


METHODS
A university-affiliated research institution.


METHODS
Domestic piglets.


METHODS
We initially investigated four groups of anesthetized mechanically ventilated piglets weighing 3.8, 7.5, 15, and 25 kg. Ventricular fibrillation was induced with an AC current delivered to the right ventricular endocardium. After 7 mins of untreated ventricular fibrillation, a conventional manual defibrillator was used to deliver up to three 50-J ICBTE shocks. If ventricular fibrillation was not reversed, a 1-min interval of precordial compression preceded a second sequence of up to three shocks. The protocol was repeated until spontaneous circulation was restored, or for a total of 15 mins. In a second set of experiments, we evaluated a 150-J biphasic adult automated defibrillator that was operated in conjunction with energy-reducing electrodes such as to deliver 50-J shocks. The same resuscitation protocol was then exercised on piglets weighing 3.7, 13.5, and 24.2 kg.


RESULTS
All animals were successfully resuscitated. Postresuscitation hemodynamic and myocardial function quickly returned to baseline values in both experimental groups, and all animals survived.


CONCLUSIONS
An adaptation of a 150-J biphasic adult automated defibrillator in which energy-reducing electrodes delivered 50-J shocks successfully resuscitated animals ranging from 3.7 to 25 kg without compromise of postresuscitation myocardial function or survival.
Tang
Wanchun
W
The Institute of Critical Care Medicine, 1695 North Sunrise Way, Building 3, Palm Springs, CA 92262-5309, USA. drsheart@aol.com
Weil
Max Harry
MH
Jorgenson
Dawn
D
Klouche
Kada
K
Morgan
Carl
C
Yu
Ting
T
Sun
Shijie
S
Snyder
David
D
D000704:Analysis of Variance; D000818:Animals; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D002648:Child; D004554:Electric Countershock / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D006323:Heart Arrest / Q000628:therapy*; D006439:Hemodynamics; D006801:Humans; D007223:Infant; D008297:Male; D010372:Pediatrics; D011897:Random Allocation; D013552:Swine; D014693:Ventricular Fibrillation / Q000628:therapy