Energy levels for biphasic defibrillation.

Defibrillators which deliver biphasic waveforms are rapidly replacing defibrillators which deliver monophasic waveforms. Lower energy biphasic shocks cause less myocardial injury and subsequent post-resuscitation myocardial dysfunction thus potential improving the likelihood of survival.(1-4) Recommendations of the International Liaison Committee on Resuscitation (ILCOR) state that biphasic energies less than or equal to 200 joules are as efficacious as escalating higher energy monophasic shocks.(5) However, few clinical trials in adults and none in children indicate the optimal dose of biphasic shock which would achieve maximum defibrillation rate and minimum myocardial injury. Faced with the declining availability of monophasic defibrillators and paucity of data in respect to biphasic energy levels, the Australian Resuscitation Council (ARC) makes the following recommendations.