Ventricular fibrillation (VF) is a lethal heart rhythm that leads to cardiac arrest. It has been shown that amplitude spectral area (AMSA) in prolonged VF correlates with success of resuscitation. This study will compare traditional resuscitation with a novel resuscitation algorithm using AMSA and end-tidal carbon dioxide (ETCO2) to time defibrillations.VF will be induced in 60 swine. Resuscitation will commence after 10 minutes of untreated VF. Cases will receive defibrillation if AMSA is >19.8 mVHz and ETCO2 >20 mm of Hg, otherwise chest compressions will continue for another 90 seconds. Controls will have standard resuscitation. Sub group analysis will include effect of induced myocardial infarction (MI).End points will include survival, neurologic scores, duration of resuscitation efforts, and number of defibrillations.This experiment will establish whether using AMSA and ETCO2 to time defibrillations results in superior resuscitation compared with standard techniques.