OHCA is a major cause of unexpected deaths in developed countries. Summary data from 37 communitiesin Europe indicated that the annual incidence of emer-gency medical services-treated OHCA for all rhythms is38 per 100,000 population. Based on these data, thesurvival rate to hospital discharge is 10.7% for all-rhy-thm and 21.2% for VF cardiac arrest.10 Recent data from10 North American sites had similar findings. in that themedian survival rate to hospital discharge was 8.4%from any rhythm and 22.0% after VF.1 There is some evidence that long-term survival rates after cardiac arrestare increasing.11 In patients initially resuscitated, anoxicneurologic injury is an important cause of morbidity and mortality.12 In one report, OHCA in the U.S. had a mortality rate greater than 90% resulting in more than300,000 deaths per year, and only 3% of the patientswere discharged with good neurological outcomes.13Those who survive the devastating event often retain ahypoxic brain injury and a permanently incapacitatingneurologic defect.14