Public access defibrillation: where does it work?

Sudden cardiac arrest (SCA) is recognized as a serious public health problem, accounting for 250 000 to 300 000 deaths per year; it is now the third-leading cause of death behind cancer and nonsudden cardiovascular deaths.1,2 Immediate, well-performed cardiopulmonary resuscitation (CPR) and early defibrillation are the only out-of-hospital interventions that improve outcomes.3 The chain of survival relies on lay responders and emergency medical services (EMS) to initiate the potentially life-saving procedures of CPR and defibrillation.