Sudden Cardiac Arrest and Automated External Defibrillators

ut of hospital sudden cardiac arrest (SCA) is the major (approximately 66-94.5%) 2] The annual occurrence of sudden death is 350,000-450,000 in the United States, 10.5 per 100,000 population in United Kingdom and 37 per 100,000 in Japan. In the United States, there were 341,780 reported cases of out of hospital sudden cardiac death in 1999, which accounted for 47% of all cardiacrelated deaths. Identifying the individual at risk for cardiac arrest remains difficult, and approximately 20% of people who suffer from SCA do not have any prior cardiac history. Despite an increase in public awareness and implementation of several programs to rescue individuals from SCA, as well as advances in preventive therapy, the proportion of out-of-hospital SCA has increased 23.5% over the past decade. ost of the SCAs are reversible if acted upon in a timely and organized fashion. According to the American Red Cross health and safety service, it is estimated that at least 30-50% deaths from SCA could have been prevented if a cardiac chain of survival had been initiated and an automated external defibrillator (AED) had been available for immediate use (within 5 min) at the time of the SCA. Survival from out of hospital cardiac arrest depends upon an urgent and very efficient integrated system of stepwise care, symbolized by the American Heart Association's (AHA) 4-step of chain of survival: (1) early access to emergency medical system, (2) early initiation of cardiopulmonary resuscitation (CPR), (3) early defibrillation and (4) early advanced life support system.