Both the automatic external defibrillators (AED) and CPR (cardiopulmonary resuscitation) are techniques that can be used in emergencies when someone has gone into cardiac arrest – an often fatal condition in which the person loses consciousness as a result of the heart abruptly ceasing to pump blood to the body.

Although CPR is a vital life-sustaining tool, it cannot restore the patient’s heart rhythm. Defibrillation can. Research has consistently demonstrated that early defibrillation (within three to five minutes) greatly increases the survival rate of patients in cardiac arrest. Without defibrillation, however, each passing minute decreases the chance for survival by an additional 10 percent.

To help clarify when the AED is appropriate, the American Heart Association has endorsed a sequence of events to be used if someone collapses of cardiac causes. Before the AED is used, bystanders should contact emergency personnel and attempt CPR. If no signs of circulation are present after CPR and an AED is available, it should be attempted.