A defibrillator is a device that performs defibrillation on the chambers of the heart. The device may be implanted in the user of the device. If so, it is known as an implantable cardioverter-defibrillator or(much less frequently) an internal cardiac defibrillator (ICD).

External defibrillators are available in all hospitals and are commonly available in ambulances. The use of external defibrillators is taught in advanced cardiac life support.

Defibrillators have often been depicted in television and movies set in emergency room environments as the ultimate lifesaving measure which pulls back a frail or severely injured patient from the brink of death. A defibrillator is the familiar electronic machine connected to two metal paddles which the attending physician grabs when the patient's heart stops. A nurse applies conducting gel, then the attending physician shouts "clear," everyone else yanks their hands away from the patient, the physician shocks the patient, and then everyone glances at the electrocardiogram monitor to see if the shock worked.

In recent years, automated external defibrillators have been made available for use by the general public. These devices are commonly found in large gathering places, such as airports, casinos, and sports stadiums.

See also

CPR, advanced cardiac life support, cardioversion, implantable cardioverter-defibrillator, defibrillation, automated external defibrillator