Defibrillation is a treatment for life-threatening cardiac dysrhythmias, specifically ventricular fibrillation and non-perfusing ventricular tachycardia. It is given to a patient or to an individual having cardiac arrest.
Defibrillation is often an important step in cardiopulmonary resuscitation (CPR). Defibrillation is indicated only in certain types of cardiac dysrhythmias, specifically ventricular fibrillation and pulseless ventricular tachycardia. If the heart has completely stopped, as in asystole or pulseless electrical activity, defibrillation is not indicated.
Defibrillation is also not indicated if the patient is conscious or has a pulse. Improperly given electrical shocks can cause dangerous dysrhythmias, such as ventricular fibrillation.