Defibrillation is the termination of ventricular fibrillation (v-fib) with electrical countershocks and is the most important intervention that a rescuer can take in patients who have suffered from cardiac arrest. The machine used for defibrillation is called a defibrillator.

There are many types of defibrillators including:

• Automated external defibrillator (AED), also called a fully automated defibrillator, which performs all of the functions needed for defibrillation on an internal computer. The operator applies pads to the chest and side of a person suffering v-fib, assures that all people are clear from the patient and then usually pushes a button to deliver the shock when prompted by the system.

• Manual defibrillator, which requires the operator to assess the need for defibrillation, select an energy level, charge the machine and deliver the shock.

• Automatic implanted cardioverter defibrillator, which is surgically implanted into patients who are at risk for sudden cardiac death caused by arrhythmia and automatically detects and treats arrhythmia.

Defibrillation at Wikipedia

On the series

Defibrillation is a method used in nearly any episode to save the patient. There have only been a few cases where the patients didn't get an electric pulse and were pronounced dead.