Defibrill

Defibrill, or defibrillation, is a medical procedure that uses an electrical shock to reset the heart’s electrical activity and restore a normal rhythm. It is a core treatment for certain life-threatening arrhythmias, most notably ventricular fibrillation and pulseless ventricular tachycardia. The goal is to terminate chaotic electrical activity so the heart’s natural pacemaker can regain control.

External defibrillation is delivered by defibrillators, including automated external defibrillators (AEDs) and manual devices used by trained personnel. Pads placed on the chest deliver a controlled electrical shock; modern biphasic devices typically use a single shock energy around 120-200 joules. The device analyzes the rhythm and instructs a shock when a shockable rhythm is detected. Defibrillation is usually performed in conjunction with immediate cardiopulmonary resuscitation.

Implantable cardioverter-defibrillators (ICDs) are surgically implanted devices with heart leads that monitor rhythm and can deliver therapy automatically. They provide pacing for certain slow rhythms and high-energy shocks to terminate ventricular fibrillation or pulseless ventricular tachycardia. ICDs require periodic follow-up and battery replacement, and may deliver multiple shocks over time, sometimes without warning to the patient.

Indications and limitations: defibrillation is life-saving for select arrhythmias but does not address the underlying heart disease. Its success depends on rapid response, appropriate rhythm detection, and concurrent resuscitation when needed. Risks include skin burns, myocardial injury, inappropriate shocks, and device malfunctions. Defibrillation is one component of broader emergency and cardiac care protocols.

History: defibrillation research dates to the mid-20th century, with early trials by Claude Beck and subsequent advances in external paddles, portable AEDs, and implantable devices that have improved response times and survival in sudden cardiac arrest.