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Defibrillation is a life-saving medical procedure used to restore normal heart rhythm in patients suffering from cardiac arrest. It involves delivering an electric shock to the heart, interrupting the chaotic electrical activity, and re-establishingits own normal rhythm.

Defibrillation is most commonly performed using an automated external defibrillator (AED) device.

  • The first step in performing defibrillation is to assess the patient’s condition and determine if they are in cardiac arrest.
  • If they are, then CPR should be started immediately. This will help keep oxygenated blood circulating through the body until the defibrillator can be used.
  • Once CPR has been started, the AED should be used as soon as possible.
  • The AED contains two paddles or electrodes that are placed on either side of the patient’s chest. These paddles detect abnormal electrical activity in the heart and deliver an electric shock when necessary.
  • Before delivering a shock, however, it is important for healthcare providers to analyze the patient’s heart rhythm with an electrocardiogram (ECG). This will allow them to determine if a shock is necessary and how much energy should be delivered by the AED.
  • Once all these steps have been completed, the AED can deliver a shock that interrupts any abnormal electrical activity and restores normal sinus rhythm.
  • After this has been done, CPR should continue until medical personnel arrive or until spontaneous circulation returns.


Defibrillation is a critical part of saving lives during cardiac arrest events and can make all the difference between life and death for many patients who suffer from this condition. Healthcare professionals need to understand how this procedure works so that they can provide effective care when needed.

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Frequently Asked Questions

What is an AED?

An Automated External Defibrillator, mostly known as AED, is a portable lifesaving device to help people experiencing abnormal heart rhythms. It is an easy-to-use medical device that can analyze the victim's heart's rhythm and provide an electrical shock, if needed, to restore the normal heartbeat

Are there any low shock treatments to resync an arrhythmia?

Treatment for arrhythmias will depend on whether you have Tachycardia or bradycardia. Some arrhythmias do not need treatment, and your healthcare provider may recommend regular checkups to monitor your condition. Treatment for arrhythmias may include medications, therapies such as vagal maneuvers, cardioversion, catheter procedures, or heart surgery.

Do you give the same shock energy to adults and children when using an AED?

No. The energy shock for younger children is lesser compared to adults. That's why there are AEDs that have pediatric settings and pads that modify the energy level used. AEDs are safe for young children aged 1-8 and weigh less than 55 pounds, even though they are designed with adults in mind. For infants, a manual defibrillator is preferred over automated defibrillators.


  • American Heart Association (2020). Automated External Defibrillators (AEDs). Retrieved from,of%20the%20heart's%20rhythm%20back .
  • Mayo Clinic Staff (2019). Defibrillation - Overview & Facts. Retrieved from https://www.mayoclinicproceedingsinnovationsqualitysafetycareersinmedicine/article/S2542-5196(19)30246-3/fulltext .