Article posted on March 4, 2019

Why are AEDs Important in Sudden Cardiac Arrest?

The term AED stands for Automated External Defibrillator. AEDs are used to assist rescuers through medical emergencies when an individual is experiencing a sudden cardiac arrest.         

There are several factors that can influence a patient's survival from out-of-hospital cardiac arrest. One of the most significant of these factors is the time from the patient's collapse to the time of defibrillation.                                              

AEDs analyze and detect when a patient’s heart beat is irregular and is in correctable rhythm. If the irregular heart beat is correctable, the AED will say “shock advised”. An electrical shock, known as defibrillation, is what's required to successfully restore a normal heartbeat.

If the AED has determined the rhythm is shockable, the device will deliver a shock to the victim’s heart through their chest. The shock that’s delivered is designed to temporarily stop the irregular heart beat restart it in regular rhythm.

Not all cardiac arrest victims will have a shockable rhythm. The expectation is that you continue to do CPR until EMS arrives on scene, in order to give the victim the best chance at survival.

 AEDs also have voice prompts to help guide the rescuer through the entire process. Even if you aren’t familiar with the specific AED you are using, all you have to do is listen to the voice prompts, and the device will walk you through the process.

These devices are designed to be light weight, portable and easy to use by the general public, including children and those who do not have any medical training


When a patient has gone into cardiac arrest it is important that the heart be shocked back into a regular rhythm as soon as possible for optimal survivability. The victim’s chance of survival decreases 7 – 10 percent every minute when a normal heart beat has not been restored.

Cardiopulmonary resuscitation (CPR) can delay the damage to the heart after cardiac arrest, allowing for a slightly longer time for effective defibrillation. CPR alone, however, cannot restore the heart's normal electrical function.

Help save lives by becoming familiar with AEDS and how to use them!

Please click on the link below to watch an AED Success story and to learn more information about their benefits and use.


[i] Emergency Care Programs;

Last Updated: Monday, March 04, 2019

Calgary, Alberta, Canada