The function of an AED (automated external defibrillator) is complex. It monitors heart rhythms and delivers an electric shock to the heart when it stops suddenly.
However, to use AEDs are not complicated. It is designed so that anyone – a spectator, a gym goer, a parent at a football game – can give to someone who has collapsed due to sudden cardiac arrest (SCA). Response time in this situation is very important – if CPR and AED are given within three to five minutes of collapse, the chance of survival is 70%.
Guide every step of the way
An AED is so easy to use that no training is required to administer it. The computer will tell you in each step:
- He will tell you to call 911 and put on the sticky pad.
- Then the AED will check for a heartbeat.
- If you need to be shocked, the AED will tell you to press the shock button.
- If the AED determines that it is not possible to shock, it will tell you not to shock the victim.
- The AED will tell you to give compressions if a shock is not necessary.
See Example: This one video from the American Heart Association shows how easy the AED is to use.
When in doubt, use an AED immediately
Surviving a sudden cardiac arrest depends on bystanders acting quickly.
Assume that any collapsed, unresponsive person is in cardiac arrest and apply an AED immediately. As explained above, the AED computer will determine the location of the heartbeat for you. This high level of suspicion and follow-up helps reduce delays.
It is good to know: AED is 100% accurate and not shocking to someone who doesn’t need it.
An AED will not be involved in CPR
We have heard concerns that using an AED can interfere with CPR. However, this is no longer an issue because the AHA updated their guidelines in 2025 to the following:
- Rescue breathing is no longer required during CPR.
- Because the AED gives the responder time to stop compressions and prepare for a shock, the responder will not be harmed.
- This places the importance on timely CPR and AED deployment.
SCA analysis is incomplete
I wish we had a better prevention system so AEDs wouldn’t be necessary. Currently in the United States, we screen high school athletes for life-threatening heart conditions through medical history and physical examination. Some of the athletes at the school may have had a mobile heart screen done by a hospital or organization in the area.
Although screening athletes for cardiac problems can be life-saving, this approach is imperfect in identifying many student athletes at risk for sudden cardiac arrest. Unfortunately, many young athletes can still develop SCA despite being fit and healthy.
And Cincinnati Children’s Heart InstituteWe know that using the right AED is essential to saving lives. For this reason, we work with many local companies including Congenital Heart Alliance of Cincinnati and Project Adam to ensure that local schools have the resources and training to help protect families in our area.
Until we find better methods for screening and prevention, emergency cardiac arrest is a reality for those at risk. Having an AED that is fast (unlocked), in good working order (batteries charged), and bystanders ready to use them, is the SCA victim’s best chance of survival.
LEARN MORE: Listen to this The Growth & Health Podcast which explains the warning signs and how bystanders can help when they witness an episode of sudden cardiac arrest.
