What Is an Automated External Defibrillator?

Dibujo Desfibrilador Automatico Esxterno An automated external defibrillator (AED) is a lightweight, portable device that delivers an electric shock through the chest to the heart. The shock can stop an irregular rhythm and allow a normal rhythm to resume in a heart in sudden cardiac arrest. Sudden cardiac arrest is an abrupt loss of heart function. If it’s not treated within minutes, it quickly leads to death. Most sudden cardiac arrests result from ventricular fibrillation. This is a rapid and unsynchronized heart rhythm originating in the heart’s lower pumping chambers (the ventricles). The heart must be “defibrillated” quickly, because a victim’s chance of surviving drops by 7 to 10 percent for every minute a normal heartbeat isn’t restored.

Why are AEDs important?
AEDs make it possible for more people to	response programs that also include rapid use
respond to a medical emergency where	of 9-1-1 and prompt delivery of CPR. All three of
defibrillation is required. Because AEDs are	these activities are critical to improving survival
portable and can be used by nonmedical	from cardiac arrest.
people, they can be made part of emergency

How does an AED work?
A built-in computer checks a victim’s heart	all activity and gives the heart an opportunity to
rhythm through adhesive electrodes. The	resume beating effectively. Instructions guide
computer calculates whether defibrillation is	the user through the process. AEDs advise a
needed. If it is, a recorded voice tells the rescuer	shock only for ventricular fibrillation or another
to press the shock button on the AED. This	life-threatening condition called pulseless
shock momentarily stuns the heart and stops	ventricular tachycardia.

Who can use an AED?

Non-medical personnel such as police, fire service personnel, flight attendants, security

guards and other lay rescuers who have been properly trained can use AEDs


Are AEDs safe to use?
AEDs are safe to use by anyone who’s been	And 95 percent of the time they are able to
trained to operate them. Studies have shown	recommend NOT shocking when the computer
that 90 percent of the time AEDs are able to	shows defibrillation is not indicated.
detect a rhythm that should be defibrillated.

Where should AEDs be placed?

All first-response vehicles, including ambulances, law-enforcement vehicles and many fire engines should have an AED. AEDs also should be placed in public areas such as sports arenas, gated

communities, airports, office complexes, doctors’ offices and any other public or private place where large numbers of people gather or where people at high risk for heart attacks live.

Where can I get AED training?

The American Heart Association offers CPR and AED training through training centers. To locate a training center, call your nearest American Heart Association office or

1-888-CPRLINE. You may also visit americanheart.org/cpr. Type in your ZIP code where requested on the home page to access contact information on training sites near you.

How can I learn more?

1. Talk to your doctor, nurse or other healthcare professionals. If you have heart disease or have had a stroke, members of your family also may be at higher risk. It’s very important for them to make changes now to lower their risk.

2. Call 1-800-AHA-USA1 (1-800-242-8721) or visit americanheart.org to learn more about heart disease.

3. For information on stroke, call 1-888-4-STROKE (1-888-478-7653) or visit StrokeAssociation.org.

We have many other fact sheets and educational booklets to help you make healthier choices to reduce your risk, manage disease or care for a loved one.

Knowledge is power, so Learn and Live!

Do you have questions or comments for your doctor?

Take a few minutes to write your own questions for the next time you see your healthcare provider.

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The statistics in this sheet were up to date at publication. For the latest statistics, see the Heart Disease and Stroke Statistics Update at americanheart.org/statistics.