It's the size of a laptop computer, weighs just a few pounds and can literally zap life back into someone who has collapsed in cardiac arrest. It's an automated external defibrillator, known as an AED.

AEDs can mean the difference between life and death for someone having a heart attack. If the heart stops, the AED can often get it pumping again. Each minute that treatment is delayed, a person's chance of survival drops by about 10 percent. Within just five minutes, brain damage can be permanent.

The AED delivers an electrical shock to the heart to restore a normal heart rhythm, which gets the blood flowing again. When used correctly, there is little danger of shock or injury to the person using the AED or to any bystanders.

You'll see AEDs in many public places, including airports, casinos, shopping malls, golf courses and sports stadiums.

Before using an AED, the American Heart Association (AHA) says several emergency actions need to be taken by a trained individual:

• Recognize the emergency as a cardiac arrest.
• Have someone call 9-1-1 right away to access the Emergency Medical System (EMS) and get the defibrillator if one is nearby. (If you are alone, call 9-1-1 and get the defibrillator yourself.)
• Begin CPR promptly. When CPR is done correctly, mouth-to-mouth breathing and chest compressions circulate blood (and oxygen) to vital organs. This buys time until defibrillation can be given.
• Use the AED as soon as it is available. Follow the instructions carefully.
• Continue CPR if instructed to do so until help arrives.

If you are an untrained bystander, and witness a sudden collapse of someone:

• Call 9-1-1- or tell someone else to call 9-1-1.
• Look for signs of life. Do not waste time checking for a pulse. Call loudly and if there is no response, gently shake the victim to see if they are conscious. If they do not respond, then check to see if they are breathing. If there is no breathing at all or just occasional gasping and the person is not responsive, then the person may be in cardiac arrest.
• The 9-1-1 dispatcher may give you instructions in continuous chest compressions while you wait for the EMS to arrive.

Both the AHA and the American Red Cross offer CPR and AED courses. The AHA's Heartsaver AED program includes training in both CPR and AED use and can be completed in three to four hours. To find out more about Heartsaver AED, call 877-AHA-4CPR (877-242-4277).

If you want to get an AED in your workplace, you will need to have a doctor write an order for one. And be sure that as many people as possible get trained in CPR and how to use the defibrillator.

It just might save a life!

Related Articles Breathing New Life Into CPR Automated External Defibrillator What Do You Know About CPR? Cardiopulmonary Resuscitation: Basic Information About CPR

External Sources American Heart Association. AED programs Q & A. . Accessed October 02, 2008 American Red Cross. Do you know your facts about CPR? . Accessed October 02, 2008 Ewy GA. New concepts of cardiopulmonary resuscitation for the lay public. Circulation. 2007;116:e566-e568.. Accessed October 02, 2008

This article was reviewed and updated 08-01-2009.