What Is a CPR AED?

AEDs, or automated external defibrillators, are portable devices that diagnose cardiac arrhythmia (ventricular tachycardia and ventricular fibrillation) in human beings. AEDs are designed for simple use by a layperson with little training; AEDs are normally accessible and clearly labeled in public spaces or establishments. There is a difference between AEDs and standard in-hospital defibrillators.

History

• The first available AEDs were the monophasic type, which generated shocks up to 400 joules. This high-energy shock, unfortunately, increased cardiac injury and burns to the bodies of patients. Newer AEDs use biphasic algorithms to provide two low-energy shocks between 100 and 200 joules. According to Zoll, this form of low-energy shock proved more efficient in tests and reduced complications and recovery times.

Function

• AEDs are used mainly for the two types of cardiac arrhythmia that lead to cardiac arrest: ventricular tachycardia, which is a dysfunctional and rapid heartbeat, and ventricular fibrillation, which is an abnormal contraction of cardiac muscles of the heart ventricles that prevents blood from pumping. The device automatically diagnoses the heart rhythm and informs the operator if a shock is necessary.

Significance

• AEDs, unlike hospital defibrillators, require little training. First aid, basic life support and CPR, or cardiopulmonary resuscitation, classes teach a layperson how to use the device. The fully operational and easy-to-use device allows a trained, non-medical professional to perform necessary life-saving procedures before an ambulance arrives. According to the American Heart Association, AEDs in the United States use electronic voiceover to guide the operator of the device.

Accessibility

• Publicly accessible AEDs are usually stored in brightly colored cases and placed in open areas of buildings. The devices are also normally held by trained personnel at events or public spaces such restaurants, airports, hotels and fitness centers. The American Heart Association explains that AEDs are the greatest advancement in publicly accessed treatment for cardiac arrest since CPR. The International Liaison Committee of Resuscitation developed a universally recognized sign for AEDs.

Misconceptions

• AEDs are not designed for treatment for flat-lined or asystolic patients. Those patients require CPR and a cardiac stimulant (a drug). Regular defibrillators require more extensive training; they are typically larger and are found only in clinics and hospitals. It is important to note that AEDs do have expiration dates, which are highly visible on the device.