What is an automated external defibrillator (AED)?
An AED is a device about the size of a laptop computer
that analyzes the heart's rhythm for any abnormalities
and, if necessary, directs the rescuer to deliver an electrical
shock to the victim. This shock, called defibrillation,
may help the heart to reestablish an effective rhythm
of its own.
How does an AED work?
An AED is easy to operate. It uses voice prompts to instruct
the rescuer. Once the machine is turned on, the rescuer
will be prompted to apply two electrodes provided with
the AED to the victim's chest. Once applied, the AED will
begin to monitor the victim's heart rhythm. If a "shockable"
rhythm is detected, the machine will charge itself and
instruct the rescuer to stand clear of the victim and
to press the shock button.
If an AED is so easy to use, why do I need training?
Training is necessary in order to understand the role
of defibrillation in the broader context of the cardiac
chain of survival. Training in CPR and AED skills will
enable the rescuer to use all the steps in the cardiac
chain of survival, thereby significantly increasing the
victim's chance of survival.
How can I get trained in the use of an AED?
Contact your American Red Cross AT 865-584-2999
for a listing of training classes. The Red Cross
offers half-day courses that include CPR and AED skills
and comprehensive, daylong sessions that also include
first aid. These interactive courses are taught by certified
Red Cross instructors and use hands-on practice scenarios
and videos that reflect a variety of situations. Each
participant receives a skills card for use during in-class
practice sessions. The skills cards can also aid in retaining
skills after completing the course and serves as a quick
reference tool in an emergency.
Who can use an AED?
In most cases, EMTs and first responders (police and firefighters)
are required to know how to use an AED as part of their
job responsibilities. Furthermore, all 50 states now have
AED Good Samaritan provisions that help protect laypersons.
Contact your local or state emergency medical services
("EMS") department to find out about Good Samaritan protections
that your state provides for users of AEDs.
Where can I find AEDs?
AEDs can be found in corporate offices, shopping malls,
airports, sports stadiums, schools, community centers,
and other places where large groups of people gather and
the risk of a sudden cardiac arrest incident is very likely.
The number of devices in the community will continue to
grow as more and more people begin to understand the importance
of AEDs and AED training.
How can I buy an AED?
A physician's prescription is needed in order to purchase
most AEDs. This means that the medical director of a facility
or a physician used by such facility must prescribe and
oversee the AED program at any workplace or other facility
that houses an AED. Some AEDs can be purchased over the
counter without a prescription. GET
MORE INFORMATION ON PURCHASING AN AED (PDF).
What is sudden cardiac arrest (SCA)?
Sudden cardiac arrest cases are usually due to abnormal
heart rhythms called arrhythmias, the vast majority of
which are ventricular fibrillation. Ventricular fibrillation
is a condition in which the heart's electrical impulses
suddenly become chaotic, causing the heart to cease pumping
blood effectively. Victims of SCA collapse and quickly
lose consciousness, often without warning. Unless a normal
heart rhythm is restored, death will follow within a matter
of minutes.
The cause of sudden cardiac arrest is not well understood.
Many victims have no history of heart disease, or if heart
disease is present, it has not functionally impaired them.
Unlike a heart attack, which is the death of muscle tissue
from loss of blood supply, many victims of SCA have no
prior symptoms. SCA can strike anyone, at any time, anywhere.
How common is SCA and who is at risk?
SCA is one of the leading causes of death in the United
States. It strikes more than 200,000 Americans each year:
nearly one death every two minutes.
What is the current treatment for sudden cardiac
arrest?
The cardiac chain of survival is the current treatment
for sudden cardiac arrest.
What is the cardiac chain of survival?
The cardiac chain of survival is a series of four critical
steps. All four steps of the chain must be present to
help ensure survival from sudden cardiac arrest. The four
steps are:
- Step one: Early access to care (calling 9-1-1 or another
emergency number)
- Step two: Early cardiopulmonary resuscitation (CPR)
- Step three: Early defibrillation
- Step four: Early advanced cardiac life support, as
needed
The third step, delivering an electrical shock to the
heart, which is known as defibrillation, is recognized
as the most critical step in restoring cardiac rhythm
and resuscitating a victim of SCA.
