In the past, defibrillators were complicated and cumbersome. Only medical professionals with extensive training in heart rhythm interpretation could use them. The equipment was large, expensive and difficult to maintain. Today, defibrillators are automated, portable, affordable and easy to use. AEDs read heart rhythms and determine whether a shock should be delivered. In addition, AEDs have audio and visual prompts to guide users.
According to the American Heart Association (AHA) Public Access Defibrillation (PAD), which places AEDs in the hands of trained laypersons, has the potential to be the single greatest advance in the treatment of cardiac arrest since the development of CPR.
Survivors of Sudden Cardiac Arrest (SCA) usually have four things in common: Someone witnessed the event, recognized the emergency, decided to help, confirmed unresponsiveness and called 9-1-1 or the local emergency number; Someone started CPR immediately; Someone arrived quickly with a defibrillator to shock the heart back to a healthier rhythm; Professional Emergency Medical Services (EMS) personnel provided advanced life support, including airway and breathing support and medications.
When SCA occurs, most victims have an abnormal heart rhythm called VF. When the heart is in this state, it cannot beat in a coordinated fashion and blood does not circulate to the heart and the brain. First, the pulse stops. Then, breathing stops. The victim loses consciousness, collapses and appears lifeless. VF is a treatable rhythm. During VF electrical energy is present in the heart, but it is chaotic. If the heart can be shocked quickly with a defibrillator, a normal heart rhythm may be restored. This is called defibrillation.
SCA, by definition, is unexpected. It can happen to anyone, any time, regardless of age, race or gender. However, some people are at greater risk than others. Here are some factors that increase individual risk:
A-Men age 40 or older
C-High blood pressure
G-Personal history of heart disease
H-Family history of heart disease
When SCA occurs outside the hospital, it occurs most often in the home. For this reason, families of some at-risk individuals have elected to place AEDs in their homes and to be trained in CPR and AED use. Researchers are investigating whether or not home defibrillation will prove to be an effective and costeffective strategy for improving survival. Studies have identified locations that the following locations seem to have a higher incidence of SCA:
G-Large industrial sites
J-Physician offices (cardiology, internal medicine, family medicine)
M-Streets and highways
N-Trains and ferries
O-Urgent care centers