An AED (Automatic External Defibrillator) is essentially a computerized version of a defibrillator, a machine that transmits an electrical signal via electrodes placed on the patient’s chest to restore normal heart rhythm in the case of cardiac arrest.
Everyone in the nation probably remembers the 24 year-old football player, Damar Hamlin, who suffered cardiac arrest during a game in January .
Emergency medical personnel immediately responded by removing Hamlin’s helmet, placing him on oxygen and performing cardiopulmonary resuscitation for several minutes before transporting him to a local hospital.
Despite that the two phrases are used interchangably, there is a difference between cardiac arrest and a heart attack.
Cardiac Arrest is when the heart’s electrical system stops functioning properly.
AEDs are utilized to prevent or correct an arrhythmia, which is a heartbeat that is too fast or too slow .
Dangerously abnormal heart rhythms include “ventricular fibrillation” (rapid, uncoordinated heartbeat) and “ventricular tachycardia” (rapid heartbeat that keeps the heart from properly pumping blood). The patient typically becomes unresponsive or struggles to breathe.
If medical intervention does not take place, death will occur within a few minutes.
A heart attack is a medical condition generally caused by circulatory problems. Most heart attacks are caused by Coronary Artery Disease (CAD), which is the result of plaque that builds up in the walls of arteries that carry blood to the heart.
Chest pain, also called angina, is the most common CAD symptom. Other symptoms include pain or discomfort in the arms or shoulder, lightheadedness, nausea or cold sweats, weakness, and shortness of breath. Immediate medical intervention is crucial to preventing permanent damage to the heart or in the worst case scenario, preventing death.
During a heart attack, the heart is still beating but blood flow is impeded. A heart attack can, however, lead to cardiac arrest.
An AED will recognize ventricular fibrillation and ventricular tachycardia. Lack of oxygen in the heart will cause certain cells in the heart to begin to discharge electrical impulses as a way to increase circulation, which causes the heart to go into ventricular fibrillation. If the heart does not have enough oxygen, the heart will start beating faster, in an effort to increase circulation which in turn can result in ventricular tachycardia.
When an AED recognizes either of these two deadly rhythms, it will instruct the user to initiate a shock.
The AED shocks the heart to stop the unorganized or dangerously fast electrical activity to allow the heart to return to its normal electrical activity, thus pumping and thereby circulating oxygenated blood. Immediate intervention is critical. The longer the heart is not pumping blood, the more the heart muscle is damaged. Eventually, all electrical activity will cease, this condition is called asystole or “flatlining.” According to the FDA, ”The probability of survival decreases by 7% to 10% for every minute that a victim stays in a life-threatening arrhythmia.”
A common misconception about defibrillation is that defibrillators “jump start” a heart that has completely stopped. Once the heart has stopped all electrical activity, a defibrillator will not restore the normal rhythm.
AVIVE, one of the most prominent manufacturers of AED machines, says you should only use an AED on a person if their heart suddenly stops beating, or if they experiencing sudden cardiac arrest. Symptoms are immediate and drastic and include no breathing, or gasping noises paired with abnormal breathing, unresponsiveness, unconsciousness, and no pulse.
If you encounter someone with these symptoms, call 911, designate someone to search for a defibrillator, and immediately begin CPR.
There are case when NOT to use a defibrillator. Which are various special circumstances that require extra care when determining if and how to use an AED. All AED units have their own intended use statements, so it is recommend all AED owners review their unit’s requirements.
The victim Is conscious and breathing normally—If the person is conscious and breathing normally, they do not require an AED shock. Generally speaking, an AED should be used when a person is unconscious (not responsive) and not breathing properly. It is important to know that sometimes victims of sudden cardiac arrest in this state may demonstrate agonal breathing for seconds to minutes after their heart has stopped beating. Agonal breathing is NOT normal breathing. It is crucial that you do not mistake agonal breathing for real breathing. Agonal respirations can sound like gasping, snorting, strange, shallow half-breaths, or possibly moaning.
If the patient is having a heart attack they will be breathing and conscious, in these cases an AED is not needed to restart the heart. Victims of cardiac arrest, however, will suddenly become unconscious and collapse. They will be unresponsive and not breathing or breathing agonally (abnormally). Unlike cardiac arrest, which always happens suddenly, a heart attack can be sudden or may develop over time. If someone is experiencing a heart attack, immediately call 911.”
For more information about AEDs,including training go to: cpr.heart.org.
