Universal steps to operate an Automated External Defibrillator (AED)
Sudden Cardiac Arrest is when a person’s heart stops pumping blood suddenly and unexpectedly, and can occur anywhere. One of the things that bystanders can do to help someone who has suffered from a Sudden Cardiac Arrest is to use the American Heart Association’s Chain of Survival, starting with early access to EMS (calling 9-1-1), starting CPR as soon as possible after the cardiac arrest occurs, and using an Automated External Defibrillator (AED) as soon as possible.
An AED is a small computer-controlled device which will analyze a victim’s heart rhythm, and determine if it can be shocked to help restore a normal heart rhythm. Often, when a person suffers Sudden Cardiac Arrest, their heart is quivering instead of beating—a condition known as Ventricular Fibrillation—and the AED can recognize this. This condition can be stopped with an electrical shock. The AED is designed to be able to see if a victim’s heart is in Ventricular Fibrillation, and if so to deliver an appropriate shock to stop this condition.
All AEDs operate on simple, universal principles, which follow these steps (continue CPR while these steps occur, if possible):
- Power the device on. Usually, there is a button labelled “Power” or “On/Off,” and is usually green. Press this button to power the device on. Certain devices turn themselves on when the user opens the case.
- Place the pads on the bare chest of the victim. Always use the adult pads on an adult victim; if there are two sizes of pads, use the larger ones on an adult and the smaller ones on a child or infant. One pad goes on the victim’s upper right chest, and the other goes on the victim’s left side. The pads will have a diagram indicating which pad goes on what side.
- Plug in the pads connector. Most AED pads will have a connector that plugs into a socket on the AED; this socket is often marked and sometimes has a flashing light to show where they plug in. Certain models already have the pads connecter attached, and will not need to be plugged in separately.
- Take a pause; the AED will say “Analyzing heart rhythm, stand clear of patient” (or something very similar) when it is ready; at this point CPR should stop, and everyone should stand clear of the victim, while the AED reads the victim’s heart rhythm to see if it will benefit from being shocked by the AED. Some models of AED may have a separate button labelled “Analyze”; in this case, press the button and it will analyze the heart rhythm.
- The AED will then say either “Shock needed” or “No shock needed” (or something very similar). If it says “shock needed” it will start to charge, and then the button labelled “Shock” will flash and the machine will say to press the button; make sure to say “CLEAR” in a loud voice and look to make sure no one is touching the patient, then push the “Shock” button. There will be a contraction of some of the victim’s muscles. CPR should then be restarted immediately, starting with chest compressions.
- If the AED says “No shock needed,” immediately begin CPR, starting with chest compressions.
The AED will then start to keep track of the time, and will remind you when it is time for the next pause for a rhythm analysis (which will occur two minutes later). The pause-analyze-shock (if needed) sequence will recur every two minutes, and CPR should continue, along with the AED pause-analyze-shock (if needed) cycle until EMS arrives.