How to Use an AED: A First Responder's Guide to Automated External Defibrillators

An Automated External Defibrillator — commonly known as an AED — is a portable device that analyzes the heart's rhythm and delivers an electrical shock to restore a normal heartbeat during sudden cardiac arrest. The American Heart Association reports that when an AED is used within the first few minutes of cardiac arrest, survival rates can exceed 70 percent. Yet many people walk past AEDs every day without knowing how to use them.

AEDs are everywhere. You can find them in airports, shopping malls, gyms, schools, office buildings, churches, and many public spaces. They are typically stored in wall-mounted cabinets marked with a green heart symbol or the letters "AED." In Florida, the Cardiac Arrest Survival Act encourages AED placement in public buildings and provides liability protection for good-faith users.

Step 1: Turn on the AED. Most devices activate when you open the lid or press a power button. The AED will immediately begin giving you clear voice prompts. Follow these instructions exactly — the device is designed to guide even a first-time user through the entire process.

Step 2: Expose the chest and attach the electrode pads. Remove or cut away clothing from the chest. Peel the backing off the adhesive pads and place them exactly as shown in the diagrams printed on the pads. One pad goes on the upper right chest below the collarbone. The other goes on the lower left side of the chest below the armpit. Press firmly to ensure good contact. If the chest is wet, dry it first. If the person has excessive chest hair, you may need to shave the area or press the pads down firmly.

Step 3: Let the AED analyze. The device will instruct everyone to stand clear while it analyzes the heart rhythm. Do not touch the person during analysis. The AED will determine whether a shockable rhythm is present — specifically ventricular fibrillation or pulseless ventricular tachycardia.

Step 4: Deliver the shock if advised. If the AED recommends a shock, it will charge automatically and instruct you to press the shock button. Loudly announce "Clear!" and visually confirm that no one is touching the victim before pressing the button. If no shock is advised, the AED will tell you to resume CPR immediately.

Step 5: Resume CPR immediately after the shock. Do not stop to check for a pulse. Begin 30 compressions followed by 2 breaths (or continuous compressions for Hands-Only CPR). The AED will re-analyze the rhythm every 2 minutes and prompt you if another shock is needed. Continue this cycle of CPR and AED analysis until EMS arrives. Our CPR and AED certification courses in Tallahassee provide hands-on practice with actual AED training devices so you feel confident using one in a real emergency.