Yes, using an AED (automated external defibrillator) is a core component of first aid. Organizations like the American Red Cross and the American Heart Association teach AED use alongside CPR as a standard part of first aid training. AEDs are specifically designed for non-medical bystanders to operate during a cardiac emergency, and using one within the first few minutes of cardiac arrest can raise survival rates dramatically.
What an AED Does
An AED is a portable device that analyzes someone’s heart rhythm and delivers an electrical shock if needed. During sudden cardiac arrest, the heart often falls into a chaotic electrical pattern where it quivers instead of pumping blood. CPR keeps some blood moving to the brain and organs, but it usually can’t fix the underlying rhythm problem. The AED’s shock resets the heart’s electrical activity so it can resume a normal beat.
The device does the diagnostic work for you. It reads the heart’s rhythm through adhesive pads placed on the chest and only allows a shock if it detects a rhythm that defibrillation can correct. If the person’s heart doesn’t need a shock, the AED won’t deliver one, no matter how many times you press the button. This built-in safety feature is a major reason AEDs are considered appropriate for untrained or minimally trained users.
How Much AEDs Improve Survival
The survival numbers make a strong case for why AEDs belong in every first aid response. A 23-year study published in the Journal of the American Heart Association tracked outcomes in a community program where trained volunteers used public AEDs on cardiac arrest victims. Among patients whose hearts were in a shockable rhythm, those rescued by community volunteers with AEDs survived at a rate of 64.2%, compared to 20.9% for those who waited for emergency medical services.
Speed matters enormously. Volunteers who delivered a shock within 2 minutes of the emergency call saw a 75% survival rate. Even at the 6 to 9 minute mark, volunteer-rescued patients survived at 54%, compared to just 15% for those waiting on paramedics. After 10 minutes, the advantage largely disappeared, with both groups dropping to similar and much lower survival rates. Every minute without defibrillation reduces the odds, which is why having AEDs available in public spaces and knowing how to use them is so critical.
How to Use an AED
AEDs are built to guide you through the process with voice prompts. Here’s what to expect if you ever need to use one:
- Call for help first. Have someone dial 911 while you begin. If you’re alone, call before starting.
- Turn on the AED. Open the case and press the power button. The device will immediately start giving you spoken instructions.
- Expose the chest. Remove clothing covering the chest. If the skin is wet, wipe it dry.
- Place the pads. One pad goes on the upper right chest, the other on the lower left side, a few inches below the armpit. Diagrams on the pads show you exactly where.
- Let the AED analyze. Make sure nobody is touching the person. Say “Clear!” loudly, then let the device read the heart rhythm.
- Deliver a shock if prompted. Again, make sure nobody is touching the person. Say “Clear!” and press the shock button.
- Start CPR immediately after. Whether the AED delivers a shock or advises that no shock is needed, begin chest compressions right away.
If the AED’s pads might touch each other (on a small person, for instance), place one pad in the center of the chest and the other on the back between the shoulder blades.
Using an AED on Children
AEDs can be used on children ages 1 to 8 with pediatric pads, which deliver a lower energy dose appropriate for smaller bodies. For children 8 and older, or those weighing more than 55 pounds, standard adult pads are used. If a child under 8 goes into cardiac arrest and you only have adult pads, use them anyway. A shock with adult pads is better than no shock at all. For infants under 1 year, there isn’t strong enough evidence to recommend for or against AED use, but most guidelines suggest using one with pediatric pads if no other option exists.
Legal Protections for Bystanders
If you’re hesitating because you’re worried about getting sued, federal law in the United States provides broad protection. Under 42 U.S. Code § 238q, any person who uses or attempts to use an AED on someone experiencing a perceived medical emergency is immune from civil liability for any harm that results. This protection applies as long as you’re acting in good faith. It only falls away in cases of willful misconduct, gross negligence, or reckless indifference to the person’s safety.
This federal immunity is separate from state-level Good Samaritan laws, which add another layer of protection in most states. The legal framework is intentionally designed to encourage bystanders to act without fear, because the alternative (doing nothing) almost always results in death.
Maintaining an AED
If you own or manage an AED at a workplace, gym, school, or home, keeping it ready is straightforward but non-negotiable. Most electrode pads have a shelf life of 18 to 30 months, while batteries last 2 to 5 years on standby. Some models, like those from ZOLL, are designed for both pads and batteries to last up to 5 years, while Philips HeartStart pads typically last about 2 years with batteries lasting around 4. Pediatric pads often expire sooner than adult pads.
Most AEDs run a self-check and display a status indicator (usually a green light or checkmark) showing they’re ready. Get in the habit of glancing at this indicator regularly. When pads or batteries approach their expiration date, replace them before they expire. An AED that looks fine but has dead batteries or dried-out pads is useless when it counts.