If you’re in an emergency situation and you need instructions quickly:
- Click here for step-by-step instructions on how to use an AED on an adult
- Click here for step-by-step instructions on how to use an AED on a child
If you’re just curious or you’re brushing up on your knowledge, read our full guide below.
Automated external defibrillators (AEDs) are designed to be user-friendly; with just a few simple steps, you can potentially save the life of someone who has gone into sudden cardiac arrest.
Because AEDs are commonly kept in homes, offices, churches, and other locations devoid of trained medical personnel, they’re equipped with streamlined operations and easy-to-follow instructions. That’s the good news. While anybody can use one of these lifesaving devices, there’s still a bit of a learning curve, especially when you consider that every AED operates differently.
When to Use an AED
The first step is to determine whether an automated external defibrillator is actually needed. An automated external defibrillator should only be used on someone who is suffering sudden cardiac arrest (SCA). A person suffering SCA will be unconscious and not breathing, or only breathing in gasps. An AED should never be used on a patient who is having a heart attack and is still conscious and breathing normally. We cover the differences between these two conditions in our article contrasting cardiac arrest and heart attack.
Cardiac arrest victims will be unresponsive and not breathing or just gasping (in the case of agonal respirations). To determine whether you need a defibrillator:
- Shout their name and ask for a response, while gently shaking the victim.
- Check for signs of breathing. Administer CPR and defibrillation only if they are unresponsive and not breathing normally.
For more details, see our comprehensive guide detailing when not to use a defibrillator.
How to Use an AED
Do the following if someone is in cardiac arrest:
1. CALL: If You Identify an SCA Victim, Call 9-1-1
If someone goes into cardiac arrest, call emergency services immediately. If multiple bystanders are available, have someone else call 9-1-1 and retrieve a defibrillator while you perform CPR. During cardiac arrest, the heart does not pump blood to the other organs, so organ failure can occur in just minutes. That’s why it’s important to start emergency intervention immediately while someone else calls for help. Cerebral injury is likely to occur after five minutes without blood flow to the brain. Every minute is critical.
If nobody else is around, call 9-1-1 and turn on the AED. Consider putting the dispatch on speakerphone so that you can communicate while administering treatment.
2. PUSH: Perform CPR While Waiting for an AED
If someone else is running to retrieve the defibrillator, start CPR immediately. If you have not received full CPR training, give hands-only CPR with chest compressions and no rescue breaths.
Push down firmly on the center of the chest with both hands at a rate of 100 to 120 beats per minute. Push to a depth of 2 to 2.4 inches. The chest should fully recoil between each compression. If you’re not sure about the speed, just follow the beat of the Bee Gees’ Stayin’ Alive.
As soon as the defibrillator is available, stop administering CPR and follow the device procedures below.
3. SHOCK: Deploy the AED
Automated external defibrillators are designed to guide laypeople through the entire process of delivering a shock with little to no prior knowledge required. Follow these steps to deploy the AED.
How to Use an AED on an Adult
If you’re in an emergency situation and you need quick instructions, here are the steps for using an AED:
- Confirm that the patient is experiencing cardiac arrest (not breathing normally, unconscious).
- Turn on the AED. This is achieved by lifting the lid and/or pressing an “On” button.
- Expose the patient’s chest (this includes removing bras) and attach the pads to their bare skin. Use the diagram on each pad as a guide.
- Connect the pads to the defibrillator if they are not already connected.
- Stand clear of the patient while the AED analyzes the patient’s heart rhythm.
- Follow the voice prompts. Press the “Shock” button if the AED determines that the patient has a shockable rhythm. For automatic AED models, the AED will shock the patient automatically.
- When the shock is complete (or if a shock is not recommended), perform CPR until emergency services arrive or the patient regains consciousness.
- After 2 minutes of CPR, the AED may again prompt you to stop CPR to analyze the patient’s heart, potentially resulting in additional shocks. Continue to follow the AED prompts, with 2 minutes of CPR between each analysis, until emergency services arrive.
If you’re just brushing up on your training and would like a more thorough explanation, refer to the sections below.
Turn on the Device
This is accomplished either by lifting the lid or by pressing an “On” button. The “On” button will often be green in color and contain the I/O symbol (the Philips HeartStart OnSite is one example). As soon as the device turns on, the audible and/or visual instructions will begin automatically.
Check for Readiness
All AEDs, like the Cardiac Science Powerheart G5, are equipped with a readiness light confirming that the device is operational. Some devices will also provide audible warnings if there’s a problem with the battery, pads, or internal components.
Because defibrillators perform daily, weekly, and monthly self-tests (and alert users of problems accordingly), you shouldn’t encounter any unexpected usability issues. In the unlikely event that the device does report a problem, do not use the device. Just perform CPR until emergency services arrive.
Apply the Electrode Pads
Proper AED pad placement isn’t only important for ensuring the electric shock is effective; it also allows the AED to assess the patient’s progress throughout the treatment.
Expose the patient’s bare chest, remove any medication patches, and apply the pads to the skin. Use the visual diagram on each pad as a guide for placement: one pad goes below the collarbone on the upper-right side of the chest, and the other pad goes on the lower-left side of the chest wall.
If the patient has a pacemaker, you’ll need to place the patch about two inches away from the implant. Do not place an electrode pad directly over a pacemaker.
Push down firmly on each pad so that the bonding agent adheres to the skin. If the patient has an especially hairy chest and the pads don’t stick properly, you may need to shave the area. If no razor is available, strong tape may be used to pull the hair away from the skin.
The cables should already be connected to the defibrillator, but if they are not, you’ll need to plug them in before proceeding.
Before administering a shock, remove your hands from the patient’s skin and stand clear. Advise any onlookers to stand clear as well. Because a defibrillator transmits live electricity to the patient’s heart, no one must touch the patient’s skin during this crucial time. Also, take a moment to ensure that no part of the patient’s body is submerged in water.
Administer a Shock if Necessary
AEDs are available in both automatic and semi-automatic varieties:
- A semi-automatic device will scan for a shockable rhythm and then instruct you to “Administer shock” or to press the “Shock” button. This is usually a red or dark-colored button with a lightning bolt or a heart. Press the button if and when instructed to do so. The device will then shock the patient’s heart and analyze the response to determine if additional shocks are needed. Continue to press the button only if instructed to do so.
As a safeguard, AEDs only ‘activate’ the shock button when a shock is advised. Due to this protection, it is not possible for lay rescuers to ‘accidentally’ shock a patient who should not be shocked. This is a comforting feature for non-trained responders and is just one of many ways in which AEDs are built intuitively and safely for laypeople to use.
- A fully automatic device will analyze the patient’s heart rhythm and then deliver a shock automatically without intervention from the user. If your defibrillator is automatic, you’ll be instructed to stand clear and then notified as shocks are administered. All you have to do is wait and assess the patient’s response, resuming CPR immediately after the shock is delivered.
In some cases, the device will tell you not to shock the patient. There are four main types of heart rhythms that occur when the heart stops beating. Of those four rhythms, only two are AED shockable rhythms. If your AED says “No shock advised” or something similar, just proceed to the next step, and continue CPR.
When the device confirms that no additional shocks are recommended (or that no shocks are recommended to begin with), take a moment to assess the patient. If they are now conscious and breathing, remove the AED pads and stay with them until emergency medical responders arrive.
If the patient remains unconscious and unresponsive, it’s time to return to CPR. At this point, it’s okay to touch the patient again. The assessment has concluded and no electricity is being delivered to the heart. Resume chest compressions, but do not turn off the AED or remove the pads. If the device provides additional instructions, be sure to do as prompted. As long as you keep the chest compressions going until help arrives, and continue to follow the prompts of the AED, the patient will maintain the best possible chance of survival.
How to Use an AED on a Child
Automated external defibrillator adult pads are configured for use on patients over 8 years of age and over 55 pounds, but they can be used on patients of all ages.
If child pads are available alongside the defibrillator, they should be utilized for child patients under 8 years old or less than 55 pounds. If no child pads are available, then the AED should still be used with the pre-connected adult pads. Some AEDs, like the Physio-Control Lifepak CR2, have a child button that allows you to adjust the instruction and voltage at the touch of a button. If your AED has a child button, child key, or separate child pads, make the necessary adjustments immediately.
When administering CPR to a child victim, the above steps are still applicable, but two important modifications should be made:
- Pad placement: For small children, one pad should be placed in the center of the chest while the other pad is placed in the center of the patient’s upper back.
- Chest compressions: For older children and adults, you can compress the chest to a full 2.4 inches (6 centimeters). But for children under 8 years old and under 55 pounds, you should compress the chest approximately ⅓ of the depth of the chest, to no more than 2 inches (5 centimeters).
For a quick overview, here’s how to use an AED on a child:
- Confirm that the patient is experiencing cardiac arrest (not breathing normally, unconscious).
- Turn on the AED by pressing the “On” button and/or opening the lid.
- Press the child button, insert the child key, or attach the pediatric pads if available.
- Remove the child’s shirt and apply one pad to the center of the chest and one to the center of the upper back.
- Stand clear of the patient while the device analyzes their heart rhythm.
- Follow the audible instructions provided by the AED and press the “Shock” button only if prompted to do so.
- Perform CPR chest compressions until help arrives or the patient regains consciousness. Push down on the chest to ⅓ depth of the chest, no more than 2 inches (5 centimeters).
Can You Get in Trouble for Using an AED?
The prospect of using an automated external defibrillator can be intimidating. After all, you’re a civilian attempting to use a major medical device on an unconscious patient. If the patient dies, there’s the understandable concern that you may be held liable in some way.
The good news is that there are extremely strong protections in place for lay rescuers. As long as you do your due diligence and determine that the patient is suffering cardiac arrest, you shouldn’t be held liable for any outcomes under normal circumstances. Good Samaritan laws protect people who provide emergency assistance to those in need.
In addition, as long as you follow the audible guidance provided by the AED, you won’t inappropriately harm the patient. You will only be advised to deliver a shock if the device determines that a shockable rhythm is present, and AEDs are built in such a way that there is no way to accidentally deliver a shock to a patient who doesn’t need one. Nobody is asking you to play doctor. So just relax, follow the instructions provided, and stay with the patient until emergency services arrive.
How to Use an AED – A Quick Recap
Out-of-hospital cardiac arrest affects over 356,000 Americans every year. When used quickly and properly, an automated external defibrillator more than doubles the patient’s chance of survival to hospital discharge, especially if administered within the first minutes after the patient’s collapse. If you find yourself in the position of having to use one of these devices, just remember the following:
- Stay calm.
- Have someone call 9-1-1 immediately.
- Confirm that the patient is unconscious and not breathing normally.
- Turn on the device.
- Follow all AED instructions as the device talks you through the process.
- If the device fails to revive the patient, continue performing CPR until help arrives.
If you encounter a cardiac arrest sufferer and no AED is available, just perform chest compressions until help arrives. The whole process should only take five to 10 minutes, but those few precious minutes make all the difference in the world.