An automated external defibrillator, or AED, is a portable device that can help a person in sudden cardiac arrest. Cardiac arrest means the heart has stopped pumping blood effectively, so the brain and body are not getting oxygen. Fast action matters because survival chances can drop by about 7% to 10% for every minute without CPR and defibrillation.
AEDs are designed so trained students, teachers, coaches, and bystanders can use them safely in an emergency.
Key Facts
- Call emergency services first, then get the AED and start CPR if the person is unresponsive and not breathing normally.
- AED = automated external defibrillator, a device that checks heart rhythm and gives a shock only if needed.
- CPR rate = 100 to 120 compressions per minute for high quality chest compressions.
- Survival chance can decrease by about 7% to 10% per minute without CPR and defibrillation.
- Pad placement: one pad on the upper right chest and one pad on the lower left side below the armpit.
- Safety rule: no one touches the person while the AED analyzes or shocks, because touching can interfere with the device and may be unsafe.
Vocabulary
- AED
- An AED is a portable device that analyzes a person's heart rhythm and can deliver an electric shock to help restore a usable rhythm.
- Cardiac arrest
- Cardiac arrest is when the heart suddenly stops pumping blood effectively to the body.
- Defibrillation
- Defibrillation is the delivery of a controlled electric shock to stop a dangerous heart rhythm so the heart can restart a normal rhythm.
- CPR
- CPR is cardiopulmonary resuscitation, a method of chest compressions and sometimes rescue breaths used to move blood and oxygen during cardiac arrest.
- Heart rhythm
- Heart rhythm is the pattern of electrical activity that controls how the heart beats.
Common Mistakes to Avoid
- Waiting to use the AED until a professional arrives is wrong because every minute without defibrillation lowers the chance of survival.
- Touching the person while the AED is analyzing or shocking is wrong because it can affect the rhythm reading and may put the rescuer at risk.
- Placing pads over clothing is wrong because the pads need direct contact with bare, dry skin to read the rhythm and deliver energy properly.
- Stopping CPR for a long time to set up the AED is wrong because chest compressions should be interrupted as little as possible.
Practice Questions
- 1 A person collapses at 2:00 p.m., and an AED shock is delivered at 2:06 p.m. If survival chance drops by about 8% per minute without defibrillation, estimate the total percentage drop in survival chance.
- 2 During CPR, you give 110 compressions per minute. How many compressions would you give in 2 minutes if you kept the same rate?
- 3 A student brings an AED while another student is doing CPR. Explain the correct order of actions from turning on the AED to resuming CPR after a shock or a no-shock message.