Special Considerations When Using an AED

An AED is a life-saving tool for individuals experiencing sudden cardiac arrest. An AED provides a powerful shock to restart the heart and help return it to a normal heart rhythm. Knowing when to use an AED is very important but, it is also equally as important to know when not to use an AED. 

What are Some Special Considerations when Using an AED

Before providing treatment to a victim of sudden cardiac arrest there are a few circumstances where special measures should be taken into account. When using an AED be sure to use the correct type of electrode pads for infants/children and adults to minimize any unnecessary injury. 

  • Avoid flammable vapors, solvents, fuel,  and areas as a spark from the AED could cause a fire
  • Do not touch the patient during the shock. Be sure to stand clear and ensure others are also in a safe area. 
  • Do not operate an AED in a moving vehicle 

Can You Use an AED on Someone with a Pacemaker?

Yes, if an individual experiencing sudden cardiac arrest has a pacemaker you can still use an AED to treat them, the pacemaker device is designed to withstand the shock of an AED. When using an AED on a victim with a pacemaker you should not place the electrode pads over the skin where the pacemaker was inserted. This can be identified typically by a raised lump on the right side of the chest just below the collarbone and about the size of a matchbox. Depending on the person, the device could be on the left side of the chest so be sure to check both sides. Don't forget to check children as well as they can also have pacemakers.

Can an AED be Used on a Pregnant Woman?

You can use an AED device on pregnant women without the fear of harming the pregnancy. The electrical shock of the device should not affect the fetus. Actually, it can be more dangerous not to use an AED on a pregnant woman experiencing sudden cardiac arrest. This is because a lack of oxygenated blood to the cells and organs of both the mother and the pregnancy can have negative effects. Getting the expecting mother's heartbeat back to a normal rhythm as quickly as possible is the most important aspect for both the mother and the pregnancy. 

Can You Use an AED on a Wet Person?

Sudden cardiac arrest can happen at any time anywhere, this includes pools, rainy or snowy days, and any other situations involving water. Since the AED provides an electrical shock this can cause issues when water is involved. Never use an AED submerged in water. If the individual is laying in water, move them away from the water or liquid to a dry place. If you find yourself in a situation where the victim is wet and needs assistance, remove their shirt and completely dry the chest before attaching the electrode pads. The AED can be potentially dangerous for both the victim and the user if the individual is wet.

Can You Use an AED if Someone has a Hairy Chest?

For the AED to work properly the electrode pads must fully connect to the patient's chest to analyze the heartbeat, heart rhythm, and potentially provide a shock. If the victim has a hairy chest you may need to remove the hair in order to properly place the AED pads as the hair can prevent the pad from coming into full contact. Many defibrillators come with a kit including a razor so you can quickly shave the victim's chest. If you are unable to find a razor, apply as much pressure to the electrode pads as necessary in order to get them as close to the victim's chest as possible. 

What Should You Avoid with a Defibrillator

Conscious and Breathing Normally

Typically, an AED should only be used if the individual is unconscious (not responsive) and is also not breathing correctly. There is a type of breathing called agonal breathing which can happen in these situations which are not considered normal breathing. It is vital to be able to identify the difference between agonal breathing and normal breathing. Agonal breathing can sound like gasping, shallow half-breathes, snoring, snorting, and labored breathing. If an individual is not experiencing agonal breathing and is conscious, it is not advised to use an AED. 


You should not use a defibrillator if the individual has a DNR or does not resuscitate. If you find the individual has a DNR bracelet or a tattoo that says do not resuscitate, you should follow the individual's wishes and respect the DNR and not use the AED. 

Heart Attack 

If the individual is having a heart attack you should not use a defibrillator. The heart issues from a heart attack differ from that of a sudden cardiac arrest. Sudden cardiac arrest is an electrical malfunction within the heart where with a heart attack there is a blockage in one of the arteries cutting off the supply of blood to the heart. Individuals experiencing a heart attack will be breathing and conscious, unlike sudden cardiac arrest where victims are unresponsive. An AED is not a treatment option for heart attacks and also has the potential to cause greater harm to the individual. 

Faulty or Expired AED 

Do not use a faulty AED on a person experiencing cardiac arrest. Make sure the AED is working properly and the green-ready light is showing. Check all parts of the AED like the electrode pads and batteries to ensure they are not expired. Do not use faulty, missing parts, or expired AEDs, call 911 and look for another functioning AED until help arrives. 

What Special Circumstance Should a Rescuer Consider

A rescuer should consider a wide variety of factors when using an AED during a sudden cardiac emergency. Victims should be in a safe, dry environment. It is safe to use an AED on a pregnant woman as well as individuals with pacemakers. Do not use an AED on victims experiencing a heart attack as it can cause more harm and will not fix the internal issue. Always ensure you have the correct pad size and fully operational AED. Time is the most critical factor during a sudden cardiac emergency. When you notice a cardiac emergency check to see 

  • Is the AED operational? 
  • Is the scene safe? ( no water or fire hazards) 
  • Does the person need an AED?
  • Do they require any special treatment? (infant, pacemakers, hair) 

Each situation is unique and knowing when not to use an AED is a vital piece of information in understanding and using automated external defibrillators.