An automated external defibrillator (AED) is an essential first aid device that safely administers an electrical shock to a sudden cardiac arrest victim.

The AED automatically analyzes the heart’s rhythm. Then, if it senses that there’s no or an irregular rhythm, it will deliver an electric shock that will restore the heart to its normal rhythm.

However, for the victim to survive, you should place the AED pads correctly.

In this article, we’ll teach you the correct placement of AED pads so they can be as effective as possible.

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AED Pad Placement: An Overview

When you think of defibrillator pads, you wouldn’t be wrong to imagine them placed on a person’s bare chest.

But there’s more to the pads than just placing them on a person’s chest and giving them an electric shock.

In fact, a common mistake is to put the AED pad right on top of the victim’s heart.

Why Does the Correct Defibrillator Pad Placement Matter?

Simply put, placing AED pads the wrong way will make the electric shocks less effective.

Sometimes, the wrong AED pad placement can even be dangerous — such as when dealing with someone fitted with a pacemaker or who has metal jewellery on.

Though there’s a default position for the pads, some situations call for special steps or different ways of positioning.

Anterior Posterior Pad Placement & Anterior Lateral Pad Placement

Anterior-posterior and anterior lateral are the two basic positions of AED pad placement.

Anterior-posterior placement is also known as front-back pad placement. As the name implies, one pad is placed in front while the other pad is at the back.

For an adult patient, one pad should be put on the left side of the chest, just below the left nipple. Then the other one should be placed on the left side of the back, directly below the wing bone (or scapula).

Meanwhile, with anterior lateral pad placement, place the first pad on the right side of the chest below the collar bone but above the right nipple. Then put the second pad on the lower part of the left chest wall.

Alternatively, that second pad could be put over the left side of the ribcage, a few inches below the left armpit.

The only exception to these guidelines is when dealing with children or infants.

Generally, you can put the defibrillation pad in the middle of the chest and back. Because they’re smaller, their heart doesn’t really need as much direct charge to start beating again.

Where on the Chest Should the Defibrillator Pads Be Applied?

Automated external defibrillator pads come with a user manual. Most AEDs also come with visual instructions on the pads themselves.

Below, we’ll show you the proper AED pad placement for most cases:


Adults will have an anterior lateral placement for their AED pads.

This is the DEFAULT position for placing AED pads, so you should apply them as such unless you’re dealing with children or special cases (which we’ll also discuss below).

defib pad placement on an adult

Pregnant Women

It’s perfectly safe to use AED electrode pads on pregnant women. The AED pad placement is the same as with other adults.

But women — whether pregnant or not — should have the AED pads placed underneath the breast for the best chance for defibrillation to succeed.

defib pad placement on a pregnant female


For child cardiac arrest victims that are one to eight years old OR adults who weigh less than 25kg, you should use pediatric pads rather than adult pads.

Put one AED pad in the middle of the child’s chest wall, then put the other pad in the middle of their upper back.

Make sure to use the child setting, so the energy is adjusted for a younger patient.

If the AED doesn’t have a child setting, it’s better to still use the adult AED setting than do nothing. But since adult pads are bigger, just make sure they don’t touch when you put them on the child.

AED pad placement on a child


What applies to children also applies to infants.

However, spotting a sudden cardiac arrest in infants can be tricky since it can be mistaken for choking.

Cardiac arrest in infants is actually most likely caused by a blockage in the area rather than an actual heart problem.

If you see the baby visibly choking, first aid measures for choking apply first.

But if they aren’t clearly choking and you can’t feel a pulse, using an AED is your best bet — even if the initial cause of it was choking.

AED pad placement on a baby

Cardiac Arrest Victims With a Pacemaker

Pacemakers help the body maintain a normal heart rhythm. They’re very helpful for treating arrhythmia, but they don’t regulate the heart’s fibrillation.

It’s also very safe to use AED pads on sudden cardiac arrest victims with pacemakers — although you’ll need to be a bit more careful.

The first thing you should do is find out where the pacemaker is placed.

It’s usually in the upper left side of the chest. If that’s the case, then anterolateral placement is fine.

But if the pacemaker is in the upper right side of the chest, you should place the first pad at least an inch below or to the side of the device. You can place the second pad as is — at the lower part of the left chest wall.

AED pad positioning

Special Cases

The instructions provided are easy to understand and follow, but there may be special circumstances that will also call for extra consideration.

We’ve also included some common concerns that actually aren’t problems.


You shouldn’t be worried about putting AED electrode pads over tattoos since they won’t have an effect on the electrical shock.


The AED pads must not come into contact with anything metallic. After all, metals conduct electricity, and they might cause problems.

Be especially aware of jewellery on the upper body — such as nipple piercings, necklaces, and earrings.

You don’t necessarily have to remove them. Just ensure that they’re at least an inch from the electrode pads.

In RARE cases, it might be necessary to rip out the metal jewellery to safely and properly administer an AED shock.

If you don’t want to rip out the metal from the victim’s chest or upper body in general, you can opt for the anterior-posterior position for the defibrillation pads.

Large Breasts

For cardiac arrest patients with big breasts (whether male or female), simply lift the breast tissue and place the AED pad underneath it.


Scar tissue WON’T interfere with an AED shock — even if they were the result of surgery.

Besides, scars from surgery are usually not in the same anatomical position as the required AED pad placement.

Hairy Chest

AED pads need to have direct contact with bare skin — and having chest hair can reduce the contact. That can lower the chance of successful defibrillation and even cause a risk of burns.

So, having excessive chest hair can be very dangerous.

AEDs tend to come with a small razor so you can shave the victim’s chest. You can remove just enough for the right defibrillator pad placement.

Wet Patient/Chest

Water and electricity should NOT mix.

Place the patient somewhere dry, remove any wet clothing, and dry their chest thoroughly before putting the two pads.

Medicated Patch

You shouldn’t put AED pads on top of medicated patches since the electrical current won’t be as effective.

Wear gloves and carefully remove the patch. Then, wipe that area with alcohol.

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Frequently Asked Questions

Knowing how to properly apply AED pads on a cardiac arrest victim is certainly important.

Below, we’ve answered a few questions that can further help you in using AEDs.

Do You Need a Medical Background to Use the AED Machine?

No, you don’t need to have a medical background (or even advanced medical knowledge) to use an automated external defibrillator.

AEDs are actually designed so people with NO medical training can use them.

However, it’s still advised that people know the basic steps of first aid — particularly AED-use and CPR.

The AED pads also come with pictures, and the kit itself has audio prompts that are easy to follow.

Will I Still Need to Learn CPR?

Yes, CPR and AED-use go hand-in-hand.

CPR will mostly keep the blood pumping when the victim’s heart muscle stops. This is so that your other vital organs still continue to receive oxygen.

It’s possible to revive someone using CPR. However, AED is made to shock the heart muscle into starting again.

If you’re helping a cardiac arrest victim and can’t get an AED in the next three minutes, you’ll have to continue CPR.

But if an AED is readily available, administering an electrical shock should be your priority.

Are AED Pads Reusable?

No, for the sake of hygiene, electrode pads are not reusable.

You should also consider the pads used even if you put them on a person’s chest and didn’t administer a shock.

Can I Still Use Expired AED Pads?

No, you shouldn’t use expired AED pads.

The expiration dates differ per manufacturer, so check them well. AED pads usually have a life expectancy of 15 to 30 months — although some can have a shelf life of up to four years.

You can’t use expired pads since the gel around the edges will corrode, making them less effective.

Some problems you can encounter when you attempt to use them are:

  • The gel won’t stick to the victim’s body
  • The gel won’t conduct the current well
  • The electrodes will detach from the pads

How Should I Position the Patient When Using an AED?

The victim should first be in the correct anatomical position.

Anatomical position refers to the body’s NORMAL posture.

Basically, this means the person should be flat on their back, palms and toes facing forward, arms and legs not touching each other or the torso.

anatomical position


Correct AED pad placement is VITAL to a cardiac arrest victim’s survival.

AED kits have visual diagrams and auditory cues so that people with no medical training can also quickly operate them.

While AEDs are certainly life-saving, CPR is still an important first aid skill to learn.

That’s because if an AED is not available in the next three minutes, you’ll need to try to keep the heart pumping until help arrives.

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