When a person is undergoing cardiac arrest a prompt and effective response can really make the difference between life and death. One of the most effective ways to help is to deploy an Automated External Defibrillator, or AED.

An AED is designed to shock the heart back into a normal rhythm and get it pumping blood correctly again. They operate in the same way as the defibrillators you see on TV, however they are designed to be used by people with little or even no medical training.

As straightforward as they are to use, sometimes you can be presented with something a little out of the ordinary. An example of one of these curveballs is when the person experiencing cardiac arrest has been fitted with a pacemaker.

So, can you use an AED on someone with a Pacemaker?

Short Answer – Yes!

Well actually no. Bear with us!

Most AED instructions will tell you not to shock someone who has a pacemaker. This is because a pacemaker kind of functions like a mini AED already. They are designed to be installed into a patient who has a slow heart beat. They monitor the patient's heartbeat and will help their heart return to a normal rhythm if they detect signs of abnormality. Like the AED, they do this by using electrical impulses.

The problem comes when the pacemaker fails entirely, or when it is working but is unable to restore an effective rhythm. This is because the pacemaker is not designed to tackle fibrillation, which is the medical word for the quivering tremor that the heart experiences when its electrical impulses fail and it can no longer pump.

Fibrillation is very different to the arrhythmia that pacemakers are designed to deal with. Pacemakers simply do not have the power capacity to deliver the level of voltage required to shock the heart out of fibrillation and back into a normal, healthy rhythm.

Can You Tell If a Person Has a Pacemaker?

Unfortunately, if you come across a stranger who has collapsed, it is hard to tell if they have a pacemaker fitted. For one thing, one of the symptoms of cardiac arrest is that the patient is unconscious and unresponsive, so it’s not as if they can tell you!

As you remove layers to expose the skin to attach the AED electrode pads, you should keep an eye out for operation scars or the telltale bulge of the pacemaker itself, which can normally be found on the upper left chest toward the collarbone.

In general though, wasting time looking for signs the person has a pacemaker will do more to harm their chances of survival.

How to Use an AED on a Person With a Pacemaker

If you know that the person you are working to save has had a pacemaker installed, then there are some steps you can take during the use of the defibrillator.

The most important is to try to avoid placing the defibrillator pads directly over the pacemaker. As we mentioned above, the pacemaker should be visible under the skin as a small coin shape usually found beneath the left collarbone. Even if you can’t see it, you should be able to feel it by running your hand over the area.

Follow the AED’s instructions to attach the electrode pads to the patient. However, try to avoid placing any pad within an inch of the pacemaker. If at all possible, try to attach the electrode pads as far from the pacemaker as possible whilst still adhering to the instructions as issued by the AED.

Can the Pacemaker Be Damaged?

Yes, it the pacemaker can get damaged, though the further you keep the pads away from it the better the chances are that it will survive undamaged. Frankly though, there is a good chance that it will be damaged no matter what you do. When a patient with a pacemaker is shocked by a medical professional they will dial down the defibrillator to the very lowest setting they can to try to avoid damage.

When a normal person uses an AED, however, it is not normally possible to alter the voltage on these devices. After all, they are designed to be as simple to use as possible, and setting the appropriate voltage is beyond the ability of non-professionals.

Nonetheless, this should not stop you using an AED on a person with a pacemaker. Yes, they may need to have it repaired or replaced at a later date, but because of your actions with the AED, at least they will be alive to worry about their pacemaker!

Should I Use an AED on a Person With a Pacemaker?

When you weigh up all the options and outcomes, it certainly does make sense to use an AED on a person experiencing cardiac arrest, even if they do have a pacemaker. This is down to the simple fact that prompt use of CPR and the AED simply gives the very best chance of survival.