Defibrillators are a vital piece of medical equipment that should be accessible everywhere. A cardiac arrest can happen to anyone at any time, which is why having a defibrillator on hand and knowing how to use it can, quite literally, mean the difference between life and death for someone.

What are defibrillators?

Also known as automated external defibrillators (AEDs), they are portable, life-saving devices that have been designed to treat people experiencing sudden cardiac arrest. This is a critical medical condition in which the heart stops beating suddenly and unexpectedly.

How does a defibrillator work?

A defibrillator generates a powerful electrical current – about 300 joules of electrical energy – which is passed through the heart. This has the effect of stopping the uncontrolled trembling of the heart during a cardiac arrest and aims to reset a normal rhythm.

Rather than restart the heart, the device works to reset the natural pacemaker in our bodies to return the heart to normal function and rhythm.

AEDs are usually used alongside CPR to save the lives of those suffering cardiac arrest. CPR helps circulate the blood, keeping the heart and brain sufficiently oxygenated and the defibrillator is necessary to deliver the shock and hopefully return the heart to a viable rhythm.

Who can use defibrillators?

Defibrillators are designed so that everyone can use them, even with no first aid training. They are very easy to operate, with everything you need supplied with the defibrillator. They come with clear step-by-step spoken instructions that tell you exactly what you need to do in an emergency.

How do I use a defibrillator?

In the event of a suspected cardiac arrest, the first protocol is to dial 999 and request an ambulance. This way you can work on the patient knowing the paramedics are on their way.

1. Turn the defibrillator on by pressing the green button and following its instructions.
2. Remove clothing covering the patient’s chest.
3. Then, peel the plastic off the sticky pads and stick them onto the patient’s bare chest, as shown by the pictures on the defibrillator (usually one pad on the upper right side of the chest and the other pad on the lower left side of the chest, a few inches below the left armpit).
4. The defibrillator then analyses the patient’s heart rhythm. For the device to do this, you’ll need to stop administering CPR.
5. If it decides an electric shock is needed, you’ll need to press the shock button when instructed (or the defibrillator may do this automatically depending on the model). Ensure no one is touching the patient at this time. The defibrillator will then shock the patient’s heart.
6. When given the all-clear by the defibrillator, you’ll need to continue to administer CPR.
7. Continue until either the patient displays obvious signs of life, emergency services arrive, or until the defibrillator instructs you to stop so it can reanalyse the patient’s heart rhythm.

Who can a defibrillator be used on?

Defibrillators can be used on anyone over the age of one who is suffering from a cardiac arrest, however, for children under the age of eight, special paediatric sticker pads should be used.

An AED should not be used on a person who has a pacemaker fitted.