Cardiac arrest: could you help save someone’s life?

If someone has a cardiac arrest – which is when the heart suddenly stops beating unexpectedly – the sooner they’re treated, the better their chances of surviving. In fact according to the British Heart Foundation, after a cardiac arrest every minute without CPR and defibrillation reduces someone’s chance of survival by 10 percent


Yet a study led by the University of Warwick suggests people are reluctant to use public access defibrillators to treat cardiac arrests – and that many don’t even know what an automated external defibrillator (AED) is or how to use one.

“Public access defibrillation is very effective in certain cases of cardiac arrest outside of hospital,” says Gavin Perkins, Professor in Critical Care Medicine at Warwick Medical School.

“A study conducted in the US showed that the chance of survival was nearly double in the group that received CPR and were treated with a public access defibrillator compared with the group that received CPR alone. However the number of cases when a public access defibrillator is used is very low – just 0.15 – 4.3 percent of cardiac arrests that occur outside of hospitals.”

What are AEDs?

A defibrillator is a machine that gives a high-energy electric shock to the heart through the chest wall to someone who is in cardiac arrest. This high-energy shock is called defibrillation.

If you come across someone who’s had a cardiac arrest, start CPR. Here’s what you should do:

Step 1: shake the affected person’s shoulders gently and ask them if they’re alright. Then shout for help – if someone’s nearby, ask them to stay as you may need them.

Step 2: check for normal breathing. If someone’s in cardiac arrest, they won’t be breathing normally or at all, and they won’t be conscious. Look, listen and feel for normal breathing for no more than 10 seconds. If their breathing isn’t normal, open their airway by gently tilting their head back with one hand and lifting their chin with two fingers of your under hand.

Step 3: call 999

Step 4: give 30 chest compressions using the heel of one hand in the centre of their chest and the other hand on top of the first (interlock your fingers). Press down firmly and smoothly so that the chest is depressed by 5 – 6cm, and keep pressing at a rate of 100 – 120 compressions per minute (around two per second).

Step 5: give two rescue breaths if you’ve had first-aid training. If you haven’t, skip this step an>d keep performing hands-only CPR.

Step 6: repeat until the ambulance arrives or until the person starts to show signs that they’re regaining consciousness.

In the meantime, send someone to find the nearest defibrillator (when you call 999 the operator can tell you if there’s one nearby). Public access defibrillators are often found in places such as train stations, shopping centres, airport and leisure centres, and are designed to be used by anybody in an emergency. You don’t need training to use one, as the machines give spoken instructions. The defibrillator detects the heart’s rhythm and won’t deliver a shock unless one is needed. It will also tell you to resume CPR, if necessary.

Find out more about giving CPR by watching the demonstration video on the British Heart Foundation’s website. The website also has a video that shows how to use a defibrillator that’s well worth a look. After all, you never know when you may come across someone in cardiac arrest, and it could help you to save their life.

You can also find out where the nearest public access defibrillator is in your area by visiting the Heart Safe website.

World Heart Day is on September 29, 2017. Take the Heart IQ test at to find out how heart smart you are.