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What is a defibrillator?

When someone suffers a cardiac arrest, the heart stops. Blood is no longer being pumped around their body and without help, they will die.

If you see someone having a cardiac arrest, call 999, start chest compressions and get someone to find a defibrillator.

A defibrillator is a machine used to give an electric shock to restart a patient’s heart when they are in cardiac arrest.

You don’t need to be trained to use a defibrillator as it will give you clear instructions on what to do when you turn it on. The device checks the heart rhythm and will only tell you to shock if it’s needed.

We need more defibrillators

There are around 7,000 defibrillators in London on our database but if there were more, it would mean more people getting the life-saving shock as quickly as possible, giving them the best chance of survival.

The London Ambulance Service’s defibrillator accreditation scheme offers you formal guidance and support in buying, storing and using a defibrillator.

Learn more

A map comparing the availability of defibrillators in different London boroughs.

Watch this video to learn how to use a defibrillator.

Dr Fenella Wrigley, London Ambulance Service Chief Medical Officer

“When a cardiac arrest happens, every second counts and the key to survival is early chest compressions and early defibrillation.

“More public places need to have defibrillators. They are safe and simple to use and can significantly increase a person’s chances of survival.

“Making sure the public has easy access to defibrillators and the knowledge of basic life support skills will only help to save more lives.”

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