Cardiac Arrest and how to use a defibrillator

How to use a defibrillator.

Example of a cardiac arrest and what to do.

St Johns Ambulance Information on understanding cardiac arrest and what you should do. Click here to go to their page or carry on reading for the information.

Cardiac arrest: COVID-19 update

If someone has become unresponsive and they are not breathing normally, they could be in cardiac arrest. Find out what to look for and what to do, including how to do CPR and using a defibrillator.

What is a cardiac arrest?

A cardiac arrest happens when someone’s heart stops.

If someone has become unresponsive and they are not breathing normally, they could be in cardiac arrest and you need to act quickly. Call 999 or 112 for emergency help and start CPR, using a defibrillator if available.

Signs and symptoms

If someone has a cardiac arrest, they may:

• be unresponsive
• be not breathing normally
• show no movement or signs of life. 

Simples - What to do

Detailed - What to do

1.     If you find someone collapsed, you should first perform a primary survey. Do not place your face close to theirs. If this shows that they are unresponsive and not breathing, shout for help. Ask a helper to call 999 or 112 for emergency help while you start CPR. Ask a helper to find and bring a defibrillator, if available.

o   Ask your helper to put the phone on speaker and hold it out towards you, so they can maintain a 2m distance

o   If you are on your own, use the hands-free speaker on a phone so you can start CPR while speaking to ambulance control

o   Do not leave the casualty to look for a defibrillator yourself, the ambulance will bring one.

2.    Before you start CPR, use a towel or piece of clothing and lay it over the mouth and nose of the casualty.

Start CPR. Kneel by the casualty and put the heel of your hand in the middle of their chest.

Put your other hand on top of the first. Interlock your fingers making sure they don't touch the ribs.

Keep your arms straight and lean over the casualty. Press down hard, to a depth of about 5-6cm before releasing the pressure, allowing the chest to come back up.

o   The beat of the song "Staying Alive" can help you keep the right rate

o   Do not give rescue breaths.

3.    Continue to perform CPR until:  

o   emergency help arrives and takes over

o   the person starts showing signs of life and starts to breathe normally

o   you are too exhausted to continue - if there is a helper, you can change over every one-to-two minutes with minimal interruptions to chest compressions

o   a defibrillator is ready to be used.

4.    When the helper returns with a defibrillator, ask them to switch it on and take the pads out while you continue with CPR. They should remove or cut through clothing to get to the casualty's bare chest. They also need to wipe away any sweat.

o   The defibrillator will give voice prompts on what to do.

5.     They should attach the pads to the casualty’s chest by removing the backing paper. Applying the pads in the positions shown.

o   The first pad should be on the upper right side below the collar bone.

o   The second pad should be on the casualty’s left side below the arm pit.

6.    The defibrillator will analyse the heart's rhythm. Stop CPR, and make sure no one is touching the casualty. It will then give a series of visual and verbal prompts that should be followed.

o   If the defibrillator tells you that a shock is needed, tell people to stand back. The defibrillator will tell you when to press the shock button. After the shock has been given, the defibrillator will tell you to continue CPR for two minutes before it re-analyses.

o   If the defibrillator tells you that no shock is needed, continue CPR for two minutes before the defibrillator re-analyses.