Cardiac arrest, CPR and defibrillator

Cardiac arrest means the heart stops pumping blood around the body. The brain can only tolerate a very short time without oxygen and therefore your actions in the first minutes are absolutely crucial to whether the affected person survives. With simple practised actions an ordinary person can save a life until the ambulance arrives.

§Survival chain

First aid for cardiac arrest is based on the 'chain of survival' — a series of links that each increase the chance of survival. The chain consists of early recognition and alert, early CPR, early use of defibrillator, and rapid advanced treatment from the ambulance. Each link must be in place — the chain is no stronger than its weakest link.

§How you ensure good team dynamics

Check consciousness by speaking to the person and gently shaking the shoulders. If the person does not respond, open airway by tilting head back gently and lifting chin. Look, listen, and feel for normal breathing for up to 10 seconds. If the person is unconscious and not breathing normally, treat as cardiac arrest

§Cardiopulmonary resuscitation

Cardiopulmonary resuscitation (CPR) consists of chest compressions and rescue breaths. Place your hands in the middle of the chest and press hard and fast to pump blood around. Let the chest rise completely between each compression. CPR is performed in series with compressions followed by breaths, and you continue until the person wakes up, a defibrillator is ready, or professional help takes over. Follow the training and proportions you have learned in your first aid course.

§Defibrillator (AED)

An automatic external defibrillator (AED) analyzes the heart rhythm and gives a signal if a shock should be delivered. It talks you through the entire process. Turn it on as quickly as possible, place the electrodes on the bare chest as shown in the pictures, and follow the machine's spoken instructions. Do not touch the person while the defibrillator analyzes or delivers a shock. Between shocks, continue CPR according to the machine's instructions.

• 01Turn on the defibrillator immediately and follow its voice
• 02Bare chest — remove or cut away clothing
• 03Place the electrodes as shown in the illustration
• 04Stand free of the person under analysis and shock
• 05Continue CPR between shocks until help takes over

“Doing something is always better than doing nothing. The worst mistake at heart attack is not to act.”

— Basic first aid rule