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How to Use a Defibrillator


A defibrillator can be used to deliver a life saving electric shock to the heart to get it beating again during cardiac arrest. In a survey conducted by the St. John’s Ambulance service, 60% of people asked were unaware what a defibrillator should be used for, with many believing that only doctors, nurses and paramedics were qualified to administer shocks to heart attack victims.

This has certainly been the case for many years, although the development of the Automated External Defibrillator (AED) has changed that. An AED is compact and lightweight and is designed to be portable and easily administered. It provides clear spoken instructions to prompt the user on the correct sequence of steps to take which makes it possible for someone who has only had a little training to provide lifesaving medical treatment after a cardiac arrest.

When should a defibrillator be used?

A defibrillator should be used following a suspected heart attack when a patient has stopped breathing and is in cardiac arrest. When an AED is attached to a patient it analyses the rhythm of the heart to determine whether a shock is necessary, which reduces the chance of human error.

Because of the importance of speed in administering an electric shock during cardiac arrest, and the ease of use, AED’s can now be found alongside first aid kits in many places of work and areas where crowds often gather.

How to use a defibrillator

There are a number of steps which must be followed when using an Automated External Defibrillator to ensure the correct intensity of shock is delivered.

Step 1 - Confirm the patient is in cardiac arrest

Check for a pulse. Tilt the head back and lift the chin to free the airway and check for breathing. If there is no breathing or pulse – or either is erratic - an AED should be used.

H3: Step 2 – Expose the chest

Remove or cut clothing to expose the chest and remove metal objects such as necklaces or underwire bras which could conduct electricity. Dry the chest if it is wet and check for any standing water. Move the patient to a dry area if necessary to ensure the AED can be used safely.

Step 3 – Switch on AED and apply pads to the bare chest

The AED will be less effective on a hairy chest. An AED responder kit contains a razor to shave the chest to ensure good contact with the adhesive pads. After attaching the pads make sure that the wires are connected to the AED.

Step 4 – Wait while the AED assesses the heart rhythm

The AED will provide step by step instructions on the procedures to follow and will assess the patient’s heart rhythm to determine if an electric shock is required, and if so, the intensity of shock to be delivered.

Step 5 – If a shock is required

The AED will indicate a shock is necessary and will automatically charge. When ready, the AED will instruct you to stand clear and administer the shock by pressing a button on the AED.

Step 6 – Check to see if the patient has started breathing

After the AED has discharged, check to see if the patient has started breathing again.

Step 7 – Administer CPR

If the patient is still not breathing CPR should be administered. 30 chest compressions should be administered followed by two rescue breaths. The process should be repeated until instructed otherwise by the AED.

Who should purchase a defibrillator?

According to the British Heart Foundation around 60,000 people have a cardiac arrest out of hospital every year. The probability of surviving cardiac arrest decreases by ten percent every minute until CPR and/or defibrillation is administered. Defibrillators are therefore most valuable in rural locations and areas where road traffic congestion can delay the arrival of the emergency services. Many employers are also purchasing portable defibrillators for the workplace to ensure that urgent medical treatment can be administered without delay.

Training on the use of defibrillators

Although modern AED devices provide spoken instructions on the steps to follow when using the device it is important to attend a short training course administered by a qualified instructor. Knowledge of how to use an AED can save valuable time in case of an emergency. The St. Johns Ambulance Service offers a training course on the use of defibrillators at centres up and down the country, these are provided free with any defibrillator purchased from ESE Direct.

Our range of defibrillators and AED responder kits

Our defibrillators are designed to be straightforward to use in emergencies and automate much of the process, providing spoken instructions on the steps that need to be taken to operate the device correctly. Each purchase includes one free place on a St. Johns Ambulance training course to cover the correct use of the device.

In addition to a defibrillator it is important to have an AED responder kit available for emergencies. The kit contains St. Johns Ambulance approved products for use with a defibrillator, including scissors for cutting clothing, a razor for shaving hair off the chest to ensure proper pad contact, safety gloves and a heat retaining blanket.

Photograph of Lee

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