How an AED Can Save Lives

The acronym AED stands for Automated External Defibrillator. They are sometimes referred to as public access defibrillators (PADs) or simply defibrillators. They were first invented and developed in 1965 by Professor Frank Pantridge, a Northern Irish cardiologist.

The basic AED machine definition is that it is a portable medical device. The main AED function is to deliver a controlled electric shock to the heart of someone who is experiencing cardiac arrest to get their heart beating again.

Chances are you have come across an AED machine at some point in your life. AEDs are placed in many public places such as shopping centres, cinemas, gyms and shops. They are usually stored in wall-mounted cabinets or cases in public places and are usually marked with clear AED or defibrillator signage, commonly including a green heart symbol.

Cardiac arrest occurs when an abnormal heart rhythm – also called ventricular fibrillation (VF) – causes a person’s heart to stop pumping. This stops the flow of blood and causes the person to collapse, become unresponsive, have breathing problems or stop breathing altogether.

It’s important to note that a heart attack is not a cardiac arrest. A heart attack is usually caused by a blockage in a person’s circulatory system, while a cardiac arrest is the result of an issue with the heart’s electrical system. Heart attack patients are often conscious, whilst cardiac arrest patients are unconscious.

There are more than 40,000 out-of-hospital cardiac arrests each year in the UK, according to the British Heart Foundation (BHF). They can happen to anyone, at any time, regardless of their age or fitness level.

However, cardiac arrest have been shown to occur more frequently in those who have:

• Coronary heart disease
• Heart attack
• Inherited heart conditions
• Cardiomyopathy a
• Congenital heart disease
• Heart valve disease
• Acute myocarditis

Cardiac arrest can also be brought about by:

• Electrocution
• Drug overdoses
• Severe haemorrhaging
• Hypoxia

When a person is in cardiac arrest, action must be taken within the first three to five minutes to prevent irreversible brain damage or death.

An AED measures the rhythm of a person’s heart and then calibrates the required burst of electricity to be delivered to stop the heart momentarily. This can reset the heartbeat back to a normal rhythm and keep the person stable until professional medical assistance arrives. Although they are used by many emergency responders, AEDs are purposefully designed to be used by non-medical personnel in the case of an emergency.

If someone is unresponsive, call 999 immediately, use speakerphone if you can, and assess their breathing while you wait for the call to be answered. If the person is unresponsive and not breathing normally, start CPR immediately and use an AED as soon as one is available.

If someone else is present, ask them to fetch the nearest AED while you stay with the person and continue CPR.

Do not delay calling 999 or starting CPR to search for an AED; the 999 call handler can help identify the nearest registered defibrillator and direct a bystander to it where possible.

Once the AED is available, one person should continue CPR, whilst the other sets up and turns on the device. As soon as it is turned on, it will start to provide pre-recorded voice prompts and instructions for each step of the process.

An AED will usually ask you to perform the following steps:

Step One: Remove clothing from the chest of the person who requires aid. Wipe the chest area dry if it is wet.

Step Two: Peel plastic protective coverings from the AED pads and place them on the chest. The AED will have pictures to show correct placement. If required, plug the pad connector into the AED machine.

Step Three: Stand clear while the AED charges and analyses the person’s heartbeat.

Step Four: The AED will then advise if a shock is needed.

Step Five: If a shock is required, make sure no one is touching the person, whilst the shock is delivered. You may be required to press the ‘shock’ button on some types of AED.

Step Six: Stay clear until advised to start CPR by the AED machine.

Step Seven: Perform CPR for two minutes at which point the AED machine will reanalyse the person’s heartbeat.

Step Eight: Continue this process until medical help arrives, or until the patient begins to show signs of recovery. If they do recover, leave the AED attached, and put them in the recovery position.

AEDs relatively safe. However, given that they deliver an electric shock there are certain precautions to be aware of:

• Water: It is usually safe to use an AED if the person is on a wet surface, but dry their chest first so the pads stick properly and make sure nobody is touching them when a shock is delivered.
• Fire: If there are combustible materials in the near vicinity, do not operate the AED.
• Metal: It is usually safe to use an AED if the person is on a metal or other conductive surface, provided the pads are applied correctly and nobody is touching the person when the shock is delivered.
• Other People: Ensure nobody is touching the patient when the shock is delivered, including yourself. The AED will likely prompt you to either press a button to deliver the shock or warn you to move away when a shock is delivered.
• Pacemakers: If the patient is wearing a pacemaker or implanted defibrillator, the AED pads should be placed one inch or more away from them.

The Resuscitation Council UK provides additional guidance on AED use and safety.

AEDs are life-saving tools placed into public areas for any of us to use in the event of cardiac arrest. If one is used within the first three minutes of a person collapsing, the survival rate can be as high as 90%. So, it’s essential to make use of them whenever there is a chance they may help.

If you are interested in learning more about how to use an AED or how to improve your First Aid skills, then Human Focus offers online AED training as well as First Aid training.

Our AED Defibrillator Training course is assured by RoSPA, and our First Aid Courses toolkit includes courses approved by recognised independent bodies, including RoSPA, CPD and IIRSM. Participating in these online e-learning courses can give you the skills to provide life-saving assistance in an emergency situation.