Why Defibrillate?

Sudden Cardiac Arrest (SCA) is where normal circulation of the blood immediately stops due to failure of the heart to contract effectively and the person usually dies!  It can strike anyone, anywhere and without warning. In the UK alone it kills at least:

  • 2000 people every week
  • 250 people a day or
  • 1 person every 5 minutes.
  • 12 of those dying each week will be young people.
  • Currently the chance of surviving a SCA is less than 5% without the use of an Automated External Defibrillator (AED) and quality Cardio Pulmonary Resuscitation!

The better news is that if an AED is used in the first 5 minutes of a SCA the chance of survival can go up from 5% to 74%.

Follow the Chain of survival: Dial 999, start CPR, use the AED, Emergency services takeover

Early Defibrillation the only way to reboot a heart in SCA


Heart attacks and Sudden Cardiac Arrest

A Heart Attack, if severe can lead to a Sudden Cardiac Arrest but not always! They are not the same thing!

Symptoms of a heart attack can be experienced as tightness or pain in the chest, spreading to their arms, neck, jaw, back or stomach. For some the pain or tightness is severe, others may feel nothing more than a mild discomfort. They may feel light-headed or dizzy, short of breath, sweaty and nauseous. Most heart attacks are caused by coronary heart disease. This is when your coronary arteries narrow or `fur up` due to a gradual build-up of atheroma/ plaque (fatty material) inside their walls.

If the damage to the heart muscle as a result of the heart attack is severe enough the cells do not conduct electricity in the usual co-ordinated way and fire off charges erratically and chaotically, this is known as Ventricular Fibrillation (VF) and causes the heart to quiver or fibrillate. Circulation immediately stops; the victim collapses and suffers a Sudden Cardiac Arrest. Without rapid access to an AED the chance of surviving SCA is approximately 1 in 20

Not all sudden cardiac arrests are caused by a heart attack and have other possible causes such as: Electrocution, drowning accidents, recreational drugs, SADS (Sudden Adult Death Syndrome) Heart disease that is present at birth such as Wolff Parkinson White Syndrome and Long QT syndrome, muscle disease of the heart, including cardiomyopathies, heart surgery, sudden cardiac death /commotio cordis, (an impact injury over the surface of the heart usually in sport). Many victims of SCA have no history of heart disease and the only previous `symptom` may be one of unexplained fainting. In essence:

Heart Attack – `Plumbing` problem and may lead to a SCA

Sudden Cardiac Arrest – Electrical problem and is usually fatal

So why do we need an AED?

Defibrillation is the only way to stimulate the heart back into a normal rhythm following SCA; CPR alone will not usually achieve it! If the AED, having performed an ECG, identifies a `shockable` rhythm it will deliver a controlled electric shock so that the heart is momentarily stunned.  It tries to stop the heart fibrillating/quivering hence the device is called a DEFIBRILLATOR! At this point the hearts own built-in electrical pacemaker will hopefully kick-in and restore a normal cardiac rhythm, just like re-booting your computer!

Defibrillators can do no harm, only good. You cannot shock someone for fun or by accident, the AED will only be able to deliver a shock if it identifies a shockable rhythm and there are no reports of anyone ever being sued for using an AED with good intent.

These devices are simple and safe to use although extremely sophisticated in design. There are usually only one or two buttons to press, clear voice and visual guidance is given throughout and there is a very realistic chance of saving someone’s life if an AED is deployed quickly ………. and there will usually only be one chance!!


`An AED can be used safely and effectively without previous training; its use should not be restricted to trained rescuers, training should however be encouraged to help improve the time to shock delivery and correct pad placement`.

Do something really fantastic today. Find out where your nearest AED is located, familiarise yourself with it and be prepared to save someone’s life, and if you haven’t got access to an AED push to get a one in your workplace, sports hall, community centre, school, wherever people meet, because as the old saying goes `to save one life is as if to save the world`, you never know, the life that needs saving could be yours!