A defibrillator is a device that gives a high energy electric shock to the heart of someone who is having a Cardiac arrest.

The high energy shock is called defibrillation , and its an essential part in trying to save the life of someone who is in Cardiac arrest.

A defibrillator may also be referred to as a defib , and AED ( Automated external defibrillator ) or a PAD ( Public Access Defibrillator)

The heart is controlled by an electrical impulse that makes it beat in a regular rhythm keeping you alive. When a person has a sudden Cardiac arrest ( SCA ) the normal rhythm becomes disrupted and disorganized , which means their heart cannot beat properly and they will not be able to breath normally.

For every minute that someone is in Cardiac arrest without receiving CPR and having a defibrillator used on them, their chances for survival decrease by 10%.

That is why it is so important to act immediately.

A defib gives a jolt of energy to the heart, which can help restore the rhythm, and get it beating normally again. A defib will not harm the person suffering from Cardiac arrest , and will only give them a shock if and when it is needed.

The steps you need to take to do CPR

Before you approach the person who has collapsed, check your surroundings for danger.

  1. Shout for help. 
  • Shake them gently.
  1. Look and listen for signs of normal breathing. 
  • Look for the rise and fall of their chest.
  1. Call 999.  
  • Put the phone on loudspeaker and tell them you are with someone who is not breathing.
  1. Fetch a defibrillator if you can. 
  • The ambulance call handler will tell you where the nearest automated external defibrillator (AED) is. If someone is with you, ask them to fetch it and bring it back. Do not leave the person if you are on your own.
  1. Start chest compression's: 
  • interlock your fingers
  • place your hands in the center of the chest
  • push down hard and then release twice per second, and don’t stop. The ambulance call handler will help you.
  1. If you have a defibrillator, switch it on and follow the instructions.  
  • A defibrillator will tell you exactly what to do.
  1. Continue CPR until: 
  • the AED asks you to pause while it reanalyses and gives another shock if needed
  • a paramedic arrives and tells you what to do
  • the person shows signs of life.

By developing the skills and confidence to follow these simple steps, you could be a lifesaver in an emergency.

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Thanks to Alex Johnson for illustrations