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Choosing a defibrillator

11 Jun 2024

Someone using the Mindray defibrillator in an emergency

When you’re ready to get a defibrillator, you’ll need to choose which one to get.  Each type offers unique benefits and considerations that can impact their effectiveness in saving lives during a cardiac emergency. 

The type of defibrillator you choose will depend on:

  • the location it will be placed
  • who will use it
  • whether it will be used on children


Automatic vs Semi-automatic defibrillators

Defibrillators are either semi-automatic or fully automatic.  The difference is how much action is needed from the person using it.

  • A semi-automatic defibrillator analyses the person’s heart rhythm.  require the rescuer to press a button to deliver a shock when instructed by the device. This allows the rescuer to maintain control over the situation and ensures that nobody else is in contact with the patient’s body during the shock delivery, maximising its impact.
  • A fully automatic defibrillator will advise if a shock is needed. It will tell people to step back and then it will give a shock.


Benefits of Semi-automatic v Automatic defibrillators

Semi-automatic defibrillators: 

  • Rescuer control ensures no interference during shock delivery. 
  • Reduces the risk of a diminished shock due to contact with the patient’s body.


Fully automatic Defibrillators  

  • No need for rescuer intervention during shock delivery. 
  • Clear countdown announcement ensures safety for all involved. 


Common Features of Both Types: 

  • Both types of defibrillators require electrode pads to be applied to the patient before the shock delivery. 
  • Neither will deliver a shock without detecting an irregular heart rhythm, minimising the risk of accidental shocks. 
  • Both provide voice instructions to guide rescuers through the process, including when a shock has been delivered and when to continue CPR. 


Will it work for children?

For children under 8, the shock from a defibrillator needs to be weaker than it is for adults.  Some defibrillators let you switch easily from adult to child mode.  Others need different electrode pads that are suitable for use on children or a special ‘child key’ to switch mode.

We always recommend a defibrillator with a built-in-switch as this can save vital time during an emergency.

If you’re not sure whether to get a semi-automatic or fully automatic defibrillator, we can talk through your needs.

Call 020 7043 2493 or email:

If you are looking for part funding towards a semi-automatic or fully-automatic defibrillator you can apply via 



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