About Defibrillators

Automatic External Defibrillator ( AED)

Have you ever noticed that more and more defibrillators are around now, train stations, shopping centres, Airports, Community centres, well thats because it is recognised that to save a persons life from cardiac arrest then they have a 50 to 70% chance of survival if there is a defibrillator available within five minutes –  after 15minutes their chances may be less than 5%

The use of AEDs by people who were not health professionals was introduced in the UK as a government-led initiative (the ‘Defibrillators in Public Places Initiative’ 1999) which placed AEDs in airports, railway stations, and other public places where ambulance service records showed that SCA ( Sudden Cardiac Arrest) occurred most frequently. Staff working in these places were trained in CPR and to use AEDs that were positioned nearby.

Would you know how to use one ?

The AED is designed to be used safely by almost anyone, so its use is not resricted to trained resuers, however training does improve performance which can lead to a better outcome.They are designed to be stored for long periods without use and require very little routine maintenance. Several models are available from the manufacturers or through medical equipment companies.

AEDs come in different types of makes but they will all have similar layouts.

Personally I would recommend training to everyone to give them the confidence and understand the safety measures involved. This post will give you some gudance but it does not give you that hands on training, when I have been teaching how to use the AED in training, most of the class particpants comment how confident they feel now they have been shown.

All AEDs analyse the victims pulse electronically through what’s called an ECG rhythm, if the AED identify that there is an ECG rhythm there it will not shock.

Activating an AED

Some AEDs will automatically switch on when you open the lid.With others you may have to press the on button. Some AEDs the pad leads have to be connected once the voice prompt tells you.

Attaching the PADs

Remove Pads From Packaging

Look at the diagram ( Instuctions on the pads)

The pads will have a sticky side which usually has a plastic cover that will have to be removed. place the pads on the patients chest as shown.

One pad should be placed below the centre of the right collarbone,

The other pad should be placed below the left armpit, on the side of the chest wall, over the lower rib cage.

It is important which way round the pads are placed. 

Sometimes you may come across complications when trying to place the pads, such as the pad placement is wet from sweating or the area has excessive hair. in these cases then you should should try and wipe the sweat away with a towel and if possible shave the area where the pads need to be placed. If a shaver is not available then place the left side pads further back to the side of the rib cage. The current that travels from pad to pad will miss the heart if not placed correctly.

AED Safety

  • Be aware of patches on the skin – Patches such as GTN patches deliver medication through the skin, avoid placing pads on these patches.
  • No jewellery around or near the electrodes
  • The casualty should not be touching any metal
  • Nobody should be in contact with the casualty during the shock process
  • The casualty should be dry
  • No GTN patches which may catch fire
  • There should be no free flowing gases ( If the casualty is using oxygen remove to at least one metre away before the shock is given.

The casualty’s chest must be sufficiently exposed to enabled the pads to be placed correctly, clothing may have to be cut off


When the AED is analysing everybody should stay clear of the casualty, the AED will warn to stay clear.

  • Ensure that nobody is touching the casualty whilst the AED is analysing the heart rhythm, this can lead to inaccurate result.
  • Do not stop giving chest compressions for more than 10 seconds during anlysis.
  • Listen and fiollow the voice prompts.

No Shock Indicated

If you get a “no shock advised” instruction from the AED it can mean the victim is not in a ‘shockable’ rhythm

  • The voice prompt may direct you to start CPR, start chest compressions and resue breathing immediatly.
  • Maintain CPR for two minutes or until prompted to stop.
  • With simple audio and visual commands, AEDs are designed to be simple to use for the layperson.

Shock Indicated

f the AED indicates that a shock is required,

  • make sure that everyone is “CLEAR” of the casualty.
  • Tell everyone assisting you to stay clear of the casualty and ensure that you are clear of the victim as well.
  • Then press the shock button on the AED machine to deliver the first shock. (Fully automatic AED will shock the victim automatically)
  • Immediately following the shock, begin 2 minutes of CPR as instructed by the AED.
  • Perform CPR in cycles of 30 chest compressions to 2 breaths for 2 mins or until the AED informs you to “Stop CPR”

Note: Do not remove the AED chest pads while performing CPR.


Users of an AED are not expected to carry out any maintenance tasks other than replacing expired batteries, electrode pads, and other consumable items (razor, airway adjuncts, plastic gloves). Even then, the shelf-life of these (unused) is usually 3 – 5 years, so any maintenance tas

ks are infrequent. In all cases the manufacturer’s instructions should be followed.

All currently available AEDs perform regular self-checks and if a problem is detected it will be indicated. In most cases they show this by a warning sign or light visible on the front of the machine. Those owning an AED should have a process in place for it to be checked regularly and frequently (ideally daily) for such a warning, and for appropriate action to be taken when necessary. If this task is delegated to individuals, allowance must be made to ensure that the checks are not neglected during absence on holidays, sick leave etc. Most manufacturers provide a replacement AED while one is removed for servicing, and the arrangements for this should be clarified and agreed during the process of buying the AED.



Leave a Comment

Your email address will not be published. Required fields are marked *