skip to primary navigationskip to content


The Department has a defibrillator, located beside Reception.
If you simply want to see how to use the defibrillator, 
click here for the instructional video.

This page contains the following information:

Sudden cardiac arrest

Sudden cardiac arrest can happen to anyone, anywhere and at any time. Many victims of sudden cardiac arrest have no warning symptoms.

Ventricular fibrillation is a chaotic quivering of the heart muscle that prevents it from pumping blood. The only effective treatment for ventricular fibrillation is defibrillation. The defibrillator (also known as an AED) treats this condition by sending an electric shock across the heart, which can cause it to start beating regularly again. If this is not done within the first few minutes the victim is not likely to survive.

When to fetch the defibrillator (AED)

If you have a casualty who:

  • does not respond when shaken, and
  • is not breathing normally


they may be in need of defibrillation.

In the daytime, call 37499 for a first aider. Tell reception that you have an unconscious casualty who is not breathing. They will relay this to the first aiders, who will bring the defibrillator and take care of the emergency 1-999 call for you. They may ask for your help in getting the ambulance crew and/or rapid response paramedic to the casualty.

Out of hours: SHOUT FOR HELP. Either send someone for the defibrillator, or go yourself. Time is of the essence.

In the meantime, get someone to call 1-999 for an ambulance. Give them the message that the casualty is unconscious and not breathing. Give the address (Cavendish Laboratory, J J Thomson Avenue, Cambridge CB3 0HE).

Where the defibrillator is

The defibrillator is in a red carrying case on the wall close to the first aid room (just beside reception). Familiarise yourself where it is NOW. Then you will be able to find it quickly if you ever need to.

Lift it out of the trough and take the whole thing, carrying case and all, to the casualty.

How to use the defibrillator

Then, ensure there are no flammable gases in the vicinity, or a large scale spillage of a solvent. If necessary drag the casualty out of the area.

Open the carrying case. Inside you will find the defibrillator and a pair of scissors. The pads need to be applied to the bare skin so, if necessary, use the scissors to enable you to do this.

Pull up the handle on the SMART Pads cartridge. Place the pads on the patient's bare skin exactly where the pictures indicate. Hands off the casualty while the unit analyses the heart rhythm of the casualty. If instructed, press the shock button.

Check that someone has called 1-999.

Be prepared to assist first aiders in meeting the ambulance/first responders and guiding them to the casualty OR, IF THIS IS OUT OF HOURS get people around you to do this. You need one person outside, with an access card, to meet the ambulance/first responders, let them in and guide them to the casualty. Ideally, get two people, as the ambulance and first responder will rarely arrive at the same time.


When the shock has been delivered, the unit may invite you to embark on cardio-pulmonary resuscitation (CPR). Press the blue button on the unit to talk you through this. To get a flavour of what this entails, watch the Vinnie Jones advert (full length version). You DON'T have to do mouth to mouth resuscitation to be able to make a difference (although first aiders will still do this). If the patient starts to move after the shock has been delivered, or starts to regain consciousness, CPR will not be required.

Is it safe?

These units are very safe. They only deliver a shock to a heart that needs one. If you forget to back away from the casualty while the unit is analysing the heart rhythm, you will be reminded by the unit to do so. Think about it - your casualty is unconscious and not breathing - you cannot make it any worse. However, by using a defibrillator you could increase their chance of survival by as much as 60%.

To prepare yourself, read the FAQs on their use here.

Next, watch the instructional video for the make and model that the Department has purchased.

Finally, why not watch the BBC news item that demonstrated how easy it was to use the device.

Want to know more? Enrol on a 'Heart Start' course - email the safety officer.


This page was last updated on 01 October 2013