First Aid

Also known as an Automated External Defibrillator (AED), a Defibrillator is a device that restores a normal heartbeat – by sending an electric pulse or shock to the heart – in the case cardiac arrest or if the heart suddenly stops.

AEDs, which are in many public spaces, were developed to save the lives of people experiencing sudden cardiac arrest. While even untrained bystanders can use these devices in an emergency, defibrillator training is recommended for workplaces, communities and individuals.

How does an AED Work?

An AED is a lightweight, battery-operated, portable device that checks the heart’s rhythm and sends a shock to the heart to restore a normal rhythm.

Sticky pads with sensors (electrodes) are attached to the chest of someone who is having cardiac arrest. The electrodes send information about the person’s heart rhythm to a computer in the AED, which then analyses the heart rhythm to find out whether an electric shock is needed. If needed, the electrodes deliver the shock.

Signs of Cardiac Arrest

Cardiac arrest is a serious cardiac event that occurs when the heart stops pumping blood around the body. A person suffering a cardiac arrest will stop breathing and lose consciousness almost immediately.

For many people, a cardiac arrest comes without any warning signs. However, some people do experience some warning signs before a cardiac arrest. These can include:

  • Chest pain
  • Dizziness
  • Palpitations
  • Fainting
  • Breathlessness.

Someone who has already had a cardiac arrest will be:

  • Unconscious
  • Unresponsive
  • Not breathing.

Using a Defibrillator in an Emergency

A person whose heart stops from sudden cardiac arrest must get help within 10 minutes to survive. Fainting is usually the first sign of sudden cardiac arrest.

If you think someone may be in cardiac arrest, try the following steps:

  • If you see a person faint or if you find a person already unconscious, first confirm that the person cannot respond. The person may not move, or his or her movements may look like a seizure.
  • You can shout at or gently shake the person to make sure he or she is not sleeping, but never shake an infant or young child. Instead, you can gently pinch the child to try to wake him or her up.
  • Check the person’s breathing and pulse. If the person is not breathing and has no pulse or has an irregular heartbeat, prepare to use the AED as soon as possible.

If someone is having sudden cardiac arrest, using an AED and giving CPR can save that person’s life. When using an AED:

  • Call 1-1-1. 
  • If two rescuers are present, one can provide CPR while the other calls 1-1-1 and retrieves an AED.
  • Ensure the area around the person is clear. If a bystander touches the person, this could interfere with the AED’s reading of the person’s heart.
  • If an electric pulse or shock is needed to restore a normal rhythm, the AED uses voice prompts to tell you when and how to give the shock, and electrodes deliver it. Some AEDs can deliver more than one shock with increasing energy.
  • The device may instruct you to start CPR again after delivering the shock.

AED Training

Knowing how to operate an AED could save someone’s life. In fact, every minute defibrillation is delayed, the chances of survival for someone experiencing cardiac arrest decrease by 10%.

AED defibrillator training is recommended for workplaces, communities and individuals. While defibrillators are easy to use – with many now including voice prompts to help rescuers navigate the situation – nothing can replace hands-on training to increase confidence in using a defibrillator, and help you use one as quickly as possible.

TriEx offers practical defibrillator training – including where you can find an AED, when to send for one and when and how to use it. We also cover important topics such as patient preparation, current CPR processes, and patient dignity and privacy.

Finding an AED

It’s estimated that there are around 9,000 AED devices publically available throughout New Zealand. TriEx has an AED in our foyer, which is available to the public in case of an emergency in the area.

To find an AED in your location, we recommend heading to the AED Locations website, or downloading the app (available for Android and iPhone). AED Locations offers easy-to-use search functionality to help you find the nearest publically accessible defibrillator in an emergency.

If your workplace is interested in having an AED onsite, Alsco offers a Rented Defibrillator service – which is a great alternative to purchasing a defibrillator outright.


To learn more about renting a defibrillator for your workplace, visit the Alsco website.

To learn more about Defibrillator training or to book a training session for you team, please contact the TriEx team on 0800 487 439 or via email at