What Is a Defibrillator?
A defibrillator is a life-saving device designed to treat sudden cardiac arrest (SCA) by delivering an electric shock to the heart. The shock helps restore a normal rhythm, giving the victim the best possible chance of survival. Whether in workplaces, public spaces, schools, or homes, having access to a defibrillator can mean the difference between life and death.

ViVest X3 being carried onto train
What Does a Defibrillator Do?
When someone suffers a sudden cardiac arrest, the heart stops beating properly. It may quiver irregularly (ventricular fibrillation) or stop altogether. A defibrillator (also known as an AED – Automated External Defibrillator) analyses the heart’s rhythm and, if necessary, delivers a controlled shock to restart the heart’s normal function.
Modern AEDs are designed to be used by anyone, even without medical training. In fact, voice prompts, clear diagrams, and automated checks guide the user through every step of the rescue process. Year on year new changes help make these devices user friendly and portable. The aim is to get to the victim as quickly as possible, every second in crucial during an SCA.
Heart Attack vs Cardiac Arrest – What’s the Difference?
Although many people use the terms interchangeably, a heart attack and a cardiac arrest are very different medical emergencies:
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Because of this difference, it’s critical to recognise that AEDs are the means to treat cardiac arrest, not a heart attack. However, a heart attack can lead to cardiac arrest, so fast action is always vital.
How Do You Use a Defibrillator?
Using a defibrillator is simpler than many people think. Here’s a basic overview:
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Turn on the AED and follow the voice prompts.
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Expose the chest and attach the electrode pads as shown.
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Allow the device to analyse the heart rhythm.
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If a shock is advised, ensure no one is touching the patient and press the shock button (if manual). Some AEDs deliver the shock automatically.
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Continue CPR immediately after the shock until emergency services take over.
Importantly, an AED will only deliver a shock if it detects that one is needed. This makes them safe to use by both trained and untrained bystanders.
Why Every Workplace and Public Space Needs a Defibrillator
According to the Resuscitation Council UK, early defibrillation can increase survival rates by up to 70% if delivered within the first 3-5 minutes of collapse. However, without access to an AED, the chances of survival decrease by about 10% for every minute that passes.
Installing a defibrillator isn’t just about ticking a compliance box. Ultimately, it’s about saving lives – your employees, visitors, or even your own.
We supply a full range of defibrillators and AED accessories, and offer First Aid Training Course UK wide to ensure your staff are confident and capable in an emergency.
Know the Difference, Save a Life
Understanding the difference between a heart attack and a cardiac arrest is crucial. More importantly, knowing how and when to use a defibrillator could save someone’s life.
If you don’t yet have a defibrillator on site, or if you need advice about choosing the right AED, contact us today. Explore our Defibrillators On Sale to find out how we can help you be prepared.