How Automated External Defibrillators (AEDs) and CPR Work Together to Save Lives

Lucy Dale

Published:4 November 2024

When a heart suddenly stops, what’s the one-two punch that can bring someone back? Most people know about CPR, and some may be aware of defibrillators, but how exactly do they work together? What happens when these two life-saving methods combine in those crucial moments to turn the tide against cardiac arrest? Let’s break down the powerful partnership between Automated External Defibrillators (AEDs) and CPR and explain why understanding their joint role can be the key to saving lives.

What Happens During Cardiac Arrest?

Cardiac arrest occurs when the heart suddenly stops beating effectively. Unlike a heart attack, which is caused by a blockage in blood flow, cardiac arrest is an electrical malfunction that causes the heart to stop pumping blood. In this situation, oxygen can’t reach the brain or other vital organs. Within minutes, death can occur if the heart isn’t restarted. This is where the combination of CPR (Cardiopulmonary Resuscitation) and AED (Automated External Defibrillator) can step in to turn the tide.

The Role of CPR: Keeping Oxygen Flowing

When someone suffers a cardiac arrest, CPR serves as the immediate action to keep blood and oxygen circulating through the body. By performing chest compressions, you manually pump blood to the brain and other organs, buying precious time until professional help or a defibrillator is available.

How to Perform CPR:

Check Responsiveness: Tap the person and shout to see if they are responsive. Call emergency services if they aren’t.
Begin Chest Compressions: Place your hands on the centre of the chest and push hard and fast, aiming for 100-120 compressions per minute. Let the chest rise completely between compressions.
Breaths or Hands-Only: If trained, give rescue breaths after every 30 compressions. Otherwise, hands-only CPR is still highly effective until an AED arrives.

Chest compressions ensure the brain gets oxygenated blood, but it doesn’t restart the heart. This is where the AED comes into play.

The Role of the AED: Jumpstarting the Heart

The AED is a portable device designed to assess the heart’s rhythm and deliver a shock if necessary. Cardiac arrest often results from an irregular heart rhythm known as ventricular fibrillation, where the heart’s electrical signals are out of sync, causing it to quiver instead of pump. An AED’s purpose is to “shock” the heart back into a normal rhythm.

How to Use an AED:

Turn on the AED: Follow the machine’s voice prompts. AEDs are designed to be user-friendly, with clear instructions.
Attach the Pads: Place the pads on the person’s bare chest as indicated by the diagram (one on the upper right chest and the other on the lower left side).
Let the AED Analyse: The device will check the heart’s rhythm and advise if a shock is needed.
Clear the Area and Administer Shock: If instructed, ensure no one is touching the person, then press the shock button.
Resume CPR: After the shock, immediately resume chest compressions. The AED will reassess after a couple of minutes.

4 November 2024

Why CPR and AEDs Are Better Together

While CPR sustains life by keeping blood moving through the body, an AED is needed to correct the heart’s rhythm. Together, they provide the best chance for survival. Here’s why their combination is so powerful:

CPR alone can’t restart a heart: CPR is vital for maintaining blood flow, but it can’t reset the heart’s rhythm. This is where the AED steps in.
The AED can’t keep blood moving: After the AED delivers a shock, CPR helps maintain circulation while the heart stabilises.
Timeliness is critical: For every minute without CPR and defibrillation, survival chances decrease by 10%. Combining the two within the first few minutes of cardiac arrest can increase survival rates by up to 70%.

The Science Behind Their Synergy

When you perform CPR, you keep oxygen flowing, ensuring that vital organs, including the brain, don’t sustain damage. When the AED arrives, it determines whether a shock is necessary and, if so, delivers it to restore the heart’s normal function. It’s this alternating pattern of CPR and AED use – compressions to maintain circulation, shock to reset the heart – that gives a person in cardiac arrest the best chance of survival.

The combination also works in what’s known as the “Chain of Survival,” which includes:

Early recognition and calling for help.
Early CPR to keep oxygenated blood flowing.
Early defibrillation to reset the heart’s rhythm.
Early advanced medical care once emergency responders arrive.

Each link in the chain is vital, and AEDs and CPR are at the core of this life-saving process.

The Importance of Defibrillator and CPR Training

One of the biggest barriers to using AEDs and performing CPR is the fear of doing it wrong. This hesitation can cost lives. That’s why comprehensive training in both CPR and AED use is critical. When individuals know what to do, they act quickly and confidently. Training programs demystify the process and give people the hands-on experience they need to take control in an emergency.

At Defib World, we provide training and resources to equip workplaces, schools, and communities with the knowledge and skills they need to save lives. Knowing how to effectively use a defibrillator and perform CPR isn’t just a skill; it’s a responsibility to those around you.

Final Thoughts: Be Prepared to Save a Life

When cardiac arrest strikes, time is the enemy. CPR and AEDs are the ultimate team in fighting against the clock. When used together, they maximise the chances of survival in those critical first minutes. Whether at work, in public, or at home, being prepared to act quickly with both CPR and an AED can mean the difference between life and death.

Don’t wait until it’s too late – get trained, get informed, and be ready to save a life.