Cardiac Arrest and CPR: A Life-Saving Guide

Sudden cardiac arrest kills tens of thousands of people every year in the UK. Knowing how to respond quickly and effectively can significantly increase a person’s chance of survival.

What Happens During Cardiac Arrest?

When someone suffers a cardiac arrest, their heart stops pumping blood effectively. In around 85% of cases, the heart goes into ventricular fibrillation (VF).

In this state, the heart:

• Quivers or “fibrillates” instead of beating properly
• Fails to pump blood around the body
• Prevents oxygen from reaching vital organs

Without immediate action, the person will not recover.

Why CPR is Essential

The primary first aid treatment for cardiac arrest is CPR (cardiopulmonary resuscitation).

CPR is a combination of:

• Chest compressions
• Rescue breaths

This process helps to circulate oxygenated blood to the brain and vital organs until emergency services arrive.

Important: CPR does not restart the heart. It keeps the body alive until a defibrillator can be used.

The Role of an AED (Defibrillator)

To restart the heart, an AED (Automated External Defibrillator) is required.

An AED:

• Delivers an electric shock to restore a normal heart rhythm
• Is often brought by paramedics or available in public places
• Greatly increases survival chances when used quickly

Every minute without CPR or defibrillation reduces survival by around 10%.

Why Immediate Action Matters

Ambulance response times are often around 8 minutes or more. Without intervention:

• Survival chances drop rapidly
• Brain damage can occur within minutes

Currently, only around one-third of cardiac arrest victims receive CPR. Simply attempting CPR can double or even triple survival chances.

Step-by-Step: How to Perform CPR

1. Check for Danger and Responsiveness

Ensure the scene is safe. Approach the person, introduce yourself, and ask if they are okay.

Gently tap their shoulders and shout for a response.

2. Call Emergency Services

If there is no response, call 999 or 112 immediately and ask for an ambulance.

Put your phone on speaker mode and follow the dispatcher’s instructions.

3. Check Breathing

Open the airway using the head tilt, chin lift technique and check for normal breathing for up to 10 seconds.

If they are not breathing normally, begin CPR.

4. Send for an AED

If others are nearby, ask someone to locate and bring an AED.

5. Start Chest Compressions

• Place the heel of one hand in the centre of the chest
• Place your other hand on top and interlock your fingers
• Push hard and fast

Compression guidelines:

• Depth: 5–6 cm
• Rate: 100–120 compressions per minute (about 2 per second)
• Allow full chest recoil between compressions

6. Give Rescue Breaths

After 30 compressions:

• Open the airway again
• Pinch the nose
• Give 2 breaths, each lasting about 1 second
• Watch for the chest to rise

Continue the cycle of 30 compressions to 2 breaths.

7. Continue Until Help Arrives

Keep performing CPR until:

• Emergency services take over
• An AED is ready to use
• You are physically unable to continue

If possible, swap with another rescuer every 2 minutes to avoid fatigue.

Key Takeaway

CPR is simple, but it saves lives. By maintaining blood flow and oxygen to the brain, you keep the person in a condition where paramedics and defibrillation can restore a heartbeat.

Act quickly, stay calm, and remember: doing something is always better than doing nothing.