When someone suffers cardiac arrest the only definitive treatment is CPR and a shock from a defibrillator, but a defibrillator will only shock what it deems as a “shockable rhythm”.

An Automated External Defibrillator (AED) will first analyse the rhythm of the casualty’s heart and only deliver a shock if the heart is in a certain rhythm, but what is a shockable rhythm?

Sudden Cardiac Arrest (SCA) is a serious medical emergency in which the heart suddenly ceases the ability to effectively pump blood around the body. Awareness of SCA has increased recently, thanks in part to high profile cases involving sportspeople such as Christian Eriksen and Damar Hamlin.

These cases are, for many, the first time they have heard about sudden cardiac arrest. Elite athletes suffering SCA in a stadium full of people is a traumatic event for all involved and makes front page news.

Why is such a dangerous medical emergency happening to athletes who are among the fittest in society?

In recent years, defibrillators have become increasingly available to the public in the UK. These life-saving devices can now regularly be seen in public places such as restaurants, gyms, supermarkets and train stations.

Figures from defibshop’s Cardiac Coverage report show that the number of defibrillators per 10,000 people in the UK has risen from 4.17 in 2021 to 13.71 in 2024. Despite this, many less affluent areas are still below the national average for number of defibrillators, and survival rates for Out of Hospital Cardiac Arrest (OHCA) in these areas are lower as a consequence.

Children are incredibly resilient, and while it may seem like they can bounce back from anything there are some medical emergencies that often strike children and need immediate attention.

When working in an environment with children present, it is vital that someone can recognise these conditions and be able to act decisively and confidently to put treatment in place.