Sudden cardiac deaths affect nearly 400,000 people per year in Europe, and every day in the U.S. more than 1,200 people die from cardiac arrest before they reach hospital. In most cases, sudden cardiac arrest is due to ventricular fibrillation, a rapid, irregular twitching of the ventricles of the heart, which can be stopped by applying a defibrillator and delivering an electric shock within 1 minute of its onset. Automated external defibrillators are becoming increasingly common in airplanes, airports, companies, schools and other public places.
Stefan Beckers and colleagues from the University Hospital in Aachen, Germany, asked over two hundred first year medical students with no prior experience to use a defibrillator on a mannequin on two occasions, with a one-week interval between the sessions. Before the second session, the students attended a 15-minute talk on the purpose of the defibrillator, why it has to be used within the first minute of the arrest, and the importance of correct electrode pad positioning. Their response times were monitored during both sessions.
The study shows that 85.6% of the students could position the electrode pads correctly the first time that they tried. During the second session, the proportion increased to 92.8%. The time taken to apply the shock was 85 seconds during the first session, and decreased dramatically to around 59 seconds during the second.
The authors conclude that untrained laypersons are able to use automated external defibrillators quickly and safely. Their performance significantly improves after basic theoretical explanation of the device.