Development of a centralised national AED (automated external defibrillator) network across all ambulance services in the United Kingdom.

Background: Early cardiopulmonary resuscitation and defibrillation is key to increasing survival following an out-of-hospital-cardiac-arrest (OHCA). However, automated external defibrillators (AEDs) are used in a very small percentage of cases. Despite large numbers of AEDs in the community, the absence of a unified system for registering their locations across the UK's ambulance services may have resulted in missed opportunities to save lives. Therefore, representatives from the resuscitation community worked alongside ambulance services to develop a single repository for data on the location of AEDs in the UK. Methods: A national defibrillator network, "The Circuit", was developed by the British Heart Foundation in collaboration with the Association of Ambulance Chief Executives, the UK ambulance services, the Resuscitation Council UK and St John Ambulance. The database allows individuals or organisations to record information about AED location, accessibility, and availability. The database synchronises with ambulance computer aided dispatch systems to provide UK ambulance services with real-time information on the nearest, available AED. Results: The Circuit was successfully rolled out to all 14 UK ambulance services. Since 2019, 82,108 AEDs have been registered. Of the AED data collected by The Circuit, 54% were not previously registered to any ambulance service, and are therefore new registrations. Conclusion: The Circuit provides ambulance services with a single point of access to AED locations in the UK. Since the launch of the system the number of defibrillators registered has doubled. Linking the Circuit data with patient outcome data will help understand whether improving the accessibility to AEDs is associated with increased survival.