After a call is received in the 999 ambulance control room, verified volunteers registered with the app are alerted to incidents taking place within 500 meters of their location.

GoodSAM, which stands for ‘Good Smartphone Activated Medics', uses mobile GPS technology to notify the nearest available responder of an incident. These responders can then begin CPR before an ambulance arrives.

The early delivery of CPR and defibrillation is critical in improving survival rates from cardiac arrest. Every minute without intervention reduces the chance of survival by up to 10%.

The first phase of the service went live across the Isle of Wight and South Central Ambulance Service's operating areas in June, with certified healthcare professionals and clinically trained individuals being able to register. The aim is to then open it up to trained public volunteers from the autumn.

David Hamer, operations manager for SCAS, said: ‘The launch of GoodSAM is a significant milestone in our mission to improve survival from cardiac arrest. By enabling trained responders to reach patients faster, we can dramatically increase the chances of a positive outcome. This is about saving lives, and we are proud to be part of this initiative.'

Louise Walker, head of education and community response for Isle of Wight NHS Ambulance Service, added: ‘Every second counts when a person is having a cardiac arrest, so the ability to activate volunteer trained responders in our local community will help save many more lives across the Island.

'We are so grateful to all GoodSAM responders for helping us to build a stronger, more responsive community network.'

The project has been partly funded by South Central Ambulance Charity who support SCAS in enhancing emergency care.