The changes include the introduction of a new purple category for cardiac and respiratory arrests and a red emergency category for major trauma and other incidents where a person is at significant risk of experiencing a cardiac or respiratory arrest if they do not receive a rapid response.

Health secretary Jeremy Miles said: ‘We want to save more lives and improve the chances of people surviving cardiac arrests in Wales.

‘The current system treats someone in cardiac arrest the same as someone with generalised breathing difficulties who can often be treated safely at home. These changes will ensure ambulance clinicians reach those with the greatest need first, while making sure everyone gets the right care based on their clinical needs.'

The changes are modelled on the approach used in Ireland, Scotland and Australia where survival rates and outcomes have improved as a result.

It is expected ambulances will respond to 999 calls in both new categories within an average of six to eight minutes.

The new approach aims to improve survival rates for cardiac arrests experienced outside of hospital in Wales, which currently stand at less than 5%.

For purple category calls, the primary measure will be the percentage of people to have a heartbeat restored after a period of cardiac arrest which is subsequently retained until arrival at hospital. The expectation will be that this will continuously increase over time.

It will also be recorded where timely action is shown to improve outcomes, such as the average time it takes for receipt of bystander CPR and defibrillation following an out-of-hospital cardiac arrest.