'Code Red' for blood transfusion trial

Clinical trials are being conducted in the UK and abroad of new blood transfusion procedures for patients with traumatic injuries.

The aim is to assess whether changing the mix of blood components given to patients can improve their survival chances.

Here, Dr Anne Weaver, lead clinician with London's Air Ambulance, external service, explains what 'Code Red' means, and how they are using it to ensure trauma patients get the right blood mix as quickly as possible.

She also talks of plans to start carrying blood on board the service's only helicopter.