A patient has received a pre-hospital blood transfusion from medics on the county's air ambulance for the first time.
It means the odds of people surviving significant injury have increased with both the Essex and Herts Air Ambulance charity's helicopters and rapid response vehicles carrying supplies.
A Critical Care Team was able to stabilise a man before he was transferred to The Royal London Hospital's Major Trauma Centre.
Patients who have suffered blood loss were previously given a saline solution, which doesn't carry oxygen or help with clotting of injuries.
EHAAT's helicopters and RRVs carry packed red blood cells of blood group O Negative, meaning they can be used on any patient. When required, this can be given with plasma, the other major component of human blood. Together these form an effective replacement for patients who have lost blood.
The packed red blood cells are supplied daily from The Princess Alexandra Hospital in Harlow and delivered to EHAAT's Airbases at Earls Colne and North Weald. The blood is replaced daily and replenished as required.
Stuart Elms, Clinical Director at EHAAT told BOB fm: "It has taken a lot of work from our partners at Princess Alexandra Hospital and the EVBS to be able to carry blood on board our helicopters and Rapid Response Vehicles.
"We are pleased that their efforts meant we were able to provide this potentially life-saving intervention for this patient."