Air Ambulances begin trial transfusing ‘whole blood’ to potentially improve civilian and military trauma care

14 December 2022

A new clinical trial begins tomorrow (15 December) with Air Ambulance crews carrying ‘whole blood’ instead of separate red blood cells and plasma for the treatment of severely injured patients at risk of bleeding to death.

The SWIFT (1) trial is led by NHS Blood and Transplant (NHSBT) and will involve 10 air ambulance charities across the country in partnership with the Ministry of Defence and Air Ambulances UK.

If the trial shows patient benefit, it could reduce trauma deaths in civilian accidents and also on the battlefield, and in any situation where delaying a transfusion by seconds or minutes could be critical.

Why is this trial needed?

Air Ambulances have carried red blood cells since 2012. However during the SWIFT trial they will also carry ‘whole blood’. This is blood as it taken from the arm of a donor. It includes all the different blood components together, such as red blood cells, plasma, and platelets (2).

Previous studies, including on military casualties in Afghanistan, have indicated whole blood could have better outcomes for trauma patients, including a greater chance of survival.

Whole blood may work better because it contains platelets. Platelets are the cell fragments which help the blood to clot. Platelets are difficult to store – they have a short five-day shelf life, must be stored between 20C and 24C, and need constant gentle movement to help them stay oxygenated. This means they are very difficult to use outside of hospitals. Currently, Air Ambulance patients, and soldiers needing battlefield transfusions, can receive plasma and red blood cells, but not platelets.

Additionally, carrying and transfusing one blood product could also be lighter and simpler. It could enable faster treatment, at a time when every minute counts. And it could make the transfusion process easier and reduce risk, a crucial benefit in difficult and fast-moving incidents.

There is already past evidence that whole blood could lead to reduced mortality and reduce the amount of blood needed after patients arrive at hospital (3). However, only a full randomised controlled trial such as SWIFT can provide the definitive answers.

Ollie's story

Ollie Berry was aged 16 when he needed life-saving blood and plasma transfusions by Great Western Air Ambulance Charity.

Ollie and mum Rachel with the Air Ambulance teamHe suffered liver damage and lost around six units of blood after being in collision with a van while riding his bike in June 2019.

The Air Ambulance team said they had no doubt that without this Ollie would not have survived. He was taken to Southmead Major Trauma Unit in Bristol where he spent weeks in intensive care. Ollie, now aged 19, is well and works as a trainee manager.

Mum Rachel James, 47, of St Braivels, near Chepstow in Gloucestershire, said: “He was urgently given all the blood products they carried.

“Ollie has always been aware and that he is here today due to the blood and plasma provided by generous donors and the amazing team that worked on him. Every minute counted.

“I really hope the new trial will work and that more lives can continue to be saved through using whole blood transfusions.”

What will the trial involve?

All of the blood used will come from group O Rh negative donors. This is the ‘universal donor’ blood type which is vital in emergency trauma care, when there is not time to check the patient’s blood type before transfusion is started.

Funding for the trial has been provided by NHSBT, the Air Ambulance charities, and the Ministry of Defence. The trial goes live tomorrow with the London Air Ambulance and will be rolled out to nine more Air Ambulance Services across the country over the next few months. The full list of air ambulance charities who are taking part in SWIFT is:

  • Air Ambulance Kent Surrey Sussex  
  • Dorset and Somerset Air Ambulance 
  • Essex and Herts Air Ambulance 
  • Great North Air Ambulance 
  • Great Western Air Ambulance 
  • Hampshire and Isle of Wight Air Ambulance 
  • London’s Air Ambulance 
  • Magpas Air Ambulance 
  • North West Air Ambulance
  • Thames Valley Air Ambulance

Over a two-year period, SWIFT will recruit 848 patients. One group of patients will continue to be given transfusions of red blood cells and plasma separately, with platelets given if needed after arrival at hospital. The other group of patients will receive transfusions of whole blood. The trial will compare survival and the amount of blood needed over the first 24 hours after injury.

Further improving trauma care would be of major importance. Major trauma kills more than 5,400 people every year in the UK. Pre-hospital red blood cell transfusions already save lives, with studies in military and civilian settings reporting a 12-14% absolute reduction in 30-day mortality (4). This trial could enable a further reduction in mortality.

You can register to give blood online or by calling 0300 123 23 23.


  • Ollie and Mum Rachel with the Air Ambulance team

Article notes

  1. SWIFT stands for Study of Whole blood In Frontline Trauma.
  2. Red blood cells carry oxygen around the body. Plasma is the liquid part of your blood and it contains proteins which help blood to clot. Platelets are cell fragments that are essential for blood clot formation.
  3. Spinella, P.C., et al. Warm fresh whole blood is independently associated with improved survival for patients with combat-related traumatic injuries. s.l. : J Trauma, 2009. Cotton, B.A., et al. A randomized controlled pilot trial of modified whole blood versus component therapy in severely injured patients requiring large volume transfusions. s.l. : Ann Surg, 2013. Yazer, M.H., et al. Initial safety and feasibility of cold-stored uncrossmatched whole blood transfusion in civillian trauma patients. s.l. : J Trauma Acute Care Surg, 2016. Perkins, J.G., et al. Comparison of platelet transfusion as fresh whole blood versus apheresis platelets for massively transfused combat trauma patients (CME). s.l. : Transfusion, 2011.
  4. Major Trauma Care in England: report by the Controller and Auditor General. s.l. : National Audit Office, 2010. Shackelford, S.A., et al. Assosciation of prehospital Blood Product Transfusion During Medical Evacuation of Combat Casualties in Afghanistan With Acute and 30-Day Survival. s.l. : JAMA, 2017. Griggs, J.E., et al. Mortality of civilian patients with suspected traumatic haemorrhage receiving pre-hospital transfusion of packed red blood cells compared to pre-hospital crystalloid. s.l. : Sc and J Trauma Resusc Emergency Med, 2018.

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