About the trial

More information about why the study is needed and the potential benefits it may bring.

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Air Ambulance Services across the country attend accidents or incidents in the community to treat patients who are severely injured or unwell. This is a study about Air Ambulance Services giving blood transfusions to patients before they arrive at hospital (pre-hospital) when they have life-threatening bleeding.

We know that early blood transfusion improves the number of patients that survive who are bleeding like this, but the best way to do this and what blood products to use is not clear.

Not all Air Ambulance Services give blood products, but those who do transfuse patients with red blood cells and plasma. These blood products are made from blood donations and come in different treatment bags, with certain requirements for temperature when they are being stored and carried in the helicopters or rapid response cars.

They also have to be given separately, one after the other to the patient. In addition, carrying these blood product bags can add significant weight to the kit bags that the medical teams carry.

About this study

This study will look at whether giving another product instead of red blood cells and plasma will be better at reducing the number of deaths 24 hours after injury, and reduce the need for further large blood transfusions when patients get to hospital.

This product is called whole blood (WB). It contains red blood cells, plasma and platelets (which help with clotting) all in one bag.

Although there is some evidence of benefit with the use of WB, there have been no studies exploring the clinical and cost effectiveness of pre-hospital administration of WB versus the standard care for bleeding trauma patients in the UK setting.

In 2019, NHS Blood and Transplant carried out a survey of UK Air Ambulance Services and their thoughts about giving WB to patients. In this survey, 82% said that WB would be their preferred blood component, followed by red cells and plasma in one bag (65%), and red blood cells and thawed plasma and platelets (in different bags) (30%). All those who responded said that they would like to see a clinical trial being carried out, before it was given widely in the NHS and would support this work. 

What we are hoping to find

It is important for patients, healthcare professionals and blood services that the clinical and cost effectiveness of pre-hospital WB transfusion is looked at in a large trial before it is rolled out in the NHS, as we have a unique national health service in the UK.

The production of WB could potentially affect the supply of blood components required to treat other patients, as a unit of WB cannot be used to then manufacture other components.

However, it could also be argued that early transfusion of WB may reduce the need for further blood transfusions when patients arrive at hospital, due to earlier control of their bleeding. The study will allow us to look at all these uncertainties.  

We expect the study will start in December 2022 and last for two years.

If you have any queries about the study, you can contact the team at SWIFT@nhsbt.nhs.uk.