Aims/Objectives/Background It is thought that administering pre-hospital blood products (PHBP) in traumatic haemorrhagic shock can increase survival. The resuscitation with Pre-Hospital Blood Products (RePHILL trial) was a multi-centre, randomised controlled trial of pre-hospital blood product administration versus standard care for traumatic haemorrhage designed to answer this question. In 2016 less than half of all air ambulance services (AAS) in the United Kingdom (UK) carried PHBP. In 2019 this number had increased to 18/22 AAS. The aim of this survey was to review the current use of PHBP by AAS in the UK prior to publication of the RePHILL trial.

Methods/Design On the 21^st April 2021, all UK AAS were emailed using the contact address published on their website with a standardised email asking about their current use of PHBP. AAS who did not reply were followed up with a second email three weeks later. Complete non-responders had their websites searched for blood product terms to see if the service reported their use.

Results/Conclusions 17 out of 22 AAS replied to the survey. Information was extracted from a further three AAS websites. 17 AAS reported carrying packed red blood cells, seven carried fresh frozen plasma, six carried Lyoplas, two carried fibrinogen and one carried Beriplex. No AAS reported carrying platelets. Two AAS reported not carrying any PHBP.

In 2016 less than half of UK ASS carried PHBP, now almost every service is adopting their use. To have widespread practice changes such as this over the last five years demonstrates how quickly the field of pre-hospital emergency medicine is evolving. Carrying PHBP brings a cost to services and risk to patients. If the RePHILL trial fails to demonstrate an outcome benefit from PHBP once published, it will be interesting to see whether AAS continue to employ a PHBP model for traumatic haemorrhage resuscitation.