Pre-hospital blood transfusion in non-traumatic major haemorrhage: a retrospective observational study.

BACKGROUND: Blood component administration for major traumatic haemorrhage is established clinical practice in pre-hospital emergency medicine. However, transfusion practices for non-traumatic haemorrhage lack specific guidance. We analysed historical data on non-traumatic major haemorrhage to describe the incidence and current blood product administration practices. METHOD: This retrospective observational cohort study reviewed Air Ambulance Charity Kent Surrey Sussex patient data from 11 November 2013 to 9 August 2024. The cohort included patients receiving pre-hospital blood components for non-traumatic major haemorrhage. Data included demographics, haemorrhage aetiology, physiology, transfusion volumes, cardiac arrest incidence, and intra-arrest transfusion. RESULTS: Fifty patients were identified, median age was 48 years (IQR 32-64). Gastrointestinal (GI) bleeding was most common (n = 21). Mean presenting systolic blood pressure (SBP) triggering transfusion was 79 mmHg. High-risk bleeding characteristics such as abdominal aortic anneursym required substantial transfusion volumes (median 4 units packed red blood cells). Pre-transfusion shock index significantly improved from 1.39 to 0.97 post-transfusion (p < 0.001). CONCLUSION: Pre-hospital blood transfusion improved patient physiology in our cohort of non-traumatic haemorrhage patients. Patients with non-traumatic haemorrhage may benefit from a pre-hospital transfusion.