Prehospital whole blood transfusion in traumatic hemorrhagic shock: a systematic review and meta-analysis

Prehospital whole blood (WB) is increasingly used for traumatic hemorrhagic shock due to logistical and physiological advantages. This study synthesized evidence, including recent RCTs, to clarify its clinical efficacy.

Six major databases were searched through May 22, 2026. Eligible studies included RCTs and comparative cohorts of adult patients receiving prehospital WB versus standard care. Primary outcomes were 24-hour and 28/30-day mortality. Data were pooled using random-effects models to calculate risk ratios (RR) and mean differences (MD) with 95% CIs.

Synthesis of six studies (3 RCTs, 3 cohorts) involving 4040 patients (1558 WB; 2482 standard care) showed prehospital WB did not significantly decrease 24-hour mortality (RR 1.00; P = 0.98) or 28/30-day mortality (RR 1.09; P = 0.30). No differences were found in 6-hour or in-hospital mortality. However, WB significantly reduced red blood cell requirements within 24 h of hospital arrival (MD -0.97; P = 0.03), though this secondary signal lost statistical significance during sensitivity analysis. Safety outcomes (ARDS, stroke, thrombotic events) showed no significant differences, although estimates for rare events were imprecise. Certainty of evidence ranged from very low to moderate.

Prehospital WB was not associated with improved short- or long-term survival compared with standard care. A reduction in 24-hour red blood cell transfusion requirements after hospital arrival was observed; however, this secondary finding was highly sensitive to individual study weight and was driven primarily by observational cohorts at serious risk of bias.