Association between high ratio of platelet concentrate to red blood cell and survival among massively transfused patients

Although balanced transfusion protocols (platelet concentrate (PC): red blood cell (RBC) = 1:1) are standard for severe trauma, the impact of a higher PC: RBC ratio (> 1:1) on survival remains unclear. This study aimed to investigate the effectiveness of a high PC to RBC among severely injured patients requiring massive transfusion. We performed a retrospective cohort study using the Japan Trauma Data Bank (2019–2023). Adult patients receiving massive transfusion (> = 10 units of RBC) within the first 24 h of injury were included. Patients were classified into high PC (> 1) and low PC groups (< = 1). The primary outcome was 24-hour mortality, analyzed using inverse probability of treatment weighting and modified Poisson regression. Additionally, we performed spline curve analysis to investigate the nonlinear relationship between the PC: RBC ratio and outcome. Among 3,067 patients (mean age 57.1 years, 67.2% male), 934 were in the high PC group and 2,133 in the low PC group. The high PC group had lower 24-hour mortality (8.9% vs. 15.7%). Adjusted analysis showed a significantly lower risk of mortality in the high PC group (risk ratio 0.54; 95% CI 0.43–0.69). A nonlinear analysis suggested that increasing PC: RBC ratio was associated with lower mortality. A high PC: RBC ratio was associated with lower 24-hour mortality in severely injured patients requiring massive transfusion, suggesting that a higher PC strategy may improve outcomes.