Trends in massive transfusion practice for trauma in Japan from 2011 to 2020: a nationwide inpatient database study

BACKGROUND: Previous studies have reported conflicting results regarding fresh frozen plasma (FFP)-to-red blood cell (RBC) ratio and platelet-to-RBC ratio on outcomes for massive transfusion for trauma. Moreover, nationwide data on massive transfusion practices for trauma in the real-world clinical setting are scarce. This study aimed to examine the nationwide practice patterns and trends in massive transfusion for trauma in Japan using a national administrative, inpatient database. METHOD: We identified patients who underwent emergency hospitalization for trauma and received massive transfusion, defined as administration of at least 20 units of RBC within the first 2 days of admission, using the nationwide inpatient database, which covers approximately 90% of all tertiary emergency hospitals in Japan, between 2011 and 2020. Trends in the incidence and practice patterns of massive transfusion were described by calendar year. The association of practice patterns with mortality or adverse events was tested. RESULTS: A total of 3,530,846 trauma hospitalizations were identified, of which 5247 (0.15%) received massive transfusion. A significant declining trend was observed in the incidence of massive transfusion in trauma hospitalizations from 0.24% in 2011 to 0.10% in 2020 (P for trend < 0.001). The FFP-to-RBC ratio rose significantly from 0.77 in 2011 to 1.08 in 2020 (P for trend < 0.001), while the platelet-to-RBC ratio remained virtually unchanged from 0.71 in 2011 to 0.78 in 2020 (P for trend 0.060). Massive transfusion with lower FFP-to-RBC (< 0.75) and platelets-to-RBC ratio (< 1.00) were associated with increased in-hospital mortality compared with those ≥ 1.00, while there were linear increases in adverse events with increasing FFP and platelets ratios. CONCLUSIONS: This study demonstrated a declining trend in the incidence and a rise in higher FFP-to-RBC ratios in massive transfusion in association with patient outcomes for trauma from 2011 to 2020 in Japan. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40560-023-00685-0.