The impact of platelet transfusion in massively transfused trauma patients.

BACKGROUND The impact of platelet transfusion in trauma patients undergoing a massive transfusion (MT) was evaluated. STUDY DESIGN The Institutional Trauma Registry and Blood Bank Database at a Level I trauma center was used to identify all patients requiring an MT (≥10 packed red blood cells [PRBC] within 24 hours of admission). Mortality was evaluated according to 4 apheresis platelet (aPLT):PRBC ratios: Low ratio (<1:18), medium ratio (≥1:18 and <1:12), high ratio (≥1:12 and <1:6), and highest ratio (≥1:6). RESULTS Of 32,289 trauma patients, a total of 657 (2.0%) required an MT. At 24 hours, 171 patients (26.0%) received a low ratio, 77 (11.7%) a medium ratio, 249 (37.9%) a high ratio, and 160 (24.4%) the highest ratio of aPLT:PRBC. After correcting for differences between groups, the mortality at 24 hours increased in a stepwise fashion with decreasing aPLT:PRBC ratio. Using the highest ratio group as a reference, the adjusted relative risk of death was 1.67 (adjusted p = 0.054) for the high ratio group, 2.28 (adjusted p = 0.013) for the medium ratio group, and 5.51 (adjusted p < 0.001) for the low ratio group. A similar stepwise increase in mortality with decreasing platelet ratio was observed at 12 hours after admission and for overall survival to discharge. After stepwise logistic regression, a high aPLT:PRBC ratio (adjusted p < 0.001) was independently associated with improved survival at 24 hours. CONCLUSIONS For injured patients requiring a massive transfusion, as the apheresis platelet-to-red cell ratio increased, a stepwise improvement in survival was seen. Prospective evaluation of the role of platelet transfusion in massively transfused patients is warranted.