The Prospective, Observational, Multicenter, Major Trauma Transfusion (PROMMTT) Study: Comparative Effectiveness of a Time-Varying Treatment With Competing Risks

OBJECTIVE To relate in-hospital mortality to early transfusion of plasma and/or platelets and to time-varying plasma:red blood cell (RBC) and platelet:RBC ratios. DESIGN Prospective cohort study documenting the timing of transfusions during active resuscitation and patient outcomes. Data were analyzed using time-dependent proportional hazards models. SETTING Ten US level I trauma centers. PATIENTS Adult trauma patients surviving for 30 minutes after admission who received a transfusion of at least 1 unit of RBCs within 6 hours of admission (n = 1245, the original study group) and at least 3 total units (of RBCs, plasma, or platelets) within 24 hours (n = 905, the analysis group). MAIN OUTCOME MEASURE In-hospital mortality. RESULTS Plasma:RBC and platelet:RBC ratios were not constant during the first 24 hours (P