A recently published prospective cohort study of ten level I trauma centers in the US suggests that increased ratios of plasma: red blood cells (RBC) and platelets:RBCs were independently associated with decreased mortality within 6 hours of admission. Led by Dr. John Holcomb of the University of Texas Health Science Center, the study enrolled 905 adult trauma patients who survived at least 30 minutes after admission and received at least 1 unit of RBCs within six hours of admission and at least three units of RBCs within 24 hours. Using a time-dependent model, researchers assessed the association of increased plasma and platelet ratios on in-hospital mortality. Within the first six hours, patients with ratios of less than 1:2 were found to be 3 to 4 times more likely to die than patients with ratios of 1:1. During the first six hours, the majority of mortality was attributed to hemorrhage. No association between plasma:RBC or platelet:RBC ratios and mortality was observed after 24 hours of admission, when the majority of mortality was attributed to non-hemorrhagic causes.
1. Holcomb JB, Del Junco DJ, Fox EE, Wade CE, Cohen MJ, Schreiber MA, Alarcon LH, Bai Y, Brasel KJ, Bulger EM, Cotton BA, Matijevic N, Muskat P, Myers JG, Phelan HA, White CE, Zhang J, Rahbar MH; for the PROMMTT Study Group. The Prospective, Observational, Multicenter, Major Trauma Transfusion (PROMMTT) Study: Comparative Effectiveness of a Time-Varying Treatment With Competing Risks. Arch Surg. 2012 Oct 15:1-10. doi: 10.1001/2013.jamasurg.387.