Impact of platelet transfusion on outcome, clot dynamics, and platelet function in thrombocytopenic trauma patients

Objectives: Of all trauma patients, 25% require a blood transfusion, of which 2–3% receive a massive transfusion. In severely injured bleeding trauma patients, early platelet administration has been shown to improve hemostasis and decrease mortality. The aim was to compare the changes after platelet transfusion on prothrombin time (PT) and activated partial thromboplastin time (aPTT), platelet function, and clot dynamics in thrombocytopenic trauma patients and to identify independent risk factors for in-hospital mortality. Materials and Methods: Thrombocytopenic trauma patients who received platelets either with/without receipt of other blood components over two years were included in this prospective study. The pre-and post-transfusion platelet count, coagulation profile, clot dynamic analysis assessed by thromboelastography, and platelet function analysis assessed by flow cytometry were compared. The primary outcome was in-hospital mortality. Statistical analysis: Data is summarized as mean±S.D or median (minima-maxima) for continuous variables and for categorical variables data is presented as frequency and percentages. Results: Of the 45 thrombocytopenic trauma patients included in the study, 23 (51.1%) were refractory to platelet transfusion and 14 (31.1%) died. Significant differences were seen in alpha angle ( P = 0.02) and maximum amplitude ( P = 0.01), number of patients with coagulopathy ( P = 0.007), percentage of patients with increased k-time ( P = 0.03), and decreased alpha angle ( P = 0.001) pre- and post-transfusion. The non-survivors had significantly lower post-transfusion PC ( P < 0.001), increased pre- and post-transfusion PT ( P = 0.007 and P = 0.01, respectively), and increased pre-and post-transfusion aPTT ( P = 0.009 and P = 0.002, respectively). No significant differences were observed based on the thrombolelastography and platelet function parameters between survivors and non-survivors. Pre-transfusion aPTT and coagulopathy post-transfusion were independently associated with mortality (odds ratio [OR]: 9.4; 95% confidence interval [CI]: 1.6–54.3; P = 0.01 and OR: 12.6; 95% CI: 1.55–102.9; P = 0.01, respectively). Conclusions: Prothrombin time coagulopathy status, clot kinetics, and clot strength improved after platelet transfusion. Pre-transfusion aPTT and coagulopathy post-transfusion are independent risk factors for death in thrombocytopenic trauma patients. The clinical significance of platelet function analysis and clot dynamics in thrombocytopenic trauma patients undergoing transfusion therapy is yet to be ascertained.