LAUSR

Introduction: There is conflicting evidence of the risks and benefits of platelet transfusions after intracerebral hemorrhage (ICH). Current practice does not necessitate the transfusion of ABO matched platelets despite evidence that platelet recovery is suboptimal in patients receiving ABO incompatible platelet transfusions. Hypothesis: We hypothesize that ICH patients receiving compatible platelet transfusions after ICH have better platelet recovery and outcomes compared to those receiving incompatible platelets. Methods: We conducted single-center, prospective cohort study of consecutive ICH patients admitted to a tertiary-referral academic medical center between 2009 and 2016. Spontaneous ICH patients who received 1 platelet transfusion within 24 hours after presentation were analyzed. Subjects were excluded if they had more than 1 platelet transfusion or non-medication related coagulopathy. Linear regression was used to evaluate the association of incompatible platelet transfusions with absolute count increment ([ACI], a continuous measure of platelet change after transfusion), adjusting for time between CBCs. Additional logistic regression analysis was performed to explore associations of ABO incompatible platelet transfusions with clinical outcomes: discharge mortality, poor modified Rankin Scale (mRS 4-6) at discharge and 3 months, after adjusting for ICH score, sex, and race. Results: Of the 135 patients studied, 62% received ABO compatible platelets and 38% incompatible platelet transfusions after ICH. Patients who received incompatible platelets had lower ACI than those who received compatible platelets (median -1 vs 15; standardized Beta=0.181, p=0.042). There was an association between incompatible transfusions and increased odds of discharge mortality (adjusted OR 4.208 [95%CI 1.478-11.985]; p=0.007). Conclusions: The majority of patients received ABO incompatible platelet transfusions, and these patients had worse platelet count recovery, higher mortality, and worse neurologic outcomes at discharge compared to those that received ABO compatible transfusions. Our findings warrant investigation into the impact of ABO compatibility in platelet transfusions and clinical outcomes after ICH.