ABO-identical versus incompatible platelet transfusion in patients with intracranial hemorrhage

Patients with spontaneous and traumatic intracranial hemorrhage (ICH) are frequently transfused platelets to treat thrombocytopenia, platelet function defects, and reverse antiplatelet drugs. ABO-identical platelet transfusion has been suggested to lead to higher post-transfusion platelet increments compared to major-ABO incompatible transfusion. We hypothesized that patients who received ABO-identical transfusion would have higher post-transfusion platelet increments and superior neurologic outcomes.

Adults with traumatic or non-traumatic ICH from January 1st 2018 to December 31st 2022 were identified using electronic medical records and international classification of disease (ICD)-10 codes. Patients were excluded if they lacked a platelet count within 24 hours before and within 24 hours after transfusion or if they received multiple platelet transfusions before their platelet count was remeasured. After stratification by ABO-identical, ABO-major incompatible, and ABO-minor incompatible transfusion, post transfusion increments were compared, as were clinical outcomes.

Among 167 patients who received platelet transfusion, 76 (45.5%) received ABO-identical transfusion, 54 (32.3%) received ABO-major incompatible transfusion, and 37 (22.2%) received ABO-minor incompatible transfusion. There were no significant differences in absolute platelet increment between groups. The median increment was 7x109/L for ABO-identical platelets, 10x109/L for ABO-major incompatible platelets, and 11x109/L for ABO-minor incompatible platelets, p = .87. There was no significant difference in the percentage of patients discharged alive with modified Rankin score of 1 or 2 or cerebral performance category 1 or 2 between groups (p = .56 and .39 respectively). After adjusting for confounders in a general linear model there remained no associations between ABO compatibility and platelet increment after transfusion.

Our data support similar efficacy for ABO-identical and ABO-incompatible platelet transfusion in patients with ICH.