Practices associated with ABO‐incompatible platelet transfusions: a BEST Collaborative international survey

BACKGROUND: There is a lack of evidence for guiding the best strategy for ABO selection of platelet (PLT) transfusions. As a baseline for future studies, the BEST Collaborative performed an international survey of current practices in this area. STUDY DESIGN AND METHODS: An international survey was sent via BEST members to transfusion services and hospitals requesting the demographics of the transfused patient population, ABO matching policies, anti-A and anti-B measurements in PLT concentrates (PCs), and practices regarding ABO-incompatible PC transfusions to adult and pediatric patients. RESULTS: We received 126 responses from 14 countries, 59% from Europe. Most of them were from local/community (42%) and university hospitals (39%) serving between 500 and 1500 beds; 50.4% transfused fewer than 1000 PCs per year. One-fifth of respondents (19.4%, mainly local/community hospitals) did not have a written policy for selecting ABO-incompatible PCs. Significant practice variation was reported when ABO-mismatched PLTs were given to adults: for PCs suspended in 100% plasma, 29% to 43% of respondents selected any ABO group available; 52% to 61% selected units with compatible supernatant; and, in the case of minor ABO incompatibility, 43% to 54% did not take any specific action. In contrast if ABO-identical PCs were not available for a pediatric recipient, for PCs resuspended in 100% plasma, 71% to 82% selected PCs so the supernatant plasma would be compatible with patient's red blood cells. CONCLUSION: Considerable practice variation exists when transfusing ABO-incompatible PCs, suggesting an opportunity for research to inform evidence-based practices.