Factors related to the outcome of prophylactic platelet transfusions in patients with hematologic malignancies: an observational study

BACKGROUND A better knowledge of the connections between platelet concentrate (PC) characteristics and transfusion outcomes in day‐to‐day practice would help improve the selection process of the most appropriate PC. STUDY DESIGN AND METHODS In this study of prophylactic platelet transfusions in patients with hematologic malignancies between 2002 and 2012, outcome criteria were corrected count increments (CCIs) and platelet transfusion intervals (TIs, in days). Studied characteristics were ABO matching status, platelet source, dose, storage duration, irradiation, washing, and transfusion sequence number (TSN). The analysis consisted of multivariable linear mixed‐effects models with adjustments for patient diagnosis, sex, and type of treatment. RESULTS Overall, 869 patients and 6662 platelet transfusions were analyzed. For each day after the second day of storage, the CCI and TI decreased by 0.88 and 0.06 day, respectively. Compared to ABO‐identical, transfusion with major ABO‐incompatible PCs decreased the CCI and TI by 0.79 and 0.21 day, respectively. Platelet washing reduced the CCI and TI by 2.28 and 0.24 day, respectively. There was no significant association between platelet source or irradiation and CCI or TI. TI increased as the platelet dose per kg increased. Both CCI and TI decreased as the TSN increased. CONCLUSION Transfusion outcomes were significantly related to several PC‐related factors. Associations for ABO matching status and storage duration were stronger than previously reported. Taking into account such factors when selecting a PC for transfusion could be beneficial to the recipient.