Background: The impact of lowering the platelet (PLT) count threshold for prophylactic PLT transfusion on bleeding and PLT use in allogeneic hematopoietic progenitor cell (HPC) transplant recipients is a matter of debate.
Study design and methods: In 166 patients, randomly assigned to receive prophylactic PLT transfusion at a trigger level less than 10 x 10(9) PLTs per L (T10; n = 79) or less than 30 x 10(9) per L (T30; n = 87), the number of PLT and red blood cell (RBC) transfusions given and the number of hemorrhagic events (WHO Grades 2-4) were recorded.
Results: No significant differences were found between the two groups regarding the clinical outcome variables (i.e., bacteremia, engraftment, graft-vs.-host disease [GVHD], hospital stay, death, and survival) or in the median total number of RBC transfusions given. The incidence, in Group T10 18 percent (14/79) and in Group T30 15 percent (13/87), as well as the type of bleeding were comparable. No deaths were attributed to hemorrhages. The number of PLT units transfused, however, was significantly lower in Group T10 (median, 4; range, 0-32), than in Group T30 (median, 10; range, 0-48; p < 0.001). Apart from the trigger level, the day of engraftment, the presence of acute GVHD, or bacteremia also affected the number of PLT transfusions.
Conclusion: A prophylactic PLT transfusion trigger level of less than 10 x 10(9) PLTs per L instead of less than 30 x 10(9) PLTs per L in allogeneic HPC transplant recipients was found to be safe and resulted in a decreased use of PLTs.