Laboratory predictors of bleeding, and effect of platelet and RBC transfusions on bleeding outcomes, in the PLADO Trial

Lynne Uhl, Susan F. Assmann, Taye H. Hamza, Ryan W. Harrison, Terry Gernsheimer and Sherrill J. Slichter

Key points

  • Laboratory parameters associated with increased bleeding were platelet counts ≤5,000/µL; hematocrits ≤25%; INR >1.2; and aPTT >30 sec.

  • Platelet and RBC transfusions on days with bleeding are often not sufficient to change bleeding outcomes on the following day.


Bleeding remains a significant problem for many thrombocytopenic hematology/oncology patients in spite of platelet transfusions. Factors that might contribute to bleeding were analyzed for 16,320 patient-days on or after their first platelet transfusion in 1077 adult patients enrolled in the Platelet Dose Trial (PLADO). All patients had greatly increased risk of bleeding at platelet counts of ≤5,000/µl (OR 3.1, 95% CI 2.0-4.8) compared to platelet counts ≥81,000/µL. Platelet counts between 6,000/µl and 80,000/µL were also associated with somewhat elevated bleeding risk in patients receiving allogeneic SCT or chemotherapy, but not in those undergoing autologous SCT. Other significant laboratory predictors of bleeding were hematocrit ≤25% (OR 1.29, CI 1.11-1.49); aPTT of 30 to ≤50 seconds (OR 1.40, CI 1.08-1.81, p=0.01), aPTT >50 sec (OR 2.34, CI 1.54-3.56); INR of 1.2 to 1.5 (OR 1.46, CI 1.17-1.83); and INR >1.5 (OR 2.05, CI 1.43-2.95). Transfusion of either platelets or red cells on days with bleeding was often not sufficient to change bleeding outcomes on the following day. Because bleeding occurred over a wide range of platelet counts among patients undergoing allogeneic stem cell transplant or chemotherapy, and platelet transfusions may not prevent bleeding, other risk factors may be involved. These may include low hematocrit and coagulation abnormalities.

  • Submitted January 17, 2017.
  • Accepted June 27, 2017.