Platelet Transfusions in Hematopoietic Stem Cell Transplantation (The PATH III Trial)

Inclusion Criteria: 1. Adults 18 years or older undergoing ASCT for a hematologic malignancy 2. Patients providing written informed consent prior to starting transplantation Exclusion Criteria: 1. A previous WHO grade 2, 3 or 4 bleeding event within the past year 2. A previous or current unprovoked thrombotic event defined as a pulmonary embolism, deep vein thrombosis, cerebral thrombosis 3. A current provoked thrombotic event (e.g. catheter-related thrombosis) within last month and/or still requiring anticoagulant treatment. 4. A requirement for therapeutic anticoagulant or anti-platelet drugs during ASCT 5. Active angina (chest pain of presumed cardiac origin either at rest or with activity) 6. Current or previous (within 2 weeks) urinary tract bleeding 7. An inherited hemostatic or thrombotic disorder 8. Coagulopathy defined as a prothrombin time '/International Normalization Ratio (INR) or activated partial thromboplastin time more than 1.5 times the upper limit of normal or fibrinogen less than 2 g/L 9. Previously documented history of refractoriness to platelet transfusion secondary to HLA antibodies (Refractoriness is defined as 2 consecutive ABO matched platelet transfusions with platelet increment of \< 7.5 and the presence of anti-HLA antibodies) 10. Significant renal impairment (creatinine more than 1.5 times the upper limit of normal or a eGFR less than 0.5 mL/min/1.78m2) 11. Pregnant or breast-feeding 12. Unwilling or unable to provide informed consent 13. Participant has acquired disturbances to his/her colour vision (does not apply to congenital colour blindness) 14. Participant has known sensitivity or allergy to Tranexamic Acid or any of its ingredients