From the Guidelines
Platelets should be transfused in hospitalized adult patients with a platelet count of 10 × 10^9 cells/L or less to reduce the risk for spontaneous bleeding. This recommendation is based on the strongest and most recent evidence from the AABB clinical practice guideline published in the Annals of Internal Medicine 1. The guideline suggests that transfusing up to a single apheresis unit or equivalent is sufficient, as greater doses are not more effective, and lower doses equal to one half of a standard apheresis unit are equally effective.
Key Considerations for Platelet Transfusion
- The AABB recommends prophylactic platelet transfusion for patients having elective central venous catheter placement with a platelet count less than 20 × 10^9 cells/L 1.
- For patients having elective diagnostic lumbar puncture or major elective nonneuraxial surgery, prophylactic platelet transfusion is suggested with a platelet count less than 50 × 10^9 cells/L 1.
- Routine prophylactic platelet transfusion is not recommended for patients who are nonthrombocytopenic and have cardiac surgery with cardiopulmonary bypass, but platelet transfusion may be considered for patients exhibiting perioperative bleeding with thrombocytopenia and/or evidence of platelet dysfunction 1.
Clinical Decision-Making
In clinical practice, the decision to transfuse platelets should be individualized based on the patient's risk of bleeding, underlying medical condition, and platelet count. The standard adult dose of one unit of apheresis platelets or a pool of 4-6 units of whole blood-derived platelets can increase the platelet count by 30,000-50,000/μL. ABO compatibility should be considered, and the patient should be monitored for transfusion reactions. By prioritizing the most recent and highest-quality evidence, clinicians can make informed decisions about platelet transfusion to optimize patient outcomes and minimize the risk of bleeding complications.
From the Research
Indications for Platelet Transfusion
- Platelet transfusions are given to prevent bleeding in thrombocytopenic patients undergoing chemotherapy for malignancy or hematopoietic stem cell transplant 2
- The recommended indication for prophylactic transfusion is a platelet count of 10,000/microL 2, 3
- For patients with inherited defects of platelet function or acquired defects, prophylactic transfusion is not recommended, but transfusion may be helpful to treat serious bleeding 2
- In idiopathic thrombocytopenic purpura, platelet survival is short and transfusion is useful only for severe bleeding 2
Thresholds for Platelet Transfusion
- The standard recommendation has been to treat acute hypoproliferative thrombocytopenia with a prophylactic platelet transfusion if the morning platelet count is less than 10,000/μL, or less than 20,000/μL if there are additional risk factors 3
- For chronic thrombocytopenia, transfusion has been recommended if the platelet count is less than 5,000/μL 3
- However, new studies indicate that a more restrictive transfusion strategy is justified, and prophylactic platelet transfusions should be given when clinically indicated in consideration of the individual hemorrhagic risk 3
Alternative Strategies for Platelet Transfusion
- The use of alternative tests for guiding platelet transfusion, such as thrombin generation assays or thromboelastography, is being explored 4
- Innovative approaches for platelet enumeration, such as fluorescent labeling and flow cytometry, are also being developed 4
- Thrombopoietin (TPO) mimetics have been shown to reduce the number of participants receiving any platelet transfusion, but the evidence is of low to moderate quality 5