What is the protocol for platelet (PLT) transfusion in patients with thrombocytopenia?

Platelet Transfusion Protocol for Thrombocytopenia

Prophylactic platelet transfusion should be administered when the platelet count falls below 10 × 10^9/L in patients with therapy-induced hypoproliferative thrombocytopenia, with higher thresholds indicated for specific clinical scenarios and procedures. 1

Prophylactic Transfusion Thresholds

Hematologic Malignancies and Bone Marrow Failure

• Transfuse when platelet count is ≤10 × 10^9/L in hospitalized patients with therapy-induced hypoproliferative thrombocytopenia 1
• Standard dose: single apheresis unit or 4-6 pooled whole blood-derived platelet concentrates (containing 3-4 × 10^11 platelets) 1, 2
• Low-dose platelets (half of standard dose) provide similar hemostasis but may require more frequent transfusions 1, 2
• Higher doses do not improve outcomes but reduce transfusion frequency 3, 4
• Outpatients may benefit from more liberal thresholds for practical reasons 5, 2

Special Clinical Circumstances

• Consider higher thresholds (>10 × 10^9/L) in patients with:
  • Active bleeding 1
  • High fever 1
  • Hyperleukocytosis 1
  • Rapid fall in platelet count 1
  • Coagulation abnormalities (e.g., acute promyelocytic leukemia) 1

Invasive Procedures

• Central venous catheter placement: <20 × 10^9/L 1
• Diagnostic lumbar puncture: <50 × 10^9/L 1, 5
• Major elective non-neuraxial surgery: <50 × 10^9/L 1
• Neurosurgery or procedures involving CNS: <80-100 × 10^9/L 5
• Interventional radiology: <20 × 10^9/L for low-risk procedures, <50 × 10^9/L for high-risk procedures 6

Therapeutic Transfusion (Active Bleeding)

• Transfuse when platelet count is <50 × 10^9/L in presence of active bleeding 5, 7
• Consider transfusion despite adequate platelet count if platelet dysfunction is suspected 5
• For severe bleeding, higher platelet counts (>50 × 10^9/L) may be targeted 7

Special Populations

Cardiac Surgery Patients

• Routine prophylactic transfusion is not recommended for non-thrombocytopenic patients undergoing cardiac surgery with cardiopulmonary bypass 1
• Consider platelet transfusion for patients with perioperative bleeding with thrombocytopenia and/or evidence of platelet dysfunction 1

Patients on Antiplatelet Therapy with Intracranial Hemorrhage

• Evidence is insufficient to recommend for or against platelet transfusion 1
• For non-operative intracranial hemorrhage in adults with platelet count >100 × 10^9/L, including those on antiplatelet agents, platelet transfusion is not recommended 6

Management of Refractory Patients

• Consider HLA-matched platelets or crossmatched platelets in patients with alloimmunization 1, 2
• HLA-matched platelets are indicated when patients fail to achieve adequate increments after standard platelet transfusions 1

Common Pitfalls and Caveats

• Platelet transfusion is rarely indicated in immune thrombocytopenia (ITP) due to rapid destruction of transfused platelets 1, 8
• Platelet transfusion is relatively contraindicated in thrombotic thrombocytopenic purpura (TTP) due to risk of precipitating thrombosis 1
• The accuracy of automated counters may be questionable at extremely low platelet counts; consider clinical context and pattern of recent counts 5, 2
• Patients receiving chemotherapy for acute leukemia have higher bleeding risk compared to autologous HSCT recipients 1, 2
• Transfusion at higher platelet count thresholds (20 × 10^9/L or 30 × 10^9/L) has not been shown to significantly reduce bleeding incidence or mortality 1, 2