ABO Compatibility for Platelet Transfusions
Introduction to ABO Compatibility
- The American Society of Clinical Oncology recommends that ABO-compatible products should be provided whenever possible to optimize platelet increments and minimize hemolysis risk 1
- Transfusing ABO-identical or ABO-compatible platelets is preferred whenever inventory allows 1
Practical Approach to ABO Selection
- Red cell cross-matching is not required for platelet products due to minimal red cell content 2, 1
- ABO-compatible products optimize post-transfusion platelet count increments and reduce complications 3, 4
Impact of ABO Incompatibility
- ABO incompatibility can compromise post-transfusion increments, particularly when assessing platelet refractoriness 3, 4, 5
- When diagnosing platelet refractoriness, use at least two ABO-compatible transfusions stored less than 72 hours to accurately assess whether poor increments are due to alloimmunization versus ABO mismatch 3, 4, 6
- Incompatible plasma from platelet transfusions can cause hemolysis, particularly in children 2, 1
Critical Clinical Scenarios
- ABO compatibility is essential when evaluating refractoriness 3, 4, 5, 7
- Refractoriness should only be diagnosed after at least two ABO-compatible transfusions (stored <72 hours) result in poor increments (CCI <5,000 or absolute increment <2,000/unit) 3, 5, 7
- The platelet concentrate transfused must be ABO-identical or at least ABO-compatible to provide good yield in trauma patients requiring massive transfusion 8
Common Pitfalls to Avoid
- Do not diagnose platelet refractoriness based on ABO-incompatible transfusions 3, 4, 6
- Exercise greater caution with ABO-incompatible platelets in children due to higher hemolysis risk from incompatible plasma 2, 1