From the Guidelines
Type and screen testing is generally not required for platelet transfusions. Unlike red blood cell transfusions, platelets can typically be given without ABO compatibility testing because they contain minimal red blood cell content 1. However, ABO-compatible platelets are preferred when available because patients may develop antibodies to incompatible ABO antigens present on platelets, which could reduce transfusion effectiveness. Rh typing may be considered for Rh-negative females of childbearing potential receiving Rh-positive platelets, as they might require Rh immunoglobulin to prevent sensitization. The primary concern with platelet transfusions is ensuring appropriate clinical indication (such as thrombocytopenia or platelet dysfunction with bleeding) rather than compatibility testing.
Some key points to consider when deciding on platelet transfusion include:
- Platelet count is the main laboratory measurement used to guide platelet transfusion, but it provides no qualitative information about platelet hemostatic function 1.
- The ideal approach to platelet transfusion would be to administer sufficient platelets to optimize patient outcomes while avoiding unnecessary transfusions with their attendant risks and costs 1.
- Platelets are typically transfused as either random donor platelet concentrates or single-donor apheresis platelets, with each adult dose expected to increase the platelet count by approximately 30,000-60,000/μL.
Overall, the decision to transfuse platelets should be based on the patient's clinical condition and the potential benefits and risks of the transfusion, rather than on the need for type and screen testing. The focus should be on ensuring appropriate clinical indication and minimizing unnecessary transfusions, rather than on compatibility testing 1.
From the Research
Platelet Transfusion Requirements
To determine if typing and screening are necessary for a platelet transfusion, several factors must be considered:
- The importance of ABO matching in platelet transfusion [(2,3,4,5)]
- The impact of ABO incompatibility on platelet count increments [(3,4,5)]
- The risk of hemolysis associated with minor ABO incompatibility 6
- The risk of RhD alloimmunization when RhD-negative patients receive platelets obtained from RhD-positive donors 6
ABO Matching Considerations
ABO matching is crucial for platelet transfusion, as it can affect the platelet count increment and the risk of refractoriness:
- ABO-identical platelets result in higher platelet count increments compared to ABO-nonidentical platelets [(3,4,5)]
- ABO-incompatible plasma can lead to the formation of immune complexes that can destroy compatible platelets 3
- The effects of ABO-nonidentical transfusions are cumulative and can affect the success of subsequent identical transfusions 3
Typing and Screening Requirements
Based on the available evidence, typing and screening for ABO and RhD are necessary for platelet transfusion to ensure compatibility and minimize the risk of adverse reactions:
- ABO typing is essential to prevent ABO-incompatible transfusions, which can result in lower platelet count increments and increased risk of refractoriness [(2,3,4,5)]
- RhD typing is necessary to prevent RhD alloimmunization in RhD-negative recipients 6
- Screening for ABO and RhD antibodies is also crucial to identify potential incompatibilities and prevent adverse reactions 6