Blood Product Component with Highest Risk for TRALI
Fresh frozen plasma (FFP) poses the highest risk for transfusion-related acute lung injury (TRALI) due to its high plasma volume and potential for containing leukocyte antibodies.
Understanding TRALI Risk by Blood Component
TRALI is one of the most serious complications of blood transfusion, characterized by non-cardiogenic pulmonary edema occurring within 6 hours of transfusion. The risk varies significantly by blood component:
Plasma-Containing Products
- Fresh frozen plasma (FFP) has been identified as the blood component with the highest risk for causing TRALI 1
- The implementation of male-only plasma for component therapy in the UK beginning in 2003 significantly reduced TRALI incidence, confirming plasma's high-risk status 1
- FFP and platelet concentrates are the most frequently implicated blood products in TRALI 1, 2
Risk Factors and Mechanisms
- TRALI is primarily caused by donor antibodies interacting with recipient antigens 3, 4
- Multiparous women are the most frequent source of antibody-containing components that cause TRALI 2, 5
- These antibodies are typically HLA class I and II and/or granulocyte-specific (HNA) 2
- In 50-85% of TRALI cases, leukocyte antibodies are identified in the implicated blood components 2, 4
Risk Mitigation Strategies
Blood banks have implemented several strategies to reduce TRALI risk:
- Using male-only plasma donors or testing female donors for leukocyte antibodies 3, 5
- In Germany since 2009, only plasma from female donors without history of pregnancy or negative testing for antibodies against HLA I, II or HNA has been used, resulting in no TRALI-related deaths since implementation 5
- Multicomponent apheresis collection has been employed to reduce the risk 2
- The use of platelet additive solutions has been associated with reduced TRALI incidence for buffy coat-derived platelet concentrates 6
Clinical Considerations and High-Risk Patients
Certain patient populations appear to be at higher risk for developing TRALI:
- Patients with postpartum hemorrhage, acute myeloid leukemia, liver transplantation, hematopoietic stem cell transplantation, polytrauma, and thrombotic microangiopathy 6
- Patients receiving plasma exchange therapy, such as for thrombotic thrombocytopenic purpura, are particularly vulnerable 7
Differential Diagnosis
- TRALI must be differentiated from transfusion-associated circulatory overload (TACO), which is now the most common cause of transfusion-related mortality 3
- TRALI presents with non-cardiogenic pulmonary edema 1-2 hours after transfusion, with features including hypoxemia, fever, dyspnea, and fluid in the endotracheal tube 3
- TACO presents with respiratory distress within hours of transfusion but is characterized by fluid overload and cardiovascular changes 3
Management of Suspected TRALI
When TRALI is suspected:
- Immediately cease the transfusion 3
- Provide critical care supportive measures and oxygen therapy 3
- Report the case to the blood bank for investigation of donors and deferral if antibodies are identified 7
- Avoid diuretics, which are ineffective for TRALI (unlike TACO) 1, 5
- Consider glucocorticoids, though their use remains controversial 5