Abstract
BACKGROUND: Transfusion-related acute lung injury (TRALI) remains a leading cause of transfusion-associated mortality in the United States. Donor-based mitigation has reduced TRALI risk from plasma and apheresis platelets, but the residual risk associated with whole-blood-derived pooled platelets is not well defined. STUDY DESIGN AND METHODS: We retrospectively analyzed transfusion reactions reported to the American Red Cross (ARC) national hemovigilance program from 1 January 2006 through 31 December 2023. Reactions were adjudicated using Canadian Consensus Conference criteria; definite or highly probable TRALI cases (levels 5-6) were included. Component distribution data served as denominators. Trends were evaluated in relation to two mitigation efforts: male-predominant plasma (2005-2006) and HLA-antibody screening of previously pregnant apheresis-platelet donors (2016). RESULTS: Over 18 years ARC distributed 92.7 million red blood cells, 23.5 million plasma units, and 17 million platelets-including 0.87 million pooled WB-derived platelets, 11.7 million plasma-suspended apheresis, 1.5 million PAS apheresis, and 2.9 million pathogen-reduced (PR) platelet-additive solution-3 (PAS) apheresis platelets. We identified 393 high-probability TRALI cases. Plasma-associated TRALI declined from 20.0 to <4 cases per million units following male-predominant policies; RBC risk remained stable (0.7-4.3/million). TRALI incidence for whole blood pooled platelets averaged 13.5/million, exceeding plasma-suspended (4.4/million), PAS (0.8/million), and PLT PR PAS (0.5/million) apheresis platelets (p = .002 for differences among apheresis subtypes). Compared to apheresis PLT, the TRALI incidence for whole blood PLTS is increased by about 9-13/million. CONCLUSION: Current mitigation strategies, which are not required for whole blood derived platelets in the United States, have substantially reduced TRALI risk from apheresis platelets. If whole blood-pooled platelets production in the United States increases, consideration should be given to the addition of mitigation strategies-such as male-predominant pooling and donor antibody screening-to align their safety profile.