Blood Product Most Frequently Implicated in Fatal TRALI Cases Reported to FDA Prior to 2007
Fresh frozen plasma (FFP) is the single type of blood product most frequently implicated in fatal cases of transfusion-related acute lung injury (TRALI) reported to the FDA prior to 2007.
Evidence Supporting FFP as Primary Culprit in Fatal TRALI
The evidence clearly identifies FFP as the most common blood product associated with fatal TRALI cases:
A retrospective review of fatalities caused by TRALI over a 5-year period (1997-2002) reported to the Center for Biologics Evaluation and Research found that FFP was implicated in one-half of all fatal TRALI cases, while red blood cells were involved in approximately one-third of cases 1.
FFP and platelet concentrates are consistently identified as the most frequently implicated blood products in TRALI 2, 3. Among these, FFP has been documented as having the highest association with fatal outcomes.
The European guidelines on management of bleeding following major trauma specifically note that "FFP and platelet concentrates appear to be the most frequently implicated blood products in transfusion-related acute lung injury" 2.
Pathophysiology of FFP-Associated TRALI
The higher incidence of TRALI with FFP can be explained by several factors:
FFP contains higher concentrations of donor antibodies compared to other blood products. These antibodies (particularly anti-HLA and anti-neutrophil antibodies) are primary mediators in the pathogenesis of TRALI 4.
Female donors with previous pregnancies frequently have HLA antibodies (overall prevalence of 24%), with increasing prevalence related to the number of previous pregnancies 4. Historically, a significant portion of FFP came from female donors.
The "two-hit" mechanism of TRALI involves:
- A predisposing inflammatory condition in the recipient
- The passive transfer of neutrophil or HLA antibodies from the donor plasma 5
Epidemiology and Risk Reduction
The frequency of reported TRALI/possible TRALI cases has been documented as 1:22,500 for FFP compared to 1:82,000 for red blood cells 6, highlighting the significantly higher risk associated with FFP.
Recognition of the role of anti-leukocyte antibodies has led to new strategies to reduce TRALI risk, including policies to produce plasma components primarily from male donors 4, 3.
Implementation of male-only plasma policies has shown a positive impact on reducing TRALI incidence 6.
Clinical Presentation and Management
TRALI typically presents with:
- Acute respiratory distress
- Hypoxemia
- Non-cardiac pulmonary edema within 6 hours of transfusion
- Bilateral pulmonary infiltrates on chest imaging
The fatality rate of TRALI has been reported to be 5-25%, making it one of the leading causes of transfusion-related mortality 7, 4.
Answer to Multiple Choice Question
Based on the evidence presented, the correct answer is: A. Fresh, frozen plasma
This conclusion is supported by multiple studies and guidelines that consistently identify FFP as the blood product most frequently implicated in fatal TRALI cases reported to the FDA prior to 2007.