Donor screening as a TRALI risk reduction strategy

Acute lung injury after platelet transfusion in a patient with dengue fever

Transfusion-related acute lung injury (TRALI) is a serious clinical syndrome associated with the transfusion of plasmacontaining blood components. Recently, TRALI has come to be recognized as the leading cause of transfusion-related mortality. This complication typically presents as shortness of breath, hypoxemia, hypotension, fever, and non cardiogenic pulmonary edema, occurring within 6 h after transfusion. Although the mechanism of TRALI has not been exactly known, it has been associated with human leukocyte antigen antibodies and with biologically active mediators in stored cellular blood components. We, hereby, present a case of a patient with dengue fever who developed acute lung injury (ALI), presumably TRALI, after transfusion of platelet concentrates. He was treated with supportive measures and mechanical ventilation. Greater knowledge and increased awareness especially amongst the clinicians regarding TRALI is needed for prevention and treatment of this potentially severe complication of blood/component transfusion.

Transfusion-related acute lung injury: from bedside to bench and back

Over the past 60 years, the transfusion medicine community has attained significant knowledge regarding transfusion-related acute lung injury (TRALI) through the bedside to bench and back to the bedside model. First, at the bedside, TRALI causes hypoxia and noncardiogenic pulmonary edema, typically within 6 hours of transfusion. Second, bedside studies showed a higher incidence in plasma and platelet products than in red blood cell products (the fatal TRALI incidence for plasma is 1:2-300 000 products; platelet, 1:3-400 000; red blood cells, 1:25 002 000), as well as an association with donor leukocyte antibodies (∼ 80% of cases). Third, at the bench, antibody-dependent and antibody-independent mechanisms have been described, requiring neutrophil and pulmonary endothelial cell activation. Antibodies, as well as alternate substances in blood products, result in neutrophil activation, which, in a susceptible patient, result in TRALI (2-hit hypothesis). Fourth, back to the bedside, policy changes based on results of these studies, such as minimizing use of plasma and platelet products from donors with leukocyte antibodies, have decreased the incidence of TRALI. Thus, steps to mitigate TRALI are in place, but a complete mechanistic understanding of the pathogenesis of TRALI and of which patients are at highest risk remains to be elucidated.

A national survey of transfusion-related acute lung injury risk reduction policies for platelets and plasma in the United States

BACKGROUND

Little information exists on the specific transfusion-related acute lung injury (TRALI) risk reduction practices used by multiple blood collecting institutions in the United States.

STUDY DESIGN AND METHODS

An AABB-appointed TRALI working group designed a set of questions about TRALI risk reduction for platelets (PLTs) and plasma. AABB member institutions were asked to respond via an Internet-based survey during a 3-week period in August through September 2009.

RESULTS

Valid responses were received from 47 US blood centers (accounting for 1.57 million apheresis PLT units and 3.15 million whole blood-derived transfusable plasma units) and 56 hospital blood collectors. Among the blood centers, 87 and 98% had initiated some PLT and plasma risk reduction, respectively. HLA antibody testing of plateletpheresis donors was performed by 20 (43%) blood centers. There was substantial variation in the number of pregnancies (from one to more than four) that triggered testing and most centers did not screen based on a transfusion history. Almost all centers had policies to redirect HLA antibody-positive donors to whole blood donation and to potentially retest HLA antibody-negative donors. There were no blood centers performing HNA antibody testing. Sex-based risk reduction policies for plasma included all male, or predominantly male, and never-pregnant females; these varied by blood center, blood group, and method of plasma collection. A majority of centers indicated increased production of plasma frozen within 24 hours after phlebotomy.

CONCLUSIONS

Almost 3 years after the publication of the initial AABB bulletin on this issue, TRALI risk reduction strategies are commonly employed at most US blood centers. However, procedures are not uniform.

Blood still kills: six strategies to further reduce allogeneic blood transfusion-related mortality

After reviewing the relative frequency of the causes of allogeneic blood transfusion-related mortality in the United States today, we present 6 possible strategies for further reducing such transfusion-related mortality. These are (1) avoidance of unnecessary transfusions through the use of evidence-based transfusion guidelines, to reduce potentially fatal (infectious as well as noninfectious) transfusion complications; (2) reduction in the risk of transfusion-related acute lung injury in recipients of platelet transfusions through the use of single-donor platelets collected from male donors, or female donors without a history of pregnancy or who have been shown not to have white blood cell (WBC) antibodies; (3) prevention of hemolytic transfusion reactions through the augmentation of patient identification procedures by the addition of information technologies, as well as through the prevention of additional red blood cell alloantibody formation in patients who are likely to need multiple transfusions in the future; (4) avoidance of pooled blood products (such as pooled whole blood-derived platelets) to reduce the risk of transmission of emerging transfusion-transmitted infections (TTIs) and the residual risk from known TTIs (especially transfusion-associated sepsis [TAS]); (5) WBC reduction of cellular blood components administered in cardiac surgery to prevent the poorly understood increased mortality seen in cardiac surgery patients in association with the receipt of non-WBC-reduced (compared with WBC-reduced) transfusion; and (6) pathogen reduction of platelet and plasma components to prevent the transfusion transmission of most emerging, potentially fatal TTIs and the residual risk of known TTIs (especially TAS).