Microaggregate blood filtration and the febrile transfusion reaction

Abstract

Patients (74) with chronic transfusion requirements and histories of repetitive febrile reactions were transfused with 1138 U of microaggregate-filtered red cells. The filtered blood was prepared using either a direct interception or a depth filter. One half of the units were centrifuged immediately prior to filtration. Microaggregate filtration reduced the overall incidence of febrile transfusion reactions by 77%. The centrifugation-filtration protocol reduced the rate of reactions by 98%. There were no differences between the ability of the different filters to reduce the reaction rate; red cell loss was twice as large with the depth filter as with the direct interception filter. The numerical criterion for leukocyte-poor blood was met in all units processed by centrifugation-filtration. Only units processed during the last 2 wk of shelf-life fulfilled this criterion when centrifugation was omitted from the procedure. The majority of the latter units were clinically tolerated well due to their reduced granulocyte content.