Effect of the Leukostop filter on pulmonary function following blood transfusion in patients with thalassemia major

This study evaluated the effect of the Leukostop filter, a device which reduces the number of leukocytes in blood, on pulmonary function in 15 patients with thalassemia major. Spirometry and oxygen saturation were used to evaluate the influence of filtering the blood. The transfusions consisted of blood which had or had not passed through a Leukostop filter. Blood transfusion induced a significant drop in FEV(1)/FVC ratio in 4 patients, an effect which disappeared following use of the Leukostop filter. Oxygen saturation improved after 6 months of using the Leukostop filter and improved acutely following blood transfusion (both with and without the filter). We conclude that removing most of the leukocytes from the blood during transfusions prevents bronchoconstriction and improves oxygen saturation.