Leukocyte depletion results in improved lung function and reduced inflammatory response after cardiac surgery

Leukocyte depletion during cardiopulmonary bypass has been demonstrated in animal experiments to improve pulmonary function, Conflicting results have been reported, however, with clinical depletion by arterial line filter of leukocytes at the beginning of cardiopulmonary bypass. In this study, we examined whether leukocyte depletion from the residual heart-lung machine blood at the end of cardiopulmonary bypass would improve lung function and reduce the postoperative inflammatory response. Thirty patients undergoing elective heart operations were randomly allocated to a leukocyte-depletion group or a control group. In the leukocyte-depletion group (n = 20), all residual blood (1.2 to 2.1 L) was filtered by leukocyte-removal filters and reinfused after cardiopulmonary bypass, whereas in the control group an identical amount of residual blood after cardiopulmonary bypass was reinfused without filtration (n = 10). Leukocyte depletion removed more than 97% of leukocytes from the retransfused blood (p