Leukocyte filtration in cardiac surgery: a review

Leukocyte filtration has evolved as an important technique in cardiac surgery with cardiopulmonary bypass to prevent pathogenic effector functions mediated by activated leukocytes. The underlying mechanisms that result in an improvement of laboratory variables as well as clinical outcome are not resolved yet. Moreover, the optimum strategy for the use of current filtration technology has not been systematically evaluated. This paper, therefore, reviews how activated leukocytes may lead to tissue damage, summarizes the known effects of leukocyte filtration on clinical outcome and laboratory parameters, and deals with current experimental and clinical efforts to further limit the pathogenic effects of leukocytes in cardiac surgery.