Leukoreduction in the setting of open heart surgery: a prospective cohort-controlled study

BACKGROUND: Proven clinical benefits of leukoreduced blood components include reduced febrile nonhemolytic transfusion reactions, alloimmunization against HLA antigens, and CMV transmission. Immunomodulatory effects of leukoreduction have also been postulated to play a significant role in the clinical outcome of open heart surgery. STUDY DESIGN AND METHODS: A prospective case control study was implemented in which all patients admitted over a 1-year period for open heart surgery at a single hospital were given leukoreduced blood products. Clinical outcomes were prospectively measured and compared to a historical cohort of patients from the previous year when leukoreduced blood products were not routinely used. RESULTS: A significant improvement in the mean postoperative length of stay was seen in the study group (N = 645) versus control group (N = 501; 10.1 vs. 9.5 days; p = 0.005). No significant changes were seen in the rate of mediastinitis, operative mortality, or stay in the intensive care unit. There was no difference in the postoperative length of stay among study patients who did not receive transfusion (N = 308) versus control patients who did not receive transfusion (N = 296; 6.2 vs. 6.4 days; p = 0.104). CONCLUSIONS: The use of leukoreduced blood was associated with a decrease in the postoperative length of stay in the setting of open heart surgery. The mechanisms through which these changes in clinical outcomes are generated remain unknown.