Double-blind, randomized controlled trial on the effect of leukocyte-depleted erythrocyte transfusions in cardiac valve surgery

Background - Leukocytes in allogeneic blood transfusions are believed to be the cause of immunomodulatory events. A few trials on leukocyte removal from transfusions in cardiac surgery have been conducted, and they showed inconclusive results. We found in a previous study a decrease in mortality rates and number of infections in a subgroup of more heavily transfused patients. Methods and Results - Patients (n = 496) undergoing valve surgery ( with or without CABG) were randomly assigned in a double-blind fashion to receive standard buffy coat - depleted ( PC) or prestorage, by filtration, leukocyte-depleted erythrocytes (LD). The primary end point was mortality at 90 days, and secondary end points were in-hospital mortality, multiple organ dysfunction syndrome, infections, intensive care unit stay, and hospital stay. The difference in mortality at 90 days was not significant (PC 12.7% versus LD 8.4%; odds ratio [OR], 1.52; 95% confidence interval [CI], 0.84 to 2.73). The in-hospital mortality rate was almost twice as high in the PC group (10.1% versus 5.5% in the LD group; OR, 1.99; 95% CI, 0.99 to 4.00). The incidence of multiple organ dysfunction syndrome in both groups was similar, although more patients with multiple organ dysfunction syndrome died in the PC group. LD was associated with a significantly reduced infection rate ( PC 31.6% versus LD 21.6%; OR, 1.64; 95% CI, 1.08 to 2.49). In both groups, intensive care unit stay and hospital stay were similar, and postoperative complications increased with the number of transfused units. Conclusions - Mortality at 90 days was not significantly different; however, a beneficial effect of LD in valve surgery was found for the secondary end points of in-hospital mortality and infections.