Effects of allogeneic leukocytes in blood transfusions during cardiac surgery on inflammatory mediators and postoperative complications.

OBJECTIVE To investigate whether the higher prevalence of postoperative complications in cardiac surgery after transfusion of leukocyte-containing red blood cells can be related to inflammatory mediators. DESIGN Analysis of inflammatory markers interleukin-6, interleukin-10, interleukin-12, and procalcitonin in patients participating in a randomized trial comparing leukocyte-depleted with leukocyte-containing, buffy-coat-depleted red blood cells. SETTING Two university-affiliated hospitals in the Netherlands. SUBJECTS A total of 346 patients undergoing cardiac valve surgery with a complete series of pre- and postoperative blood samples. MEASUREMENTS AND MAIN RESULTS There were no differences in the cytokines and procalcitonin concentrations between both study arms when the patients arrived in the intensive care unit. In subgroups, patients who received zero to three red blood cell transfusions showed similar cytokine concentrations in both study arms, whereas patients with > or = 4 red blood cell transfusions had significantly higher interleukin-6 concentrations in the leukocyte-containing, buffy-coat-depleted red blood cell group. Patients who developed postoperative infections and multiple organ dysfunction syndrome showed, respectively, increased concentrations of interleukin-6 and interleukin-12 in the leukocyte-containing, buffy-coat-depleted, red blood cell group. The interaction tests in these subgroups showed significantly different reaction patterns in the leukocyte-containing, buffy-coat-depleted red blood cell group compared with leukocyte-depleted red blood cell group for interleukin-6 and interleukin-12. Multivariate analysis showed a high interleukin-6 concentration with multiple organ dysfunction syndrome and both high interleukin-6 and interleukin-10 concentrations with hospital mortality. CONCLUSIONS Allogeneic leukocyte-containing blood transfusions compared with leukocyte-depleted blood transfusions induce dose-dependent significantly higher concentrations of proinflammatory mediators in the immediate postoperative period after cardiac surgery. High concentrations of interleukin-6 are strong predictors for development of multiple organ dysfunction syndrome, whereas both interleukin-6 and interleukin-10 are associated with hospital mortality. These findings suggest that leukocyte-containing red blood cells interfere with the balance between postoperative proinflammatory response, which may further affect the development of complications after cardiac surgery.