The effect of RBC transfusions on cytokine gene expression after cardiac surgery in patients developing post-operative multiple organ failure
To determine the effect of red blood cell (RBC) transfusions during cardiac surgery on cytokine gene expression (GE) in relation to multiple organ failure (MOF) development after systemic inflammatory response syndrome (SIRS). RBC transfusion in cardiac surgery patients is dose-dependently associated with post-operative MOF, possibly acting as a second hit after cardiopulmonary bypass. For this observational study, 29 patients divided into four groups of cardiac surgery patients were selected from a randomised controlled trial (RCT). Group 1: no-RBC, no-MOF (N = 8); group 2: MOF, no-RBC (N = 7); group 3: RBC, no-MOF (N = 6); group 4: RBC and MOF (N = 8). Selection was based on age, gender, number of (leukocyte-depleted) RBC transfusions, type and duration of surgery. A 114 cytokine GE array was applied to blood samples withdrawn before and 24 h after surgery. Expression of selected genes was confirmed with reverse transcriptase real time-polymerase chain reaction (RT-PCR). Nineteen of the 39 detectable genes showed a significant change in GE after surgery. Confirmed by RT-PCR, transfused MOF patients exhibit significantly less downregulation of CD40 ligand than control patients. Patients who would develop MOF show significantly larger increases in GE of transforming growth factor-α (TGF-α), tumour necrosis factor (TNF)-superfamily members 10 and 13B (TNFsf10/13B). When tested at 24 h after surgery, cytokine GE in peripheral blood leucocytes showed no significant differences between those transfused and those not transfused. Some alterations were seen in those developing MOF compared to those who did not, but the findings offer no role of leukocyte depleted (LD) RBC transfusion in the development of MOF.