Do peritoneal catheters remove pro-inflammatory cytokines after cardiopulmonary bypass in neonates?

Background. Cardiopulmonary bypass (CPB) in neonates induces a cytokine-mediated capillary leak syndrome that can cause organ dysfunction. Removing harmful cytokines after CPB may attenuate this response. This study measured the concentrations of serum and peritoneal fluid (PF) cytokines after CPB to determine if harmful cytokines can be removed with peritoneal catheters. Methods. Neonates (n = 18) had cardiac surgery using CPB with circulatory arrest. Peritoneal catheters were placed at the end of surgery to drain excess fluid. Serum samples were obtained before and after CPB, and PF after CPB. Cytokines were measured by enzyme-linked immunosorbent assay. Results. Tumor necrosis factor-α and interleukin-1β (IL-1β) were not detected in any serum or PF sample. Serum concentrations of IL-6, IL-8, and IL-10 increased significantly after CPB. PF concentrations of IL-6 and IL-8 exceeded serum concentrations, whereas IL-10 concentrations were higher in the serum. There was a significant negative correlation between serum and PF concentrations of IL-6 after CPB (r = −0.63; p< 0.05). Conclusions. PF has very high concentrations of the proinflammatory cytokines, IL-6 and IL-8, after CPB but not the antiinflammatory cytokine IL-10. The PF may be a depot for the harmful inflammatory cytokines after CPB, and removing the PF could lower serum concentrations.