Effects of hemoadsorption on cytokine removal and short-term survival in septic rats

Objective: A broad-spectrum immune-regulating therapy could be beneficial in the treatment of sepsis. Our previous studies have shown that a hemoadsorption device (CytoSorb) removes both pro- and anti-inflammatory cytokines and improves survival in experimental endotoxemia. We sought to determine whether hemoadsorption can also be effective in the treatment of sepsis. Design: Randomized controlled laboratory experiment. Setting: University laboratory. Interventions: Rats were subjected to cecal ligation and puncture (CLP) and 20 hrs later were randomized to receive either hemoadsorption or sham treatment using an arterial-venous circuit. Hemoadsorption was accomplished using a cartridge containing Cytosorb beads. Blood was drawn for cytokine measurements and mean arterial pressure (MAP) was continuously monitored. Cytokines were measured via multiplex bead immunoassays. Survival time was observed for 9 hours after the intervention and assessed by Kaplan-Meier statistics. The overall survival in each group was compared using Fisher's exact test. Finally, we used a Cox proportional-hazards model to examine the effects of cytokine removal on survival time. Measurements and Main Results: Baseline plasma cytokine concentrations and MAP were similar between hemoadsorption and sham-treated groups. However, the concentrations of tumor necrosis factor, interleukin (IL)-1 beta, IL-6, and IL-10 were significantly lower after hemoadsorption compared to the sham group. Six hours after treatment ended, IL-6 and IL-10 concentrations were still lower in hemoadsorption group. MAP was significantly better in hemoadsorption compared to sham-treated animals (p < .05). Finally, mean survival time was significantly longer (720 vs. 381 min, p < .05, Mann-Whitney test), and overall survival was significantly better (11/17 vs. 2/16, p < .01) with hemoadsorption compared to sham. Combined reduction in both IL-6 and IL-10 was associated with a significantly decreased risk of death (hazard ratio, .11, p = .005). Conclusion: Hemoadsorption reduced circulating cytokines, improved MAP, and resulted in better short-term survival in CLP-induced septic rats.