Effects of Medium Cutoff Membranes on Pro-Inflammatory Cytokine and Oxidative Marker Levels in Patients with Sepsis Who Developed Acute Kidney Injury.

INTRODUCTION: There is insufficient data on the role of the medium cutoff (MCO) membranes in the clearance of pro-inflammatory cytokines and oxidant radicals in patients with sepsis requiring hemodialysis. METHODS: The study consisted of 38 septic patients who developed acute kidney injury (AKI) and who were scheduled to undergo 2 sessions of hemodialysis. Nineteen patients underwent their first dialysis session with the MCO membrane and 19 patients with the high-flux (HF) membrane. In the second session, the membranes were switched. Pro-inflammatory cytokine and oxidative marker levels were measured in blood samples obtained before and after both dialysis sessions. Reduction ratios were compared for the 2 types of hemodialysis membranes. RESULTS: After the first session, there was a greater reduction in tumor necrosis factor (TNF)-α with the MCO membrane (28.2 ± 21.1 vs. 8.0 ± 6.6, p = 0.001). After the second session, there was a greater reduction in interleukin (IL)-6 (27.8 ± 26.5 vs. 5.9 ± 13.3, p = 0.003) and IL-1ß (20.5 ± 21.1 vs. 4.0 ± 6.5, p = 0.004) with the MCO membrane. When the first and second sessions of all 38 patients were compared, the reductions in TNF-α, IL-6, and IL-1ß were consistently greater for MCO than HF (p = 0.001, p = 0.006, p < 0.001, respectively). The reductions in total antioxidant status, total oxidant status, and myeloperoxidase were not statistically different for the 2 types of dialysis membranes. CONCLUSIONS: MCO membrane was superior to HF membrane in the removal of cytokines in septic patients with AKI. However, a similar effect was not observed for oxidative stress markers.