Assessment of Safety and Efficacy of Expanded Hemodialysis with Medium Cut-Off Dialyzer Compared to Haemodiafiltration

Background: Removal of large uraemic toxins is still a challenge. Haemodiafiltration (HDF) has produced some results, although large convective volume, optimal vascular access to increase the blood flow rate and strict water quality management are required. Medium cut-off, high-retention-onset membranes have been recently developed, introducing the concept therapy called expanded haemodialysis (HDx). Furthermore, vitamin E-coated membrane has potential beneficial effects on inflammation and oxidative stress. Methods: A prospective longitudinal multicentre study was conducted for 3 months among 24 chronic haemodialysis patients. Patients were randomly assigned into either HDF with high-flux membrane or HDx with Theranova or ViE-X membrane. The primary goal was to assess albumin loss among the three types of dialyzers. Secondary goals included assessment of depurative efficacy for uraemic toxins and clinical outcomes. Results: Mean albumin loss was significantly higher in patients undergoing HDx with Theranova membrane, without any difference in serum albumin concentration among the three groups. Instantaneous clearance of small and middle molecules was significantly higher in patients undergoing HDF, but we did not find differences in removal ratio and Kt/V. Reduction in the erythropoietin resistance index was observed in patients treated with ViE-X membrane due to their lower dialysis vintage. Conclusions: The higher albumin loss during HDx has no effects on pre-dialysis serum albumin. HDx with Theranova in the presence of lower session length, lower Qb, lower convective dose, and lower instantaneous clearance reached the same dialysis efficacy compared to HDF.