MO646: Effect of a High-Flux Dialyzer Applied to HFR Supra on the Removal of Large Uraemic Toxins in Haemodialysis Patients: Results from a Randomized Controlled Study

Abstract

Abstract BACKGROUND AND AIMS HFR-Supra (haemodiafiltration with the regeneration of the ultrafiltrate) is a highly biocompatible dialysis technique characterized by an adsorptive resin cartridge with high protein-bound toxin adsorption capacity without removal of albumin, mimicking both glomerular and tubular functions. However, the low-flux dialyzer contained in the second diffusive stage of the HFR Supra system may hamper the removal of large uraemic toxins. This study assessed the large uraemic toxin removal ability of a new HFR system (HFR-H) which combines adsorption such as in HFR-Supra, with a high-efficiency high-flux haemodialysis membrane. METHOD In an open, randomized, cross-over, single-center, controlled study, 16 adult chronic haemodialysis patients were treated by haemodiafiltration with the regeneration of the ultrafiltrate with the HFR-Supra or the HFR-H system. All other dialysis parameters were kept constant in both study arms. All the treatments were delivered with Flexya dialysis monitor (Medtronic) in the middle-week session, lasting 4-h. The reduction rate (RR) of urea, creatinine, phosphate, β2-microglobulin, kappa (κFLC) and lambda (λFLC) free light chains and albumin, was intra-individually compared for the two dialysis types with linear mixed models. RESULTS The RRs for β2-microglobulin, κFLC and λFLC were significantly higher with the HFR-H system than those obtained with HFR-Supra (Figure). There were no significant differences in the RR for urea, creatinine, phosphate, interleukin-6 and albumin. CONCLUSION This study demonstrates that treating patients with an HFR-H instead of an HFR-Supra system significantly increases the elimination of middle and large molecules.