Transitioning from Frequent High-Flux Hemodialysis to Frequent Online Hemodiafiltration: Successive Paradigm Shifts towards Optimal Dialysis Therapy

Background: Frequent highflux hemodialysis (fHD) has improved outcomes compared to conventional thrice-weekly schedule (cHD). Likewise, thrice-weekly high-volume online hemodiafiltration has shown benefits compared to cHD. We previously established the feasibility, safety, and potential advantages of fHDF over fHD and transitioned our long-term in-center dialysis program from short daily highflux hemodialysis (SDHD) to short daily high-volume online hemodiafiltration (SDHDF). This study aims to delineate the transition process of implementing fHDF as the standard therapy in our in-center dialysis program. Methods: We documented patient demographics including number, age, dialysis vintage, presence of diabetes, vascular access type and kidney transplantation (KTx) waitlist. The fHDF parameters encompassed 6 x 2-hour sessions/week, 350 ml/min blood flow and 500 ml/min dialysate flow. Equipment included the Aquaboss Osmosis System, BBraun Diálog+HDF and IQ-HDF Machines with Xevonta Hi23 single-use dialyzer. Anticoagulation adjustments, HDF modalities and substitution volume goals were assessed. We also analyzed this transtion's cost implications for providers and payors. Results: In November 2023, seventy patients were switched from SDHD to SDHDF, 40Males/30Females, age 63.2±15.2 years (29-91), dialysis vintage 53.5±55.1 months (3-227), 38% diabetes, 53% AVF, 38% PermCath, 9% Graft, 44% waitlisted for KTx, 90% post-dilution HDF and 10% pre-dilution HDF due to limited blood flow rate, substitution volume aimed for post-dilution HDF: 12.5 L/2h-session (75 L/week) or pre-dilution HDF: 25 L/2h-session (150 L/week). There was a 23% mean increase in heparin doses. Cost of consumables increased about 21%, while mean reimbursement by payors increased 35.3%. In Brazil, each new HDF machine costs 4,000.00-7,500.00 US dollars more than a new HD machine. Conclusion: The transition from in-center fHD to fHDF represents a second paradigm shift in our dialysis program (cHD to fHD was the first, in 2006). Whilst requiring comprehensive evaluation of patient demographics, treatment parameters, equipment considerations and cost implications, this successfully managed modality switch yields potential clinical benefits towards optimizing modern dialysis care.