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Abstract: FR-PO458

High-Volume Postdilution Online Hemodiafiltration Is Possible Even at Low Blood Flow Rates

Session Information

Category: Dialysis

  • 701 Dialysis: Hemodialysis and Frequent Dialysis


  • Jo, Young-Il, Konkuk University Medical Center, Seoul, Korea (the Republic of)
  • Kim, Ki sung, Konkuk University Medical Center, Seoul, Korea (the Republic of)
  • Chung, Kyung-Hee, Konkuk University Medical Center, Seoul, Korea (the Republic of)
  • Seo, Mi-Jung, Konkuk University Medical Center, Seoul, Korea (the Republic of)

Recent evidence suggests that high-volume hemodiafiltration (HDF) improves patient survival. However, in patients with low blood flow rate (BFR), it is not easy to obtain a high convection volume (CV) with postdilution online HDF. The aim of this study was to investigate whether it is possible to achieve high CV, defined as ≥22 L/session, with postdilution HDF even for patients with low BFR.


A total of 33 consecutive patients undergoing thrice-weekly postdilution HDF were included. In order to obtain a high CV, we optimized treatment parameters such as treatment time (TT), BFR, needle size and filtration fraction (FF) in all patients according to a stepwise protocol, depending on patent’s condition. All dialysis machines were equipped with auto-substitution system. Data of 2592 sessions for one month before and after completion of optimization of treatment parameters were analyzed. The mean CV was determined.


The mean age of patients was 62.5±12.5 years, and 45.5% male. Before the initiation of a stepwise protocol, TT was 233.6±10.9 min, BFR was 267.1±11.1 mL/min, and 84.8% of needles were 16G and 15.2% were 15G. The mean CV was 23.8±2.4 L/session and 75.8% of patients reached CV of ≥22 L/session. After completion of optimization, 90.9% of patients reached a high CV with mean of 24.4±2.3 L/session. Of note, TT was 241.8±16.1 min, BFR was 293.6±12.5 mL/min, and 69.7% of needles were 16G and 30.3% were 15G. Interestingly, in 96.70% of patients who reached a high CV, BFR was less than 300 mL/min with mean of 293.5±12.5 mL/min. In addition, 90.0% of patients with BFR of less than 300 mL/min reached a high CV. The changes of CV after optimization of parameters is shown in the figure.


The high convection volumes could be achieved by increasing of BFR and treatment time and optimization of FF even if high BFR was not obtained. High-volume postdilution HDF is possible in routine clinical practice even for patients with low BFR less than 300 mL/min.