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Published on: February 13, 2016
Internal filtration in dialyzers with different membrane permeabilities
Yuichi Sato1, Kenjiro Kimura, Tatsuya Chikaraishi
1Department of Urology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, 216-8511, Japan. sato@marianna-u.ac.jp
Summary
Enhanced internal filtration (IF) in hemodialysis is linked to dialyzer membrane permeability. Higher permeability leads to increased IF, but also causes significant membrane fouling during dialysis.
Area of Science:
- Nephrology
- Biomedical Engineering
- Renal Replacement Therapy
Background:
- Hemodialysis with enhanced internal filtration (IF) is an emerging alternative to conventional dialysis.
- Dialyzer geometry and membrane permeability are key factors influencing IF.
- Directly measuring IF and its relationship with membrane permeability has been challenging.
Purpose of the Study:
- To directly measure internal filtration (IF) and membrane permeability in hemodialyzers.
- To investigate the association between IF and hollow-fiber dialyzer membrane permeability.
- To assess the impact of IF on membrane fouling over time.
Main Methods:
- An experimental tandem-dialyzer circuit was designed to measure IF.
- Blood concentration changes between serially connected dialyzers quantified IF.
- Membrane permeability was measured before and after four hours of circulation.
Main Results:
- Significant IF was observed, ranging from 23.5 to 100 ml/min.
- IF increased linearly with increasing membrane permeability.
- Membrane permeability decreased more in the first dialyzer, indicating substantial fouling.
Conclusions:
- Membrane permeability is a critical determinant of internal filtration in hemodialysis.
- Enhanced internal filtration, while potentially beneficial, can lead to significant membrane fouling.
- The developed method allows for direct measurement of IF and assessment of membrane fouling.
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