title: Technical evaluation of dialysate flow in a newly designed dialyzer.
abstract: Rexeed was developed by Asahi Kasei Medical using wave-shaped hollow fibers, a full baffle, and a short taper housing to improve dialysate flow. The present study is clarifies improvement in dialysate flow with Rexeed-15 compared with that of a conventional dialyzer. Dialysate flow was evaluated by the pulse-response method. Dialysate pressure and tracer concentration were measured at a blood-side flow rate (QBeta) of 200 ml/min, a dialysate-side flow rate (QD) of 500 ml/min, and a net filtration rate (QF) of 0 ml/min using needles placed in the test dialyzer. Dialyzer performance was evaluated by measuring urea and vitamin B12 clearance at QB = 200 and 400 ml/min, QD = 300-800 ml/min, and QF = 0 ml/min. In the conventional dialyzer, dialysate channeling was observed. In contrast, Rexeed-15 had a uniform dialysate flow. Urea and vitamin B12 clearance with Rexeed-15 was slightly sensitive to QD. The overall mass transfer coefficient for urea with Rexeed-15 was more than 50% higher than that of the conventional dialyzer, indicating the possibility of reduced dialysate usage with Rexeed. Rexeed has a highly optimal dialysate flow, due to the wave-shaped hollow fibers and the new housing, and gives increased clearance for lower-molecular-weight substances.
authors.affiliation: Department of Chemical Engineering, 21COE Center for Practical Nano-Chemistry, Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, Tokyo, Japan.
authors.forename: Ken-Ichiro
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Matsukawa
authors.forename: Taiji
authors.initials: T
authors.lastname: Yakushiji
authors.forename: Makoto
authors.initials: M
authors.lastname: Fukuda
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Hiyoshi
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Sakai
mesh_terms: D004867:Equipment Design; D011312:Pressure; D006435:Renal Dialysis / Q000295:instrumentation* / Q000379:methods; D012212:Rheology; D014508:Urea / Q000097:blood; D014805:Vitamin B 12 / Q000097:blood
chemical_list: D014508:Urea; D014805:Vitamin B 12