Biomedical subjects
Publications and source records attributed to Y Ozaku.
Orally diluting hemofiltration (ODHF), herein reported, is a new technique where the body fluid is purified by cooperative procedures of dilution-supplementation with oral electrolyte solution and filtration using the RP-6 dialyzer. One uremic patient was maintained for two months on a five-hour, three-times-per-week ODHF schedule, and another patient was maintained for four months on the same regimen with no supportive hemodialysis.
Introduction of high flux-type dialyzers, such as the RP-6, makes it necessary to devise an ultrafiltration rate controller for a single pass system. For this purpose, a new pre-set ultrafiltration rate controller has been developed and examined experimentally and clinically. The controller has twin chambers, each of which is divided into two symmetrical parts by a vertically-placed diaphragm. The diaphragm shifts repeatedly from right to left, aspirating in and driving out fresh or used dialysate alternately. If one removes a certain amount of used dialysate from a branch of the efferent line, negative pressure develops and aspirates an equal amount of water from the dialyzer. Therefore, extra dialysate obtained by a pump precisely reflects ultrafiltration rate. The controller has been used on five patients. The scheduled ultrafiltration rate was easily obtainable. The apparatus is also available for hemodiafiltration. Initial clinical trial has been promising.
Three times 3 hr/wk hemodiafiltration (simultaneous hemofiltration and dialysis: HDF) using Toray HDF system has been carried out on 4 patients. Filters used were Toray Filtryzers (membrane: polymethylmethacrylate, surface area 1.15 M2) with a dialysate flow of 500 ml/min. Nine to 10 L of body fluid was removed and 7-8 L of substitution fluid was reinfused distal to the filter (postdilution). Short-time HDF was favorable accepted by the patients. Blood pressure was stable, and disequilibrium syndrome negligible. Clinical courses as well as laboratory findings of the patients were satisfactory. The reduction rate of middle to larger molecules was 20 to 100% higher compared to conventional HD as measured by chromatogram. Loss of amino acids was about 3 gm/treatment. Reduction of hormones was negligible and no depletion syndrome was observed throughout the observation period up to 10 mos. Acidosis was corrected within 3-4 hrs. Elevated blood concentration of lactate and acetate gradually decreased to a pretreatment level within 2-3 hrs after termination of the procedure. Removal of middle molecules by HDF, in addition to removal of small molecules by conventional hemodialysis, is considered to be the treatment of choice for uremic patients.