Maintaining low concentrations of plasma  2-microglobulin through continuous slow haemofiltration

Abstract

As a first step in the development of a future wearable artificial kidney, we conducted three forms of treatment with continuous haemofiltration (CHF) on a group of 10 patients in an attempt to determine what plasma values of small molecules and beta 2-microglobulin (beta 2-M) could be maintained. In the first system, one ordinary 4-h haemodialysis, followed by 7-day CHF with 51 exchange per day, was repeated. The second system consisted of CHF with 51 exchange/day and thrice weekly slow nocturnal dialysis. The third system used CHF with 101 exchange per day. The first, second and third systems were used with three, four and four patients, respectively, for at least 4 weeks each. PAN-DX and FH-66 haemofilters were used eight and three times, respectively, with continuous infusion of heparin at 500-700 units/h. In the first system, the pre-CHF plasma beta 2-M was 45.5 +/- 3.1 mg/l, against a much lower 18.8 +/- 1.0 mg/l 4 weeks later. With the second system, this decrease was from 43.5 +/- 5.7 mg/l to 18.1 +/- 1.1 mg/l with 4 weeks treatment, and from 44.7 +/- 3.4 mg/l to 18.1 +/- 1.4 mg/l with 3 weeks treatment. Pre-haemodialysis treatment levels of urea nitrogen, plasma creatinine and uric acid in the first system were greater than ordinary pre-haemodialysis levels. On the second system, these were kept at -54 +/- 8.3%, -52.2 +/- 6.7% and -47.6 +/- 4.4% of the ordinary pre-haemodialysis levels, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Present Status and Perspective of the Development of a Bioartificial Kidney for Chronic Renal Failure Patients

“…A continuous hemofilter should maintain function for at least one week, and an artificial membrane and tubular epithelial cell‐layers should maintain tubular function for one month, if possible. We previously confirmed that 10 L/day of continuous hemofiltration enabled patients to maintain their time‐averaged concentrations of urea, creatinine, uric acid, inorganic phosphate and β 2 ‐microglobulin at lower levels than those of the patients treated with standard hemodialysis (16). Thus, as the first step towards the development of bioartificial kidneys, we intended to develop a bioartificial kidney system by which 10 L/day of filtrate could be obtained from a patient using a continuous hemofilter and 6/10 L of filtrate would be regenerated and metabolized, discarding 4 L/day by replaced by drinking and meals.…”

Evaluation of Water and Electrolyte Transport of Tubular Epithelial Cells Under Osmotic and Hydraulic Pressure for Development of Bioartificial Tubules

“…They also used a 0.4 m 2 membrane surface area of bioartificial tubules on a dog with acute renal failure as long as 3 days (9). We previously reported that continuous slow hemofiltration therapy with a 10 L exchange per day provided low serum BUN and creatinine levels (10). In this therapy, regeneration of filtrated fluid or supply of substitution fluid was needed.…”

Development of bioartificial kidneys

“…[6][7][8][9] Continuous haemofiltration with 10 L (L)/day of ultrafiltrate in eight maintenance dialysis patients was evaluated for four or eight weeks by Saito et al . 10 Plasma urea nitrogen, creatinine, and uric acid levels in those patients remained at negative 60 to negative 40% of the ordinary predialysis values ( Fig. 1), plasma inorganic phosphate levels were maintained within normal limits three weeks after the start of continuous treatment, and the plasma b 2 -microglobulin level remained under 20 mg/L 4 weeks after the start of continuous treatment (Fig.…”

“…Although continuous haemofiltration was previously favoured for chronic dialysis patients, it had been tried only for short durations because of the limited antithrombogenic capability of continuous haemofilters 6–9 . Continuous haemofiltration with 10 L (L)/day of ultrafiltrate in eight maintenance dialysis patients was evaluated for four or eight weeks by Saito et al 10 . Plasma urea nitrogen, creatinine, and uric acid levels in those patients remained at negative 60 to negative 40% of the ordinary predialysis values (Fig.…”