Development of a cold dialysate regeneration system for home hemodialysis.

Background/aims: Because longer and/or more frequent dialysis has potential clinical benefits, home hemodialysis (HHD) systems should provide flexible renal replacement therapies. We propose a new cold dialysate regeneration system that requires 10 l per treatment for HHD.

Methods: We designed a dialysate regeneration system using cold dialysate and 2 activated carbon columns alternatively switched between adsorption and desorption. Urea adsorption ratios were compared in three different conditions; cold dialysate (5.7 degrees C), normal dialysate (36.8 degrees C), and cold dialysate with washing. In vivo tests (n = 8) were conducted to validate this system.

Results: The urea removal ratios were 20.0 +/- 1.7% in cold dialysate, 36.0 +/- 1.7% in normal dialysate, and 82.5 +/- 1.2% in cold dialysate with washing. In animal experiments, the urea reduction ratio was 60.9 +/- 6.3%, Kt/V was 1.0 +/- 0.2, and serum electrolytes remained stable.

Conclusion: The proposed cold dialysate regeneration system using a small volume of dialysate will be useful for HHD.