The effect of ultra-low sodium dialysate in CAPD. A kinetic and clinical analysis

M. Nakayama, K. Yokoyama, H. Kubo, H. Matsumoto, T. Hasegawa, T. Shigematsu, Y. Kawaguchi, O. Sakai

Research output: Contribution to journalArticlepeer-review

45 Citations (Scopus)


In peritoneal dialysis, sodium (Na) passes through the peritoneal membrane to a lesser extent than H 2O and thus hypotonic fluid is removed indicating that Na removal is inefficient. Therefore we developed an ultra-low Na dialysate (ULNaD) [Na 98 mmol/liter, osmolality 340 mOsm/kg, glucose (G), 2.48%] to facilitate trans-peritoneal Na removal. The aim of the study was to examine (a) the fluid and Na kinetics of this solution, and (b) the clinical effect in the over-hydrated patient. Regarding the former, in six cases, changes in the effluent Na levels during a 240-minute dwell of ULNaD were measured at 60-minute intervals. In eighteen cases, the transperitoneal net-Na removal (Na removal) and drained ultrafiltration (UF) volume after a 240-minute dwell of ULNaD were measured and compared to two types of standard Na dialysate (SNaD) [Na 132 mmol/liter, 1.36% G (348 mOsm/kg) and 2.27% G (396 mOsm/kg)]. The effluent Na levels increased gradually until the end of the dwelling. Drained UF volume of ULNaD (224 ± 25 ml) was more than 1.36% G SNaD (77 ± 33 ml, p < 0.01), but it was less than 2.27% G SNaD (341 ± 32 ml, p < 0.01). However, a significant increase in Na removal by ULNaD (78.1 ± 5.6 mmol) was found compared with both SNaD solutions (12.6 ± 6.4 mmol in 1.36% G solution, p < 0.001; 27.8 ± 5.1 mmol in 2.27% G solution, p < 0.001, respectively). Regarding the latter study aim, in six overhydrated patients with a Na excess, SNaD was replaced with ULNaD once a day for 7 consecutive days. At the end of the study as compared to the pre-values, a significant reduction in body weight (-2.5 ± 1.0%, p < 0.05) and mean arterial pressure (-12.3 ± 3.5%, p < 0.001) was observed. An increased drainage of daily UF volume (+86.5 ± 31.1%, p < 0.05) and a markedly increased daily Na removal (+131.1 ± 24.2%, p < 0.01) were also observed. The results of this study suggest that ULNaD actually facilitates trans-peritoneal Na removal mainly by diffusion force, and that ULNaD could benefit overhydrated patients with a Na excess.

Original languageEnglish
Pages (from-to)188-193
Number of pages6
JournalClinical nephrology
Issue number3
Publication statusPublished - 1996


  • CAPD
  • Ultra-low Na dialysate
  • Volume overload

ASJC Scopus subject areas

  • Nephrology


Dive into the research topics of 'The effect of ultra-low sodium dialysate in CAPD. A kinetic and clinical analysis'. Together they form a unique fingerprint.

Cite this