Bicarbonate versus Lactate-Based Capd Fluids: A Biocompatibility Study in Rabbits

Abstract

Previous in vitrobiocompatibility studies have shown bicarbonate-based continuous ambulatory peritoneal dialysis (CAPD) fluids to be superior to those based upon lactate/acetate. To evaluate these findings in vivo, 41 rabbits were subjected to CAPD for four weeks in a randomized prospective study using either Dianeal, a commercially available dialysis fluid containing lactate, or 87b, a bicarbonate-based CAPD fluid. Ten rabbits with CAPD catheters, which were flushed with a heparin solution every 36 hours, served as controls. None of the control rabbits showed clinical or histopathological signs of peritonitis, while 8 of 20 in the Dianeal group and 6 of 21 in the 87b group contracted peritonitis. Four rabbits in the Dianeal group had to be sacrificed early due to severe peritonitis. Post mortem examinations, including scanning and light microscopy, did not reveal any macroscopic or microscopic differences among the three groups of noninfected animals. No significant distinctions between the groups could be made for body temperature, weight gain, dialysate volume, dialysate differential leukocyte count, dialysate protein content, and food intake during the course of the study. In conclusion, the present animal model did not reveal any major difference in the biocompatibility between the lactate and the bicarbonate-based CAPD fluids.

Peritoneal Sclerosis: One or Two Nosological Entities?

“…The features of SS can also be reproduced in rats after PD (59,63,(69)(70)(71), with no need for the action of any other agent on the peritoneum. These phenomena are constant and reproducible, making these models suitable for comparing the biocompatibility of different PD solutions (63,64,67,68,(71)(72)(73)(74)(75). No case of SS has ever been described in the absence of PD.…”

“…Rabbits treated with PD for 3-4 months have all the typical mesothelial and submesothelial morphologic modifications induced by PD in humans, including some features of SS (64,65,67,68). The features of SS can also be reproduced in rats after PD (59,63,(69)(70)(71), with no need for the action of any other agent on the peritoneum.…”

Conventional versus biocompatible peritoneal dialysis fluids: more questions than answers?

“…The mesothelial viability was better upon 30-day exposure to bicarbonate-buffered PD fluids [ 28 ] or 12-week exposure to lactate/bicarbonate-buffered PD fluids [ 29 ]. Other researchers [ 25 , 30 , 31 ], however, did not find any differences in mesothelial morphology between both types of fluid in rats and rabbits.…”

Biocompatibility of a new PD solution for Japan, Reguneal™, measured as in vitro proliferation of fibroblasts

“…Of note, the wholesale replacement of lactate by an equivalent amount of bicarbonate results in a solution pCO 2 of 200-300 mmHg, as predicted by the Henderson-Hasselbalch equation. In turn, this can lead to abdominal discomfort [36], lowering of intracellular pH, and impairment of cellular functioning: in vitro experiments demonstrate that migration and function of polymorphonuclear cells is affected by the base balance, with optimal performance observed in the setting of a bicarbonate and reduced lactate formulation, compared to bicarbonate alone [35,[37][38][39][40][41]. With Reguneal™, the buffer formulation is the bicarbonate-based buffer with reduced lactate, thereby resulting in a neutral pH without paradoxical intracellular acidification, and improved biocompability.…”