Comparison between Bicarbonate/Lactate and Standard Lactate Dialysis Solution in Peritoneal Transport and Ultrafiltration: A Prospective, Crossover Single-Dwell Study

Abstract

Objective It has been proposed that biocompatible bicarbonate/lactate based (Bic/Lac), physiologic-pH peritoneal dialysis (PD) solutions will be beneficial in long-term PD. However, we do not yet have detailed knowledge concerning the comparative physiology of buffer transport for these new solutions and their impact on underlying peritoneal transport of solutes and ultrafiltration (UF). The purpose of this study was to investigate the profile of buffer handling and peritoneal membrane transport characteristics during a single dwell of the new Bic/Lac-based versus standard lactate-based (Lac) PD solution. Methods In this prospective crossover study, we compared a 25 mmol/L bicarbonate/15 mmol/L lactate buffered, physiologic pH, low glucose degradation product (GDP) solution (Physioneal; Baxter Healthcare, McGaw Park, Illinois, USA) with a standard lactate buffered, acidic pH, conventional solution (Dianeal; Baxter). 18 patients underwent two peritoneal equilibration tests (PETs) with 2.5% Dianeal and 2.5% Physioneal separated by 1 week. Buffer transport, mass transfer area coefficients (MTACs), solute transport, and UF were determined for the two PETs. All bags were weighed by a nurse before instillation and after drainage to assess the net UF in each dwell. Results 18 patients that met the inclusion criteria were enrolled in this study. Whereas intraperitoneal pH remained constant at 7.52 ± 0.11 throughout the dwell with the Bic/Lac solution, pH was still in the acidic range with the Lac solution after 1 hour (7.29 ± 0.13, p < 0.001); this difference disappeared after the second hour of dwell. The MTACs for creatinine (10.68 ± 3.66 vs 10.73 ± 2.96 mL/minute/ 1.73 m2, p > 0.05) and urea (27.94 ± 10.50 vs 27.62 ± 6.95 mL/min/1.73 m2, p > 0.05), for Bic/Lac versus Lac respectively, did not differ between these two solutions; transport of glucose and other solutes was also similar. However, after a 4-hour dwell with Bic/Lac solution, net UF was significantly lower than that observed with Lac solution (274.2 ± 223.3 mL vs 366.1 ± 217.3 mL, p = 0.026). Conclusions Compared to standard Lac-based solution, Bic/Lac based, pH neutral, low-GDP solution avoids intra-peritoneal acidity. Peritoneal mass transport kinetics are similar for small solutes. Net UF is significantly lower with Bic/Lac solution; the mechanism for this is unclear.

Comparison of Longitudinal Membrane Function in Peritoneal Dialysis Patients According to Dialysis Fluid Biocompatibility

“…Both show a decrease after 3 to 4 years. The developments in small solute transport are likely caused by neoangiogenesis (20,36), leading to an enlarged peritoneal vascular surface area (37). Besides cytotoxic effects of GDPs on the mesothelial cell layer (31,(38)(39)(40)(41), a more likely explanation is their promotion of the formation of advanced glycosylation end products (AGEs) that accumulate in the peritoneal vascular wall and induce neoangiogenesis (32,33).…”

The Effect of Low-GDP Solution on Ultrafiltration and Solute Transport in Continuous Ambulatory Peritoneal Dialysis Patients

“…It has been suggested that vasoactive substances may influence blood flow or the permeability of the peritoneal vascular bed (9,19,20). Fang et al (11) reported that, compared with a high-GDP exchange, a single exchange of low-GDP solution (Physioneal: Baxter Healthcare Corporation, Deerfield, IL, USA) resulted in a lower UFV and similar solute transport during a 2.5% glucose PET. Kim et al (18) reported that an increased D/P Cr (and consequently, a lower UFV) in a low-GDP group (Stay • Safe Balance) might provide a lower risk of intravascular volume depletion and a higher probability of RRF preservation.…”

“…Venous blood samples drawn at 0, 120, and 240 minutes were assayed for glucose, urea, and creatinine. Creatinine measurements were corrected for the presence of glucose (11).…”

“…After the complete drain at 4 hours, the drain bag was weighed as the drainage volume, with the flush in and with no compensation for the flush volume. The UFV was calculated as the drain volume minus the instillation volume (11).…”

“…Previous studies have demonstrated that a neutral-pH dialysate low in GDPs allows for preservation of the peritoneum, but investigations into the effects of low-GDP dialysate on ultrafiltration (UF), solute transport, and body fluid management have been limited (9,11,12). To address that issue, we conducted a prospective study to analyze the clinical consequences of low-GDP dialysate with respect to UF, solute transport, and body fluid.…”