A Comparison between 1.36% and 3.86% Glucose Dialysis Solution for the Assessment of Peritoneal Membrane Function

Abstract

Objective To assess peritoneal membrane function with respect to fluid transport, parameters of low molecular weight solute transport, and estimations of the function of peritoneal water channels, comparing the results from a 1.36%/1.5% glucose solution with those from a 3.86%/4.25% solution in standardized peritoneal function tests. Design The study was performed in 40 stable continuous ambulatory peritoneal dialysis (CAPD) patients [median age 50 years (range: 22 – 74 years); duration of CAPD 9 months (range: 2 – 45 months)] who underwent two standard peritoneal permeability analyses (SPAs) within 1 month. One SPA used 1.36% glucose; the other, 3.86% glucose. Mass transfer area coefficients (MTACs) and dialysate-to-plasma (D/P) ratios were compared for the two solutions. Also, two different methods of estimating aquaporin-mediated water transport were compared: the sieving of sodium (3.86% glucose) and the difference in net ultrafiltration (ΔNUF), calculated as NUF 3.86% SPA – NUF 1.36% SPA. Results Median NUF in the 1.36% glucose SPA was –46 mL (range: –582 mL to 238 mL); in the 3.86% SPA, it was 554 mL (range: –274 mL to 1126 mL). The median difference in NUF for the two SPAs was 597 mL (range: 90 – 1320 mL). No difference between the two solutions was seen for the MTAC of creatinine (11.4 mL/min for 1.36% vs 12.0 mL/min for 3.86%) and absorption of glucose (64% vs 65%, respectively). Also, D/P creatinine was not different: 0.77 (1.36%) and 0.78 (3.86%). However, the ratio of dialysate glucose at 240 minutes and at 0 minutes (Dt/D0) was 0.34 (1.36%) and 0.24 (3.86%), p < 0.01. Values of D/P creatinine from the two glucose solutions were strongly correlated. The intra-individual differences were small and showed a random distribution. Patient transport category was minimally influenced by the tonicity of the dialysate. The minimum D/P Na+ (3.86%) was 0.884, and it was reached after 60 minutes. After correction for Na+ diffusion, D/P Na+ decreased to 0.849 after 120 minutes. The correlation coefficient between the diffusion-corrected D/P Na+ and the ΔNUF was 0.49, p < 0.01. An inverse relationship was present between MTAC creatinine and D/P Na+ ( p < 0.01) This correlation can be explained by the rapid disappearance of the osmotic gradient owing to a large vascular surface area. Such a correlation was not present between MTAC creatinine and ΔNUF. Conclusions We conclude that a standardized 4-hour peritoneal permeability test using 3.86%/4.25% glucose is the preferred method to assess peritoneal membrane function, including aquaporin-mediated water transport. The D/P Na+ after correction for Na+ diffusion is probably more useful for the assessment of aquaporin-mediated water transport than is ΔNUF obtained with 3.86%/ 4.25% and 1.36%/1.5% glucose-based dialysis solutions.

The Association between Glucose Exposure and the Risk of Peritonitis in Peritoneal Dialysis Patients

“…First, Krediet et al (26) found that glucose absorption was approximately 60% after a 4-hour dwell. In addition, Smit et al (47) showed that this was not different when dialysis solutions with different glucose concentrations were used or when patients suffered from diabetes (48). Although the calculation of glucose exposure could be improved by the substitution for 60% in the equation of the individual measured glucose exposure, the use of 60% is easy and fairly accurate (47).…”

“…In addition, Smit et al (47) showed that this was not different when dialysis solutions with different glucose concentrations were used or when patients suffered from diabetes (48). Although the calculation of glucose exposure could be improved by the substitution for 60% in the equation of the individual measured glucose exposure, the use of 60% is easy and fairly accurate (47). Second, the assumption that glucose absorption during a PD dwell follows first order kinetics has previously been established (49,50).…”

Fat tissue and inflammation in patients undergoing peritoneal dialysis

“…The D/Do formula we used was peritoneal absorbed glucose = (1 − D/Do)·x, where ‘x’ is the total amount of glucose infused throughout the day. The D/Do is defined by membrane transport characteristics on a standardized peritoneal equilibration test [ 24 ]; we used the mean value based on peritoneal transport characteristics (0.19, 0.32, 0.44 and 0.55 for high, high-average, low-average and low transporters, respectively) [ 25 ].…”

Monitoring of the peritoneal membrane

“…Theoretically there are many drawbacks of the PET, but in clinical practice the errors are mostly unimportant. Although the D/P Cr is influenced by convective transport from the circulation to the peritoneal cavity [ 102,103 ], no differences were found for the D/P ratios of urea and creatinine between a PET using 1.36/1.5% and 3.86/4.25% [ 104 ] or a PET with 2.27/2.5% and 3.86/4.25% [ 105,106 ]. Despite the advice that the PET should be performed after a long dwell, D/P ratios of low-molecular-weight solutes are not influenced by a short preceding dwell [ 107–109 ].…”