The peritoneal kinetic study performed with hypertonic glucose permits better evaluation of UF capacity and determination of sieving of sodium

Abstract

The use of solutions containing hypertonic glucose (3.86%/4.25%) has been postulated as the method of choice for study the peritoneal function, and permits a better evaluation of the ultrafiltration (UF) capacity. The aim of our study was to analyze the UF capacity and its relation with the peritoneal permeability and sieving of sodium, performing the peritoneal kinetic study with hypertonic glucose solutions. We performed 184 peritoneal kinetic studies with hypertonic glucose solutions in stable patients on peritoneal dialysis (PD), with a mean time on PD of 16 +/- 22 months. We measured the mass transfer coefficient of creatinine (CrMTC), dialysate to plasma ratio of creatinine (D/PCr), UF capacity and sieving of sodium at 60 minutes (difNa60). The mean values were: CrMTC: 9.1 +/- 4.5 ml/min, D/PCr: 0.71 +/- 0.09, UF 759 +/- 233 ml/4 h and difNa60: 4.7 +/- 2.3. The best multivariate model that predicts the UF capacity included: difNa60, CrMTC, age and time on PD (r = 0.57; p > 0.0001). In patients with UF lower than 600 ml/4 h (Percentil 25) the correlation between UF and CrMTC was lost, but remains the correlation with difNa60 (r = 0.48). The patients with previous peritonitis (n = 38) showed no differences in UF, CrMTC or D/Pcr, but the had lower difNa60 (3.7 +/- 2.8 vs. 4.9 +/- 2.1; p = 0.002) than the remaining patients. The peritoneal kinetic study performed with hypertonic glucose allows to standardize the UF capacity and by determination of sieving of sodium, the early detection of water transport alterations, before the UF capacity and small solutes permeability alteration develops.