Effect of Increased Dialysate Volume on Peritoneal Surface Area among Peritoneal Dialysis Patients

Abstract

Abstract. Large dialysate volumes are often required to increase solute clearance for peritoneal dialysis patients. The resulting increase in solute clearance might be attributable to an increased plasma-to-dialysate concentration gradient and/or to an increased effective peritoneal surface area. One of the factors affecting the latter is the peritoneal surface area in contact with dialysate (PSA-CD). The aim of this study was to estimate the change in PSA-CD after a 50% increase in the instilled dialysate volume for patients undergoing peritoneal dialysis. PSA-CD was estimated by using a method applying stereologic techniques to computed tomographic (CT) scans of the peritoneal space. The peritoneal cavity of 10 peritoneal dialysis patients was filled with a solution containing dialysate, half-isotonic saline solution, and contrast medium. Peritoneal function tests and CT scanning of the abdomen were performed twice for each patient (with an interval of 1 wk), after instillation of a 2-or 3-L solution. Scanning of thin helical CT sections was performed, and 36 random sections of the abdomen were obtained after reconstruction. A grid was superimposed on the sections. The surface area was estimated by using stereologic methods.

Correlating structure with solute and water transport in a chronic model of peritoneal inflammation

“…We would argue that if there is no contact of the dialysis fluid with the peritoneum, then there can be no mass or fluid transport from the underlying microvasculature. Indeed, animal and clinical studies have demonstrated the quantitative importance of the surface contact area (1,10) to mass transfer. The contact area (10, 11) depends on the volume instilled, the size, position, and the intrinsic properties of the peritoneum, which may be altered by the experimental treatment.…”

Diálisis peritoneal automática adaptada: un método de prescripción eficaz, eficiente y seguro

“…Siguiendo con esta prescripción, mayores volúmenes de llenado, provocan que la superficie de la membrana peritoneal en contacto con el líquido peritoneal sea mayor, consiguiendo una mejor eliminación de toxinas urémicas. Por consiguiente, volúmenes menores logran una UF más efectiva, debido a una presión intraperitoneal menor y a una disminución de la reabsorción del líquido de diálisis (3,6,11) . Esta nueva forma de pautar la DPA ha sido denominada "adapted automated peritoneal dialysis" (APD-A), diáli-sis peritoneal automatizada adaptada, por Fischbach et al…”

Exact and Numerical Solutions of a Spatially-Distributed Mathematical Model for Fluid and Solute Transport in Peritoneal Dialysis

“…In particular, using the value of the fluid flux j U at the point x " 0, one may calculate the ultrafiltration flow. Total fluid outflow from the tissue to the cavity (ultrafiltration), calculated assuming that the surface area of the contact between dialysis fluid and peritoneum is equal to 5ˆ10 3 cm 2 (a typical value for this surface [19]), is 1.0, 1.6 and 6.0 mL/min for the the Staverman reflection coefficients 0.001, 0.002 and 0.01, respectively. Thus, the ultrafiltration is about 5% higher than the one obtained in [11].…”