[Absence of a direct effect of peritoneal dialysate on venous lower limb flow]

In order to verify if the presence of 21 of fluid in the peritoneum is likely to produce a slowing of the venous flow in the lower limbs, 34 patients suffering from end stage chronic renal failure and treated by continuous ambulatory peritoneal dialysis (CAPD) were followed up for two years by means of noninvasive methods. The maximum femoral venous flow velocity before and during CAPD was evaluated using Doppler effect, in 2 positions of the patients (recumbent or upright), and with or without dialysate (abdomen full or empty). The venous distensibility and the maximum venous outflow were evaluated using venous occlusion plethysmography in the recumbent position. Despite a decrease in mean arterial blood pressure (before the start of CAPD: 116.0 +/- 3.7 mm Hg; after 2 years of CAPD: 104.3 +/- 3.2 mm Hg, p less than 0.02), there was no significant slowing of the venous limb flow during the two years of treatment by CAPD, and in no case did the peritoneal fluid constitute a mechanical obstruction.