Influence of pH on Reservoir Mucosal Absorption/-Secretion and Tubular and Glomerular Function. Studies in Patients with a Continent Ileal Reservoir for Urinary Diversion

Abstract

Ten patients with a continent ileal reservoir for urinary diversion were studied regarding transmucosal fluxes of water and electrolytes at different pH. The urine was by-passed the reservoir via a Foley catheter. The experiment set-up was designed to exclude urine from reservoir mucosa exposition during the study. Test solutions of pH 4 and pH 7 with electrolytes and a non-absorbable volume marker (PEG MW 4000) were instilled into the empty reservoir. The influence of altered pH on the flow of water and Na,⁺,K⁺ and Cl^- across the reservoir mucosa was analysed. The maximal concentration ability after intranasal desmopressin (Minirin^®), the creatinine and Na-clearance as well as the fractional Na-excretion were calculated from measurements on the by-passed urine. The results showed a secretion of water, Na⁺ and Cl^- into the reservoir while the K⁺ content was constant. The mucosal flows of water and electrolytes were not affected by alterations in reservoir pH. Maximal concentration ability appeared to be reduced compared to normals. Fractional Na excretion was within normal limits.

Keywords:

• urinary diversion
• continent ileal reservoir
• kidney function
• mucosal flow of water
• mucosal flow of electrolytes