Rectosigmoid urinary diversion: the functional significance of creating an intussuscepted colorectal valve.

Purpose: We assess the functional importance of a colorectal valve in patients with rectal urinary diversion.

Materials And Methods: A retrospective evaluation of 87 patients with an anal sphincter controlled bladder substitute was performed. Of these patients 42 had colorectal valves and 45 did not. Evaluation included serum chemistry studies and arterial blood samples to study the impact of the colorectal valve on homeostasis.

Results: There was a statistically significant difference between the 2 groups in pH, carbon dioxide partial pressure, bicarbonate, base excess and chloride in favor of patients with a colorectal valve.

Conclusions: The difference between the groups was reduction of the surface area available for reabsorption when a valve is constructed. This finding is of particular importance among patients with a long life expectancy. Prophylactic alkalization is necessary in cases without valve reconstruction.