The Mainz pouch II (sigma rectum pouch).

A low pressure rectosigmoid reservoir for urine is created obviating the need for colostomy, augmentation or extensive bowel surgery. Antimesenteric splitting of the intestine at the rectosigmoid junction and subsequent side-to-side anastomosis are performed. Urodynamic data demonstrate that the detubularization is effective in rendering high pressure bowel contractions ineffective. Without the risk of damaging the mesentery the pouch is fixed at the promontory, which lessens the risk of ureteral kinking and upper urinary tract dilatation. The technique is indicated not only in cases of failed ureterosigmoidostomy but also for primary urinary diversion. All 47 patients who underwent the operation were evaluable with a followup of 1 to 20 months (mean 10 months). All patients are continent during the daytime with a mean emptying frequency of 5 times. All but 1 elderly woman are dry at night with a mean frequency of 1 episode. With the reservoir full the basal pressure was 24 cm. water and the highest peak pressure recorded was 35 cm. water. The low pressure improves continence, protects the upper urinary tract and even allows dilated ureters to be implanted.