ANAL AND RECTAL MOTILITY RESPONSES TO DISTENSION OF THE URINARY-BLADDER IN MAN

Recto-anal motility response to bladder distension was studied under g eneral anaesthesia in 12 patients undergoing intestinal resection for Crohn's disease of the small intestine or colonic cancer. The effect o f epidural an aesthesia on anal tone and on the motility response to b ladder distension was studied in six of these patients. An anal pressu re increase on bladder distension was observed in all individuals. No motility response was noted in the rectum. The anal pressure response to bladder distension was abolished by epidural anaesthesia. It was co ncluded that anal pressure in man under general anaesthesia was tonica lly influenced by the thoracolumbar sympathetic outflow. An excitatory vesico-anal reflex was demonstrated. It appears as this reflex is med iated via the spinal cord.