[Sphincter function following colo-anal anastomosis]

The effect of colo-anal anastomosis (CAA) on the function of the anal sphincters was assessed in 27 cases by interview, sphincter manometry and a retention test. During an observation period of 3-12 months after closure of colostomy, the percentage of patients with perfect continence increased from 50 to 80%, of those with solid stool consistency from 30 to 90% and of those with solid stool consistency from 30 to 90% and of those with less than 5 b.o./day from 30 to 80%. The operation resulted in a significant reduction of the length of the anal canal from 4.0 +/- 0.3 to 1.7 +/- 0.2 cm (p less than 0.001) and a significant reduction of the resting tone from 85.5 +/- 7.9 to 30.3 +/- 6.1 cm H2O (p less than 0.001). The contraction pressure was hardly influenced, the recto-anal inhibition reflex was temporarily lost. Minute preoperative assessment of a normal sphincter function with anal manometry is an essential prerequisite for the evaluation of the indication for a CAA.