Ambulatory manometric examination in patients with a colonic J pouch and in normal controls.

Anorectal function after anterior resection may be impaired as a result of reduced luminal capacity in the pelvis. The aim of this study was to evaluate the colonic J pouch neorectum by means of ambulatory manometry. Twelve patients with a colonic pouch following anterior resection and seven healthy controls were studied for a median of 6 (range 6-24) h using a probe with two pouch-rectal and two anal canal transducers. Records were interpreted by visual inspection. Pressure values and wave frequencies were determined by software analysis. Pouches had been functioning for a median of 32 (range 11-55) months. All patients with a pouch had an acceptable stool frequency. Seven of 12 patients complained of incomplete evacuation. Resting anal canal pressure (73 versus 100 cmH2O), pouch-rectal pressure (29 versus 15 cmH2O) and anal canal pouch-rectal pressure gradients (60 versus 85 cmH2O) were similar in patients and controls. The frequency of slow-wave activity in patients with a pouch was significantly lower than that in controls (7 versus 16 cycles per min, P = 0.001). Coordination between the colonic J pouch and the anal canal, in the form of sampling episodes, was observed in more than half of the patients with a functioning pouch. Large isolated contractions (pressure greater than 30 cmH2O and lasting longer than 20 s) and rhythmic contractions were the most frequent pattern of pouch motility.