Prospective evaluation of ileoanal pouch characteristics measured by barostat

PURPOSE: The aim of this study was to evaluate pouch sensory and motor characteristics prospectively during the first postoperative year and to compare those with rectal characteristics. METHODS: Twelve patients with an ileoanal J-pouch were studied at 3 and 12 months postoperatively. The results were compared with those obtained in 12 healthy controls. Visceral compliance was assessed using an electronic barostat by a pressure distention procedure, during which sensitivity was also scored by visual analog scales. The response to a meal was assessed during set pressure. RESULTS: During the first postoperative year, pouch compliance increased significantly from 7.2 +/- 0.6 to 10.7 +/- 0.9 ml/mmHg (rectal compliance 10.6 +/- 1.1 ml/mmHg). The increase in pouch compliance significantly influences the 24-hour stool frequency (r(2) = 0.42). Visceroperception scores remained unchanged. Postprandial decrease in intrabag volume was more pronounced in patients (45 +/- 13 percent at 3 months, 32 +/- 15 percent at 12 months) than in controls (9 +/- 6 percent, P <0.05), and residual postprandial bag volumes were significantly lower in patients at 3 months compared with patients at 12 months. CONCLUSIONS: Ileoanal pouch compliance increases significantly during the first postoperative year to values in the range of rectal compliance. The increase in pouch compliance is related to a decrease in 24-hour stool frequency. Postprandial bag volumes increase during the first postoperative year but remain significantly smaller than in the rectum. Pouch sensitivity does not change