Pressure studies on the continent reservoir ileostomy.

The continent Koch ileostomy constitutes a major improvement in the quality of life for patients requiring an ileostomy. Complete continence is achieved in most patients, although the mechanisms underlying this control of fecal flow are poorly understood. Pressure studies on the pouch, the nipple valve and the outlet were preformed and results showed the presence of a high pressure zone in the nipple valve relative to the pouch. The high pressure zone maintained, even when the intra-abdominal pressure was raised or during contractions of the pouch, and most likely, contributes to continence. The pressure in the nipple valve and outlet was further intermittently increased by spontaneously occurring phasic and tonic contractions. Distention of the pouch with air caused a tonic contraction that was first recorded from the pouch and that traveled aborally along the intestinal layers of the intususcepted nipple valve and the outlet. By frequent emptying of the pouch, such contractions are avoided, and the risk of desusception of the nipple valve may be reduced.