Volume Capacity and Pressure Characteristics of the Continent Ileostomy Reservoir

Abstract

The volume capacity and the pressure characteristics of the ileal reservoir were studied at intervals postoperatively in 28 patients with continent ileostomy. The reservoir volume increased during the first 6 mo. from 100 ml to .apprx. 700 ml, after which it remained stable. The basal pressure increased during filling to a maximum of roughly 10 cm H2O. Under physiological conditions the basal pressure was .apprx. 4 cm H2O before emptying. Two types of pressure waves occurred, small pressure fluctuations with a frequency of 7-8/min and larger phasic waves appearing when .apprx. 40% of the reservoir volume capacity was reached. The occurrence of both types of pressure waves decreased with time. The total motor activity, expressed as the area underneath the pressure waves, decreased considerably during the 1st yr after operation, indicating an adaptation of the intestinal smooth muscle to distension. The ileal reservoir constructed in this manner evidently is a low-pressure reservoir.