Volume capacity and pressure characteristics of the continent cecal reservoir

In 11 patients with continent cecostomy, the volume capacity and pressure characteristics of the cecal reservoir were studied at several intervals postoperatively. The reservoir volume stabilized at 400 milliliters four months postoperatively. The basal pressure increased during filling to approximately 9 centimeters of H2O. Pressure waves appeared at all filling volumes in the reservoir but increased in frequency and amplitude with increasing volume. The area underneath the pressure waves was calculated and used as a quantitative measurement of the motor activity. In this manner, a significant increase in motor activity was seen with increasing reservoir volume, although no significant change of motor activity was seen with increasing time after operation. Data from the cecal reservoir were compared with corresponding data from the ileal reservoir obtained in a previous study at our laboratory. This comparison showed a smaller volume capacity and higher basal pressure in the cecal reservoir at identical filling volumes. The motor activity in the cecal reservoir was 20 times greater than that in the ileal reservoir. Thus, the cecal reservoir has a low adaptability to distension compared with the ileal reservoir.