Mechanisms of Urinary Continence: An Animal Model to Study Urethral Responses to Stress Conditions

Publisher Website
Google Scholar
Abstract
Under conditions of stres, the urethral sphincteric mechanism [human] has to compensate a passive bladder pressure rise induced by increase in intraabdominal pressure. To evaluate the various closure mechanisms contributing to urethral response to stress, a female dog model was subjected to the physiologic stress condition triggered by sneezing. Vesical, rectal and 4 urethral pressures during after transection of the bladder and urethra and with the abdomen open. The effects of the Crede maneuver and of manual squeezing of the surgically exposed bladder were also recorded. The existence of a 2-component urethral closure mechanism under stress is supported; the proximal closure mechanism of the smooth muscular, intrapelvic urethra is from passive transmission of abdominal pressure.It is apt to balance a passive increase in bladder pressure and maintain proximal closure pressure during stress. The distal closure pressure mechanism is capable of exceeding passive increase in bladder pressure and augments closure pressure during stress.