Dynamic maximum urethral closure pressures measured by high-resolution manometry increase markedly after sling surgery

Abstract

Advanced HRM technology to measure MUCPs under cough and strain conditions without withdrawal techniques provides new insights into the continence mechanism after tension-free MUS: MUCPs do not change at rest but do increase significantly during cough and strain maneuvers.

The female continence mechanism measured by high resolution manometry: Urethral bulking versus midurethral sling

“…The most common procedure to treat incontinence when related to urethral hypermobility is the midurethral sling (MUS). Work by our group has already demonstrated that after MUS placement there is no significant change in maximum urethral closure pressures (MUCP) at rest, but marked increases (up to 60 cm H 2 O) with cough, and strain . These findings suggest that the MUS does not affect the urethra at rest, but functions by augmenting the MUCP during cough, and strain maneuvers.…”

“…Each study subject completed three validated incontinence symptom questionnaires before and 6 weeks after urethral bulking injection: the Incontinence Severity Index (ISI, scale 0‐12), the Incontinence Impact Questionnaire Short Form (IIQ‐7, scale 0‐100), and the Urogenital Distress Inventory short form (UDI‐6, scale 0‐100) . This urethral bulking cohort was compared to a cohort of 26 patients who underwent the same HRM measurements before and after MUS placement . The study was approved by the University of California San Diego Institutional Review Board and written informed consent was obtained from each participant.…”

“…The HRM catheter is 2.75 mm in diameter (approximately 8 F) and has circumferential pressure sensors along 26.5 cm of its length . The miniature solid‐state sensors are 4 mm long with 2 mm of active sensing area separated by 3 mm of flexible molding giving a 7.5 mm on center spacing between each of the 36 sensors . Each individual sensor has 16 pressure‐sensitive segments circumferentially distributed around it (Figure ).…”

“…Measurements were taken in the supine position after completely draining the bladder of urine and then filling the bladder with 250 cc of sterile water. The HRM catheter was placed such that the tip was 5 cm inside the bladder . Bladder and urethral pressure measurements were taken three times at rest, during three coughs, and during three strain maneuvers .…”

“…The HRM catheter was placed such that the tip was 5 cm inside the bladder . Bladder and urethral pressure measurements were taken three times at rest, during three coughs, and during three strain maneuvers . For strain maneuvers, subjects were instructed to bear down or push as though trying to push out a baby or have a bowel movement .…”