THE IMMEDIATE EFFECT OF COLPOSUSPENSION ON RESTING AND STRESSED URETHRAL PRESSURE PROFILES IN ANESTHETIZED INCONTINENT BITCHES

The aim of this study was to document what changes in the resting and stressed urethral pressure profile occur in the incontinent bitch with urethral sphincter mechanism incompetence (SMI) immediately after col posuspension. Resting and stressed subtracted simultaneous urethral pr essure profilometry was performed immediately pre- and postcolposuspen sion in 26 bitches diagnosed with SMI. All of the urethral pressure pr ofiles were measured in anaesthetized bitches using a standard techniq ue and two orientations of the catheter transducers (dorsal and left). Readable pre- and postoperative urethral pressure profiles were obtai ned in 20 of the 26 bitches. Subjective and objective evaluation of th e profiles showed significant differences in the profiles pre- and pos tcolposuspension. Immediately postoperatively there were significant ( P < .05) increases in functional profile length, maximum urethral clos ure pressure (MUCP), and distance between the bladder neck and the fir st negative respiratory peak and stressed spike. There was a significa nt (P < .001) decrease in the percentage of negative spikes extending below the resting intravesical pressure on the subtracted profile. The pressure transmission profiles were significantly (P < .001) altered by surgery. The findings presented support the hypothesis that colposu spension may restore continence by increasing pressure transmission to the proximal urethra and bladder neck. The results also suggest that immediately after surgery functional urethral length and urethral resi stance are increased. (C) Copyright 1994 by The American College of Ve terinary Surgeons