Effects of vaginal hysterectomy on anorectal sensorimotor functions - a prospective study

Background While bowel and bladder dysfunction are recognized consequences of a radical hysterectomy, the effects of a simple hysterectomy on anorectal sensorimotor functions, particularly rectal sensation, vary among studies and the effects on rectal compliance remain unknown. Our aims were to prospectively evaluate anorectal sensorimotor functions before and after a hysterectomy. Methods Anal pressures, rectal compliance, capacity, sensation, and bowel symptoms were assessed before, at 2months, and at 1year after a simple vaginal hysterectomy for benign indications in 19 patients. Rectal staircase (0-44mmHg, 4-mmHg steps), ramp (0-200mL at 50, 200 and 600mLmin ^-1) and phasic distentions (8, 16, and 24mmHg above operating pressure) were performed. Key Results Anal resting (63±4 before, 56±4mmHg after) and squeeze pressures (124±12 before, 124±12mmHg after), rectal compliance and capacity (285±12 before, 290±11mL 1year after), and perception of phasic distentions were not different before vs after a hysterectomy. Sensory thresholds for first sensation and the desire to defecate were also not different, but pressure and volume thresholds for urgency were somewhat greater (Hazard ratio=0.7, 95% CI [0.5, 1.0]) 1year after (vs before) a hysterectomy. Rectal pressures were higher (P<0.0001) during fast compared with slow ramp distention; this rate effect was greater at 1year after a hysterectomy, particularly at 100mL (P=0.04). Conclusions & Inferences A simple vaginal hysterectomy has relatively modest effects (i.e., somewhat reduced rectal urgency and increased stiffness during rapid distention) on rectal sensorimotor functions.