71: Effect of pudendal blockade on bladder emptying after midurethral sling: A randomized controlled trial

Abstract

To evaluate the effect of bilateral pudendal nerve blockade on immediate postoperative bladder emptying following midurethral sling. We performed a double-blinded, randomized, placebo-controlled trial of women undergoing a midurethral sling procedure between October 2017 and February of 2019. Women > age of 18 were eligible if they were undergoing a midurethral sling with no concomitant procedures and had no preoperative urinary retention. Subject demographics and medical conditions that may impact bladder emptying were recorded pre-operatively. Participants were randomized to a bilateral pudendal block of either 20 cc of 0.25% bupivacaine or 20 cc of normal saline. Randomization was performed using a 1:1 ratio and a block randomization scheme. The study medications were prepared in standard 10 cc syringes with blinding of both the participant and surgeon maintained throughout the study. After induction of anesthesia, a pudendal block was administered by a urogynecology attending or fellow prior to any incisions. No other local anesthesia was used. The primary outcome was the rate of passing a standardized void trial. Secondary outcomes included perioperative pain scores, analgesia use and complications. Ninety-one subjects were enrolled in the study. One patient had a delayed void trial on postoperative day one, leaving 90 subjects for the final analysis. Demographic and perioperative characteristics were similar between the groups. Adjusted logistic regression showed the administration of bupivacaine pudendal block worsened postoperative bladder emptying (OR=0.32, p=0.02 adjusted for age, BMI, and comorbidities). Postoperative pain scores and analgesia use were similar between the groups. Postoperative complications including UTI, mesh exposure, pelvic hematoma or urinary retention within 6 weeks were similar between the groups. Our prospective trial demonstrates that a bilateral pudendal blockade prior to midurethral sling procedure worsens postoperative bladder emptying.