10: Preoperative levator ani muscle and pudendal nerve injections for pain control after vaginal reconstructive surgery: A three-arm randomized controlled trial

Abstract

To test the hypothesis that preoperative levator ani muscle (LAM) and transvaginal pudendal nerve (PN) injections with bupivacaine and dexamethasone would improve postoperative pain after vaginal apical prolapse repair. We performed a 3-arm, double-blind, randomized trial of bilateral LAM and PN injections administered prior to vaginal apical support procedures [uterosacral ligament suspension (USLS), sacrospinous ligament fixation (SSLF), levator myorrhaphy or colpocleisis] under standardized general anesthesia. Women were randomized to 0.9% saline, 0.25% bupivacaine, or 0.25% bupivacaine with 4mg dexamethasone injected into 4 sites (bilateral LAM via transobturator approach and transvaginal PN blocks). Primary outcome was a numeric rating scale (NRS) pain score on postoperative day (POD) 1 (higher scores = worse pain). Secondary outcomes included same day discharge, voiding status, analgesic use, nausea/vomiting, activity level, and adverse events. Women were followed for 12 weeks. Twenty-one per arm were required to detect a 2-point change on the NRS (a=0.05, 90% power). Of 281 women screened, 139 (49.5%) were eligible and 75 (26.7%) were randomized with no differences in demographics or procedural characteristics among study arms. There were no significant differences in POD 1 NRS pain scores or other secondary outcomes among study arms (Table). One week after surgery, 73.0% were at or better than their preoperative activity level, increasing to 83.3% by 12 weeks. There was no difference in timing of return to baseline activity among study arms (p>0.25). At POD 3, SSLF had significantly higher NRS scores than USLS or obliterative procedures [4.5 (4.0-7.0) vs. 2.0 (0.5-4.75) vs. 2.5 (2.0-5.0), p = 0.049]. A trend towards higher NRS scores for SSLF occurred at 6 hours and POD 1 (p = 0.09 and p = 0.06). In women undergoing vaginal native tissue apical prolapse repair, preoperative LAM and PN injections with bupivacaine and dexamethasone did not improve postoperative pain control. Most women were at or better than their preoperative activity level 1 week after surgery. SSLF may induce more postoperative pain than USLS or obliterative procedures.