Urinary Retention After Midurethral Sling: RCT of Retropubic Lidocaine Versus Saline

IMPORTANCE: Postoperative urinary retention (POUR) is common following midurethral sling (MUS) placement, and can be distressing for patients. OBJECTIVE: The objective of this study was to compare the effect of retropubic lidocaine versus saline placebo on POUR following MUS placement. STUDY DESIGN: This double-blind, placebo-controlled trial randomized women undergoing MUS placement with or without anterior repair to 20 mL of retropubic 0.5% lidocaine+epinephrine (lidocaine) versus normal saline+epinephrine (saline). Primary outcome was a failed postoperative retrograde voiding trial. Visual Analog Scales (VAS) were administered 2 and 6 hours postoperatively, and 7-day diaries assessed pain and analgesic use. We required 150 participants to detect a 20% reduction in POUR with 80% power, two-sided alpha of 0.05, and 5% loss to follow-up. RESULTS: Between 2020 and 2024, 150 participants were randomized, 75 in each arm. Demographic and surgical characteristics were similar with mean age 51.5 years (44-63) and body mass index 29.0 (25.7-33.6). Participants were predominantly White (94.0%), postmenopausal (54.0%), and multiparous (95.3%). POUR was similar between groups (lidocaine 20.0% vs saline 18.7%, P = 0.84). Saline participants had significantly higher VAS scores at 2 and 6 hours postoperatively (2 h 21 [10-42] vs 11 [0-28], P = 0.008; 6 h 25 [13-50] vs 18 [9-33], P = 0.03), used more nonsteroidal anti-inflammatory drugs (NSAIDS) on POD 1 (76.2% vs 52.3%, P = 0.005) and reported higher levels of "worst pain in the first 24 hours" (6 [3.5-7.5] vs 4 [3-6], P = 0.013). At 6 weeks postoperatively, more lidocaine participants were satisfied or very satisfied with the outcome of their surgery (90.7% vs 77.3%, P = 0.03). CONCLUSIONS: Compared with saline, retropubic lidocaine at the time of midurethral sling placement does not result in significantly higher rates of POUR, but significantly improves acute postoperative pain, NSAID use, and satisfaction with surgical outcomes.