Airway Management Technique and Acute Urinary Retention After Midurethral Sling

Objectives: To compare the proportion of patients with acute postoperative urinary retention (APUR) after exposure to intraoperative airway management with a laryngeal mask airway (LMA) versus other in women undergoing midurethral sling procedures. Secondary objectives included identifying factors associated with postoperative urinary retention.

Methods: Retrospective cohort of female patients undergoing outpatient retropubic midurethral sling procedures by any of the 7 fellowship trained Urogynecologists at a single academic hospital from January 2019-January 2022. Patients were excluded if they had a diagnosis of neurogenic bladder, sling reoperation for retention, indication for prolonged indwelling catheterization, or incomplete documentation of the primary outcome (failed recovery room trial of void (TOV)) or exposure (airway management technique: LMA versus other (other defined as endotracheal tube (ETT), neuraxial anesthesia, intravenous sedation). Demographic and clinical information were extracted from the medical record. To detect a 15% difference in APUR between groups (α 0.05, β 0.20, 3:1 treatment ratio), 372 patients were required. Chi-square tests were performed and regression models applied.

Results: Three-hundred seventy-two women with mean age 52.16+11.51 and mean BMI 31.06+6.88 met inclusion criteria. Two-hundred sixty-four patients (264/372, 71.0%) were exposed to LMA, 84/372 (22.6%) to ETT, 23/372 (6.2%) to neuraxial anesthesia and 1/372 (0.02%) to intravenous sedation. Patients exposed to LMA had a lower mean weight (76.9+16.8 kg versus 91.43+21.3 kg other), a lower prevalence of reflux (63/264, 23.9% versus 57/108, 52.8% other) and a greater proportion had no comorbidities (137/264, 51.9% versus 31/108, 28.7% other) or prior surgeries (199/264, 75.4% versus 73/108, 67.6% other, all p< 0.05). There were no differences in other demographic and clinical variables between groups. Overall, 68/372 (18.3%) experienced APUR, with retention occurring in 38/264 (14.4%) exposed to LMA, 22/84 (26.2%) to ETT, 8/23 (34.8%) to neuraxial anesthesia and 0/1 (0%) to intravenous sedation. There was a significant difference between groups regarding the primary outcome of APUR (38/264, 14.4% LMA versus 30/108, 27.8% other, p< 0.001). When comparing LMA to ETT alone, a significantly greater proportion of patients exposed to ETT developed APUR (38/264, 14.4% LMA versus 22/84, 26.2% ETT, p=0.012). A greater proportion of patients exposed to ETT received glycopyrrolate (63/84, 75% ETT versus 78/264, 29.7% LMA), succinate (77/84, 91.7% ETT versus 2/264, 0.8% LMA), and rocuronium (77/84, 91.7% ETT versus 1/264, 0.4% LMA) in the operating room (all p < 0.001). On multivariable logistic regression, the differences in APUR between airway management techniques were not statistically different when controlled for the administration of glycopyrrolate, succinate, and rocuronium.

Conclusions: In this cohort, not receiving LMA anesthesia was associated with higher likelihood of APUR, though not statistically significant when controlled for specific intraoperative medications, suggesting possible association between anesthetic medication administration and APUR.