Ureteroscopy under conscious sedation: A proof-of-concept study

Introduction: Ureteroscopy (URS) is commonly performed under general anesthesia (GA) to maximize patient tolerability and minimize surgical complications; however, given the improvements in endoscopic technology and risks associated with GA, alternate forms of anesthesia have been postulated. We aimed to evaluate the outcomes of URS under conscious sedation. Methods: We completed a retrospective cohort study from November 2019 to June 2020 at a tertiary-level hospital. All URSs that were performed under urologist-directed conscious sedation were included. Our primary outcome was the ability to complete URS, defined as success rate. Secondary outcomes included: stone-free rate, intraoperative complication rate, hospital admission rate, and sedation requirement. Univariate- and multivariate-adjusted logistic regression analyses were employed. Results: Ninety-nine URSs were included. Most (73/99, 73.7%) were performed for urolithiasis. The overall success rate was 83.8% (83/99), with 81.0% (34/42) intra-renal and 70.0% (16/23) proximal ureter success rates. The stone-free rate was 80.8% (59/73). No intraoperative complications nor hospital admissions were reported. The mean amount of sedation required was 3 mg (interquartile range [IQR] 2-4] of midazolam and 100 mu g (100-150) of fentanyl. On multivariate analysis, midazolam was significantly associated with increased success (odds ratio 2.496, 95% confidence interval 1.057-5.892, p=0.037). Conclusions: We have shown that proximal and intrarenal URS under conscious sedation is safe and effective. We were limited by our lack of followup, small sample size, selection bias to chose healthy patients, and lack of patient tolerability data. Patients and healthcare systems may benefit from implementing this innovation more broadly.