Dose-Dependent Efficacy of Nefopam for Preventing Catheter-Related Bladder Discomfort in Patients Undergoing Transurethral Ureteroscopic Lithotripsy: A Retrospective Case–Control Observational Study

Abstract

Background/Objectives: Catheter-related bladder discomfort (CRBD) is a common complication that patients with Foley catheters may experience following surgery. Previous studies have suggested that nefopam can reduce the incidence and severity of CRBD; however, dose-dependent effects (20 mg vs. 40 mg) have not been directly compared. Therefore, this study aimed to evaluate the dose-dependent effects of nefopam on CRBD, determine its effective dose, and assess the incidence of associated side effects. Methods: Electronic medical records of patients aged 18–70 years with American Society of Anesthesiologists physical status I–III who underwent elective transurethral ureteroscopic lithotripsy under general anesthesia from August 2016 to December 2022 were reviewed. Patients were categorized into three groups: premedication with intravenous nefopam 20 mg (group N20), premedication with nefopam 40 mg (group N40), or no premedication (control, group C). Results: The incidence rates of CRBD were 85.7% in group C, 81.3% in group N20, and 51.4% in group N40, showing a significant difference among the groups (p = 0.003, Pearson’s chi-squared test). Postoperative NRS was significantly different among the groups (p < 0.001, one-way ANOVA). In post hoc analysis, both group N20 and group N40 showed significantly lower scores compared to group C (p = 0.002, p = 0.001 respectively). The severity of CRBD also decreased in a dose-dependent manner, which was considered significant. No significant differences were observed among the groups in terms of intraoperative hemodynamic stability or postoperative nausea and vomiting. Conclusions: The administration of nefopam 40 mg significantly reduced the incidence and severity of CRBD compared with no premedication.