Thirty-Day Incidence and Risk Factors for Lower Urinary Tract Fistula After Hysterectomy.

IMPORTANCE: Lower urinary tract (LUT) fistulas are rare but morbid complications after hysterectomy. Contemporary population-level data on incidence and risk factors are limited. OBJECTIVE: The objective of this study was to determine the incidence and risk factors for lower urinary tract fistulas within 30 days after hysterectomy using a national surgical database. STUDY DESIGN: This was a retrospective cohort study using hysterectomy-targeted files from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) from 2014 to 2020. Women undergoing hysterectomy who developed a LUT fistula were identified. The incidence of LUT fistula was determined. Univariate analysis assessed putative risk factors, and stepwise logistic regression identified independent predictors. RESULTS: Between 2014 and 2020, 226,398 hysterectomy cases were identified. The incidence of LUT fistula was 0.1% (n=222), including 106 ureterovaginal, 107 vesicovaginal, and 9 combined LUT fistulas. The mean age of patients who developed a LUT fistula was 48.6±10.6 years compared with 50.7±13.0 years for those who did not (P=0.005). Among patients who underwent hysterectomy for malignancy, the LUT fistula incidence was 0.14% (n=74). Wound classification and gynecologic malignancy were significant risk factors (P<0.001). Postoperative ureteral obstruction was strongly associated with LUT fistula development (P<0.001). Among fistula cases, 3.7% of patients (n=8) developed progressive renal insufficiency. Bleeding disorders, subspecialty type, immunosuppressive therapy, smoking, and dialysis were not associated with LUT fistula development. CONCLUSIONS: The incidence of LUT fistula after hysterectomy was lower than previously reported (0.1%-4%), likely because data were limited to 30 days postoperatively. LUT fistula rates decreased over the study period, which may reflect improvements in surgical technique and perioperative detection practices.