Surgical center size significant to reoperation risk after mid urethral sling

Patients who received mid-urethral slings (MUS) at higher-volume medical centers had a lower risk of reoperation, according to findings from a retrospective cohort study published in the Journal of Urology.¹

The results showed that at 9 years, there was a 55% reduction (HR, 0.45; P <.01) in reoperation risk for patients treated at higher-volume centers, defined as those performing more than 58 MUS per year. The reoperation rate at 9 years was 4.9% versus 9.8% at higher- versus lower-volume centers, respectively. Similarly, the reoperation rate at 9 years for recurrent stress urinary incontinence (SUI) was lower at higher-volume centers at 4% versus 9.1%, respectively (P <.01).

“Mid-urethral slings, the gold standard surgical treatment of SUI, are performed 250,000 times annually in the United States. As the population ages, it is estimated that these procedures will increase in utilization…Given that the goal of the MUS is to improve the quality of life of women with SUI, it is vital to understand modifiable risk factors that could reduce surgical morbidity and improve efficacy,” the study authors wrote.

From 2005 to 2016, 13,404 women received primary MUS at 11 centers. Each center had a range of 12 to 345 MUS performed each year with a mean surgical center volume of 128. Lower-volume centers (≤58 MUS/year) performed 7% of surgeries (999/13404, 17% of all reoperations) and higher-volume centers (>58 MUS/year) performed the other 93% (12,405/13,404) of the MUS.

The mean age of women in the study was 56.4 and 54.7 years for lower- and higher-volume centers, respectively. Most patients identified as Hispanic (55% and 52% in the lower- and higher-volume arms, respectively) or Caucasian (34% and 40%, respectively). The rest were Asian/Pacific Islander, African American, or other/unknown.

Beyond the primary outcome of MUS reoperation rate, secondary outcomes included specific reoperation rates for surgical failure and complications, excluding intraoperative complications. The researchers assessed the following types of reoperations: urinary retention, mesh exposure, pain, bleeding, infection, nerve injury, retropubic hematoma, bladder/urethral injury, and bowel injury.

“Our large managed care organization includes a diverse group of patients operated on at multiple surgical centers. We examined all MUS over greater than a decade of time. A wide range of MUS approaches and MUS synthetic mesh implants were used, representing typical practice patterns and enhancing generalizability. Implants were linked to patient electronic medical records thus enhancing internal validity,” the study authors wrote.

Patients operated on at higher-volume centers had a lower rate of repeat MUS at 1.8% versus 5.7% at lower-volume centers (P <.01). The rate of bulking injections was also lower at higher-volume centers at 0.8% versus 1.6%, respectively (P = .01). Reoperation for mesh exposure (0.2% vs 0.7%; P <.01) or infection (0% vs 0.2%; P <.01) also occurred less frequently at higher-volume centers.

Overall the rates of MUS mesh sling removal/revision were comparable between the higher- and lower-volume study arms. There was no difference between the 2 types of centers in terms of mesh removal/revision reoperation for urinary retention/urethrolysis, pain, or bleeding. There were no reported incidents of MUS mesh sling removal/revision for nerve injury, retropubic hematoma, bladder, urethral, or bowel injury in this study.

Given the results of their study, the authors have created specialized pelvic floor centers in their large managed care organization with higher-volume surgical centers. They believe this development, “will continue to improve surgical efficacy and safety” among patients suffering from SUI.

Reference

1. Berger A, Tan-Kim J, Menefee SA, et al. The Impact of Surgical Center Volume on Reoperation Risk after Mid Urethral Sling [published online ahead of print July 21, 2021]. The Journal of Urology. doi: 10.1097/JU0000000000002140