Single-incision short sling mesh insertion for stress urinary incontinence in women

5 Safety

This section describes safety outcomes from the published literature that the committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the interventional procedure overview.

5.1 Pain after the procedure was statistically significantly lower in the single-incision mini sling (SIMS) group (tension-free vaginal tape [TVT] 'Secur' trials excluded) than in the standard midurethral sling (SMUS) group (weighted means difference [WMD] −3.13; 95% confidence interval [CI] −4.89 to −1.36, n=4, I²=93%, p<0.0005), and groin pain was also statistically significantly lower (risk ratio [RR] 0.30; 95% CI 0.18 to 0.49, n=10, I²=19%, p<0.00001) in a systematic review and meta-analysis of 3,308 women from 26 randomised controlled trials (RCTs) comparing SIMS procedures (n=1,735) with SMUS (n=1,573) procedures in women with stress urinary incontinence.

5.2 Haemorrhage during the procedure was reported in 2% (2/120) of women in the SIMS group (including treatment with 'TVT Secur' slings) and in 1% (1/120) of women in the retropubic TVT (r‑TVT) group in a prospective comparative study of 240 women. In the same study, haemoglobin drop within 30 days of the procedure was reported in 1% (1/120) of women in the SIMS group and in none of the women in the r‑TVT group (p value not significant). Pelvic haematoma was reported in 1 woman in a prospective case series of 116 women treated by SIMS; it developed after revision surgery needed because of urinary outlet obstruction.

5.3 Vaginal tape erosion rates were not statistically significantly different between the SIMS group ('TVT Secur' trials excluded) and the SMUS group in the systematic review and meta-analysis of 3,308 women (RR 1.43; 95% CI 0.61 to 3.35, n=11, I²=0%, p=0.41). Vaginal mesh exposure rate was statistically significantly greater in the SIMS group ('TVT Secur' trials included) than in the transobturator sling (TOT) group in a Cochrane systematic review and meta-analysis of 3,290 women with stress urinary incontinence from 31 randomised or quasi-randomised trials (RR 2.59, 95% CI 1.21 to 5.56, n=9, I²=4%, p=0.015). In the same systematic review, bladder or urethral erosion rate was statistically significantly greater in the SIMS group ('TVT Secur' trials included) than in the TOT group (RR 17.79, 95% CI 1.06 to 298.88, n=2, I²=0%, p=0.046). Mesh extrusion was reported in 4% (4/113) of women in the prospective case series of 116 women with stress urinary incontinence treated with SIMS, within 12 months of the procedure. Three of the 4 mesh extrusions were treated by revision surgery that included trimming and excision; 1 mesh extrusion was asymptomatic and successfully treated with oestrogen cream. Erosion-free rates 5 years after the procedures were not statistically significantly different between the single-incision sling group and the transobturator vaginal tape group in a comparative study of 381 women (99% versus 96%, p=0.15).

5.4 Urethrovaginal fistula was reported in 1 women treated by SIMS in a single case report. The same patient had also bladder mesh erosion and vaginal mesh exposure. She was treated by excision of midurethral mesh, urethroplasty, Martius flap tissue transfer and cystourethroscopy but continued to have mild stress urinary incontinence.

5.5 De novo urgency or worsening of pre-existing surgery rates were not statistically significantly different between the SIMS group ('TVT Secur' trials excluded) and the SMUS group in the systematic review and meta-analysis of 3,308 women (RR 1.09; 95% CI 0.78 to 1.54, n=12, I²=0%, p=0.61). Rates of de novo overactive bladder symptoms 5 years after the procedure were statistically significantly higher in the single-incision sling group compared with the transobturator vaginal tape group in the comparative study of 381 women (9% versus 3%, p=0.012).

5.6 Repeat continence surgery rates were not statistically significantly different between the SIMS group ('TVT Secur' trials excluded) and the SMUS group in the systematic review and meta-analysis of 3,308 women (RR 2.00; 95% CI 0.93 to 4.31, n=10, I²=0%, p=0.08).

5.7 Lower urinary tract injury rates were not statistically significantly different between the SIMS group ('TVT Secur' trials excluded) and the SMUS group in the systematic review and meta-analysis of 3,308 women (RR 0.99; 95% CI 0.38 to 2.56, n=13, I²=0%, p=0.99). Bladder perforation was reported in 3% (3/120) of women in a prospective case series of 120 women. The patients were treated with a Foley catheter overnight, which was removed 1 day after the procedure.

5.8 Vaginal wall perforation was reported in 1% of women in the SIMS group, in 3% of women in the TVT group and in 4% of women in the TOT group in a retrospective comparative study of 531 women (relative number of women not reported).

5.9 Voiding difficulties after the procedure rates were not statistically significantly different between the SIMS group ('TVT Secur' trials excluded) and the SMUS group in the systematic review and meta-analysis of 3,308 women (RR 0.58; 95% CI 0.26 to 1.31, n=11, I²=31%, p=0.19).

5.10 Urinary tract infection within 30 days of the procedure was reported in 3% (3/120) of women in the SIMS group and in 4% (5/120) of women in the r‑TVT group in the prospective comparative study of 240 women (p value not statistically significant).

5.11 A bladder stone was reported in 1 woman 3 years after the procedure in a second case report. It was treated by excision of mesh transvaginally, separation of the stone from the eroded mucosal mesh and subsequent transurethral stone removal. The patient continued to have persistent stress urinary incontinence that had worsened after SIMS removal. She was subsequently treated with periurethral bulking and her symptoms of stress urinary incontinence improved.

5.12 Dyspareunia was reported in 1 woman in the prospective case series of 116 women, within 12 months of the procedure.

5.13 Delayed wound healing was reported in 1 woman in the prospective case series of 116 women, within 12 months of the procedure.

5.14 Anchor displacement was reported in 1 woman at the 1‑year follow-up visit in the RCT of 80 women (40 SIMS versus 40 TOT). The anchor was removed with the patient under local anaesthesia and the patient remained continent.

5.15 In addition to safety outcomes reported in the literature, specialist advisers are asked about anecdotal adverse events (events which they have heard about) and about theoretical adverse events (events which they think might possibly occur, even if they have never done so). For this procedure, specialist advisers did not list any new anecdotal adverse event. They considered that the following were theoretical adverse events: reaction to tape and poor anchoring of tape leading to failure in the short or long term.