Approximately 4–15 % of women undergoing sling placement will report one or more UTIs [4]. Patients with typical symptoms of a UTI such as frequency, urgency, and/or hematuria should be evaluated with a urine culture. Those with severe, recurrent, or persistent symptoms may warrant a more thorough investigation including blood cultures, cross-sectional imaging, PVR , UDS, or cystoscopy when clinically appropriate. Abscesses, urinary obstruction, foreign bodies, sling perforation, or stones should all be included in the differential [10].

The AUA best practice policy statement on urologic surgery antimicrobial prophylaxis recommends 24 h of therapy for vaginal surgery [11]. However, a recent randomized controlled trial (RCT) of 149 patients by Jackson and colleagues evaluated the benefit of adding a 3-day antibiotic course postoperatively for patients undergoing vaginal surgery for SUI . Patients were randomized to a 3-day postoperative placebo (n = 75) or nitrofurantoin (100 mg two times a day) (n = 74). Overall, 37 (24.8 %) women were diagnosed with a UTI within the 6-week postoperative study period. The incidence was significantly lower in the treatment arm (17.6 %) compared to placebo (32 %), (p = 0.04) [12]. This may suggest a potential benefit to a short course of postoperative antibiotic prophylaxis but further studies are warranted. A recent study by Gehrich and colleagues used the National Surgical Quality Improvement Program (NSQIP) to review data collected on 9851 patients who underwent an MUS . Of these, 3.4 % developed a UTI , suggesting that the incidence of postoperative UTIs remains constant [13].

Lower urinary tract dysfunction or overactive bladder (OAB) can occur after placement of an MUS in patients without any previous OAB symptomatology. De novo urge incontinence or UUI is often transient and may resolve spontaneously. In such cases, patients should be counseled and reassured. However, persistent symptoms requiring intervention can occur in a quarter of patients [14]. The rate of de novo urge incontinence was previously estimated at 6 % [4]. In a series of 463 patients, Holgren and colleagues reported de novo urgency in 14.5 % of patients undergoing an MUS . Older age and parity were identified as significant risk factors for developing de novo urgency [15]. Lee and colleagues also evaluated risk factors for developing de novo urgency or UUI. The study identified 358 women with SUI or mixed urinary incontinence who underwent a MUS . De novo urgency occurred in 27.7 % of patients and de novo UUI occurred in 13.7 %. Intrinsic sphincteric deficiency, previous surgery for SUI or pelvic organ prolapse (POP), colposuspension, and/or preexisting detrusor overactivity increased the risk of postoperative urgency or UUI [16].

Reversible causes of de novo urgency/UUI should be evaluated and treated accordingly. A recent review by Abraham and Vasavada cited that de novo urgency occurs in 6 % of patients and modifiable causes include postoperative UTI (7.4–14.7 %), bladder outlet obstruction (BOO ) (1.9–19.7 %), and perforation of the urinary tract (0.5–5 %), with 0–28 % of cases occurring due to idiopathic etiologies [17]. Conversely, it has been also been proposed that a MUS can actually improve OAB symptoms. A study by Segal and coworkers retrospectively reviewed 98 MUS patients and found that approximately 57 % of patients with OAB demonstrated resolution of their symptoms, while only 4.3 % reported de novo OAB [18].

Treatment options for post-MUS urgency or UUI are similar to those for uncomplicated OAB and first include behavioral modification such as bladder training, bladder control strategies, pelvic floor muscle training, and/or fluid management. According to the updated AUA Guidelines for OAB, this may be combined with antimuscarinics or beta-3 agonists as options for second-line therapy, and onabotulinumtoxinA, sacral neuromodulation, or peripheral tibial nerve stimulation (PTNS) for refractory OAB [19]. Of note, a recent study by Serati and coworkers found that in the setting of de novo OAB after a MUS , solifenacin had significantly lower efficacy compared to controls [20]. OnabotulinumtoxinA, however, showed similar efficacy in a prospective study of 102 women comparing those with idiopathic OAB (n = 53) to women with de novo OAB post-MUS (n = 49) in a study by Miotla and colleagues [21].

Bladder outlet obstruction can present in a variety of ways and, as a result, the true incidence is difficult to accurately assess. The rate of urinary retention (catheter dependency for at least 28 days) is estimated to occur after 1–10 % of MUS [4, 22]. Additionally, patients may also complain of de novo frequency and urgency, UUI, hesitancy, straining to void, weak stream, incomplete emptying, dysuria, or recurrent UTIs. Pressure-flow UDS and a PVR may be used to assess BOO . Currently, however, there is no consistent index value for BOO in women and the absence of “high pressure, low flow” on UDS does not rule out iatrogenic obstruction [23, 24].

Treatment options for BOO vary widely according to individual patient factors, sling type, and patient or surgeon preference. Surgical intervention is often necessary including: sling loosening, sling incision, sling excision, or urethrolysis (infrapubic, retropubic, or transvaginal) [25]. Nonsurgical therapies may be offered for transient obstruction such as self-intermittent catheterization (SIC) or indwelling catheterization [22]. Often times, residual edema after the procedure can lead to urinary retention. Spontaneous voiding should occur within 1 week, and 66–100 % of temporary voiding dysfunction resolves by 6 weeks [14, 26].

If the patient cannot void at that time, loosening the sling has been reported in the literature. Advocates of this technique recommend making a small vaginal incision along the previous suture line. A right-angle clamp is then placed behind the sling and steady downward traction is applied to gently loosen the MUS [27]. Care must be taken to avoid urethral injury when passing the clamp between the overtensioned MUS and the periurethral fascia. This has been described in an office setting under a local anesthetic, but maximizing vaginal exposure in the operating room can be advantageous .

If the obstructing sling is well incorporated into the vaginal tissue, a sling incision can also be performed [28]. Once a vaginal incision is made over the previous suture line, the rough tissue overlying the MUS can typically be palpated. A cystoscope or urethral sound may be inserted into the urethra with upward traction to assist with identification of the MUS . The overlying granular tissue can be visualized or a tight, band-like structure can be identified. A right-angle clamp is then carefully inserted behind the sling and spread gently open (Fig. 16.2). Once the right-angle clamp is completely behind the sling, a scalpel is used to incise the MUS complex. This should be done with extreme caution to prevent urethral injury. The cut edges of the sling will then retract due to the tension release, and the suburethral portion of the sling may then also be excised to prevent erosion [10].

When the clinical presentation is especially delayed, a formal sling excision should be performed. This technique is best employed with an inverted, U-shaped anterior vaginal wall flap, with the base located at the bladder neck and the apex at the urethra. This incision maximizes exposure for the lateral dissection along the pubocervical fascia. If the MUS complex is identifiable at this juncture, the sling may be transected. The dissection is then carried as lateral as possible along the sling to safely remove the maximum amount of mesh (Fig. 16.3). This should be done judiciously as there can be significant bleeding and/or organ injury within the transobturator or retropubic spaces.

If the sling is not easily identifiable, the endopelvic fascia may be perforated with Metzenbaum scissors to enter the retropubic space. Using a combination of blunt and sharp dissection, the sling can often be identified laterally and then transected and excised. In such cases, a partial or total urethrolysis may also be required. With careful, blunt dissection, the urethra is freed from its attachments anteriorly to the pubic bone and proximally to the bladder neck (Fig. 16.4).

If adequate vesicourethral mobility cannot be achieved, a sling excision and urethrolysis can be performed from a retropubic approach [10]. This can allow for complete removal of the retropubic mesh arms. A low midline or Pfannenstiel incision is made, and the space of Retzius is adequately developed. Any retropubic and prevesical adhesions are sharply incised and all visible sling material is transected and removed (Fig. 16.5). Observation of free flowing urine by Crede maneuver can confirm a complete urethrolysis. In the original description, an omental pedicle flap is interposed between the urethra and the pubic bone to prevent readherence [10].

In the setting of a MUS , cure rates for urethrolysis are variable as much of the initial data are extrapolated from pubovaginal slings (Table 16.1). The earlier literature for suspension procedures and bladder neck slings suggests that the rate of recurrent SUI is low. However, a recent study of 107 MUS patients evaluated the rate of recurrent SUI after surgical intervention for BOO . In the 107 patients, recurrent SUI occurred in 49 %: significant bother was reported in 83 %, leading 14 % of the women to undergo a subsequent anti-incontinence procedure [44].