In contrast, when the definition of success includes incontinence of any type, the reported effectiveness is lower. For example, in the study that reported 60% effectiveness, success was defined as no incontinence symptoms of any type, a negative cough stress test, and no retreatment for stress incontinence or postoperative urinary retention.11
Retropubic slings, especially TVT, may be somewhat more effective for ISD,18-20 although this conclusion must be tempered by the small number of studies addressing the issue and differences in the diagnosis of ISD.21
Some studies have reported good success in treating mixed urinary incontinence with the retropubic and TOT slings,2,8 although other studies have reported that the initial benefit for urgency or urge incontinence is not sustained over time, compared with the benefit for stress incontinence.22 It is important to counsel patients before surgery that improvement in stress incontinence symptoms and general satisfaction is highly likely, but perfect bladder function is not.
Serious complications are uncommon
Complications are common after both retropubic and TOT slings, although serious complications are uncommon. Cystitis and temporary voiding difficulties are the most common problems after a sling procedure. If the patient is unable to void on the day of surgery, it is reasonable to discharge her with a Foley catheter in place for a few days or teach her to perform intermittent self-catheterization at home. In most cases, normal voiding will resume within a few days. Cystitis is at least partially related to the surgery itself and the duration of postoperative catheterization.
The frequency of some complications differs between the retropubic and TOT approaches to midurethral slings. For example, some literature suggests that irritative voiding symptoms such as urgency or voiding difficulty are somewhat less common after TOT slings, compared with retropubic slings. However, symptoms referable to the groin (pain and leg weakness or numbness) occur more commonly with the TOT approach.6
After placement of a TOT sling, 10% to 15% of women experience temporary inner thigh or groin pain or leg weakness and are usually managed conservatively with nonsteroidal anti-inflammatory drugs and physical therapy. Long-term or severe complications related to TOT sling passage are rare.
Major intraoperative complications are rare
The rate of these complications does not differ between retropubic and TOT approaches. Minor intraoperative complications—primarily, bladder perforation—occur more commonly with the retropubic approach.6
Bladder perforation with the TVT occurs in 4% to 7% of patients. However, the clinical significance of bladder perforation is minimal as long as the surgeon performs careful cystoscopy, recognizes bladder perforation, and repositions the trocar and mesh outside the bladder lumen. Bladder perforation caused by the trocar usually does not require specific treatment (except repositioning of the trocar outside the bladder lumen) and rarely results in later problems.
Mesh exposures occur with similar frequency for the different sling types as long as large-pore lightweight polypropylene is used. Dehiscence of the suburethral incision (mesh exposure) is uncommon with midurethral slings, occurring in 1% to 2% of patients. Dehiscence can be managed with estrogen cream or trimming of the exposed portion of the sling in the office. If symptoms or signs persist, removal of the exposed segment or the entire central portion of the sling, with closure of the vaginal epithelium, is indicated to allow for healing and resolution of symptoms. However, removal may lead to recurrence of the original SUI symptoms.
Retropubic hematomas occur in 1% to 2% of patients after placement of a retropubic sling, but major vascular injuries are rare—occurring in, perhaps, 3 in every 1,000 cases.
Bowel perforations are very rare but serious complications. A retropubic sling should be placed with caution or avoided in women who have a history of peritonitis, bowel surgery, ruptured appendix, or known extensive pelvic adhesions.
Major vascular injuries are also rare with TOT slings, occurring in approximately 1 to 2 cases in every 1,000.
Bladder injury occurs much less frequently after placement of a TOT sling, compared with the retropubic approach, although one study reported bladder injury in 2% of TOT cases.17 Although bladder injury is uncommon with the TOT approach, the morbidity associated with delayed detection of bladder injury is much higher than the morbidity associated with intraoperative detection and management. Therefore, we believe that cystoscopy should be performed in all TOT and retropubic sling procedures to either exclude bladder damage or detect and appropriately manage it.
For reassurance that intraoperative and postoperative blood loss is not excessive, it is reasonable to check one hemoglobin level before discharge, if desired.
How to individualize the choice of sling
Patients who have primary SUI: Retropubic or TOT sling. Objective and subjective success rates are similar, regardless of approach, and serious complications are infrequent. The retropubic approach has longer-term evidence of sustained benefit, compared with the newer TOT approach. We tend to treat younger patients with TVT and older patients with TOT. Surgeon experience and informed patient preferences may dictate the choice of sling (TABLE).