Abstract
Stress urinary incontinence (SUI) affects 4–10% of women per year with an estimated prevalence of up to 50% of adult women. Treatment options for SUI are predominantly procedural based, while invasive treatment options for patients with urge urinary incontinence are reserved for those who have failed conservative management or are intolerant of drug therapy. With the advent of the midurethral sling the types of complications seen after surgical treatment of SUI have changed. While intraoperative complications such as the incidence of bladder trocar injuries are well cited, the incidence of late complications such as iatrogenic bladder outlet obstruction and vaginal mesh exposure or urinary tract erosion may be underreported secondary to difficult or subtle diagnosis and/or lack of long-term studies reporting on these complications. This chapter is a resource for clinicians on the incidence, prevention, recognition, and management of complications associated with the surgical treatment of female urinary incontinence.
Keywords
Complications of female urinary incontinence surgery, Stress urinary incontinence, Midurethral sling, Transvaginal mesh exposure, Voiding dysfunction, Bladder outlet obstruction
Key Points
- 1.
The popularity of midurethral polypropylene slings has changed the types of complications commonly seen in surgical treatment of stress urinary incontinence (SUI).
- 2.
Intraoperative trocar injury to the bladder during midurethral sling placement is not uncommon, and replacement of the trocar can be accomplished with minimal morbidity.
- 3.
Currently, few or no data on overall complications support one choice of midurethral slings over another (i.e., retropubic vs transobturator) as causing less morbidity; however, some of the complications reported with each of these procedures are unique to that approach.
- 4.
In comparing midurethral slings, obstructive complications are more common with retropubic slings while neuromuscular complications are more likely in the transobturator approach.
- 5.
New voiding symptoms including overactive bladder symptoms or recurrent urinary tract infections (UTIs) following SUI surgical procedures may indicate iatrogenic bladder outlet obstruction (BOO), which is a very difficult and subtle diagnosis in many patients.
- 6.
Attention to technique, experience of the surgeon, and careful endoscopic examination of the urinary tract following anti-UI surgical procedures are important factors in reducing perioperative and postoperative complications.
- 7.
Intradetrusor botulinum toxin injections and sacral neuromodulation have become the mainstay for treatment of refractory overactive bladder and urgency urinary incontinence.
Stress urinary incontinence (SUI) affects 4–10% of women per year with an estimated prevalence of up to 50% of adult women. Urinary incontinence (UI) is defined as the complaint of involuntary leakage of urine. Patients with UI may have numerous related problems including depression as a result of the perceived lack of self-control, loss of independence, and lack of self-esteem, and they often curtail their activities for fear of an “accident.” UI and related overactive bladder may also have serious medical and economic ramifications for untreated or undertreated patients, including perineal dermatitis, worsening of pressure ulcers, urinary tract infections (UTIs), and falls. For these reasons, many individuals suffering from this condition seek treatment. Surgery plays a major role in the therapy of some types of UI. Surgical procedures for UI are some of the most commonly performed operations in the United States by urologists. Thus, understanding how to avoid, and when necessary how to treat, complications related to these surgical procedures is important.
Types of Incontinence
Simply stated, UI may result from abnormalities of the urethra (including the bladder outlet and urinary sphincter), or the bladder, or may be caused by a combination of abnormalities of both structures ( Table 49.1 ). Abnormalities may result in underactivity or overactivity of the urethra or bladder with the subsequent development of UI.
| Abnormality | Type of Clinical Incontinence |
|---|---|
| Bladder overactivity | Urge |
| Bladder underactivity | Overflow |
| Urethra overactivity | Overflow |
| Urethra underactivity | Stress |
Urethral underactivity results in stress UI (SUI). Urodynamic SUI is the involuntary leakage of urine associated with an increase in intraabdominal pressure in the absence of a detrusor contraction.
Surgical correction of female SUI is directed toward either of the following: (1) repositioning the urethra or creating a backboard of support or otherwise stabilizing the urethra and bladder neck in a well-supported retropubic position that is receptive to changes in intraabdominal pressure (i.e., sling), or (2) creating coaptation or compression or otherwise augmenting the urethral closure forces provided by the intrinsic sphincteric unit (i.e., periurethral injectables) that affect urethral and bladder neck support.
Urgency UI is the involuntary leakage of urine associated with the symptom of urgency, defined as a sudden compelling desire to void that is difficult to defer. This disorder is generally attributed to detrusor overactivity, as shown by urodynamic assessment. Both phasic bladder overactivity (involuntary bladder contractions) and tonic overactivity (decreased compliance) can contribute to UI. Careful urodynamic evaluation may be necessary in these patients to ascertain lower urinary tract physiology, to assess the risk of deterioration to the upper urinary tract, and to search for coexisting urethral or sphincteric UI.
Most of these patients are treated with a combination of behavioral modification, pelvic floor physical therapy, and oral pharmacologic agents. However, for patients with refractory conditions, the goal of surgical intervention is either to reduce or abolish bladder overactivity and the sensation of urgency or to provide a reservoir of adequate size for the low-pressure storage of adequate volumes of urine.
Types of Incontinence Operations
Except in unusual circumstances, the surgical repair of UI is elective. The decision to treat symptomatic UI surgically should be based primarily on the premise that the degree of bother or lifestyle compromise to the patient is sufficient to warrant an elective operation and that nonoperative therapy is either undesired or has been ineffective. Therefore, it is particularly troublesome to both the surgeon and the patient when complications arise during or after performance of these elective procedures. In some instances, these complications may be life threatening or may considerably worsen symptoms or quality of life. Thus, the surgeon should clearly describe and counsel patients regarding potential complications preoperatively. Fortunately, however, complications of the surgical treatment of UI are uncommon and when they occur are often amenable to treatment.
Stress Incontinence Operations
The goal of surgical treatment of SUI is to augment urethral closure forces to prevent the egress of urine from the urethra during periods of increased abdominal pressure while at the same time preserving voluntary, low-pressure, and complete bladder emptying. This treatment may involve the use of retropubic or transvaginal suburethral support or compression (slings), periurethral injection (e.g., collagen), or circumferential compression (artificial genitourinary sphincter) ( Table 49.2 ). The precise manner in which each operative procedure improves urethral closure forces and thereby restores urinary continence is not well understood. Nonetheless, >100 different operations have been designed to treat female SUI.
| Surgical Option | Goal |
|---|---|
| Anterior repair | Repositioned urethra or “plicated” sphincter |
| Retropubic approach | Repositioned or stabilized urethra or creation of a “backboard” of support for urethral compression during increased intraabdominal pressure |
| Marshall-Marchetti-Krantz vesicourethropexy | |
| Burch colposuspension | |
| Vaginal needle suspension | Same as retropubic approach with avoidance of a large abdominal incision and associated morbidity |
| Stamey | |
| Raz | |
| Sling | |
| Autologous, cadaveric, synthetic, vaginal wall, etc. Tension-free vaginal tape and other polypropylene midurethral slings | Same as retropubic approach with or without direct urethral coaptation or compression |
| Dynamic midurethral support | |
| Artificial urinary sphincter | Intermittent, dynamic urethral coaptation and compression |
| Bulk agents (injectables) | Improved urethral coaptation |
For many years, the transabdominal approach to vesicourethropexy including procedures such as the Marshall-Marchetti-Krantz (MMK) vesicourethropexy and the Burch colposuspension were very popular interventions for female SUI. The goal of these procedures is to elevate or, in some cases, simply prevent rotational descent of the urethra and bladder neck by securing the paraurethral or paravesical fascia to a fixed retropubic structure. Additionally, these procedures may also provide a stable “backboard” on which the urethra and bladder neck are compressed during increases in intraabdominal pressure.
The transvaginal or “needle” suspension procedures were proposed as alternatives to the retropubic operations for urethral UI resulting from vesicourethral hypermobility. These techniques have largely fallen out of favor, especially following a comprehensive meta-analysis published in 1997 suggesting that these procedures were less durable in the long term as compared with slings and retropubic suspensions. A subsequent American Urological Association (AUA) guideline document did not even include these procedures in the update as there were no new publications on their utilization. Therefore such procedures will not be further discussed in this chapter.
Bone-anchoring techniques emerged as an alternative method of suture fixation for both transvaginal needle suspensions and some types of slings in the 1990s. Numerous proprietary fixation systems had been developed including transvaginal and suprapubic delivery bone-anchoring systems, all of which deliver a suture secured to a metallic screw into the cortical bone of the pubic rami on either side of the midline. The initial enthusiasm for these adjunctive procedures was somewhat dampened by the lack of a demonstrable long-term durable benefit over other techniques as well as the cost and potential associated morbidity, including osteomyelitis and osteitis pubis. Bone-anchoring techniques have largely fallen out of favor.
Pubovaginal sling surgery was originally described more than 100 years ago. Fascial slings are generally placed at the level of the bladder neck and proximal third of the urethra and use either autologous tissue harvested from the patient intraoperatively (e.g., anterior rectus sheath, fascia lata) or xenograft or allograft fascia. The fascia may be full length (extending from the abdominal wall through the retropubic space, under the urethra, and back up to the abdominal wall) or rectangular (extending into the retropubic space on either side but secured to the anterior abdominal wall with sutures attached to either end of the sling) ( Fig. 49.1 ).
The midurethral polypropylene sling (MUS) has become the most common type of sling procedure performed in the United States. This popularity is likely the result of the low morbidity, technical ease, and speed of the procedure; its long-term durability and safety; and the rapid recovery and convalescence. These slings, of which many proprietary types are available, are similar in the completely tension-free, minimally invasive technique in which they are placed under the midurethra. Depending on the choice of device, these slings may be placed through a transvaginal incision utilizing either a suprapubic or transobturator approach. US Food and Drug Administration (FDA) notifications regarding transvaginal mesh placement surfaced in 2008 and 2011. In October 2008, the FDA issued a Public Health Notification regarding the use of transvaginal mesh for pelvic organ prolapse (POP) and SUI, and in July 2011, the FDA released a Safety Communication on serious complications associated with transvaginal mesh for POP but not SUI. The implications of these FDA statements were quite broad including medico-legal ramifications and ongoing nationwide litigation. As the FDA continues its literature review of transvaginal mesh for the treatment of SUI it has reiterated that the standard polypropylene mesh MUS is safe and effective in the treatment of SUI. Despite the FDA statements, it is important to recognize that there has not been a mandatory FDA recall of any transvaginal mesh product. As a result of many converging and complex factors, several mesh manufacturers have voluntarily withdrawn some or all of their POP and/or SUI mesh products but this was not due to a product recall by the FDA.
Periurethral injectable agents have been used for the treatment of SUI in women for decades. Most periurethral agents are injected in a retrograde fashion under direct cystoscopic guidance as an office-based procedure. The exact means by which periurethral injectable agents exert their favorable effects on continence has not been well defined, although an obstructive mechanism or an improved “seal” effect has been suggested. Furthermore, the eventual mechanism of failure for most of these agents is not well understood, although it is believed that biologic reabsorption, particle migration, and ongoing degeneration of the sphincteric apparatus may be contributing factors. Generally, these agents are safe and have good initial efficacy but lack long-term durability.
The artificial urinary sphincter is used in some centers as primary therapy for female SUI. However, in the United States, this device is only very infrequently used in female patients.
Urge Incontinence Operations
Sacral neuromodulation, intradetrusor injection of botulinum toxin, and augmentation enterocystoplasty have been used for individuals undergoing surgical treatment of urgency UI. Sacral neuromodulation has been used since the 1980s but was finally approved by the FDA for use in the United States in 1997 as a therapy for urinary frequency, urgency, and urge UI. A staged implantation technique or an office-based peripheral nerve evaluation is the initial step in sacral neuromodulation. In either case a good response leads to implantation of a permanent implantable pulse generator and neurostimulator lead electrode. Low-frequency stimulation of the S3 nerve root results in modulation of neural activity in the lower urinary tract and pelvic floor. The exact mechanism by which sacral neuromodulation exerts its therapeutic effects remains unclear.
In 2011 the FDA approved intradetrusor injection of botulinum toxin A (BT) for the treatment of refractory neurogenic detrusor overactivity, and in 2013 the FDA approved its use for refractory idiopathic detrusor overactivity. BT is produced by the bacterium Clostridium botulinum and is the most potent biologic neurotoxin known. The current approved dose for idiopathic detrusor overactivity is 100 units, and for neurogenic detrusor overactivity the approved dose is 200 units. The toxin is injected into the detrusor muscle through the cystoscope with a long, fine needle in a series of 20–30 injections. This treatment is most commonly performed using local anesthesia as an office-based procedure.
BT is thought to produce its efferent motor paralytic effects by inhibiting acetylcholine release at the presynaptic cholinergic neuromuscular junction by cleaving SNAP-25, an intracytoplasmic protein, which blocks the binding and fusion of the synaptic vesicles to the presynaptic membrane terminal. This prevents release of acetylcholine as well as a variety of other neurotransmitters and neuropeptides into the synapse. Clinically this results in muscle weakness, diminished contractility, and muscle atrophy at affected sites some 3–14 days following injection. The effect is reversible in 3 to 12 months, but the mechanism by which smooth muscle regains contractility over time is not well understood and is not fully explained by axonal sprouting. The mechanism of action of BT in reducing urinary urgency may also involve modulating some aspects of the afferent limb of the micturition reflex as well.
Although there is sparse literature available, it appears that augmentation enterocystoplasty as a treatment for urgency incontinence has become less utilized with the increasing widespread use of BT and neuromodulation. Further discussion and complications related to the use of intestine in the urinary tract are reviewed elsewhere in this textbook and are not considered further here (see Chapter 48 ).
Prevention of Complications
Although most complications related to the surgical treatment of female UI are treatable and generally reversible, the optimal situation is to prevent or minimize the potential for an adverse outcome. This process begins in the preoperative period and is initiated during the diagnostic evaluation and workup. Many factors should be considered in determining the optimal surgical therapy for the patient with UI. These include the origin and type of UI, bladder capacity, renal function, sexual function, medical comorbidities, severity of the leakage, the presence of associated conditions such as vaginal prolapse or concurrent abdominal or pelvic disease requiring surgical correction, prior abdominal and pelvic surgical procedures, and finally the patient’s suitability for and willingness to accept the risks of surgery. All these factors may affect both the choice of surgical treatment and the risk of surgical complications.
The proper choice of candidate for an anti-UI operation cannot be overemphasized. One study found the most common reason cited for failure of the previous operation was poor surgical technique, and the next most common reason was the wrong surgical indication. Both of these factors certainly can be addressed and minimized preoperatively. The diagnosis of SUI must be firmly established to propose outlet-enhancing surgery for the treatment of SUI. Other diagnoses that may mimic SUI should be definitively eliminated including fistula, ureteral ectopy, bladder calculi, urethral diverticula, and overflow UI. Overflow UI, in particular secondary to a neurogenic or myogenic disorder, can be mistaken for SUI and this misdiagnosis can lead to inappropriate intervention and surgical treatment failure. The patient’s history should be consistent with and confirmed by findings on physical examination and, when appropriate, radiographic or urodynamic testing.
Reversible factors should be addressed. For patients with postmenopausal, hypoestrogenic vaginal atrophy, topical estrogen replacement may reduce the incidence of postoperative vaginal wound dehiscence or extrusion of sling material. UTI and genital tract infection (e.g., candidiasis) should also be treated before surgical intervention. Nutritional disorders should be assessed and corrected preoperatively before elective surgical treatment is performed. Finally, treatment of any medical comorbidities (e.g., diabetic control, hypertension) should be optimized.
Another preoperative factor associated with risk of complications is operative experience with a given procedure. The “learning curve” for “simple” procedures such as midurethral slings should not be underestimated and the number of cases performed may correlate with risk of complications.
Complications
The field of SUI surgery has advanced rapidly. As noted previously, the types of procedures performed have evolved from transvaginal needle suspensions and retropubic suspensions to various types of slings, most commonly the midurethral polypropylene slings. This shift has implications for the types of complications seen in contemporary practice as compared with complications seen even a few short years ago. Therefore the majority of the discussion that follows concerns the midurethral slings.
Choice of Approach
The relative risks of each complication among various types of surgical procedure, especially within a single category such as midurethral slings, are impossible to determine because of the limited amount of randomized controlled trials comparing procedures and approaches. Currently, no published literature provides sufficient evidence to recommend one procedure or approach absolutely over another based only on complication rates. However, it is important to recognize that some types of complications are unique or more likely to occur with one procedure as compared to another. For example, in a randomized controlled trial (RCT), Albo and colleagues compared Burch colposuspension with pubovaginal sling and in this trial the investigators found that the risks of urinary tract infections, voiding dysfunction, and postoperative urge incontinence were greater in the women who underwent sling procedure but the risk of incidental cystotomy was greater in the Burch group. Comparing results within a single category, the 2010 TOMUS RCT compared the outcomes of retropubic and transobturator midurethral slings. There was a higher rate of voiding dysfunction requiring surgery in the retropubic group, but neurologic symptoms were greater in the transobturator group. These findings have been confirmed by several additional studies and documented in a 2015 Cochrane review on midurethral slings.
Risk Factors
Identifying preoperative risk factors such as age, obesity, prior surgical treatment, and impaired contractility that consistently predict for intraoperative and postoperative complications has also been difficult. Most of the data available in the literature are from retrospective studies. In regard to vaginal mesh exposure, one study of 1439 women found that older age, diabetes mellitus, smoking, vaginal incision >2 cm, and recurrent vaginal incisions increase the risk of vaginal mesh exposure. Some investigators have found that prior surgical treatment is a predictor of intraoperative bladder injury. This may be related to the type of prior SUI surgical treatment: Prior retropubic procedures such as Burch or MMK may lead to retropubic scarring and a risk of bladder injury, whereas a prior transvaginal operation such as a Kelly plication, in which the retropubic space is not violated, may not. While there is no standard to evaluate and ascertain which patients will have postoperative voiding dysfunction, it is reasonable to speculate that women with preoperative voiding dysfunction (emptying phase dysfunction) will have a higher risk of postoperative voiding dysfunction and urinary retention.
Complications Related to Stress Urinary Incontinence Surgery
Intraoperative Complications
Bleeding.
The risk of blood loss greater than 200 mL during SUI surgery is small. The incidence ranges from 0.22% to 8%, with autologous fascial sling associated with the greatest risk and transobturator midurethral sling associated with the least risk of substantial bleeding. The risk of blood transfusion ranges from 0.6% to 9% with a reported risk of only 0.6–2% in midurethral slings and 7–9% in Burch suspensions.
The risk of bleeding during surgical treatment of SUI can be minimized, but not entirely eliminated, by good operative technique. Multiple blood vessels traverse the deep pelvis including large venous channels in the retropubic space. Named vessels in the obturator fossa, along the pelvic sidewall including the iliac vessels, and within the vascular pedicle of the bladder are at risk for injury, especially during vaginal surgical treatment of UI, because of the lack of direct visualization of these structures during passage of trocars or needles. Major vascular injury can quickly lead to life-threatening hemorrhage if it is not recognized intraoperatively and may result in large retropubic hematomas postoperatively.
Bleeding during retropubic bladder neck suspension is usually easily visualized and controlled with a combination of cautery, suture ligature, and, if necessary, direct compression. Occasionally, sponge sticks and readjustment of the retractors may be needed to visualize the bleeding vessels optimally. The retropubic anatomy is very familiar to most urologic surgeons, and bleeding during these procedures is rarely problematic.
In contrast to bleeding during retropubic surgical procedures, bleeding during transvaginal operations can be more problematic at times and more difficult to control. The initial dissection of the vaginal wall from the underlying fascia should be associated with minimal bleeding. Bleeding encountered during this early dissection may indicate an excessively deep and incorrect surgical plane within the wall of the bladder or urethra. In this circumstance, immediate recognition and reevaluation are necessary to avoid inadvertent entry into the urinary tract and to minimize bleeding. Following identification of this situation, dissection should then proceed in the proper surgical plane, which, in reoperative surgical procedures, may be difficult to identify.
Another common site of bleeding during transvaginal SUI surgical procedures occurs when the endopelvic fascia is traversed. Entry into the retropubic space from the transvaginal side or placement of the suprapubic needles or trocars from the abdominal side may be associated with copious bleeding as the endopelvic fascia is perforated. Again, knowledge of the anatomic features, careful attention to technique, maintenance of countertraction, and proper positioning of the perforating scissors (with the tips curved away from the bladder) or trocar in three planes minimize most bleeding ( Fig. 49.2 ). An initial gush of venous bleeding is not unusual during this maneuver, and, although it may be unsettling to the operating surgeon, the bleeding dissipates quickly without further manipulation.
If the bleeding continues and is brisk, the vagina can be packed. It can be very helpful to elevate the anterior vaginal wall manually and compress it anteriorly directly against the posterior symphysis pubis for several minutes using the surgeon’s hand, a sponge stick, or a retractor. These maneuvers effectively tamponade bleeding in the retropubic space. It is not advisable to “chase” this bleeding using a transvaginal approach. Only very rarely is the exact bleeding point identified and controlled in this manner.
Transvaginal exploration for bleeding results in ongoing blood loss as the surgeon struggles with relatively poor exposure and visualization. Packing and compression lead to adequate control in most cases, and if not the surgeon should expeditiously complete the procedure, close the incisions, and pack the vagina. Occasionally, in addition to vaginal packing, a Foley catheter inserted through the urethra with the balloon overinflated and then placed on traction adds additional security. Brisk bleeding that does not respond to manual compression for an extended period may suggest a major vessel injury and mandates retropubic exploration or consideration of angioembolization in interventional radiology.
Urinary Tract Injury
During surgical procedures for SUI, the urethra, bladder, or much more rarely the ureters may be injured. The key to the management of each of these injuries is immediate recognition and repair. Long-term sequelae resulting from unrecognized urinary tract injury can be devastating to the patient and can have potentially substantial medico-legal implications for the physician.
Urethral Injury.
From the transvaginal side, injury to the urethra may occur during initial dissection of the vaginal wall off the underlying fascia. As noted earlier, excessively deep dissection, especially in reoperative surgical procedures, risks urethral injury. This injury is usually, although not invariably, heralded by an unexpected amount of bleeding. Placement of a urethral catheter before incision will help to identify the urethra intraoperatively and in the case of urethral injury will allow immediate recognition as the catheter becomes visible in the operative field.
If a urethral injury is suspected, urethroscopy may be performed. The urethra should be repaired immediately and closed primarily in two layers by using absorbable sutures in a watertight fashion. The urethra can be repaired over a ≥14Fr catheter. It is not necessary to leave a drain other than the urethral catheter. The integrity of the repair can be tested by injecting saline through a syringe attached to an angiocatheter (intravenous [IV]) sheath into the urethral meatus adjacent to the catheter with the balloon snugged up against the bladder neck. Failure to recognize the injury or failure to repair it properly risks urethrovaginal fistula.
The urethra may also be injured during trocar placement in midurethral sling procedures, needle placement for transvaginal suspensions, or cystocele repair. Countertraction during the initial dissection, maintenance of adequate exposure, and a working knowledge of the anatomy are helpful in avoiding urethral injury.
The incidence of urethral perforation during midurethral sling placement is low, ranging from 0.2% to 2.7%; however, in the event of a concomitant urethral injury during a planned synthetic sling, it is advisable to repair the urethra and abort the sling procedure until the urethra is completely healed. An autologous sling is considered a safer alternative than a synthetic sling in the setting of a urethral injury as a SUI procedure, but there are few if any data supporting this notion.
The urethra is rarely injured during retropubic surgical procedures because the middle and distal thirds are protected by the symphysis pubis.
Bladder Injury.
Intraoperative bladder injury may occur during transabdominal and transvaginal SUI surgical procedures. The potential for urinary tract injury varies considerably with the experience of the surgeon, as well as with the operative approach. Several studies have reported a bladder perforation rate of 1–8% during passage of needles or trocars for placement of pubovaginal or midurethral slings. Most literature documents a higher risk of bladder injury with the retropubic approach (3–6%) as compared with the transobturator approach (0.4–0.7%) during midurethral sling operations. Repeat surgical procedures are almost certainly associated with a higher risk of urinary tract injury in patients undergoing midurethral sling operations.
Injury to the bladder during midurethral sling procedures is diagnosed intraoperatively by careful endoscopic examination of the bladder and bladder neck with a flexible cystoscope including retroflexion and examination of the bladder outlet region, or a rigid cystoscope using a 70-degree lens. Inspection is performed with a completely full bladder following passage of the trocars but before deployment of the midurethral sling. The bladder should be filled and then examined to ensure that a small injury does not go unrecognized in a fold of the bladder wall. To avoid injury during trocar needle passage, the urethra should be clearly palpated, the bladder drained, and the pelvic anatomy well delineated. If a bladder injury is noted intraoperatively, the trocar should be removed and reinserted after draining the bladder. The bladder is then reinspected to assure that the re-passing of the trocars was successful.
Bladder injury from a trocar usually does not require primary closure and when addressed intraoperatively has not been shown to have long-term adverse sequelae. Postoperative Foley catheter drainage of the bladder after trocar cystotomy has not been extensively studied, and there are a paucity of published data evaluating the need for prolonged catheterization. In a retrospective review of 30 patients experiencing trocar cystotomy at the time of suprapubic midurethral sling placement, Crosby et al. found that 80% passed a voiding trial the day of surgery and were discharged home without a catheter. The 20% who failed a voiding trial were sent home with a Foley catheter and successfully voided within 4 days. At 6-week follow-up, no patient experienced voiding dysfunction or irritative bladder symptoms and no patient required additional intervention. Although not mandatory, prolonged catheterization may be desired in patients with a larger cystotomy to avoid urinoma, fistula formation, and pelvic abscess. Also, catheterization and continuous bladder irrigation may be required if there is significant gross hematuria after cystotomy.
During a transvaginal pubovaginal sling procedure or during performance of urethrolysis, it is common to perforate the endopelvic fascia intentionally to gain entry to the retropubic space. This perforation maneuver is often done sharply with curved scissors. The surgeon must be aware of lower urinary tract anatomy during this maneuver to avoid injury. Countertraction on the pelvic fascia away from the side of interest as the scissor perforates into the retropubic space will help to avoid injury. If injury occurs, lower urinary tract perforation in this setting is often larger than that seen with the passage of the trocars during a midurethral sling. The injury should be isolated and closed in two layers. A suprapubic drain can be placed and the lower urinary tract drained for several days to ensure healing. In addition, ureteral patency should be assessed in this setting because the injury can track proximally on the trigone.
Injury to the bladder during retropubic operations is usually confined to the anterior bladder wall. This complication is usually easily recognized and repaired. Postoperative Foley catheter drainage is mandatory. During a Burch or MMK procedure, a stitch may be inadvertently placed transmurally into the bladder or urethral lumen. Intraoperative cystoscopic examination identifies these injuries and permits removal and replacement of the suture.
Ureteral Injury.
Ureteral injury during surgical treatment of UI is uncommon. The reported incidence of ureteral injury for all incontinence procedures is 0.18–4%. With the advent of midurethral slings, these injuries are becoming more rare (0.18–1.22%) given the expected location of the sling at the level of the midurethra. However, the ureter may be kinked or obstructed during Burch or MMK procedures or during vaginal prolapse repair. Virtually all these injuries can be identified by intraoperative cystoscopy. The administration of IV vital dyes such as indigo carmine permits obvious visualization of ureteral efflux that confirms ureteral patency. Suspected ureteral injuries are confirmed by retrograde pyeloureterography. Most of these injuries are related to suture placement. When found, ureteral injuries may be treated by removal of the offending suture and placement of a temporary indwelling ureteral stent. Ureteral transection requires ureteroneocystostomy.
Intraoperative Cystoscopy.
Cystoscopy is a low-morbidity procedure that requires little additional time, effort, or resources. However, some additional expense is incurred in performing cystoscopy, and the practitioner requires advanced training in endoscopic examination of the lower urinary tract. Nevertheless, careful cystoscopic examination of the lower urinary tract following SUI surgical procedures enables the surgeon to evaluate the patient for almost all lower urinary tract injuries. If IV vital dye is given, ureteral injury can also be excluded by visualizing efflux from the ureters. In the most recent AUA Guideline on Surgical Management of Female Stress Urinary Incontinence, intraoperative cystourethroscopy is a treatment standard in all patients undergoing a sling procedure. The bladder must be examined when it is full, and careful attention should be paid at the 2- and 10-o’clock positions at the bladder neck and just inside the bladder neck because these are the locations of a majority of lower urinary tract injuries during SUI surgical procedures.
Inexperience with cystoscopy leads to a high rate of missed intraoperative perforations. If perforations are recognized intraoperatively, the lower urinary tract can be quickly repaired and drained if necessary. Unrecognized urinary tract injuries can lead to infection, sepsis, fistula, stones, and other complications. Transobturator slings can be associated with injury to the lower urinary tract 0.4–0.7% of the time, and thus intraoperative cystoscopy should be performed in these cases as well.
Bowel Injury.
Multiple reports of bowel injury during surgical procedures for SUI have been reported. Fortunately this complication is rare. Bowel injury may occur during retropubic dissection for a Burch or MMK procedure, on entry into the retropubic space during an autologous pubovaginal sling or urethrolysis, or during passage of needle passers or trocars during midurethral sling procedures. These injuries can be devastating complications leading to sepsis, abscess, and even death. Unfortunately, most of these injuries are not recognized until the postoperative period, when they lead to considerable morbidity. Initial signs and symptoms heralding a bowel injury may be subtle, including low-grade fever, abdominal pain, and ileus. If bowel injury is suspected, a diagnostic evaluation including plain and upright abdominal radiographs to ascertain the presence of intraabdominal free air and cross-sectional imaging should be pursued expeditiously. Laparotomy, repair of the bowel injury, and, possibly, bowel resection are necessary for definitive treatment. In some cases, temporary proximal bowel diversion may be necessary.
Postoperative Complications
Voiding Dysfunction and Urinary Retention.
Bladder outlet obstruction (BOO) may occur following SUI surgical procedures. This complication manifests as prolonged complete urinary retention, persistently elevated post-void residual urine volume, or as variably bothersome and poorly categorized lower urinary tract symptoms including combinations of obstructive symptoms and urinary urgency or UI and recurrent urinary tract infection. These last two groups are difficult to identify and are often not recognized as having BOO by many investigators. The incidence of postoperative voiding problems across various procedures is variable and difficult to compare. A meta-analysis published in 2014 found urinary retention rates <6 weeks postoperatively to be higher in Burch suspension (17%) followed by pubovaginal slings (12%), and that number was reduced to 7.6% and 7.5%, respectively, at >6 weeks, while midurethral slings had a retention rate of 2.3–3.1% in both groups. While the incidence of retention was higher in Burch suspension, the need for intervention was zero. Meanwhile, midurethral slings require intervention for retention or voiding dysfunction in 1–3% of women. The incidence of voiding dysfunction, including urinary retention (16.6%) and de novo urgency and urge UI following midurethral sling procedures ranges from approximately 2% to 25%. In the TOMUS multicenter prospective study, transobturator slings had fewer “obstructive” complications than did retropubic midurethral slings. This has been verified by additional studies and summarized in the 2015 Cochrane review of midurethral slings. The minimally invasive midurethral sling procedures are mechanistically tension free, and as such it is not surprising that they likely result in an overall lower incidence of postoperative voiding dysfunction than that seen with other types of open SUI procedures.
The finding of absolute prolonged urinary retention makes the diagnosis of obstruction fairly straightforward if the patient had relatively normal voiding dynamics preoperatively. One potential exception is the patient who voids primarily by pelvic floor relaxation. Female patients may void without a perceptible increase in intravesical pressure, and in these individuals, even a modest increase in outlet closure forces, such as that caused by a sling, may result in urinary retention. In many other patients, the diagnosis of BOO is extremely difficult. Urodynamic studies, especially video urodynamic studies, are often pursued diagnostically but may not be helpful in many cases because the classic “high pressure–low flow” pattern may not be present. Nitti and colleagues have suggested that the radiographic finding of a discrete area of narrowing in the urethra in combination with dilation of the proximal urethra is highly suggestive and potentially diagnostic of female BOO. However, in spite of this, no pressure-flow urodynamic criteria accurately predict successful voiding following urethrolysis.
Various nomograms have been developed for the diagnosis of female BOO but none is absolutely accepted as the gold standard. For patients not in frank urinary retention, the diagnosis of BOO is strongly suggested by the postoperative onset of irritative voiding symptoms, recurrent UTIs, and a poor urine stream. Physical examination may be completely normal or suggest an oversuspended midvaginal segment (“swan neck deformity”) or the lack of mobility of the urethra following insertion of a metal sound. De novo prolapse should be excluded as a cause of postoperative BOO. An unrecognized and thus unrepaired cystocele may result in BOO following SUI surgical procedures.
Before surgical intervention for postoperative urinary retention is considered, many transient causes should be considered. These are potentially unrelated to iatrogenic BOO and the mechanical effects of the procedure. In the immediate postoperative period, pain is a common reason for delayed micturition. Similarly, postoperative pain relief from narcotic analgesics may suppress micturition as well. These effects are temporary and a period of catheterization for several days postoperatively allows resumption of normal voiding in most cases. Other potential causes of temporary postoperative urinary retention include patient immobility, edema at the operative site, and retropubic hematomas.
Management options for prolonged voiding difficulties include repeated voiding trials, initiation of intermittent urethral catheterization, and incision of the sling or urethrolysis. Some investigators recommend conservative therapy for postoperative voiding dysfunction for ≤3 months before surgical revision is attempted. Most patients resume normal voiding following midurethral slings within 1 to 2 days of the procedure. However, some patients may be delayed for 1 to 2 weeks and those with a history of prior SUI surgical procedures or those undergoing concomitant prolapse repair may be further delayed. A prolonged time to intervention for BOO may be associated with long-term, potentially irreversible bladder dysfunction, even following successful urethrolysis.
As compared with obstructive symptoms such as hesitancy, straining, and poor force of urine stream, overactive bladder symptoms resulting from iatrogenically induced BOO following an anti-UI surgical procedure are less likely to improve despite a technically successful operation. In one series, voiding symptoms resolved in 82% of obstructed patients following urethrolysis, whereas overactive bladder (storage) symptoms resolved in only 35%. In this series, increased time to intervention did not correlate with persistence of OAB symptoms after urethrolysis.
Once the diagnosis of BOO is considered or established, options include long-term intermittent urethral catheterization, transvaginal or retropubic urethrolysis, or transvaginal incision of the sling. Care must be taken to avoid urethral injury while performing a sling incision because the urethral wall may be draped over the taut sling and may be inadvertently pinched and perforated during dissection and isolation of the sling for incision. Generally, the longer the time from sling surgery to sling incision, the more difficult it can be to find the sling during repeat exploration. Following isolation and division of the sling, the edges of the cut sling often separate by 1–2 cm, a finding indicating a satisfactory result. Iatrogenic obstruction resulting from autologous fascial slings is often treated in this manner as well. However, historically, some investigators waited up to 3 months before consideration of sling incision for obstructing fascial slings ( Fig. 49.3 ).
