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Stress Urinary Incontinence
Introduction
The International Continence Society (ICS) defines SUI as the complaint of involuntary leakage on effort or exertion, or on coughing or sneezing.
Stress Urinary Incontinence
Normally, at rest the intraurethral pressure is greater than the intravesical pressure. The pressure difference between the bladder and the urethra is known as the urethral closure pressure. If intra-abdominal pressure increases as it does with a cough, sneeze, or strain, and if this pressure is not equally transmitted to the urethra, then continence is not maintained and leakage of urine occurs. What is thought to cause this inequity of pressure transmission is not universally accepted, and the discussion of the proposed mechanisms are beyond the scope of this section.
Treatment of Stress Urinary Incontinence
For most patients with SUI, consideration of the simplest, least invasive, and least costly interventions is appropriate (Table 45-6). Dietary measures can be instituted, with identification of items that can be modified. Reduction in consumption of caffeinated beverages and alcoholic drinks should be encouraged. Fluid restriction in patients without chronic medical problems, such as cardiovascular, renal, or endocrinologic disease, can be attempted. Timed voiding to prevent filling the bladder to a capacity that causes urine loss should be undertaken with the use of a urine diary. The diary can also facilitate discussion between patient and clinician as therapy progresses.
Pelvic floor muscle exercises or Kegel exercises have been found to be extremely helpful in patients with mild to moderate forms of incontinence. Focused repetitive voluntary contractions of the levator ani muscles (pubococcygeus, coccygeus, and iliococcygeus) created by having the patient contract or "squeeze" the muscle as if to prevent the passage of rectal gas is an effective therapy. The contractions exert a closing force on the urethra and increase muscle support to the pelvic organs. The patient should be provided written and verbal instructions on performing the exercises. Repetitions, with each contraction held for 3-5 seconds alternated with periods of relaxation, should be begun at 45-100 repetitions daily. In settings in which the patient is motivated and has individual instruction and thorough follow-up and support, results for cure or improvement of bladder control (reduction in urine loss) can be up to 75%.
1. Biofeedback - Biofeedback is an adjunct to pelvic floor exercises that is used to facilitate the patient's comprehension of the proper muscles to contract. By using a pressure catheter and myographic monitoring, a visual or auditory signal of the physiologic response can be provided to the patient to help refine exercise skills. Using surface electromyography on the perineum to measure levator contraction and a pressure monitor in the vagina or rectum to indicate abdominal pressure, the patient can be instructed to preferentially contract the pelvic floor without concomitant abdominal contraction. Studies using a variety of techniques demonstrate a 54-95% cure rate or improvement in SUI. The efficacy of this modality is highly dependent on patient motivation and compliance. Pelvic floor muscle exercises with or without biofeedback require continued implementation and practice or effectiveness will wane.
Stress Urinary Incontinence
The International Continence Society (ICS) defines SUI as the complaint of involuntary leakage on effort or exertion, or on coughing or sneezing ...
2. Electrical Stimulation - As an alternative to active patient contraction of the levator muscles, electrical stimulation of the muscles via small electrical currents can be used to help both SUI and mixed incontinence. Using intravaginal or transrectal electrodes with stimulators, the pelvic muscles automatically contract and are thereby artificially "trained." When used long term, weakened muscles are strengthened and innervation re-established during activation. Experiences with the devices are variable, but they generally show a positive impact on incontinence and acceptable patient tolerance.
3. Pessaries - Intravaginal devices or pessaries to correct the anatomic deficits associated with stress incontinence have long been used to address this vexing problem. Many devices have been proffered, but long-term solutions to incontinence have yet to be proven in the general population. Pessaries, traditionally used for treatment of genital prolapse, have also been shown to have a potential role in supporting the bladder neck and urethra and preventing stress incontinence. Many pessary devices designed to fit within the vagina and elevate the bladder neck are available. Continence can often be achieved because many devices adequately obstruct the bladder neck and urethra. As with all intravaginal devices, maintenance is essential to avoid urinary obstruction and vaginal erosion if the pessary is too compressive.
Urinary Incontinence
- Urinary Incontinence
- Anatomy
L Introduction
L Neuroanatomy - Urinary Incontinence - Overview
L Definition
L Etiology
L History
L Patient Questionnaires
L Voiding Diary
L Urinalysis
L Physical Examination
L Cotton Swab Test
L Urinary Cough Stress Test
L Neurologic Examination
L Urodynamics
L Cystourethroscopy
L Imaging Tests - Stress Urinary Incontinence
L Introduction
L Treatment - Urge Urinary Incontinence
L Definition
L Etiology
L Diagnosis
L Treatment - Mixed Incontinence
L Introduction
L Treatment - Overflow Incontinence
L Definition
L Etiology
L Diagnosis
L Treatment - Bypass Incontinence
- Diverticulum
- Functional and transient incontinence
Occlusive devices are commercially available. External devices, such as urethral plugs that are placed over the external urethral meatus or internal occlusive devices placed transurethrally with an internal balloon, are available and have been shown to be partially helpful in reducing wetting episodes.
Surgical treatment should be offered for moderate to severe incontinence. Urinary incontinence is not a life-threatening condition, and the decision to operate must be based on the patient's symptoms and the impact on daily life. Many patients are able to tolerate slight urine loss, and what often provokes a desire for treatment is an increase in loss above a tolerable threshold. If medical management to improve bladder control is possible and symptoms are reduced to below this threshold, then medical management is most desirable. If not, surgery should be considered.
At least 130 operative procedures have been described for treatment of female urinary stress incontinence. It is therefore not surprising that many of these procedures have not resulted in long-term success. For patients who desire surgical correction, the options can be categorized by method of surgical approach (Table 45-7). Common to most surgical procedures is restoration of bladder neck support by elevation of the urethrovesical junction. Some procedures reconstruct bladder neck supports and provide a stable suburethral layer.
Assessment of the cure rate of any surgical treatment for genuine stress incontinence must take into account the selection of patients, accuracy of the preoperative diagnosis, length of postoperative follow-up, and criteria for cure. Reported cure rates for abdominal procedures range from 60-100%, with 75-90% being the generally accepted rate. Most failures appear to result from incorrect preoperative diagnosis, poor surgical technique, and healing failures.
1. Anterior Repair - Anterior colporrhaphy with Kelly plication is one of the oldest methods of surgical correction, introduced in 1914. Used for anterior vaginal defects (cystocele), the technique involves vaginal dissection of the epithelium below the bladder and bladder neck, identifying the perivesical fascia and pubocervical fascia, and plicating each side over the midline. The Kelly plication involves specific support at the bladder. Numerous studies have evaluated this approach, and long-term analysis does not support this method as an effective cure for stress incontinence, with greater than 60% failure rates over 5 years.
2. Needle Urethropexy - Since the introduction of this procedure in 1957 by Armand Pereyra and its modifications with contributions by Thomas Lebherz, needle urethropexy has become a fixture in anti-incontinence surgery. Numerous authors have published alterations of this technique (eg, Raz, Stamey, Gittes, and Musznai). All rely on vaginal incision, dissection and mobilization of periurethral tissues, entry into the space of Retzius (retropubic space), and passage of a needle ligature carrier from a small abdominal incision into the vaginal incision. The periurethral tissues and fascia are identified, secured with delayed absorbable suture, and brought through retropubically and secured above the abdominal rectus fascia. In this manner the bladder neck is elevated and continence restored. The heterogeneity of procedure and technique make generalized statements about this procedure difficult, but prospective long-term studies for individual procedures are available. The procedures appear to be effective initially, with cure rates of approximately 80-85% with variable follow-up. When examining some studies (including 1 large prospective study) with at least 2 years of follow-up, the cure rates drop dramatically to less than 65%.
3. Abdominal Retropubic Colpopexy - The Marshall-Marchetti-Krantz (MMK) and Burch colposuspension are the two classic retropubic surgeries for incontinence. They share the same mechanism of correction. First, both suspend the periurethral and paravaginal tissue at the level of the urethrovesical junction, and second, both use a firm point of attachment for fixation of these suspension sutures. In the MMK procedure, the sutures are fixed to the periosteum of the pubic bone, and in the Burch procedure, the iliopectineal ligament (Cooper's ligament) (Fig 45-6). The Burch colposuspension has become the first choice for treatment of patients with hypermobility of the bladder neck and genuine SUI. In both longitudinal studies and randomized comparative trials against other procedures, the Burch procedure maintains the highest objective and subjective cure rates of 80% after 5 years and 68% after 10 years of follow-up.
A laparoscopic approach to Burch colposuspension offers the benefit of minimally invasive surgery with the same level of efficacy. With the laparoscopic approach, hospital stay and postoperative recovery are minimized. Using the transperitoneal or preperitoneal approach, this method has demonstrated cure rates comparable to the open procedure. Success rates with variable follow-up range between 87% and 97%, with 85% at 5 years of follow-up reported by 1 prospective study. The procedure requires advanced laparoscopic skills, and the results are highly dependent on the skill of the operator. Accordingly, some reports report lower cure rates and higher complications compared with the open procedure.
4. Suburethral Slings - The suburethral sling was one of the original surgical procedures developed for correction of SUI. The SUI concept of restoring continence by encircling the urethra with supportive tissue, either from the patient or foreign material, was introduced at the beginning of the 20th century. Contemporary techniques have used a patient's own fascia harvested from the leg or rectus fascia, or donor fascia in the form of cadaveric fascia lata. Cure rates of suburethral sling procedures for genuine stress incontinence vary from 70-95%. Reported rates vary because of the heterogeneity of patients, and many are previous surgical failures. Variations in sling material and technique have made cure rates among sling techniques difficult to interpret. Furthermore, most studies vary in the definition of cure and may not distinguish between cure and improvement.
In a large review study summarizing cure rates of surgical treatments for SUI, 16 studies comparing sling procedures to colposuspension were reviewed. Of the 4 that were randomized controlled trials comprising 150 patients, none reported a difference in cure. The remaining 12 were retrospective studies, with only 1 demonstrating a difference in outcome between procedures, 79% versus 95% cure for sling and colposuspension, respectively.
5. Midurethral Slings - The latest modification of the sling is the use of tension-free vaginal mesh made of polypropylene placed at the level of the midurethra. This pioneering technique, developed in Sweden, was introduced to the United States in the late 1990s. Use of tension-free vaginal tape (TVT) (Fig 45-7) was developed as a minimally invasive technique for surgical correction of genuine SUI. The initial study had an 84% cure rate in 75 women with 2-year follow-up. Considerable data now support a high subjective cure of 85-93% and objective cure rate of 75-85% with up to 7-year follow-up.
Because of the success of TVT, numerous other devices using the same principles and technique have been introduced. All use a polypropylene mesh but have different designs of delivery needle/trocar, mesh construction, and sheath type. Comparative data between devices are scanty.
The newest variation of the midurethral sling is the transobturator approach. Rather than retropubic passage, the sling is passed through the obturator foramen laterally. This creates a more lateral point of fixation. The purported advantage is reduction in bladder, bowel, or major vascular injury because this method avoids the space of Retzius and does not traverse the peritoneal space. Early data suggest similar short-term cure rates to retropubic passage (94%). Long-term comparative studies will determine the role of the transobturator approach as a viable alternative to retropubic midurethral slings (Fig 45-7).
C. PERIURETHRAL AND TRANSURETHRAL INJECTION
Periurethral or transurethral injection of a bulking agent into the submucosal space of the bladder neck causes narrowing or coaptation of the proximal urethra and bladder neck opening. This increases urethral resistance to involuntary urine loss without changing resting urethral closure pressure. Currently glutaraldehyde cross-linked bovine collagen is the most commonly used material. This procedure is generally reserved for genuine SUI caused by intrinsic sphincteric deficiency. The injections can be performed with the patient under sedation with local anesthetic in an outpatient or office setting. The bovine collagen degrades over 9-19 months, and repeat "booster" injections are often required. Improvement and cure rates are very high in the short term, and complications are minimal. Pyrolytic carbon beads (Durasphere) is a permanent and hypoallergenic bulking agent that may obviate the need for repeat injections, but long-term cure rates are equally disappointing. Newer formulations are being introduced. Inert gel formulations that become firm after injection are being studied in clinical trials.
The artificial urethral sphincter is an effective option for patients with incontinence not amenable to standard surgical treatment because of urethral scarring or atony. The artificial urinary sphincter is best used in patients with incontinence due to poor urethral sphincter function. The sphincter obstructs the urethra by compressing the bladder neck via a pressure-regulated balloon and releases the compression when the patient desires to void. Reported success rates are up to 91%, but complication rates are high, with 21% of patients requiring surgical replacement of parts or the entire sphincter.
Figure 45-6. Abdominal surgical procedure to correct stress incontinence. A: Anterior vaginal wall has been mobilized. Two sutures have been placed on either side and far lateral from the midline. Distal sutures are opposite the midurethra. Proximal sutures are at the end of the vesicourethral junction. Sutures are attached to Cooper's ligament. B: Cross-section shows urethra free in the retropubic space, with anterior vaginal wall lifting and supporting it. C and D: Urethra is compressed and strangulated against pubic bone when vaginal sutures are applied close to the urethra and then fixed to the pubic symphysis. (Reproduced, with permission, from Tanagho EA: Colpocystourethropexy. J Urol 1876;116:751. Copyright 1976 by The Williams and Wilkins Co.)
Figure 45-7. A: Placement of midurethral sling in the sagittal view. B: Retropubic passage of midurethral sling. C: Transobturator passage of midurethral sling.
