126 CHAPTER 4 Incontinence
“Mixed” incontinence
Definition
Mixed incontinence is involuntary urinary leakage associated with both urgency and exertion, effort, sneezing, or coughing (UUI + SUI). Roughly 30–50% of women with SUI also have symptoms of frequency, urgency, or UUI.
Underlying etiologies and evaluation remain the same as for SUI and UUI (see p. 20).
SUI component
Risk factors for women include childbirth (increased with forceps delivery); aging; estrogen withdrawal; previous pelvic surgery; and obesity. There also appears to be an intrinsic loss of urethral strength, often associated with urethral hypermobility. Neurological disorders (SCI, MS, spina bifida) also cause sphincter weakness.
Investigation and management
This mixed UI patient group needs further investigation to rule out pathologies such as bladder cancer, stones, and interstitial cystitis. Voiding records and urodynamic studies are most useful.
•Behavioral and pelvic floor exercises with vaginal weights (Kegel exercises) are important and can improve symptoms in 30% of women with mild SUI.
•Biofeedback is the technique by which information on ability and strength of pelvic floor muscle contraction is presented back to the patient as a visual, auditory, or tactile signal. Patients may also be helped by the perineometer, which measures pelvic floor contraction.
•Correct pelvic organ prolapse with a pessary.
When stress symptoms predominate, surgical repair via a sling can alleviate symptoms. However, if UUI is also a significant symptom, surgery may be less helpful, and a trial of pharmacotherapy should be used first.
This page intentionally left blank
128 CHAPTER 4 Incontinence
Post-prostatectomy incontinence
Incidence
After TURP or open prostatectomy (OP) performed for benign prostate disease, <1% of patients will have significant SUI.1
Results after radical prostatectomy (RP) for malignant disease are more variable—up to 40% suffer mild urinary leakage requiring pads, but this usually improves over 12–18 months post-surgery, with severe UI persisting in 2–10%.2,3
Risk factors
Risk factors include increasing age; pre-existing bladder dysfunction; previous radiotherapy (TURP following brachytherapy has a 40% risk of severe UI); prior TURP; advanced stage of disease; and surgical technique.
Earlier recovery of continence after RP is achieved using nerve-sparing techniques and sphincterand bladder neck–preserving procedures.
Pathophysiology
The proximal sphincter mechanism is removed at prostatectomy. Postprostatectomy continence therefore requires a functioning distal urethral sphincter mechanism and low bladder pressure during bladder filling. Direct damage to the external sphincter can occur during prostatectomy (at TURP it occurs particularly during resection between the 11 and 2 o’clock position, when the reference point for the position of the distal sphincter—the verumontanum—cannot be seen).
Damage to the innervation of the sphincter can occur during both open prostatectomy and TURP. Urodynamic studies before and after RP show that maximal urethral closure pressure (MUCP) and functional urethral length (the length of urethra over which the sphincter functions to maintain high pressures) both fall predictably.
Nerve-sparing RP (where the neurovascular bundles are specifically identified and preserved) produces better continence rates and longer functional urethral lengths and MUCPs.
A substantial proportion of men also have overactive bladders (detrusor instability) before prostatectomy, and this may remain so after prostatectomy, often taking months to resolve after successful surgery for BPH. The main cause of post-RP incontinence is sphincter dysfunction.
Evaluation
Wait for up to 12 months’ spontaneous improvement unless incontinence is severe.
•History: stress-induced leakage (cough, standing from a sitting position) suggests sphincter dysfunction.
•Examination: observe for leakage while patient is coughing in standing position and note the severity.
•Tests: post-void residual volume measurement on ultrasound (to exclude retention with overflow); urodynamic studies allow determination of bladder overactivity and sphincter function
POST-PROSTATECTOMY INCONTINENCE 129
•Cystoscopy allows identification of strictures (this is particularly important if artificial sphincter implantation is contemplated, since it is preferable to stabilize the stenotic vesicourethral anastomosis prior to undertaking AUS placement).
Treatment
Sphincter dysfunction
The AdVance transobturator male urethral sling is an effective new transobturator polypropylene sling that has recently been developed for men with mild to moderate incontinence (1–3 pads per day). Alternatively, pelvic floor exercises, urethral bulking agents, and bone-anchored slings may be used.
Artificial urinary sphincter insertion is usually deferred until 1 year post-prostatectomy and is the most effective long-term treatment (80% success rate). It is used primarily in men with considerable leakage (>3 pads per day).
Bladder dysfunction
Conservative treatment for bladder overactivity includes behavioral therapy, pelvic floor exercises, and anticholinergic medication.
Surgery for intractable cases includes augmentation cystoplasty or urinary diversion. Catheterization may be considered in the older patient.
1 Agency for Health Care Policy and Research (AHCPR) (1994). Benign Prostatic Hyperplasia: Diagnosis and Treatment. Clinical Practice Guidelines No. 8 Feb. www.ncbi.nlm.nih.gov.
2 Catalona WJ, Carvalhal GF, Mager DE, et al. (1999). Potency, continence and complication rates in 1,870 consecutive radical retropubic prostatectomies. J Urol 162(2):433–438.
3 Walsh PC, Marschke P, Ricker D, et al. (2000). Patient-reported urinary incontinence and sexual function after anatomic radical prostatectomy. Urology 55(1):58–61.
130 CHAPTER 4 Incontinence
Vesicovaginal fistula (VVF)
A fistula is an abnormal communication between two epithelial surfaces, in the case of a VVF, between the bladder and vagina. In 10% of patients there is a coexisting ureterovaginal fistula.
Etiology
In developing countries, most cases are associated with obstructed or prolonged childbirth, causing tissue pressure necrosis between the vagina and bladder. In developed countries, 75% of cases follow hysterectomy (0.1–0.2% risk)1,2 (Fig. 4.1).
Other causes include pelvic surgery (e.g., bowel resection); radiotherapy; pessaries; advanced pelvic malignancy (cervical carcinoma); pelvic endometriosis; inflammatory bowel disease; trauma (pelvic fracture); childbirth (5%); low estrogen states; infection (urinary TB); and congenital abnormalities.
Symptoms
These include immediate or delayed onset of urinary leakage from the vagina postoperatively, prolonged bowel ileus (due to leak of urine into the peritoneal cavity as well as through the vagina), and suprapubic pain or flank pain.
Examination
•Vaginal examination may demonstrate the VVF, if large (the examining finger can reach inside the bladder).
•3-swab test—oral phenazopyridine turns urine orange. After 1 hour, place 3 swabs into the vagina and instill methylene blue into the bladder. If the proximal swab turns blue, it indicates VVF; if it is orange, it suggests ureterovaginal fistula.
•Cystogram (or voiding cystourethrography [VCUG]). This is the best test for identifying fistulae.
•Fistula track may be seen at cystoscopy and can help in determining its proximity to the ureteric orifices. Biopsy the tract if there is a history of malignancy.
•IVP and/or bilateral retrograde pyelograms are essential to assess ureteral involvement.
Management
Most cases require surgery. Conservative methods include urethral catheterization combined with anticholinergics and antibiotics for small, uncomplicated VVF. Alternatively, de-epithelization of the tract can be attempted with silver nitrate or electrocoagulation.
If there is a coexisting ureterovaginal fistula, a ureteric stent alone is often successful.
Surgery
Early repair (within 2–3 weeks) is advocated in simple cases, but traditionally, surgery is delayed 3–6 months. The transvaginal approach has success rates of 82–100%. The fistula tract is closed with two layers of sutures and covered by an anterior vaginal wall flap.
VESICOVAGINAL FISTULA (VVF) 131
Figure 4.1 Cystogram showing leak of contrast from the bladder and into the vagina due to a VVF. This followed a hysterectomy.
Additionally, interpositional tissue grafts should be mobilized between the bladder and vagina (Martius fat pad graft from labia majora; peritoneal flap; gracilis flap).
The abdominal approach is reserved for complex cases. The bladder is bisected to the level of the fistula tract, which is then completely excised (85–90% success). The bladder is closed and an interpositional omentum graft created. In complex cases, urinary diversion procedures may be needed.
Postoperatively, maximal urinary drainage is prudent using a large-bore Foley catheter and possibly a suprapubic catheter and/or ureteral catheter. Antibiotic coverage and anticholinergics are maintained for 2 weeks until catheters are removed. A VCUG should be performed to document the absence of extravasation. Give estrogen replacement to postmenopausal women. Patients should avoid use of tampons or sexual intercourse for 2–3 months.
Postoperative complications include vaginal bleeding; infection; bladder pain; dyspareunia due to vaginal stenosis; graft ischemia; ureteric injury; and recurrence.
1 Tancer ML (1992). Observations on prevention and management of vesicovaginal fistula after total hysterectomy. Surg Gynaecol Obstet 175(6):501–506.
2 Harris WJ (1995). Early complications of abdominal and vaginal hysterectomy. Obstet Gynaecol Survey 50(11):795–805.