I. Components of the system:

  1. Bladder
  1. Dome ("body") lies above a line formed partly by ureteral orifices and post. ridge of the trigone
  2. Base includes trigone, neck, and functional internal sphincter
  1. "Internal urinary sphincter," aka bladder neck
  1. More important for maintenance of continence than external sphincter
  2. Innervated by sympathetic fibers through hypogastric nn.
  3. Interruption of innervation may result in stress incontinence

II. Physiology and pathophysiology

  1. Normal neurologic control of bladder function achieves continence and, during voiding, coordination of detrusor contraction with external sphincter relaxation.
  2. Any neurologic derangement from cortex to pons, cord, & peripheral nn. can result in urinary retention, incontinence, or a combination of both
  3. Descending pathways from midbrain and pons are essential for coordination of detrusor and ext. urethr. sphincter; damage from lesions there or high in spinal cord results in "vesical-sphincter dyssynergia" (see below)
  4. Urinary retention carries with it the complications of infection and hydronephrosis, both of which can result in renal failure
  1. Type of incontinence-Symptomologic categories
    1. Stress incontinence = involuntary leakage from effort or exertion, or sneezing or coughing.  Usually related to poor sphincter function and/or increased urethral mobility.
    2. Urge incontinence = involuntary leakage accompanied or proceeded by urgency. Usually related to detrusor overactivity
    3. Mixed incontinence = features of both
    4. Overflow incontinence = associated with overdistention of the bladder, e.g. form detrusor paralysis or bladder outflow obstruction.
  1. Types of bladder dysfunction-Physiologic categories
  1. Hyperreflexia of detrusor ("Overactive Bladder")
  1. Produces urge incontinence from involuntary strong contractions
  2. Usually small/absent residual volumes
  3. Sensation of bladder fullness usually intact
  4. In addition to neurogenic causes, may be caused by mucosal irritation, (e.g. cystitis, tumor)
  1. Sphincter incompetence
  1. Corticospinal tract interruption will interfere with voluntary interruption of urinary stream (using ext. sphincter)
  2. Sympathetic denervation will interfere with int. sphincter
  3. Surgery & trauma may damage either sphincter
  1. Incomplete bladder emptying
  1. Hyporeflexia/areflexia of detrusor
  1. Produces overflow dribbling,
  2. Also can produce some sx that can be miskaten for mechanical outlet obstruction (hesitancy, decreased flow, postvoid dribbling)
  3. In case of hyporeflexia, there may also be some component of urge incontinence (see above)
  4. High residual volumes
  5. Poor sensation of bladder fullness
  1. Outlet obstruction
  1. Vesical-sphincter dyssynergia
  1. Present in about 50% of each of above groups
  2. Usually have incontinence due to involuntary detrusor contractions
  3. Sometines, ext. sphincter contracts at same time as bladder, looking like bladder outlet obstruction! (sm. voiding volumes, high post-void residual volumes)
  1. Cortical dysfunction (or interruption of cortico-pontine connections) leads to involuntary voiding that is, however, properly coordinated ("precipitous voiding")
  2. Other causes of urinary incontinence
    1. Urethritis
    2. Cystitis
    3. Fistulas
    4. Stool impaction

III. Evaluation of the patient with bladder dysfunction

  1. History
  1. Urologic-may need to keep urinary diary
  1. Sx and h/o UTI's
  2. Urgency and its relationship to incontinence
  3. Constant dribbling suggests ureterovag. or cystovag. fistula
  4. Sx of outflow obstruction (nocturia, double voiding, hesitancy)
  5. Enuresis?
  6. Sx of stress incontinence
  7. Voiding frequently during day but not at night suggests psychogenic
  1. Gynecologic if female
  1. Prolapse
  2. Previous GYN surgery-History of hysterectomy is associated with higher risk of subsequent stress incontinence (Lancet 370:1462, 2007--JW)
  3. Relation of sx to menses or hormonal rx
  4. Dyspareunia
  1. Neurologic
  1. Awareness of full bladder? (Inc. dementia, etc.)
  2. Fecal incontinence
  3. Limb weakness, paresthesias
  1. Drugs: antihypertensives, esp. alpha-blockers and diuretics; progesterone, phenothiazines, anticholinergics, tricyclics, antihistamines, antiparkinsonians, anispasmodics, hormone replacement
  1. Exam
  1. Neurologic exam of LE's, sensation in anal and perianal area (S4-5), plus sphincter tone, bulbocavernosus and anal reflexes
  1. Ext. urinary sphincter has same innervation as anal sph., so if anal sphincter contraction is ok, ext. ur. sphincter prob. is too
  2. If bulbocavernosis is present but vol. contraction is not, indicates lesion above S2 b/c that's where reflex arc goes through
  1. For female patients:
    1. Best to examine with bladder empty, with just lower blade of a Graves' speculum, examining anterior vaginal wall at rest & with Valsalva, per J. Miller of UW
    2. Urethra for signs of inflammation
    3. Vagina for signs of atrophy
    4. Mobility of vagina--?scarring
    5. Prolapse
    6. Anterior vaginal wall relaxation and position of u-v junction
    7. Levator tone
  1. Post-void residual to r/o overflow incontinence--should be checked in pretty much every case
    1. Should be checked after voiding with a FULL bladder
    2. Should be < 100cc, sometimes less if bladder is small
  1. Laboratory studies
    1. CBC, u/a c & s (r/o infection, hematuria)
    2. Serum glucose to r/o DM
    3. Urinalysis and culture
  1. Urodynamics-Can be helpful though in many cases can treat without
  1. Flow rate analysis ("uroflow")--help identify outflow obstruction (flow rate <15ml/sec)
  2. H2O cystometry with/without sphincter EMG--helps differentiate detrusor dyssynergia from stress incontinence
  1. Residual urine should be <50ml
  2. First sensation at 150-200ml
  3. Strong desire to void at 450-500ml
  4. >15cm H2O rise in pressure on standing or coughing
  5. No loss of urine and only slight descent in bladder base on coughing
  6. Rise of < 70cm H2O on voiding, with peak flow rate > 200ml/sec
  7. Ability to stop voiding on command
  1. May need to be repeated periodically if previously successful tx starts to fail
  1. Other diagnostic studies
    1. CT or IVP can help r/o stones or congenital anomaly--esp. if pt has recurrent UTI's
    2. Ultrasound to r/o hydronephrosis
    3. Excretory urography
    4. Cystoscopy-Consider if there is suspiciou of disorders of the urethra or bladder (e.g. hematuria, pyruia, irritative voiding symptoms (e.g. frequency or urgency), or urge incontinence without clear cause
    5. Read Chain urethrocystography-helps with decision on what kind of surgery to do for stress incontinence
    6. Direct electronic urethrocystometry

IV. Treatment

Note-One approach is to initially try for normal complete voiding with no incontinence, and if that's not possible, go either for complete incontinence with complete bladder emptying (to avoid retention) or complete retention with self-catheterization (to avoid incontinence) (Neurology 30:12, 1980)

  1. For urge incontrinence
  1. Anticholinergics
    1. All may cause dry mouth, HA, dyspepsia, constipation, and dry eyes
    2. Contraindications include narrow-angle glaucoma and urinary retention
    3. Specific agents:
      1. Oxybutinin (Ditropan) (5mg BID-TID, XL 50-30mg QD; transdermal 2x/wk)
      2. Tolterodine (Detrol) (1-2mg BID, XL 2-4mg QD)
        1. Tolterodine slightly less effective than oxybutynin but causes less side f/x (Urol. 50:90, 1997--Med. Lett.; Mayo Clin. Proc. 76:358, 2001--JW; Mayo Clin. Proc. 78:687, 2003--JW)
      3. Solifenacin (Vesicare) 5-10mg QD (limit 5mg/d for renal or hepatic impairment)
      4. Fesoterodine (Toviaz)
      5. Darifenacin (Enablex) 7.5-15mg QD
      6. Trospium (Sanctura)
      7. Propantheline
      8. Hycosamine
      9. Tricyclic antidepressants e.g. doxepin
  1. Alpha-adrenergic stimulation (e.g. ephedrine) may increase bladder outlet resistance
  2. Intermittent self-catheterization an option if develops retention
  3. Some surgical treatments exist
  4. Pelvic floor muscle training--At least as effective as anticholinergic meds in one Cochrane systematic review
  5. Bladder training--See below under "Combined Stress/Urge Incontinence"
  6. Electrical stimulation may be helpful with urge incontinence
  1. For stress incontinence
    1. Consider conditions which may exacerbate stress incontinence: constipation, atrophic vaginitis, cystocele
    1. Pelvic floor muscle training (sometimes with internal monitoring and biofeedback; usually performed by a physical therapist)
      1. 107 women (mean age 50yo) with stress incontinence randomized to Kegels (plus weekly group exercise sessions), electrical vaginal stimulation, vaginal cones, vs. no tx; at 6mos; resolution of sx more common in exercise group vs. other groups (BMJ 318:487, 1999--JW)
      2. 200 women 40-78yo randomized to behavioral training, behavioral training + pelvic floor electrical stimulation, or just self-help booklets; after 8wks, reduction in frequency of incontinence episodes was no sig. diff. between the first two groups, each of which was sig. greater than the reduction in the pts who just got the self-help booklets (JAMA 290:345, 2003--JW)
      3. In a study in 52 women > 3mos post-partum with stress incontinence randomized to PT vs. no PT, incidence of control of the incontinence was sig. greater in the PT groups (Obs. Gyn. 104:504, 2004--AFP)
    2. Pessaries
      1. e.g. "Silicone incontinence dish" by Milex
      2. Support the bladder neck; little evidence of benefit
      3. Fit like diaphragms
      4. Must be removed at night
    3. Other devices
      1. "Capsure"--suction cup-like device that covers urethral meatus, increased incidence of UTI's
      2. "Impress"--adhesive patch that covers urethral meatus
      3. "Fem-Assist"--a reusable, silicone, domed cap that covers urethral meatus and held in place by suction. Can cause some discomfort (see Obs. Gyn 92:286, 1998--JW)
      4. "Reliance" (the "plug")
    4. Transurethral injection of silicone microimplants (in cases where the problem is sphincter deficiency) (Obs. Gyn. 92:332, 1998--AFP)
    5. Surgery-Retropubic colposuspension, sling suspensions, anterior colporrhaphy, etc.
    6. Medications: alpha-adrenergic agonists have been shown to be more effective than placebo
  1. For combined stress/urge incontinence
    1. 197 women 55-92y with urge or mixed incontinence randomized to behavioral treatment behavioral tx vs. placebo. With # of incontinence episodes as main outcome, behavioral tx was sig. more effective than drug tx; drug tx was more effective than placebo. The behavioral tx consisted of anorectal biofeedback to help pts identify pelvic mm. and to contract these mm. selectively while keeping abd. mm. relaxed; also how to respond to sensation of urgency by pausing, sitting down, relaxing entire body, and contracting pelvic mm., 4 sessions over 8 weeks (JAMA 280:1995, 1998)
  1. For incontinence due to Hyporeflexia
    1. Try to assist detrusor contraction; n.b. this tx may result in incontinence due to hyperreflexia
    2. Tx may only be successful at preventing retention and not at achieving voluntary micturition, so self-catheterization in usually required in addition to drugs
    1. Suprapubic tapping/scratching may in some cases help stimular detrusor contraction
    2. Bethanechol (cholinergic)
    1. 5-10mg initially; repeat hourly to max total 50mg until response occurs; add total and give it-10-50mg-TID-QID
    2. Take on empty stomach to avoid n/v
    3. Often not helpful
    1. Phenoxybenzamine (alpha-blocker to reduce bladder outlet resistance)-not really proven helpful as of 1983
    2. Diazepam, baclofen (particulary good with vesico-urethral dyssynergia)
    3. Intermittent self-catheterization
  2. Other treatments
    1. Chronic suppressive abx and/or urinary acifiers (Vit C 1g QD; cranberry juice) if recurrent UTI's
    2. Indwelling catheters and surgical urinary diversion-last resort (Indwelling catheters may control incontinence only temporarily, b/c the urethra becomes flopy and urine escapes around catheter, esp. in women)
    3. Fluid restriction including limiting caffeinated beverages (effective in one randomized trial--J. Urol. 174:187, 2005--JW)