Urinary Incontinence
last authored:
last reviewed:
Introduction
Urinary incontinence is a syndrome that increases with age and costing alomst $20billion US yearly.
Acute, or transient, incontinence, begins suddenly and is usually reversible.
Chronic incontinence can be thought of as urge, stress, overflow, mixed, and functional.
Stress incontinence is the involuntary loss of urine during increased intra-abdominal pressure (coughing, laughing, sneezing, exercising). It occurs with a weakened pelvic floor and resulting bladder outlet hypermobility.
Functional incontinence is caused by an inability or a lack of motivation to urinate in a toilet.
Urge incontinence is the involuntary loss of urine preceded by a strong urge to void, whether or not bladder is full. It is the most common type.
Mixed incontinence occurs with stress and urge incontinence.
Overflow incontinence results from detrusor muscle weakness or bladder outlet obstruction.
Incontinence is a common reason for non-compliance of diuretics or ACE inhibitors.
The Case of...
a simple case introducing clincial presentation and calling for a differential diagnosis to get students thinking.
Causes and Risk Factors
Stress incontinence can be caused by:
- displacment of the UVJ from its normal anatomic location; can occur following delivery, surgery
- intrinsic spincter deficiency (less common)
- urethral surgery or radiation in men
Urge:
- detrusor overactivity (age-related, idiopathic, CNS lesions
- bladder irritants (infection, caffeine, cola, foreign bodies: sutures etc; poor PO intake)
Overflow inclontinece: obstruction of the urethra
- BPH
- prolapse
- surgery
- anticholinergics, narcotics, alpha-adrenergic agonists
Fistula: vesicovaginal or ureterovaginal fistulas (obstructed labour)
Functional causes include:
- inaccessible toilets
- mobility disorders
- cognitive impairment
- psychological factors
- infection
- diabetes
- constipation
- atrophic vaginitis
- neurological disease
- drugs
Pathophysiology
Urination requires somatic and autonomic signals to travel from the full bladder to the spinal cord.
The cerebral cortex is predominantly inhibitory, while the brain stem coordinates sphincter relaxation and detrusor contractor.
As the bladder fills, the SNS closes the bladder neck, relaxes the dome, and inhibits the PNS. Somatic nerves tighten the pelvic floor.
During urination, SNS tone decreases and PNS-related acetylcholine causes bladder contraction.
The normal bladder capacity is 300-500 ml, and the urge to void generally begins at 150-300 ml.
Continence requires intact physiology and functional capacity.
Urge incontinence can combine detrusor overactivity with impaired contractility
Signs and Symptoms
- history
- physical exam
History
Review of systems should include "Do you have trouble with your bladder?" or "Do you lose urine when you do not want to?"
Identify reversible causes
Focus on:
- characteristics of incontinence (bladder records or voiding diaries)
- most bothersome symptoms
- treatment goals and preferences
Overflow incontinence results in dribbling, weak stream, intermittency, hesitancy, frequency, and nocturia.
Voiding difficulty
Pain, dysuria, hematuria
fluid intake
bowel habits
Physical Exam
General volume status (signs of heart failure)
Neurological
Abdominal (palpable bladder)
Rectal (sphincter tone, impaction, masses, prostate)
Pelvic (atrophy, vaginitis, prolapse, mass, tenderness)
Cough test
Investigations
- lab investigations
- diagnostic imaging
Lab Investigations
Measurement of voided volume
urinalysis
urine culture
Diagnostic Imaging
A post-void residual (PVR) may be helpful; <50ml is normal; >200ml suggests inadequate emptying
- bladder ultrasound
- in/out catheterization
pad-test
cystoscopy/urethroscopy
urodynamics
Differential Diagnosis
Incontinence is difficult to confuse with other conditions, but the list should include:
Treatments
Treatment depends on cause and patient preferences.
Conservative
- pessaries
- medications: estrogens, alpha-adrenergics, duloxetine
- functional changes: safe lighting, urinal, bedside commode)
- modify diuretics and fluids
Surgical
- burch colposuspension (open or laparoscopic)
- mid-urethral sling (TVT)
- sub-urethral slong
- trans-urethral injections
Behavioural
Patient dependent
- pelvic floor (Kegel) exercises
- Caregiver: regular toileting, prompted voiding
Medications
Urge: antimuscarinics (oxybutynin, darifenacin, solifenacin)
- anticholinergic medication used to relieve urinary and bladder difficulties, including frequent urination and inability to control urination (urge incontinence), by decreasing muscle spasms of the bladder.
BPH: alpha-adrenergic antagonists (alfuzosin, doxazosin, tamsulosin)
Urge incontinence
- caffeiene and nicotine out
- bladder drill
- anti-cholinergics
Undergarments
Can be helpful, but also expensive. In/out catheters or indwelling catheters
Consequences and Course
Incontinence has many consequences. These include:
- skin irritation
- recurrent UTIs
- falls
- sleep disruption
- isolation and social withdrawal
- depression
- anxiety
- dependency
- increased caregiver burden
- costs (pads, diapers, surgery, devices)
Resources and References
any good free online resources for further reading.
Topic Development
created:
authors:
editors:
reviewers:
 |