Continence Flashcards
What is the epidemiology of incontinence?
Most common in:
- Woman
- > 50 years old
What are the broad categories of causes of incontinence?
1 - Extrinsic to urinary system (environment, habit, exercise)
2 - Intrinsic to urinary system (problem with bladder or urinary outlet)
3 - A mixture of both
What structures influence continence?
1 - Bladder & Urethra
2 - Local Innervation
3 - CNS Innervation
What is the functions of the bladder?
- Urine storage
- Voluntary voiding
What muscular structures are responsible for continence?
Bladder - Detrusor smooth muscle
Internal urethral sphincter - Smooth muscle
External urethral sphincter - Skeletal muscle
What happens to the bladder and sphincters during filling of the bladder?
1 - Detrusor muscle relaxes
2 - Sphincters contract
What happens to the bladder and sphincters during voluntary voiding?
1 - Contraction of bladder
2 - Involuntary relaxation of internal sphincter
3 - Voluntary relaxation of external sphincter
What is the sympathetic nerve supply involved in urinary continence?
Beta-adrenoreceptors (T10-L2) - Causes Detrusor to relax (hypogastric nerve)
Alpha-adrenoreceptors (T10-S2) - Causes neck of bladder and internal urethral sphincter to contract (hypogastric nerve)
What is the parasympathetic innervation involved in continence?
S2-S4 (Parasympathetic) - Increases strength and frequency of contractions (pelvic nerve)
S2-S4 (Somatic) - Contraction of pelvic floor muscle and external urethral sphincter (pudendal nerve)
How is the contraction of the bladder by the parasympathetic system overcome to allow storage of urine?
- Centres within CNS inhibit parasympathetic tone and promote bladder relaxation
How are the urethral sphincters controlled in order to ensure continence is maintained?
By a reflex response:
- Increased alpha-adrenergic activity closing internal sphincter
- Increased somatic activity closing external sphincter
Which centres of the CNS are involved in continence?
- Pontine Micturition centre
- Frontal cortex
- Caudal part of spinal cord
What is stress incontinence?
Bladder outlet too weak
What are the features of stress incontinence?
- Urine leak on movement (coughing, laughing, squatting etc.)
- Weak pelvic floor muscles
- Common in woman with children, after menopause
What is urinary retention with overflow incontinence?
When the bladder outlet is ‘too strong’
What are the features of urinary retention with overflow incontinence?
- Poor urine flow, double voiding, hesitancy, post-micturition dribbling
- Blocked urethra
- Older men with BPH
- Treated with alpha-blockers to relax sphincter
- May need to be catheterised
What is urger incontinence?
When the bladder muscle is too strong
What are the features of urge incontinence?
- Detrusor contracts at low volumes
- Sudden urge to pass urine immediately
- Patients know every public toilet
- Can be caused by bladder stones or stroke
- Treated with anti-muscarinics to relax detrusor
What medication is used to treat urge incontinence?
Oxybutinin
What options are there for treating stress incontinence?
1) Physiotherapy - Kegel exercises, Vaginal cones (small weights to help improve pelvic floor strength)
2) Oestrogen cream
3) Duloxetine
What are the 3 main types of incontinence and their key features?
What are the general actions of the drugs used to treat incontinence and give one example of each?
Antimuscarinics (Oxybutinin) - Relax Detrusor
Beta-3 adrenoceptor agonists (Mirabegron) - Relax Detrusor
Alpha-blockers (Tamsulosin) - Relax sphincter and bladder neck
Anti-androgen drugs (Finasteride) - Shrink prostate
What is a neuropathic bladder?
An underactive bladder
What are features of a neuropathic bladder?
- Rare
- Secondary to neurological disease (MS or Stroke)
- Secondary to prolonged cathetarisation
- No awareness of bladder filling, resulting in overflow incontinence
- Only effective treatment is catheterisation
What steps should be followed for assessing incontinence?
1 - Careful history (good SH to assess impact)
2 - Intake chart and output diaries
3 - General examination including rectal and vaginal examination
4 - Urinalysis & MSSU
5 - Bladder scan for residual volume
6 - Consider: incontinence clinic, lifestyle changes, physio or medical treatment
Under what conditions should referal to incontinence clinic be considered?
Failure after 3 months of:
- Pelvic floor exercises
- Vaginal cones
- Habit retraining
- Medication
In what cases could immediate specialist referal be considered?
1 - Vesico-vaginal fistula
2 - Palpable blader after micturition
3 - Disease of CNS
4 - Fibroids, rectocele, cystocele
5 - Severe BPH or prostatic carcinoma
If most treatment options for incontinence fail, what other options are there?
1 - Incontinence pads
2 - Urosheaths
3 - Intermittent or long-term catheterisation
What is a very broad way to divide urinary incontinence?
Bladder - over and under activity
Outlet (sphincter and pelvic floor) - over and under activity
