Altered Voiding and Urinary Obstruction Flashcards
What are the potential sites that can cause urinary retention/incontinence?
- Brain
- Spinal cord
- Blockages: kidney, ureters
- Lower urinary tract symptoms: bladder, urethra, prostate
- Pelvic floor muscles
- Peripheral nerve lesions
What are the categories of lower urinary tract symptoms (LUTS?)
What conditions/symptoms are included in each one?
Storage LUTS:
- Incontinence
- Urgency
- Frequency (doesn’t necessarily mean more production)
- Nocturia
Voiding LUTS:
- Poor stream
- Hesitancy
- Dysuria
- Intermittency
- Double voiding
- Retention
- Incomplete emptying
- Straining
Post-micturition LUTS:
- Terminal dribbling
Define urinary incontinence
What are the potential impacts of incontinence?
Involuntary loss of urine in sufficient amount or frequency to constitute a social and/or health problem.
- Major cause of morbidity and institutionalisation
- QoL impact
Define stress incontinence
What are its causes?
Occurs when pressure inside the bladder becomes greater than the strength of the sphincters to keep the urethra closed.
Often occurs on effort/exertion or when coughing/sneezing.
Causes:
- Pregnancy/obesity (raised intra abdominal pressure)
- Post child bearing: bladder neck hypermobility/ pelvic floor muscle weakness
Define urge incontinence
What are the causes?
Involuntary urinary leakage accompanied/preceded by an abrupt urge to void that is difficult to control.
Most common cause of urinary incontinence >50 years old.
Causes:
- Usually idiopathic
- Overactive bladder
- Infection
- Bladder stones
- Bladder cancer
- Stroke
- Dementia
- Parkinson’s disease
Define overflow incontinence
What can it be caused by?
Prolonged problems with bladder emptying lead to chronic urinary retention and detrusor muscle failure. Pressure eventually rises due to tissue overdistention and leakage occurs.
Causes:
- Enlarged prostate
- Bladder stones
- Constipation
- Spinal cord injury
Define functional incontinence
What can it be caused by?
Incontinence as the result of something not involving the urinary tract.
Causes:
- Mobility problems
- Dementia
- Diuretics
What focussed questions should be asked when taking a history to quantify urinary symptoms?
- Precipitating events, duration
- Medical/surgical history
- Medications
- Pad usage
What clinical examinations should be carried out on a person with incontinence?
- Pelvic
- Abdomen
- Digital rectal exam
- Neurological
- Mental state
- Mobility
What clinical investigations should be carried out for a person with incontinence?
- Urine dipstick/ MSU
- Urine MC&S
- Cytology
- FBC, U&Es, glucose
- Frequency-volume chart
- Cystometry
Define urodynamics
Study of pressure and flow during storage, transport and expulsion of urine in the lower urinary tract.
How does outflow cystometry work?
Urethral catheter is inserted into bladder and transducer into the rectum.
- Bladder is filled with fluid and pressures recorded in bladder and rectum
- Bladder emptied and pressures recorded
Bladder pressure = combined abdominal and detrusor pressure
Detrusor pressure = bladder pressure - rectum pressure
How is continuous incontinence treated?
- Urinary catheter
- Surgery
How is stress incontinence treated?
- Pelvic floor training
- Surgery
- Incontinence protection
How is urge incontinence treated?
- Avoid stimulants to detrusor muscle
- Bladder retraining
- Anticholinergics: Oxybutynin
- Surgery
How is urinary retention treated?
Restore bladder emptying:
- Intermittent self-catheterisation
- Surgical treatment of outflow obstruction
- Long term catheterisation
- Alpha blockers: Doxasozin
What are the potential causes of urinary retention?
- BPH
- Prostate cancer
- Prostatitis
- Haematuria causing clots (?bladder cancer)
- Tumours
- Bladder stones
- Anatomical/ neurological/ structural
What is benign prostatic hyperplasia?
What are the symptoms?
Benign enlargement of the prostate gland (usually transitional zone)
Can compress urethra causing urinary retention
Can be caused by reduced apoptosis and/or increased proliferation.
Symptoms:
- Hesitancy when urinating
- Difficulty/taking a long time to pass urine
- Weak urine flow
- Stop-start flow
- Urgency/increased frequency
- Urinary incontinence
- Feeling of incomplete emptying
What tool is used to assess potential prostate symptoms?
International prostate symptom score
7 symptom questions:
- Frequency
- Nocturia
- Urgency
- Hesitancy
- Poor stream
- Intermittency
- Incomplete emptying
What clinical examinations/investigations can be carried out to diagnose prostate problems?
PSA (prostate specific antigen). If raised can indicate:
- BPH
- Prostate cancer
- Can be raised following digital rectal exam
- UTI
Abdominal exam
Digital rectal exam
Transrectal ultrasound scan
How is BPH managed?
Watch and wait
Lifestyle adaptations:
- Less alcohol, caffiene and fizzy drinks
- Limit intake of artificial sweeteners
- Exercise
Drugs:
- Selective a1 blocker: doxasozin
Surgery:
- Transurethral resection of the prostate (TURP)
What would a healthy prostate gland feel like on a digital rectal exam?
Smooth
Symmetrical
Even
Soft
What would prostate cancer feel like on digital rectal examination?
Hard
Lumpy
Asymmetrical
Irregular
How are urinary tract stones formed?
Formed as urine is supersaturated with salt. Crystals form which aggregate to form stones. Particle retention (e.g. in stasis) is required in order for a stone to form.
- Crystal growth depends on degree of saturation
- Crystal aggregation depends on collision of small crystals in the urine.
What are the common locations for urinary tract stones to become lodged?
- Pelvic ureteric junction
- Pelvic brim
- Vesicoueteric junction
- Bladder urethral outlet
What are the different types of urinary tract stones?
What type of imaging can be used to detect them?
What shapes are they usually?
Calcium oxalate/phosphate stones
- X-ray
- Large and smooth/ spiky and rough
Struvite stones
- X-ray
- Smooth, brown and softer than other types of stone
Cystine stones
- X-ray
- Crystal shaped, yellow, often staghorn shaped
Uric acid stones
- Ultrasound and CT
- Horn shaped and large
How are calcium oxalate stones formed?
Caused by:
Hypercalciuria:
- Idiopathic
- Rare genetic disorders
- Hyperparathyroidism
- Malignancy
- Sarcoidosis
Hyperoxaluria:
- Primary: genetic
- Secondary: dietary/enteric
What are the risk factors for struvite stones?
All related to UTIs:
- More common in females (higher risk of UTI)
- Indwelling catheters
- Neurogenic bladders
- Urinary tract abnormalities
- Stagnant urine
How are cystine stones formed?
Caused by rare autosomal recessive tubular disorder causing cystinuria
- Cystine not reabsorbed- crystalises
- Occurs in young people
- Causes multiple stones
How are struvite stones formed?
Struvite stones
- Form in alkaline urine that contains ammonia
- Caused by infection from urea-splitting bacteria (proteus mirabilis, klebsiella, pseudomonas)
- Urea is split into NH3 and CO2 by urease
- Causes precipitation of magnesium, ammonium and phosphate to form stone (often staghorn shape)
How are uric acid stones formed?
Accumulation of uric acid in urine from purine metabolism (protein, esp. red meat), alcohol.
Gout (uric acid deposits)
Associated with hyperuricaemia and/or hyperuricosuria
How do urinary tract stones present?
Pain:
- Often ‘loin to groin’ pain (ureteric colic)
- Pelvis refers to loin and back
- Lower ureter refers pain to testis and labium majus
- Lowest pelvic part of ureter refers pain to tip of penis or perineum
- Can radiate to testicles
Haematuria
Vomiting
Irritative voiding symptoms
Important to exclude leaking AAA, pancreatitis, pyelonephritis, diverticular disease.
What initial investigations should be carried out on suspicion of urinary tract stones?
- History:
- Any stones passed
- Previous stones?: type, age at onset, interventions
- Any stones passed
- Urine dipstick
- Urine MC&S
- U&Es, calcium, urate
- If fever: WCC, CRP
- Imaging:
- Urgent
- If fever: immediate (?pyelonephritis)
- X-ray KUB
- USS KUB
- CT KUB
