Urinary retention Flashcards
What is urinary retention?
Inability to pass urine. Either chronic or acute
What is acute urinary retention?
Acute urinary retention is defined as a new onset inability to pass urine, which subsequently leads to pain and discomfort, with significant residual volumes.
What are risk factors for acute retention?
POST-SURGICAL
Older male patients with BPH or prostate cancer
Ureteric stone impaction or strictures
Medications e.g. anti-cholinergics, spinal/epidural anaesthesia
Peripheral neuropathy, SCI
What are risk factors for post-surgical urinary retention?
• Age >50yrs
• Male gender
• Previous retention
• Type of surgery
• Including pelvic or urological surgery
• Anaesthetic type (spinal or epidural)
• Neurological or urological co-morbidities
Medication (e.g. antimuscarinics, alpha agonists, opiates)
What is chronic retention?
Long-standing bladder distension causes desensitisation, giving minimal discomfort despite large intra-vesical volumes.
What are causes of chronic retention?
• BPH ureteric strictures • Pelvic prolapse • Pelvic masses Neurological causes
What are symptoms of acute retention?
Acute suprapubic pain and inability to micturate, despite feeling need to.
Suprapubic tenderness
Palpable distended gallbladder
May be Sx. of UTI
What is high pressure retention?
High intra-vesicular pressures overcomes anti-reflux mechanism in bladder, causing hydroureter/hydronephrosis
What is low pressure retention?
Upper renal tract is unaffected as urethral valves are competent
What are Sx of chronic retention?
Painless
Distended bladder
LUTS e.g. weak stream, hesitancy
Overflow incontinence, causing nocturnal enuresis
What Ix in retention?
DRE - if prostate enlargement
Post-void bladder scan: shows volume of retained urine
Bloods: U+Es, AKI suggests high pressure
Catheterise and send CSU to see if infection. May need suprapubic
US to see if hydronephrosis (high pressure)
What is initial Rx of urinary retention?
Some post-op patients may resolve spontaneously.
if not, catheter.
treat any cause e.g. infection, tamsulosin for BPH.
monitor fluid balance and urine output for post-obstructive diuresis
What is post-obstructive diuresis
Kidneys make too much urine due to loss of medullary concentration gradient
Can cause worsening AKI
If output >200ml/hour, give IV fluids to prevent AKI
What additional Rx for high pressure acute retention?
Definitive management e.g. TURP needed to minimise scarring of kidneys.
TWOC can be attempted to see if patient voids. If they fail, may need long-term catheter.
What additional Rx for chronic retention?
Likely need permanent catheter.
NO TWOC, as likely will be repeated renal injury.
