Urinary Retention

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Causes of urinary retention

• Acute retention
  • Prostate pathology – benign or malignant
    • Commonest cause in men is benign prostatic hypertrophy (BPH)
  • Infection including STI
  • Phimosis, circumcision
  • Congenital urethral valves
  • Clot retention from bleeding source
  • Urethral strictures
  • Constipation
  • Post-operative
  • Neurological
    • Cauda equine syndrome, any spinal injury above level of bladder innervation
  • Medications
    • Anticholinergic, opiate, antihistamines, cold/flu remedies medication
  • Alcohol
• Chronic retention
  • Prostate pathology (as above)
  • Pelvic mass
    • Benign or malignant
  • Diabetes
  • Neurological
    • MS or other chronic upper motor neurone pathology

History taking in urinary retention

• Presenting complaint
  • Acute retention
    • Rapid onset suprapubic pain (if painless and acute suspect CNS pathology)
    • Inability to pass urine
    • Possible bleeding
    • Symptoms in keeping with aetiology
      • e.g. recent dysuria, recent spinal trauma
  • Chronic
    • May be as above but more likely:
    • May be asymptomatic
    • Low flow micturition
    • Nocturnal incontinence
    • Palpable painless bladder
    • Clinical signs of chronic renal failure
• History of presenting compliant
  • UTI symptoms
  • Timing and speed of symptoms
  • Pain site and severity
  • Desire to void
  • Sensation of incomplete voiding
  • Previous episodes of retention
  • Recent surgery
  • Bowels opening
• Past medical history
  • Diabetes
  • Known prostate disease
  • Urinary tract tumour/any cancer
  • Neurological disease e.g. disc prolapse, MS etc
  • Known anatomical distortion
  • PMHx will also help determine fitness for future surgery
• Medications
  • Anticholinergics e.g. oxybutynin
  • TCAs
  • Opiates
  • Antihistamines
  • Cold remedies
  • Anticoagulants if bleeding
• Allergies
• Social history
  • Smoking
  • Risk factors for malignancy

Focused examination in urinary retention

• ABCDE approach to ensure patient safe
• Abdominal examination
  • Is the bladder either visible or percussible
    • A percussible bladder has at least 150mls in it
  • Is the bladder palpable?
    • A palpable bladder has over 200mls in it
  • Any other abdominal masses palpable?
  • PR exam
    • Prostate size and prostate texture (smooth = BPH, craggy = tumour)?
    • Anal tone?
    • Faecal impaction?
• Focused neurological examination
  • Looking for potential spinal lesion, MS (a rare primary presenting complaint in MS), other neurological condition that can be associated with dysautonomia e.g. Parkinson’s

Initial investigation of urinary retention

• Urine dip and MSU
• U&Es, FBC and clotting (G&S if frank haematuria)
• Blood glucose
• Consider PSA if suspicious prostate
• Post-catheter
  • Measure residual volume of bladder
  • Measure urinary volume removed in first 10-15 minutes to determine true acute retention versus “acute on chronic” retention
  • Residual volumes of greater than one litre make patients more likely to fail a trial without catheter (TWOC) and increase the chances of have recurrent retention

Further investigation of urinary retention

• Renal tract USS if very high residual or abnormal renal function on bloods
• CT if space occupying lesion suspected
• Cystoscopy if urethral/prostate disease suspected
• Urodynamic studies if bladder dysfunction suspected

Initial management of acute urinary retention

• Acute retention
  • Catheterise patient
    • Aseptic technique
    • Consider stat dose of gentamicin (80mg IM if no renal failure) if high risk for UTI
  • Post-catheterisation patients may be admitted if:
    • Clot retention
    • Complicated renal colic
    • Frank haematuria
    • Social reasons or lots of co-morbidities
    • Greater than two litres of residual urine
  • Post-catheterisation patients may be sent home if they have none of the issues above
  • On discharge
    • Urgent follow-up if suspected malignancy, mild haematuria, very abnormal U&Es
    • Non-urgent (usually 2-4 weeks) if uncomplicated UTI, mild prostate pathology.
    • Academic debate regarding how long to leave catheter in: some advocate immediate removal once drained, others leave in for up to 2 weeks before attempting trial without catheter (TWOC)
    • In men, give Tamsulosin (400mcgs PO) as a stat dose prior to TWOC. Consider starting long term alpha blockers after discussion with urology.
    • Suprapubic catheterisation should be discussed with urology if catheterisation fails.
  • Treat the cause
    • As above, tamsulosin for BPH
    • Antibiotics for UTI
      • Trimethoprim or nitrofurantoin as per local trust policy
    • Treatment of constipation
      • Movicol 3 sachets twice per day, increased dietary fibre
    • More complex causes will need discussion with relevant team
• Chronic retention
  • Less urgency
  • Catheterise if renal dysfunction or hydronephrosis: be wary of over diuresis requiring intravascular support and monitor electrolytes
  • Management is very specific to cause but tend to avoid TWOC until definitive treatment is available due to poor outcome of TWOC in chronic retention.

References

• Kalejaiye, Odunayo, and Mark J. Speakman. “Management of acute and chronic retention in men.” European urology supplements 8.6 (2009): 523-529.
• Selius BA, Subedi R. Urinary retention in adults: diagnosis and initial management. Am Fam Physician 2008; 77: 643-650.
• McNeill, S. A., et al. “Alfuzosin 10 mg once daily in the management of acute urinary retention: results of a double-blind placebo-controlled study.” Urology 65.1 (2005): 83-89.)

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