Acute Urinary Retention
The most common ED presentation is urinary retention due to prostatomegaly in males.
In younger patients with no clear cause, consider a spinal cord lesion—a thorough neurological exam is essential.
These guidelines primarily address male patients with presumed prostatic obstruction (benign or malignant).
Pathophysiology
Causes
- Mechanical Obstruction
- Intraluminal: clot retention
- Wall-related: tumor, strictures
- Extraluminal: prostatic enlargement (most common in males)
- Neurological Disorders
- Especially spinal cord lesions
- Medications
- Notably anticholinergic agents
- Post-operative States
- Secondary to Severe Local Pain
- Herpetic infection
- UTI with severe dysuria
- Constipation
- Psychogenic Retention
- Trauma
- Especially pelvic fractures with urethral rupture
Clinical Assessment
History
- Drug history (e.g. anticholinergics, recent alcohol use)
- Neurological symptoms (e.g. leg/perineal numbness or weakness)
- Hematuria
- Symptoms of prostatism (in males)
- UTI symptoms
- Constipation
- Recent surgery (esp. perianal, colorectal, spinal, urologic)
- Any obvious precipitating factors
Examination
- Confirm retention clinically
- Suprapubic mass with:
- Pain
- Tenderness
- Dull percussion note
- Absent bowel sounds over the mass
- Suprapubic mass with:
- Neurological signs — assess thoroughly
- Rectal exam (males)
- Assess prostate size
- Check anal tone
- Women — check for painful local conditions (e.g. herpes)
Investigations
Blood Tests (if infection or renal compromise suspected)
- FBE
- CRP
- U&Es / glucose
Urine Testing
- CSU for microscopy, culture, sensitivity
Bladder Scan
- Use to confirm diagnosis if clinical uncertainty
Imaging
- Spinal imaging (MRI): if cord compression suspected
- Renal tract ultrasound: for obstruction/renal dysfunction
- CT scan: as guided by suspected pathology
Management
1. Catheterisation
- Insert Foley catheter (or Biocath if outpatient care is likely)
- Allow free drainage – no need to clamp
- Document volume drained
- If >200 mL/hr for 2 hours: suspect post-obstructive diuresis → discuss with Urology
2. Difficult catheterisation
- May require suprapubic catheter → consult Urology
3. Pelvic trauma suspicion
- Perform urethrogram before catheter insertion
Disposition
Admit if:
- Suspected prostatic obstruction
- Requires urological assessment
- Catheter inserted after hours and needs urology nurse education
Safe for discharge if:
- Presumed prostatic obstruction
- Meets ALL of the following:
- No major comorbidities
- Capable of managing catheter at home
- Received education on catheter care by a qualified nurse
- Discharged with a hydrogel-coated Biocath Foley catheter
- Urology follow-up arranged within 1 week
Notes:
- Biocath catheters have a 12-week dwell time, are comfortable, and resist encrustation
- Short Stay admission may be appropriate if discharge criteria not immediately met
If Non-prostatic Causes:
- Ongoing management tailored to underlying pathology
References
FOAMed
- Mackenzie J. Urinary catheterisation (Male) Emergency Procedures App
- Yuminaga J. Difficult urinary catheterisation (Male). Emergency Procedures App
- Cadogan M. Coudé tip catheter. LITFL
- Rezaie S. Urinary Retention: Rapid Drainage or Gradual Drainage to Avoid Complications? RebelEM
Publications
- Delius BA, Subedi R. Urinary Retention in Adults: Diagnosis and Initial Management. AFP
Fellowship Notes
BSc, MD (UWA), MPH (UNSW). Emergency Physician in training. German translator and lover of medical history.
Educator, magister, munus exemplar, dicata in agro subitis medicina et discrimine cura | FFS |