How to manage urinary retention in a 68-year-old male with ultrasonography (USG) showing a distended urinary bladder, normal wall thickness, significant post-void residual volume, and a normal-sized prostate?

Management of Urinary Retention in a 68-Year-Old Male with Significant Post-Void Residual Volume

Alpha-adrenergic blockers (α-blockers) are the first-line pharmacological treatment for this patient with significant post-void residual volume (PVR) of 80ml after voiding 200ml, despite having a normal-sized prostate (21cc). 1

Initial Assessment and Diagnosis

The patient presents with:

• 68-year-old male
• Pre-void bladder volume: 200ml
• Post-void residual: 80ml (significant)
• Normal prostate size (21cc)
• No evidence of calculi or abnormal bladder wall thickness

This represents a case of urinary retention with significant post-void residual volume. While the patient's prostate is normal in size, the significant PVR indicates bladder emptying dysfunction that requires management.

Management Algorithm

Step 1: Behavioral and Lifestyle Interventions

• Implement regular voiding schedules (every 2-3 hours during waking hours)
• Teach double voiding technique (voiding, waiting a few minutes, then attempting to void again)
• Ensure proper toilet posture with buttock support, foot support, and comfortable hip abduction 1
• Address any constipation, which often coexists with voiding dysfunction 1
• Recommend adequate fluid intake of 2-3L per day, with reduced intake in evening hours 2, 1

Step 2: Pharmacological Management

• Initiate alpha-adrenergic blockers (α-blockers) as first-line therapy 1, 3

  • Options include tamsulosin 0.4mg daily, alfuzosin 10mg daily, or doxazosin 4-8mg daily
  • These medications relax smooth muscle at the bladder neck and throughout the urethra, decreasing outlet resistance 1, 3
  • Alpha blockers have shown to improve maximum urinary flow rate by 1.0-1.9 mL/sec compared to placebo 3

• Monitor for side effects including orthostatic hypotension, dizziness, and retrograde ejaculation

Step 3: Follow-up and Monitoring

• Schedule follow-up within 4-12 weeks after initiating treatment 1
• Reassess symptoms and perform post-void residual measurement 1
• If PVR remains >180ml, consider additional interventions as this threshold is associated with increased risk of bacteriuria (87% positive predictive value) 4

Step 4: Additional Interventions if Initial Treatment Fails

• Consider urodynamic studies to further evaluate bladder function
• If detrusor underactivity is suspected, consider adding bethanechol
• For patients with persistent significant PVR, intermittent catheterization may be necessary 2
  • Intermittent catheterization should occur every 4-6 hours to prevent filling beyond 500ml 2
  • This helps retrain the bladder and stimulate normal physiological filling and emptying

Special Considerations

Medication Review

• Review and consider discontinuing medications that may contribute to urinary retention 5:
  • Anticholinergics
  • Opioids
  • Benzodiazepines
  • NSAIDs
  • Calcium channel blockers

Monitoring for Complications

• Watch for signs of urinary tract infection, which occurs in 15-60% of patients with urinary retention 2
• Monitor for upper tract changes with periodic ultrasound if retention persists

Pitfalls and Caveats

1. Don't assume prostate enlargement is the only cause of urinary retention in older men

   • This patient has normal prostate size (21cc), suggesting other factors are contributing to his retention

2. Don't delay treatment of significant PVR

   • PVR >180ml significantly increases risk of bacteriuria even in asymptomatic patients 4

3. Don't overlook detrusor underactivity as a cause

   • In older patients, impaired detrusor contractility may contribute to retention even with normal prostate size 2

4. Avoid indwelling catheters when possible

   • Indwelling catheters should be avoided if possible due to increased risk of UTI and should be removed as soon as the patient is stable 2

5. Don't rely on a single PVR measurement

   • PVR measurements should be confirmed with a second measurement at another visit due to significant intra-individual variability 1

By following this structured approach, the patient's urinary retention can be effectively managed with the goal of improving bladder emptying, preventing complications, and enhancing quality of life.