How is overflow incontinence best managed?

Management of Overflow Incontinence

Overflow incontinence is best managed by addressing the underlying cause of urinary retention and implementing catheterization when necessary, with pharmacological therapy targeted at the specific etiology.

Understanding Overflow Incontinence

Overflow incontinence occurs when the bladder becomes overdistended and cannot empty properly, resulting in involuntary leakage of urine. It is characterized by:

• Frequent small-volume leakage
• Sensation of incomplete bladder emptying
• Hesitancy and weak urinary stream
• Post-void residual urine volume typically >300 mL

Diagnostic Approach

1. Identify the cause of urinary retention:

   • Bladder outlet obstruction (e.g., BPH in men)
   • Detrusor underactivity/acontractility
   • Neurological disorders affecting bladder function
   • Medication side effects

2. Essential assessments:

   • Post-void residual (PVR) measurement via ultrasound
   • Uroflowmetry to assess flow pattern and rate
   • Assessment of bladder sensation and contractility

Management Algorithm

Step 1: Address Reversible Causes

• Review and adjust medications that may contribute to urinary retention:
  • Anticholinergics
  • Opioids
  • Alpha-adrenergic agonists
  • Calcium channel blockers

Step 2: Cause-Specific Management

For Bladder Outlet Obstruction (BOO):

• α-adrenergic antagonists (α-blockers) are first-line therapy for BOO-related overflow incontinence 1, 2

  • Examples: tamsulosin, alfuzosin, doxazosin
  • Mechanism: Relax smooth muscle at bladder neck and prostate
  • Timeframe: Assess efficacy after 2-4 weeks

• 5α-reductase inhibitors for men with enlarged prostates (PSA ≥1.5 ng/mL) 1, 2

  • Examples: finasteride, dutasteride
  • Mechanism: Reduce prostate size
  • Timeframe: Requires at least 3 months for clinical effect

• Surgical intervention when pharmacotherapy fails:

  • Transurethral resection of prostate (TURP) for men with BOO 1
  • Consider when Qmax <10 mL/second

For Detrusor Underactivity:

• Optimize bladder emptying through timed voiding schedule 1

  • Regular moderate drinking and voiding regimen
  • Double voiding technique (multiple toilet visits in close succession)
  • Proper voiding posture to facilitate pelvic floor relaxation

• Catheterization options:

  • Clean intermittent catheterization (CIC) is first-line for neurogenic bladder 2
  • Frequency determined by post-void residual volumes
  • Indwelling catheter only when other methods fail

Step 3: Adjunctive Measures

• Manage concurrent bowel dysfunction as it can worsen bladder symptoms 1
• Consider antibiotic prophylaxis for recurrent UTIs until symptoms improve 1
• For elderly patients with faecal impaction causing overflow:
  • Clinical assessment rather than marker studies is recommended 1
  • Address constipation and implement bowel management program

Special Considerations

Frail and Elderly Patients

• Use caution with medications due to increased risk of adverse effects 1
• Prompted voiding and fluid management may be more appropriate than pharmacotherapy 1
• Assess for and address faecal impaction, which can present with overflow incontinence 1

Monitoring and Follow-up

• Regular assessment of post-void residual volumes
• Uroflowmetry to evaluate treatment response
• Annual follow-up to detect symptom progression 1

Common Pitfalls to Avoid

1. Misdiagnosis as urgency incontinence - overflow can present with frequency and urgency
2. Treating with anticholinergics - these can worsen overflow incontinence
3. Inadequate follow-up - retention can lead to upper tract damage if not monitored
4. Failure to address concurrent conditions - particularly constipation and medication side effects

By systematically addressing the underlying cause of urinary retention and implementing appropriate bladder emptying strategies, overflow incontinence can be effectively managed in most patients.