Back-to-Basics: Urinary Retention

EM Daily - Acute Urinary Retention 

Lynn Manganiello 

 

PEARLS: 

  • Dont mistake overflow incontinence as spontaneous voiding 

  • Consider other causes aside from BPH (although this is the most common cause) 

  • Must perform pelvic exam in female patients with urinary retention 

 

Pathophysiology of urine storage: 

  • Beta-adrenergic/anticholinergic - urine storage, relaxation of detrusor  

  • Alpha adrenergic - contraction of bladder neck and internal sphincter 

Pathophysiology of urination: 

  • Cholinergic - contraction of bladder detrusor 

  • Alpha-adrenergic inhibition - internal sphincter of bladder neck and urethras sphincter relaxation 

 

Differential diagnosis: 

Male-specific = BPH or prostate cancer, phimosis, paraphimosis, meatal stenosis, prostatitis 

Female-specific = obstruction from pelvic organ prolapse, ovarian or uterine tumor; incontinence surgery, PID 

 

Considerations for both males and females: 

  • Obstruction - stricture, bladder calculi or neoplasm, foreign body 

  • Neurogenic - Neuromusuclar disease, spinal cord compression, nerve injury from pelvic surgery 

  • Traumatic injury of urethra or bladder 

  • Extra-urinary - peri-rectal or pelvic abscess, rectal or retroperitoneal mass, fecal impaction, AAA, rectal prolapse 

  • Psychogenic - stress, anxiety 

  • Infectious - cystitis, HSV, zoster in pelvic region, local abscess 

  • Pharmacologic - anticholinergic, sympathomimetic agents, opioids, benzodiazepines, psychoactive agents, beta agonists, CCBs, decongestants, muscle relaxants, NSAIDs 

 

With the above differential in mind, be sure to ask: 

  • PMH and PSH 

  • Medication list  

  • Recent events or trauma 

  • Associated symptoms 

 

Physical Exam: 

  • GU/perineal exam 

  • Pelvic exam in female patients to detect possible pelvic or adnexal mass, pelvic organ prolapse 

 

Workup: 

-   Post-void residual is diagnostic 

  • UA - rule out infection 

  • Chemistry - renal function, electrolytes 

 

Management: 

-Treat underlying cause 

-Often requires placement of foley catheter 

-Follow up with urology in 3-7 days if appropriate for outpatient management 

-Add flomax if BPH is suspected cause 

-Admit if clot retention, sepsis, neurologic cause 

-Watch for excessive diuresis (>200cc/h of urine output over 2 hours) 

 

Special considerations: 

  • If recent urologic procedure > consult urology 

  • Clot retention > may need triple lumen foley (3-way” foley) for irrigation with saline until clear 

  • Post-op > typically only need straight cath without leaving foley in place, then voiding trial 

 

 

References:

  1. Billet, Michael, and Thomas Andrew Windsor. Urinary Retention.” Emergency Medicine Clinics of North America, vol. 37, no. 4, 2019, pp. 649660., doi:10.1016/j.emc.2019.07.005.  
  2. Yen, David Hung-Tsang and Chen-Hsen LeeAcute Urinary Retention. Tintinallis Emergency Medicine: A Comprehensive Study Guide, 8th Ed. Judith E. Tintinalli, et al. New York,  NY: McGraw-Hill, 2016.