- A rare but potentially lethal complication associated with the relief of (most commonly, chronic) urinary obstruction
- May result in dehydration, electrolyte imbalances, and death if not adequately treated
- Polyuria after relief of urinary tract obstruction (frequently Foley catheter placement)
- Some patients may experience hematuria, which is rarely clinically significant 
- Osmotic diuresis
- Drugs: diuretics, caffeine, acetazolamide, lithium
- Diabetes insipidus
- Cushing's syndrome, primary hyperaldosteronism
- Inability to concentrate urine (e.g. chronic pyelonephritis, sickle cell disease, amyloidosis
- Post-obstructive diuresis
- Early renal failure
- High fluid intake
- Excess IVF
- Psychogenic polydipsia
- Urine is usually hypotonic with large amounts of sodium chloride, potassium, phosphate and magnesium 
- Urine Output > 125 - 200mL/hour after relief of obstruction for at least 3 consecutive hours
- Urine Osmolarity > 250mosm/kg 
- Fluid replacement with care not to perpetuate diuresis
- IV vs. PO replacement is institution and patient specific
- Halbgewachs C, Domes T. Postobstructive diuresis. Can Fam Physician. 2015 Feb; 61(2): 137–142.
- Nyman MA et al. Management of urinary retention: rapid versus gradual decompression and risk of complications. Mayo Clin Proc. 1997;72(10):951
- Jameson et al. Harrison's Principles of Internal Medicine 20th edition. Chapter 313.
- Nyman et al. Management of Urinary Retention: Rapid Versus Gradual Decompression and Risk of Complications. Mayo clinic proceedings. 1997;72:951-956.
- Reynard et al. Oxford Handbook of Urology. Chapter 4. 2005. Oxford University Press.