Disorders of sodium and water balance

Emerg Med Clin North Am. 2014 May;32(2):379-401. doi: 10.1016/j.emc.2014.01.001. Epub 2014 Mar 4.


Dysnatremias occur simultaneously with disorders in water balance. The first priority is to correct dehydration; once the patient is euvolemic, the sodium level can be reassessed. In unstable patients with hyponatremia, the clinician should rapidly administer hypertonic saline. In unstable patients with hypernatremia, the clinician should administer isotonic intravenous fluid. In stable patients with either hyponatremia or hypernatremia, the clinician should aim for correction over 24 to 48 hours, with the maximal change in serum sodium between 8 to 12 mEq/L over the first 24 hours. This rate of correction decreases the chances of cerebral edema or osmotic demyelination syndrome.

Keywords: Dysnatremia; Fluids for resuscitation; Hypernatremia; Hyponatremia; Water balance.

Publication types

  • Review

MeSH terms

  • Humans
  • Hypernatremia / metabolism*
  • Hyponatremia / metabolism*
  • Sodium / metabolism*
  • Water-Electrolyte Balance / physiology*


  • Sodium