Carolinas Core Concepts Core Concepts in EM; a repository for Carolinas lecture summaries.

14Sep/110

Hyponatremia

Nancy Gritter, MD
  • 100mmol of 3% NS will change serum sodium by about 2mmol/L.
  • Mortality of severe hyponatremia approaches 48% if left untreated due to cerebral edema; this outweighs the risk of central pontine myelinolysis. Indications for immediate correction are seizures, severe obtundation/coma, or focal neurologic findings.
  • Rule of 6's: if emergent, may correct up to 6mmol in the first 6 hours - but nobody should correct the sodium until the next day afterwards.  For safety, don't correct as an inpatient by more than 6 mmol in 24 hours.
    • Am J Kidney Dz 56;774-779, 2010
7Jul/110

Hyponatremia and SAH

  • 3% normal saline often corrects hyponatremia too quickly and may cause central pontine myelinolysis; reserve it for seizures, severe AMS, and coma.
  • Subarachnoid hemorrhage may still respond to compazine.  In the patient that refuses LP, consider CTA of the head to find small aneurysms.