UMEM Educational Pearls

Hyponatremia in the Brain Injured Patient

  • Hyponatremia is the most common electrolyte disorder in neurocritical care and is associated with increased ICP.
  • The two most common causes of hyponatremia in this patient population are cerebral salt wasting syndrome and SIADH.
  • Symptomatic hyponatremia should be treated with hypertonic saline:
    • 30-45 ml of 10% NaCl or
    • 100-150 ml of 3% NaCl
  • In order to prevent osmotic demyelination syndrome (ODM), sodium should not be corrected by more than 10 mmol/L/day.
  • The risk of ODM is low when acute hyponatremia develops in less than 48 hours.

References

Mrozek S, et al. Pharmacotherapy of sodium disorders in neurocritical care. Curr Opin Crit Care. 2019; 25:132-7.