Hyponatremic encephalopathy is a true emergency and due to hypoosmolar-induced cerebral edema.
In contrast to the asymptomatic patient with hyponatremia, treatment of hyponatremic encephalopathy is determined by symptoms and not the duration of hyponatremia.
Clinical manifestations include nausea, vomiting, headache, confusion, seizures, respiratory failure, and coma.
Hypertonic saliine is the treatment of choice
Administer 2 ml/kg 3% hypertonic saline (100 ml in many cases)
This will typically raise serum sodium 2 mEq/L
In most cases, a 4-6 mEq/L rise will reverse neurologic symptoms
References
Archinger SG, Ayus JC. Treatment of hyponatremic encephalopathy in the critically ill. Crit Care Med. 2017; epub ahead of print.
