ADVICE
Hypernatremia is an elevation in serum sodium, indicating a free water deficit or dehydration.
In addition to calculating the free water deficit, the cause should be determined (e.g., loss of free water in the urine or stool, or lack of access to sufficient free water).
Patients may simultaneously be volume depleted and dehydrated. If this is suspected, correct the volume deficit with isotonic fluids first before correcting the water deficit calculated here.
Sufficient free water should be provided either orally or intravenously (using a solution such as 5% dextrose) to correct the serum sodium by up to 10 mEq/L in the first 24 hours.
