From the Research
The best initial fluid choice for treating hypernatremia is hypotonic fluid, specifically 5% dextrose in water (D5W) or 0.45% sodium chloride (half-normal saline), as it provides free water without additional sodium, and this approach is supported by the most recent study 1. When treating hypernatremia, it is crucial to consider the underlying cause and the patient's overall clinical condition.
- For severe hypernatremia, 5% dextrose in water is preferred as it provides free water without additional sodium.
- The rate of correction should be gradual, typically aiming to decrease serum sodium by no more than 10 mEq/L in 24 hours (or 0.5 mEq/L per hour) to avoid cerebral edema and neurological complications, as highlighted in a case report 1.
- The specific volume needed can be calculated using the patient's water deficit, which considers the patient's weight and current sodium level.
- Ongoing losses should be replaced concurrently, and the underlying cause of hypernatremia must be addressed.
- Regular monitoring of serum sodium levels every 2-4 hours during initial treatment is essential to ensure appropriate correction rates.
- In patients with cardiac or renal dysfunction, careful monitoring of fluid status is necessary to prevent volume overload, as noted in a study on hypernatremia in diabetic ketoacidosis 2. This approach works because hypotonic fluids provide free water that dilutes the extracellular sodium concentration, gradually restoring normal osmolality while allowing the brain to readjust to changing serum osmolality, which is consistent with the findings of a study on the treatment of hypernatremia 3.