Hyperglycemia draws water from the intracellular to the extracellular space, diluting serum sodium. The corrected sodium estimates what the sodium would be if glucose were normal.
Formula
Corrected Na = Measured Na + 1.6 × [(Glucose − 100) / 100]
Glucose in mg/dL.
Clinical Use
- Diabetic ketoacidosis (DKA)
- Hyperosmolar hyperglycemic state (HHS)
- Severe hyperglycemia evaluation
Why It Matters
True hyponatremia in DKA changes management. If corrected sodium is normal or high, the apparent hyponatremia is dilutional and will resolve as glucose normalizes. The Hillier correction factor of 2.4 may be more accurate at very high glucose levels (>400 mg/dL).