Why Correct Sodium for Glucose?
High blood glucose draws water from cells into blood vessels (osmotic effect), diluting sodium. Measured sodium appears falsely low (pseudohyponatremia). Correcting sodium accounts for this dilutional effect, revealing true sodium status.
When to Correct
Correct when glucose >150 mg/dL, especially in diabetic ketoacidosis (DKA) or hyperosmolar hyperglycemic state (HHS). For every 100 mg/dL glucose above normal (100 mg/dL), add 1.6 mEq/L to measured sodium. Some sources use 2.4 mEq/L for glucose >400 mg/dL.
Clinical Implications
A patient with measured Na 130 and glucose 500 actually has normal or high sodium once corrected. As glucose is treated and decreases, measured sodium will rise. Failure to recognize this can lead to inappropriate treatment and complications. Always correct sodium in hyperglycemic states before diagnosing hyponatremia.
Quick Tips
- BMI alone doesn't reflect overall health
- TDEE varies based on activity level
- Consult a healthcare professional for medical decisions
Frequently Asked Questions
When glucose is >150 mg/dL, especially in DKA or HHS.
Yes, measured sodium will increase as glucose normalizes and water redistributes.
Usually no. Treat the hyperglycemia; sodium will normalize as glucose decreases.
Then true hyponatremia exists and needs evaluation/treatment separate from hyperglycemia.
Related but different. Corrected sodium assesses true sodium status; osmolality measures all solutes.