What Is a Corrected Sodium for Hyperglycemia Calculator?
When blood glucose is significantly elevated, it draws water out of cells and into the bloodstream, diluting the sodium concentration a lab reports. That means a patient's measured sodium can look artificially low even when their true total-body sodium status is normal or high. This calculator applies the Katz correction factor to estimate what the sodium would read once the glucose returns to normal.
It's most useful in conditions with marked hyperglycemia, such as diabetic ketoacidosis (DKA) or hyperosmolar hyperglycemic state (HHS), where the dilutional effect can be large enough to change clinical decisions about fluids and electrolyte replacement.
How to Read Your Results
Corrected Sodium
The estimated sodium level once the dilutional effect of elevated glucose is accounted for — measured sodium plus the calculated correction.
Correction Applied
The amount added to (or, in the unusual case of low glucose, subtracted from) the measured sodium value.
Glucose Above Normal
How far the entered glucose sits above the 100 mg/dL reference point the correction factor is anchored to.
Real-World Example
A patient presenting in DKA has a measured sodium of 128 mEq/L and a glucose of 450 mg/dL.
| Metric | Value |
|---|---|
| Measured sodium | 128.0 mEq/L |
| Glucose | 450 mg/dL |
| Glucose above normal | +350 mg/dL |
| Correction | +5.6 mEq/L |
| Corrected sodium | 133.6 mEq/L |
The measured 128 mEq/L looks like hyponatremia at first glance, but once corrected for the markedly elevated glucose, the true sodium (133.6 mEq/L) is close to the normal range — a clinically important distinction for fluid management decisions.
Tips for Using This Calculator
- This calculator uses the classic Katz factor of 1.6. Some more recent studies suggest a factor closer to 2.4 may be more accurate at very high glucose levels, but 1.6 remains the standard taught and used in most clinical settings.
- Use sodium and glucose drawn from the same blood sample for an accurate correction.
- Corrected sodium is an estimate, not a substitute for trending repeat labs as glucose is treated and normalizes.
- Always interpret alongside the full clinical picture, including hydration status and other electrolytes.
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Last updated: August 2026 · Reviewed by: Simple Calculator Tools Editorial Team