Sodium Correction (Hyperglycemia)

In severe hyperglycemia (e.g., DKA, HHS), excess glucose acts as an osmole, drawing free water out of the cells and diluting serum sodium. This causes a pseudohyponatremia. This calculator determines the true underlying sodium level using the Katz or Hillier equations.

Measured Sodium (mmol/L)

Measured Glucose (mmol/L)

Correction Factor

Hillier is often preferred for extremely high glucose levels (>22 mmol/L) as the osmotic effect is non-linear.

True Serum Sodium

mmol/L

Normal Sodium range is typically 135 - 145 mmol/L. This corrected value should guide fluid resuscitation choices (e.g., switching from 0.9% NaCl to 0.45% NaCl if corrected sodium is high).

Formulas (mmol/L)

Standard (Katz):
Measured Na +
1.6 × ((Glucose - 5.5) / 5.5)

Hillier:
Measured Na +
2.4 × ((Glucose - 5.5) / 5.5)

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