Sodium Correction Calculator
Hyponatraemia & hypernatraemia in dogs and cats — with glucose correction, free-water deficit and safe-rate limits
Which patient are you treating?
Species sets the reference range; weight sets total body water. The unit applies to the blood glucose value.
What did the bloods show?
Measured sodium is required. Glucose is optional.
mmol/L (as reported by lab)
Used to correct Na⁺ for hyperglycaemia (translocational effect)
What is the clinical picture?
Onset sets the safe 24 h ceiling, and the two flags add a check before treating.
Default 0.6. Use ~0.7–0.8 for neonates/paediatrics; ~0.5 for obese/geriatric.
Which fluid, over how long?
For the rate estimate — these three are read together.
Adrogué–Madias uses the fluid's Na⁺ + K⁺ content to predict ΔNa per litre.
hours to reach the 24 h safe target
mmol/L — leave blank to auto-calc
Here is the assessment and plan
The assessment recalculates live as you type.
Your assessment will appear here
Enter a body weight and a measured serum Na⁺ to generate the assessment and, where sodium is out of range, the correction plan. Everything else is optional.
Clinical use & safety. This calculator is a bedside estimation aid for qualified veterinary professionals. Every formula here — including Adrogué–Madias — assumes a closed system and ignores ongoing losses, insensible losses and maintenance requirements. Recheck serum Na⁺ every 2–4 hours and adjust to the measured trend. Figures are guidance only and do not replace clinical judgement or current species-specific references.
Fluid sodium reference & formulas
| Fluid | Na⁺ (mmol/L) | K⁺ (mmol/L) | Typical use |
|---|
- Glucose-corrected Na⁺ = measured Na⁺ + 1.6 × [(glucose − 5.5) ÷ 5.6] (glucose in mmol/L; ≈1.6 mmol/L Na⁺ per 100 mg/dL glucose above normal)
- Total body water (TBW) = weight (kg) × fraction (default 0.6) → litres
- Free water deficit = TBW × [(current Na⁺ ÷ normal Na⁺) − 1] (hypernatraemia)
- Sodium deficit = TBW × (target Na⁺ − current Na⁺) (hyponatraemia)
- Adrogué–Madias — ΔNa⁺ per 1 L infusate = (infusate Na⁺ + infusate K⁺ − serum Na⁺) ÷ (TBW + 1)
