Sodium Correction Calculator

Hyponatraemia & hypernatraemia in dogs and cats — with glucose correction, free-water deficit and safe-rate limits
Clinical Tool

Patient & Values

kg
mmol/L (as reported by lab)
Used to correct Na⁺ for hyperglycaemia (translocational effect)

Clinical context

Chronic is the safe default — the brain has adapted, so correct slowly.
Default 0.6. Use ~0.7–0.8 for neonates/paediatrics; ~0.5 for obese/geriatric.

Fluid plan for rate estimate

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

Assessment & Plan

Waiting for input
Enter weight & Na⁺
Results update live as you type.
Fluid sodium reference & formulas
FluidNa⁺ (mmol/L)K⁺ (mmol/L)Typical use
Formulas used
  • 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)

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.

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