TBW × (Na/140 − 1).
mmol/L
kg
Patient group
Free water deficit
6.0 L
Formula
weight * tbwFactor * (na / 140 - 1)
Notes
Add ongoing losses. In chronic hypernatraemia lower Na by ≤ 10-12 mmol/L per 24 h.References
Used in
Calculators support, not replace, clinical judgement. Check inputs and units, and confirm doses with your unit protocol.