Calculate total sodium deficit for replacement planning.
Deficit (mEq) = TBW × (Target Na − Current Na). TBW = Weight × 0.6 (men) or 0.5 (women). Do NOT replace entire deficit rapidly. Correct ≤ 8–10 mEq/L per 24 hours. 3% saline contains 513 mEq/L. Use Adrogué-Madias for hour-by-hour planning.