The Total Body Water (TBW) calculator helps clinicians estimate changes in serum sodium concentration based on fluid administration and losses. This tool incorporates the patient's weight, sex, and fluid balance data to predict sodium concentration changes. It's particularly useful in managing fluid and electrolyte disorders and planning appropriate fluid therapy.
TBW = Weight × Sex Factor
Change in Na = [(Na+K)inf × Vinf - (Na+K)ur × Vur][TBW - Na(serum)]