ToolsCalculators
Body Fluid Balance by Inputs and Outputs
Net fluid balance from measured intake and output over a period.
Body Fluid Balance by Inputs and Outputs
IV fluids / medications
mL
Blood / colloid products
mL
Oral / enteral intake
mL
Urine output
mL
Drains / NG / emesis
mL
Stool / other losses
mL
Estimated insensible losses
mL
Complete the fields above to see the result.
When to use
- Tracking cumulative fluid balance in critically ill or perioperative patients.
Formula
Net balance = (IV fluids + blood/colloid + oral/enteral) − (urine + drains/NG/emesis + stool + insensible losses).
Pearls and pitfalls
- Cumulative positive fluid balance is associated with worse outcomes in critical illness.
- Insensible losses (~500–800 mL/day at rest) rise with fever and tachypnoea.