How to Use Maintenance Fluid Calculator
Maintenance Fluid Calculator is built to estimate daily maintenance fluid needs, dehydration deficit, and a practical electrolyte review note from weight and clinical condition. Focus first on the inputs that directly drive the calculation:
- Enter the core measurement — Enter weight in kilograms. This is the base driver of maintenance fluid.
- Check units and options — Enter dehydration percent if a deficit estimate is needed; use 0 when only maintenance fluid is being reviewed.
- Read the primary result — Choose the clinical situation to apply a standard, fever, restricted, or high-loss adjustment.
- Review supporting values — Choose mL or L for the displayed primary result, then copy the summary if needed.
Formula & Theory - Maintenance Fluid Calculator
Maintenance Fluid Calculator uses this core formula:
maintenance_low_ml_day = weight_kg × 30 × condition_factor
maintenance_high_ml_day = weight_kg × 35 × condition_factor
deficit_ml = weight_kg × dehydration_percent × 10
daily_fluid_ml ≈ average(maintenance_low, maintenance_high) + deficit_mlThe Maintenance Fluid Calculator uses the adult-style 30-35 mL/kg/day estimate requested for this tool and then applies a small clinical multiplier. Dehydration deficit is added separately so users can see the difference between baseline maintenance and replacement need.
Electrolytes are not calculated as a fixed prescription because sodium, potassium, chloride, renal function, ongoing losses, and serum values must be individualized. The result therefore prompts electrolyte review rather than pretending one ratio fits every case.
Before interpreting Maintenance Fluid Calculator, confirm the dehydration percentage and clinical situation are assumptions you actually intend to model.
Use Cases for Maintenance Fluid Calculator
Maintenance Fluid Calculator is most useful in these situations:
- Teaching daily maintenance fluid arithmetic.
- Checking how dehydration percent changes total fluid.
- Comparing standard and restricted-fluid assumptions.
- Copying a quick fluid estimate into a draft note for review.