Calculator Inputs
The page stays single-column overall, while the calculator fields adapt to large, medium, and mobile screens.
Example Data Table
| Scenario | Weight | Gestation | Day | Modifiers | Adjusted Rate | Daily Volume | Hourly Rate | GIR |
|---|---|---|---|---|---|---|---|---|
| Term infant under phototherapy | 3.10 kg | Term | 3 | Phototherapy | 110 mL/kg/day | 341 mL/day | 14.21 mL/hr | 7.64 mg/kg/min with D10 |
| Late preterm infant on warmer | 2.40 kg | 33–36 weeks | 2 | Radiant warmer | 115 mL/kg/day | 276 mL/day | 11.50 mL/hr | 7.99 mg/kg/min with D10 |
| Very preterm infant in humidified incubator | 1.10 kg | ≤32 weeks | 4 | Humidified incubator | 137.8 mL/kg/day | 151.6 mL/day | 6.32 mL/hr | 5.75 mg/kg/min with D10 |
Formula Used
1) Baseline maintenance rate: choose a starting value in mL/kg/day from the gestation group and day-of-life table.
2) Modifier percentage: add or subtract environmental and therapy adjustments, then include any custom percentage change.
3) Adjusted rate: Adjusted mL/kg/day = Baseline × (1 + Modifier% ÷ 100)
4) Total daily volume: Daily mL/day = Adjusted mL/kg/day × Current weight in kg
5) Hourly rate: mL/hr = Daily mL/day ÷ 24
6) Glucose infusion rate: GIR = (Dextrose mg/mL × mL/hr) ÷ (Weight × 60), where Dextrose mg/mL = Dextrose % × 10.
7) Electrolyte estimate: Daily mmol = Target mmol/kg/day × Weight in kg. Early electrolyte therapy should always follow local guidance and labs.
How to Use This Calculator
- Enter the infant’s current weight. Add birth weight if you want the tool to show weight change from birth.
- Select the gestation group and day of life. For days above seven, the calculator keeps the day 7 baseline.
- Add temperature, dextrose concentration, and optional electrolyte goals. Then tick clinical modifiers that match the current setting.
- Use the custom adjustment field for protocol-specific changes or consultant-directed increases and reductions.
- Press the calculate button. The result appears above the form under the page header.
- Review the daily volume, hourly rate, feed-equivalent volume, GIR, and notes before prescribing.
- Use the CSV or PDF buttons to save the result for rounds, chart review, or handover.
FAQs
1) What does this calculator estimate?
It estimates neonatal maintenance fluid needs using weight, day of life, gestation, and common bedside modifiers. It also converts the total into hourly and interval-based delivery amounts.
2) Does it replace a neonatal unit protocol?
No. It is a structured calculation aid. Final prescriptions should follow unit policy, consultant guidance, lab data, urine output, weight trend, and the infant’s clinical condition.
3) Why does gestation group matter?
More premature infants usually have greater insensible losses and different early fluid needs. The gestation choice changes the baseline starting range before modifiers are applied.
4) Why are day 1 and day 2 values lower?
Early neonatal fluids often begin lower and increase over the first several days while transitional physiology, urine output, and expected postnatal weight loss are observed.
5) What is GIR and why is it shown?
GIR means glucose infusion rate. It helps you check whether the selected dextrose concentration and hourly fluid rate provide an appropriate glucose delivery level.
6) When should I use the custom adjustment field?
Use it when your team wants an extra percentage increase or decrease beyond the preset modifiers, such as unusual insensible losses or unit-specific practice changes.
7) Are sodium and potassium values automatic prescriptions?
No. They are simple daily estimates from the targets you enter. Neonatal electrolyte therapy must be individualized, especially in the first 48 hours or during instability.
8) Why does the calculator show review notes?
The notes highlight situations that may deserve extra checking, such as high fluid rates, major weight loss, low urine output, or glucose delivery outside a common target range.