Newborns need a steady supply of glucose: a GIR of 4–6 mg/kg/min matches the liver’s glucose production in term babies. Higher rates may be needed for hypoglycaemia, while very high rates risk high blood sugar and liver fat.
How to use the GIR Calculator
- Dextrose concentration
- Infusion rate
- Weight
- Second infusion – dextrose
- Second infusion – rate
Results update as you type, and every field accepts the units shown in its menu.
How it works
Enter the dextrose concentration, infusion rate and weight; add a second infusion if there is one.
Inputs explained
| Field | What to enter |
|---|---|
| Dextrose concentration | In % |
| Infusion rate | In mL/h |
| Weight | Units: kg, lb, st, g |
| Second infusion – dextrose | In % |
| Second infusion – rate | In mL/h |
What each result means
- Glucose infusion rate = ([Dextrose concentration]×[Infusion rate] + [Second infusion – dextrose]×[Second infusion – rate])÷(6×[Weight])
- Glucose per day = [Glucose infusion rate]×[Weight]×1440÷1000
- Calories from glucose = [Glucose per day]×3.4
Example values
How the main result changes when Dextrose concentration changes and everything else stays at the example values above:
| Dextrose concentration (%) | Glucose infusion rate (mg/kg/min) |
|---|---|
| 5 | 2.4 |
| 7.5 | 3.6 |
| 10 | 4.8 |
| 12.5 | 6 |
| 15 | 7.1 |
| 20 | 9.5 |
Health note: this calculator is for education and screening only and is not a diagnosis or treatment advice. Discuss your results with a qualified clinician.
Formula
GIR (mg/kg/min) = dextrose % × rate (mL/h) × 10 ÷ (60 × weight kg)
= dextrose % × rate (mL/h) ÷ (6 × weight)
Worked example
Inputs — Dextrose concentration: 10 %; Infusion rate: 10 mL/h; Weight: 3.5 kg; Second infusion – dextrose: 0 %; Second infusion – rate: 0 mL/h.
Results — Glucose infusion rate = 4.8 mg/kg/min; Glucose per day = 24 g/day; Calories from glucose = 82 kcal/day.
Key terms
- GIR
- Glucose infusion rate.
Frequently asked questions
What is a normal GIR for a newborn?
About 4–6 mg/kg/min for term and 6–8 for preterm babies.
Why 3.4 kcal per gram?
Dextrose monohydrate in IV fluids provides 3.4 kcal/g.
What is the maximum dextrose in a peripheral line?
Usually 12.5%; higher concentrations need a central line.