About the GIR calculator (Glucose Infusion Rate)
Glucose infusion rate (GIR) measures how much dextrose a patient receives from an intravenous fluid, expressed as milligrams of glucose per kilogram of body weight per minute (mg/kg/min). It is the standard way clinicians describe carbohydrate delivery in neonatal and pediatric IV fluids and total parenteral nutrition (TPN), because it normalizes the dextrose concentration and infusion rate to a single figure that can be compared to target ranges regardless of the patient's size or the fluid recipe used.
The GIR formula
GIR is calculated from three inputs: the dextrose concentration of the IV fluid (as a percent, where D10W means 10 grams of dextrose per 100 mL), the infusion rate in milliliters per hour, and the patient's weight in kilograms:
GIR (mg/kg/min) = (Dextrose % x Rate in mL/hr x 10) / (Weight in kg x 60), which simplifies to (Dextrose % x Rate) / (Weight x 6).
The "x 10" converts a percent concentration (grams per 100 mL) into milligrams per mL, and dividing by 60 converts the hourly rate into a per-minute rate. If glucose is also being delivered from another line or an enteral source, its contribution in mg/kg/min can be added directly to the IV-fluid GIR, since GIR is additive across simultaneous glucose sources.
Putting the result in context
A commonly cited maintenance range for neonates is about 4-8 mg/kg/min, with many units starting near 4-6 mg/kg/min at birth and advancing gradually as glucose tolerance is confirmed with blood glucose checks. Growing preterm infants on parenteral nutrition often need higher sustained GIR, sometimes into the 10-12 mg/kg/min range, while sustained values above roughly 12-18 mg/kg/min are generally treated as a caution zone for hyperglycemia. These figures are general clinical reference points, not fixed rules — the appropriate target for any specific patient is set by the treating team based on gestational age, glucose levels, and clinical status.
When to consult a professional
This calculator performs the standard GIR arithmetic for planning and documentation. It does not replace clinical judgment, does not adjust for an individual patient's glucose tolerance, and should not be used to make dosing decisions on its own. Any change to IV fluids, dextrose concentration, or infusion rate should be ordered and verified by a licensed healthcare provider.