Glucose Infusion Rate (GIR) Calculator
What is Glucose Infusion Rate (GIR)?
The Glucose Infusion Rate (GIR) is a critical clinical measurement used primarily in neonatal and pediatric intensive care units. It represents the amount of glucose (sugar) a patient receives per kilogram of body weight per minute. Managing the GIR is essential for maintaining stable blood glucose levels in patients receiving Total Parenteral Nutrition (TPN) or intravenous fluids.
How to Calculate GIR Manually
While this calculator automates the process, understanding the formula is vital for clinical verification. The mathematical formula for GIR is:
The number 6 in the denominator is a constant derived from converting hours to minutes (60) and grams to milligrams (1000), while accounting for the percentage concentration.
Clinical Relevance and Normal Ranges
- Neonates: Starting GIR usually ranges between 4 to 8 mg/kg/min.
- Adjustment: In stable infants, the GIR may be increased gradually by 1-2 mg/kg/min per day, up to a maximum of 12-14 mg/kg/min, provided blood glucose remains within normal limits.
- Monitoring: High GIR can lead to hyperglycemia and hepatic steatosis, while low GIR can cause hypoglycemia, which is particularly dangerous for brain development in newborns.
Example Calculation
If a 2.5 kg neonate is receiving a 10% Dextrose solution at a rate of 5 mL/hr:
GIR = (5 mL/hr × 10%) / (2.5 kg × 6)
GIR = 50 / 15
GIR = 3.33 mg/kg/min
Disclaimer: This calculator is for educational purposes only and should not be used as the sole basis for clinical decisions. Always verify calculations manually in a medical setting.