Glucose Infusion Rate (GIR) Calculator

Glucose Infusion Rate Explained

The glucose infusion rate is a measure of the rate at which the patient receives intravenous administration of dextrose, which increases blood sugar levels. This is particularly useful in ensuring that a neonate’s blood glucose level remains at stable and normal levels. GIR is expressed in mg per kilogram body weight per minute.

Glucose infusion rate can be calculated through following equation:

• GIR = Infusion rate (mL/hr) x Dextrose concentration (g/dL) x 1000 (mg/g) / Weight (kg) x 60 (min/hr) x 100 (mL/dL)

The above can be simplified to:

• GIR = (Dextrose infusion rate x Dextrose concentration x 10) / (Weight in kg x 60)

If several dextrose solutions are used, GIR values are calculated for each, then the results are summed to provide the final GIR.

GIR for Neonates and Infants

In neonates and infants who are not feeding and require intravenous fluids, hypoglycaemia should be avoid by maintaining a GIR of 4-6 mg/kg/min.

Low glucose levels in neonates can result in neurological disorders. The management of neonatal hypoglycaemia depends upon the gestational age of the baby and the general health after delivery. Pediatric guidelines for the emergency management of hypoglycaemia include:

• D10W 5 mL/Kg (neonates);
• D25W 2 mL/kg (infants/children);
• D50W 1 mL/kg (adolescents).

Please note that continuous blood sugar levels outside the normal range despite correct GIR may be suggestive of abnormal glucose metabolism.

At the opposite end, higher GIRs are associated with hyperglycaemia, hepatic steatosis and cholestasis, therefore, GIR should not exceed:

• 11-13 mg/kg/min in under 1 year olds;
• 8-10 mg/kg/min in under 10 year olds;
• 5-6 mg/kg/min in over 10 year olds.

References

Guenst JM, Nelson LD. Predictors of total parenteral nutrition-induced lipogenesis. Chest. 1994; 105(2):553-559.

Solimano A. Drop that calculator! You can easily calculate the glucose infusion rate in your head, and should! Paediatrics & Child Health, Volume 25, Issue 4, June 2020, Pages 199–200.

Stensvold HJ, Lang AM, Strommen K, et al. Strictly controlled glucose infusion rates are associated with a reduced risk of hyperglycaemia in extremely low birth weight preterm infants. Acta Paediatr. 2018; 107(3):442-449.