UKMedCalc

For healthcare professionals. Educational tool only — not a medical device. Verify all results against the current BNF, NICE guidance and local policy, and apply clinical judgement.

NeonatalPaediatrics

Glucose Infusion Rate (GIR)

Calculates the glucose infusion rate in mg/kg/min from dextrose concentration and infusion rate — a core neonatal/paediatric TPN and fluid calculation.

kg
mL/h

Include all dextrose-containing fluids (feeds, drugs and flushes count towards total intake)

Enter the required values to see the result.

Formula

GIR (mg/kg/min)=% dextrose×rate (mL/h)6×weight (kg)\text{GIR (mg/kg/min)} = \frac{\% \text{ dextrose} \times \text{rate (mL/h)}}{6 \times \text{weight (kg)}}

Derived from: dextrose % × 10 = mg/mL; × rate = mg/h; ÷ weight ÷ 60 = mg/kg/min.

Caveats & limitations

  • Calculate GIR from the TOTAL dextrose intake — IV fluids, PN, drug infusions and flushes all contribute.
  • Targets vary with postnatal age, insulin use, and illness severity.
  • This tool computes a rate; it does not assess whether the fluid prescription itself is appropriate.

Evidence & UK guidance

Primary evidence

  • Standard pharmacokinetic arithmetic; see BNF for Children (intravenous fluid and neonatal parenteral nutrition guidance) and local neonatal unit protocols.

    Source

UK practice

Neonatal units typically start at 4–8 mg/kg/min and titrate to blood glucose; maximum tolerated is usually 10–12 mg/kg/min before hyperglycaemia or hepatic steatosis supervenes. Follow your unit's PN/fluid protocol and BNF for Children guidance.

Formula and citations last verified: 2026-08-03

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Predicts the change in serum sodium per litre of infusate and the infusion rate needed to achieve a safe correction target in hyponatraemia.

Schwartz eGFR

Estimates GFR in children aged 1–16 years from height and serum creatinine (revised 'bedside' Schwartz equation, 2009).