Normal Blood Glucose Range in Pediatric Population
In healthy children and adolescents beyond 72 hours of age, normal fasting blood glucose levels are 3.5-5.5 mmol/L, with random glucose values typically maintained between 3.9-7.8 mmol/L (70-140 mg/dL) approximately 96% of the time. 1, 2
Age-Specific Considerations
Immediate Newborn Period (First 72 Hours)
- In the first few hours after birth, blood glucose levels in healthy term neonates can range widely between 1.4-6.2 mmol/L 1
- By approximately 72 hours of age, fasting blood glucose levels stabilize to normal infant, child, and adult values of 3.5-5.5 mmol/L 1
- During fetal life, the normal lower limit is around 3 mmol/L 1
Infants and Young Children
- Significantly different glucose concentrations are observed in infancy, requiring age-specific partitioning: 0-<1 month, 1-<6 months, and 6 months-<19 years 3
- Random glucose measurements show age-dependent variations in the first 6 months of life 3
Children and Adolescents (Beyond Infancy)
- Mean average glucose: 5.4-5.5 mmol/L (98-99 mg/dL) for ages 6-60 years 2
- Time in normal range (3.9-7.8 mmol/L): 96% of the day (median) 2
- Coefficient of variation: 17 ± 3% (measure of glycemic variability) 2
Adults Over 60 Years
- Mean average glucose slightly higher at 5.8 mmol/L (104 mg/dL) 2
Critical Thresholds to Recognize
Hypoglycemia Definitions
- Newborns and neonates: Blood glucose <2.5 mmol/L (45 mg/dL) defines hypoglycemia requiring attention 4, 5
- Critically ill children: Hypoglycemia defined as <2.8 mmol/L (50 mg/dL) or <3.3 mmol/L (60 mg/dL) depending on the guideline 4, 5
- Repetitive or prolonged hypoglycemia ≤2.5 mmol/L should be avoided in all ICU patients due to potential adverse outcomes 4, 5
Hyperglycemia Definitions
- Neonatal ICU patients: Hyperglycemia >8 mmol/L (145 mg/dL) should be avoided as it is associated with increased morbidity and mortality 4, 6
- Preterm infants: Hyperglycemia commonly defined as >10 mmol/L (180 mg/dL) 4, 6
- Critically ill children: Definitions range from >7 mmol/L (126 mg/dL) to >8.3 mmol/L (150 mg/dL) 4
Normal Glucose Distribution in Healthy Children
Based on continuous glucose monitoring data in healthy, nondiabetic children 2:
- Median time >7.8 mmol/L (140 mg/dL): 2.1% of the day (approximately 30 minutes) 2
- Median time <3.9 mmol/L (70 mg/dL): 1.1% of the day (approximately 15 minutes) 2
- Interquartile range for time in 3.9-7.8 mmol/L: 93-98% 2
Important Clinical Caveats
Measurement Considerations
- Blood gas analyzers with glucose modules provide the best combination of quick results and accuracy for blood glucose measurements in newborns 5, 6
- Handheld glucose meters have limitations in neonates due to interference from high hemoglobin and bilirubin levels 5, 6, 7
- Point-of-care glucometers may be inaccurate in detecting neonatal hypoglycemia 7