Table 1

Commonly used definitions in hypoglycaemia. Definitions of thresholds such as mild and severe vary widely

Hypoglycaemic episodeOne or more measurements of glucose concentration below a defined operational threshold
Severe episodeLowest glucose concentration <2.0 mmol/L
Mild episodeLowest glucose concentration <2.6 mmol/L
Recurrent hypoglycaemia≥3 episodes
Transitional hypoglycaemiaLow concentrations of glucose caused by delayed metabolic transition after birth
Prolonged transitional hypoglycaemiaTransitional hypoglycaemia persisting beyond 72 hours after birth
Operational thresholdGlucose concentration when intervention is considered appropriate to minimise risk of brain injury
NeuroglycopeniaInadequate brain metabolic substrates for glycolysis