Factors related to passing the safety fast test among neonates with hypoglycaemia in the neonatal intensive care unit

Aim: To investigate the success rates and predictors of safety fast test among neonates admitted to the neonatal intensive care unit for hypoglycaemia. Methods: A retrospective review of neonates transferred from the newborn nursery unit to the neonatal intensive care unit for intravenous dextrose therapy for hypoglycaemia from January 2016 to June 2019. Neonatal clinical and demographic variables were abstracted from the medical records. A successful safety fast test was defined by blood glucose >60 mg/dL (3.3 mmol/L) at 3, 4, 5 and 6 h after a feed. Results: Of the 76 neonates who had a safety fast test, 80% passed on their first attempt. Neonates who passed the safety fast test were less likely to be premature/small for gestational age (54.1% vs. 92.9%, P = 0.03), required less maximum glucose infusion rate (median 6 vs. 7 mg/kg/min; P = 0.04), and were younger at fasting challenge (median 5 vs. 9 days; P = 0.02), required lower overall intravenous glucose load (median 12 vs. 24 g/kg; P = 0.006). Conclusion: Safety fast test may be a useful tool evaluating discharge readiness of neonates with persistent hypoglycaemia.