The Use of Point of Care Testing in the Measurement of Blood Glucose Concentrations in Babies At-Risk of Neonatal Hypoglycaemia

Abstract

Neonatal hypoglycaemia is common and associated with neurodevelopmental impairment. Accurate measurement of blood glucose concentrations is important to identify hypoglycaemia. Non-glucose oxidase method point of care testing (POCT) devices are inaccurate when used to measure blood glucose concentrations in newborn babies. This retrospective, observational, multi-centre study investigated the prevalence of POCT use in the measurement of blood glucose concentrations in babies at-risk of neonatal hypoglycaemia at four Auckland maternity hospitals in New Zealand. POCT was the most common method of analysis used to measure blood glucose concentrations and inform the treatment of hypoglycaemia in newborn babies. Differences in clinical practice were found between the hospitals, North Shore and Waitakere Hospitals frequently confirmed low POCT results with an enzymatic result, while Auckland City and Middlemore Hospitals used POCT results to inform treatment of hypoglycaemia. A lower incidence of hypoglycaemia was found at Auckland City and Middlemore Hospitals. POCT results were found to significantly over and under-estimate blood glucose concentrations, when compared with samples analysed by enzymatic methods within 10 minutes of the POCT result. Treatment was delayed when samples analysed by enzymatic methods were used to inform the management of hypoglycaemia. Inaccurate blood glucose measurement is commonly used in clinical practice to screen for and inform treatment of neonatal hypoglycaemia in Auckland maternity hospitals. The incidence of hypoglycaemia was lower at the hospitals that used POCT more frequently, suggesting that babies who had episodes of hypoglycaemia may not have been identified, did not receive treatment, increasing the risk of long-term neurological impairment. However, it was not possible to adjust for the differences in characteristics or practices between the hospitals that may have affected the incidence of hypoglycaemia. A delay in treatment may lead to prolonged or recurrent hypoglycaemia which is associated with adverse neurological outcomes. To provide effective and efficient care to babies with hypoglycaemia, the introduction of portable devices that utilise enzymatic methods to measure blood glucose concentrations is recommended.