Early postnatal point-of-care glucose screening in late preterm neonates of 35-36 weeks gestation

Abstract. Background: Late preterm (LPT) neonates have been shown to be at higher risk for hypoglycemia compared withterm neonates. Aims: To characterize postnatal values for point-of-care glucose (POCG) screening in late preterm neonates with a gestationalage of 35-36 weeks, to assess the impact of additional risk factors in the development of POCG values ≤45 mg/dL in LPTneonates, and to compare laboratory and POCG values. Study design: POCG values were determined during the first 12 hours of life, and percentile trend lines were determined. LPTneonates were assigned to one of two groups: (1) no additional risk factors for POCG values ≤45 mg/dL (≤2.5 mmol/L); (2) atleast one additional risk factor. Term neonates with pre-determined risk factors for hypoglycemia were screened at least once.Screening results were compared with laboratory determinations if the samples were obtained within 8 minutes of each other. Subjects: 238 LPT neonates with a gestational age of 35-36 weeks admitted to a newborn nursery. Outcome measures: POCG values and laboratory glucose values related to postnatal age; associated risk factors for POCGvalues were ≤45 mg/dL. Results: Minimum and 10th percentile values during the study period ranged from 20–48 mg/dL (1.1–2.7 mmol/L) and36–59 mg/dL (2.0–2.3 mmol/L), respectively. No significant differences in incidence or distribution of POCG values ≤45 mg/dLwere noted between the two groups. Values ≤45 mg/dL were noted frequently following an initial value >45 mg/dL. POCGvalues tended to be higher than laboratory glucose values, particularly in the lower range. The incidence of hypoglycemia inLPT infants was similar to the incidence in full-term infants with risk factors. Conclusions: Given the tendency for POCG to over-estimate laboratory glucose, the actual incidence of hypoglycemia in thiscohort may be higher than we have reported. All neonates with gestational age 35-36 weeks should be monitored closely forhypoglycemia; a single screening value after delivery is inadequate.