Clinical Pearls & Morning Reports
van Kempen et al. conducted a randomized trial that compared two accepted threshold glucose values for treatment of asymptomatic moderate hypoglycemia (defined as plasma glucose concentrations of 36 to 46 mg per deciliter [2.0 to 2.5 mmol per liter]) in four high-risk subgroups of otherwise healthy newborns. Read the NEJM Original Article here.
A: Because neonatal hypoglycemia often is asymptomatic, up to 30% of all newborns are presently routinely monitored for hypoglycemia for 12 to 36 hours after birth when current guidelines are followed. However, there is no consensus regarding the threshold glucose concentration at which treatment for asymptomatic neonatal hypoglycemia should be initiated.
A: Newborns found to have asymptomatic moderate hypoglycemia between 3 and 24 hours after birth were randomly assigned in a 1:1 ratio to receive treatment when the glucose concentration was lower than 36 mg per deciliter (lower-threshold group) or to receive treatment when the glucose concentration was lower than 47 mg per deciliter (traditional-threshold group).
A: In the trial by van Kempen et al. involving otherwise healthy newborns born at 35 weeks of gestation or later and weighing 2000 g or more, a management strategy that used a lower glucose threshold value to start treatment for asymptomatic moderate hypoglycemia did not lead to worse psychomotor development at 18 months than a strategy that used a traditional (higher) threshold. In fact, allowing glucose concentrations of 36 mg per deciliter or higher in the first 48 hours after birth was associated with developmental outcomes that were similar to those observed when glucose concentrations of 47 mg per deciliter or higher were targeted. Furthermore, there were fewer diagnostic interventions, including 9% fewer glucose measurements, and fewer therapeutic interventions in the lower-threshold group than in the traditional-threshold group.
A: The authors point out that their conclusions should not be extrapolated to hypoglycemia that persists after the first 2 postnatal days or to newborns who are born at less than 35 weeks of gestation, have a birth weight of less than 2000 g, or are sick. Such infants are already at an increased risk for impaired developmental outcome, which makes a lower treatment threshold less desirable. In addition, they emphasize the need for a higher target glucose concentration in newborns who have persistent hypoglycemia due to endocrine or metabolic disorders.