Blood Glucose Measurements in Newborns With Hypoglycemia

Source: Frymoyer A, Monasch EM, Lee MY, et al. Burden of 'pokes' in newborns with hypoglycemia who require IV dextrose. Hosp Pediatr. 2025;15(8):e377-e381; doi: 10.1542/hpeds.2025-008375.Investigators from Stanford University, Palo Alto, CA, conducted a retrospective study to describe the burden of heel lances ('pokes') for blood glucose (BG) measurement in neonates admitted to the newborn nursery who were at risk for hypoglycemia. The main analysis focused on newborns who required transfer to the NICU for intravenous (IV) dextrose to achieve and maintain euglycemia. For the study, the authors reviewed a data set collected for a quality control project on hypoglycemia at a university-affiliated children’s hospital with approximately 4,500 annual deliveries. Participants were newborns born at ≥35 weeks’ gestation between July 2018 and July 2024 who had 1 or more risk factors for hypoglycemia, including small for gestational age (SGA), large for gestational age (LGA), infant of a diabetic mother (IDM), or late preterm birth (<37 weeks’ gestation). These infants typically were screened using a point of care glucometer on blood obtained via a heel poke shortly after birth and, subsequently, prior to feeds until the BG was ≥45 mg/dL for 3 consecutive measurements. Hypoglycemia was treated initially with buccal dextrose gel and supplemental feedings. If the infant remained hyploglycemic after 3 doses of dextrose gel, they were transferred to the NICU for IV dextrose, and BG measurements continued via a heel poke. The primary outcome was the number of heel pokes in newborns requiring IV dextrose. The characteristics of these patients were compared to those in the data set who did not require IV dextrose.Data were analyzed on 7,823 newborns at risk for hypoglycemia; 298 (3.8%) required NICU transfer for IV dextrose. Among these 298 patients, the median number of heel pokes for BG measurement was 29 (interquartile range [IQR], 19–40). For at-risk newborns who did not require IV dextrose treatment, the median number of heel pokes was 5 (IQR, 4–6). Compared to at-risk patients not requiring IV dextrose, those requiring this treatment were significantly more likely to be late preterm (30.5% vs 18.6%; P <0.001), SGA (17.5% vs 12.4%; P = 0.01), and IDM (21.1% vs 14.6%; P = 0.003), and significantly less likely to be LGA (11.4% vs 20.1%; P <0.001). The median length of stay for infants requiring IV dextrose was 6 days.The authors conclude that newborns requiring IV dextrose for treatment of hypoglycemia experienced a high burden of heel pokes for BG measurement.Dr Chang has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.Transitional hypoglycemia is a common occurrence in otherwise healthy newborns after birth. IDM, late preterm, SGA, and LGA infants are at higher risk for hypoglycemia and recommended to undergo routine BG screening.1 Newborns with persistent hypoglycemia despite feeding and/or glucose gel administration often are transferred to the NICU for further care, which can include initiation of IV dextrose. In the current single-center study, the relatively small number of newborns who received IV dextrose had a median of 24 more heel pokes compared to at-risk newborns, who did not receive IV dextrose. Due to limited available data from their quality improvement project, the authors could not ascertain whether any of the newborns who received IV dextrose had underlying conditions that might cause prolonged hypoglycemia beyond 24–48 hours after birth. For newborns with self-limiting hypoglycemia, the current study results call into question whether the high burden of BG checks could be reduced.One consideration is that the optimal BG threshold to define hypoglycemia, to initiate IV dextrose in asymptomatic newborns, and to target while receiving IV dextrose are all unclear. Thus, there is considerable variation in the thresholds used by nurseries across the United States, as well as in the duration of BG screening for at-risk newborns.2 Some have proposed different thresholds for different risk factors.3 A randomized controlled trial found that a BG threshold of 36 mg/dL was noninferior to a threshold of 47 mg/dL with regard to short-term, neurodevelopmental outcomes at 18 months of age. (See AAP Grand Rounds. 2020;43[5]:58.)4 Naturally, targeting a lower BG threshold, even in a subset of at-risk newborns, would lead to less need for IV dextrose, shorter duration of IV dextrose treatment (if initiated), and fewer heel pokes for BG measurements.Newborns with hypoglycemia who receive IV dextrose undergo a high number of blood glucose measurements.As pointed out in the commentary, the benefits of aggressively testing and treating a BG level that is defined as 'hypoglycemic,' are unclear. Perhaps there should be more focus on the risk of transfer of otherwise healthy newborns to the NICU for treatment for IV glucose, such as separation from the mother, with possible impact on initiation of breastfeeding.