Glucose derangement, particularly hypoglycemia, is very common in the newborn. The definition of hypoglycemia is nebulous even after much discussion and some research over the last 15 to 20 years.
Cornblath and colleagues1 discuss this, and it is also acknowledged by the statement on Postnatal Glucose Homeostasis by the American Academy of Pediatrics.2 This statement was reaffirmed in 2015 and remains unchanged. It states “Blood glucose concentrations as low as 30 mg/dL are common in healthy neonates by 1 to 2 hours after birth.”2
Due to the common occurrence of what many recognize as a low blood glucose number and the lack of any evidence to support that this is harmful in newborns, routine screening of all infants is not indicated.2 So, the guideline applies to infants who are considered at risk for hypoglycemia, specifically the late preterm infant, term small for gestational age infant, and infants of diabetic mothers or large for gestational age infants.
For these infants, treating the low glucose value is recommended at different levels, whether or not the infant is symptomatic. If the infant is not symptomatic, treatment may be started with a blood glucose as low as 25 mg/dL or less. This very low level of glucose makes a lot of practitioners nervous!
Glucose and the brain
While there is little to no evidence that these low blood glucose levels lead to poor neurologic outcome, we do know that glucose is the major nutrient used by the brain. However, it is also known that infants are able to use alternate energy during this time, specifically ketone bodies released from the metabolism of fat.
It is also known that breastfed infants often have a lower glucose level than those fed formula, particularly in the first day or two after delivery. 3, 4 These infants also have a higher level of ketone bodies available, which provides the necessary energy during this period.2
However, a recently published prospective cohort trial shows that while there was no evidence of combined neurosensory impairment at 4.5 years as evaluated in this study, increased risk for poor executive function and visual motor function was found associated with lower or more frequent episodes of hypoglycemia.5 These differences in neurologic outcome may be more evident as children become older. Therefore, it may be prudent to provide treatment for hypoglycemia earlier, particularly in infants at high risk for hypoglycemia.
The AAP recommendations for treating hypoglycemia include a combination of intravenous glucose and feeding the infant.2 For those infants who are breastfed, treatment for hypoglycemia may result in feeding with either a gastric tube or bottle. With more and more effort toward supporting and encouraging exclusive breast milk diets for all infants, feeding by bottle is recognized as a risk factor to accomplishing long-term exclusive breastfeeding.6, 7, 8 In fact, the AAP also has a recommendation to support exclusive breastfeeding for the first 6 months of life.9
Mothers and families want what is best for their newborn infant, and if told by healthcare providers in so many words or by actions that the milk they are providing is not meeting the needs of their infant, they may choose to stop breastfeeding even though this period of assumed hypoglycemia may be very transient. Therefore, there has been a search for alternative methods to treat hypoglycemia effectively without increasing cost (transfer to the NICU), increasing risk (starting an IV) or interrupting the successful initiation of breastfeeding.
In the Sugar Babies Study,10 undertaken in New Zealand, infants were randomized to receive either 40% dextrose gel or placebo. Most of these infants were infants of diabetic mothers, and therefore at risk for hypoglycemia in the immediate postnatal period. These researchers found that the dextrose gel was effective in treating the clinical hypoglycemia in the majority of infants.
This treatment is easy to administer as it is given into the buccal mucosa, and does not require use of an artificial nipple or intravenous catheter. Since this is a quick and simple treatment for hypoglycemia and does not separate mother and baby or impinge on the establishment of adequate breastfeeding, it does not increase costs or delay discharge. This method of treating hypoglycemia is also the subject of a Cochrane review,11 although there are few studies available for review.
Nevertheless, the incidence of adverse events is very low, and differences between groups given the dextrose gel and placebo show some advantage to using this intervention. This intervention has been rolling into clinical practice in many hospitals over the last few years.
While we still don’t know at what number hypoglycemia should be treated, there are values that have become standard as to indicate treatment, and the least invasive and potentially harmful intervention should be used. In addition, the recommended 40% dextrose gel is a common treatment for hypoglycemia in adults and pediatrics, therefore likely available in most hospital pharmacies.
Bennet et al detail a performance improvement project undertaken in their hospital utilizing 40% dextrose gel as a treatment for hypoglycemia. Of note, administration of the gel to an infant may take some training, since it is given buccally and not via nipple, a common feeding mechanism with which nurses are familiar. These authors reported a 73% reduction in NICU admissions with an admitting diagnosis of hypoglycemia as a result of this project.12 In addition, the percentage of exclusive breastfeeding for infants with hypoglycemia was reported at 49% and for all other infants was reported at 58%. The authors hypothesize that the rate of exclusive breastfeeding in hypoglycemic infants prior to the project approached 0%.
We are often reminded that infants are not small adults or even small pediatric patients. Yet, this is one example where something done for so many years, and quite routinely in this population, actually has some significant benefit without adverse effects for hypoglycemic neonates. However, it is still important that any practice is studied appropriately before rolling into clinical practice.
- Cornblath M, Hawdon JM, Williams AF, et al.Controversies regarding definition of neonatal hypoglycemia: suggested operationalthresholds. Pediatrics. 2000;105(5):1141–1145
- Adamkin DH, Committee on Fetus and Newborn. Postnatal glucose homeostasis in late-preterm and term infants. Pediatrics. 2011;127(3):575-9. Reaffirmed June, 2015.
- Cornblath M, Ichord R. Hypoglycemia in theneonate. Semin Perinatol. 2000;24(2):136 –149
- Williams AF. Hypoglycaemia of the newborn:a review. Bull World Health Organ. 1997;75(3):261–290
- McKinlay CJ, Alsweiler JM, Anstice NS, Burakevych N, Chakraborty A, Chase JG, Gamble GD, Harris DL, Jacobs RJ, Jiang Y, Paudel N. Association of neonatal glycemia with neurodevelopmental outcomes at 4.5 Years. JAMA pediatrics. 2017 Oct 1;171(10):972-83.
- World Health Organization; United Nations Children’s Fund. Protecting, Promoting, and Supporting Breastfeeding: The Special Role of Maternity Services. Geneva, Switzerland: World Health Organization; 1989
- Philipp BL, Merewood A, Miller LW, et al. Baby-friendly hospital initiative improves breastfeeding initiation rates in a US hospital setting. Pediatrics. 2001;108(3):677–681pmid:11533335
- Murray EK, Ricketts S, Dellaport J. Hospital practices that increase breastfeeding duration: results from a population-based study. Birth. 2007;34(3):202–211pmid:17718870
- Eidelman AI, Schanler RJ, Johnston M, Landers S, Noble L, Szucs K, Viehmann L. Breastfeeding and the use of human milk. Pediatrics. 2012 Mar 1;129(3):e827-41.
- Harris DL, Weston PJ, Signal M, Chase JG, Harding JE. Dextrose gel for neonatal hypoglycaemia (the Sugar Babies Study): a randomised, double-blind, placebo-controlled trial. The Lancet. 2013 Dec 21;382(9910):2077-83.
- Hegarty JE, Harding JE, Crowther CA, Brown J, Alsweiler J. Oral dextrose gel to prevent hypoglycaemia in at-risk neonates. Cochrane Database of Systematic Reviews 2017, Issue 7. Art. No.: CD012152. DOI: 10.1002/14651858.CD012152.pub2.
- Bennett C, Fagan E, Chaharbakhshi E, Zamfirova I, Flicker J. Implementing a protocol using glucose gel to treat neonatal hypoglycemia. Nursing for women’s health. 2016 Feb 1;20(1):64-74.