Risk Factors for Hypoglycemia
Neonates at increased risk for developing neonatal hypoglycemia should be routinely monitored for blood glucose levels irrespective of the mode of feeding. At risk neonates fall into two main categories:
- Excess use of glucose, which includes the hyperinsulinemic states
- Inadequate production or substrate delivery (Cornblath & Ichord, 2000)
The infant categories as shown in the Table below are at increased risk for hypoglycemia (Eidelman, 2001; Cornblath et al., 2000; Cornblath & Ichord, 2000; Cowett & Loughead, 2002; de Lonlay et al., 2004; Sunehag & Haymond, 2002).
Table. At-Risk Infants for Whom Routine Monitoring of Blood Glucose Is Indicated |
- Small for gestational age (SGA); <10th percentile for weight
- Large for gestational age (LGA); >90th percentile for weight*
- Discordant twin; weight 10% below larger twin
- Infant of diabetic mother, especially if poorly controlled
- Low birth weight (<2500 g)
- Perinatal stress; severe acidosis or hypoxia-ischemia
- Cold stress
- Polycythemia (venous hematocrit [Hct] >70%/hyperviscosity
- Erythroblastosis fetalis
- Beckwith-Wiedemann syndrome
- Microphallus or midline defect
- Suspected infection
- Respiratory distress
- Known or suspected inborn errors of metabolism or endocrine disorders
- Maternal drug treatment (e.g., terbutaline, propranolol, oral hypoglycemics)
- Infants displaying symptoms associated with hypoglycemia (see Table 3 in the original guideline document)
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*This remains controversial. Some recommend in unscreened populations in whom LGA may represent undiagnosed and untreated maternal diabetes.
From: Schaefer-Graf UM, Rossi R. Bührer C, et al. Rate and risk factors of hypoglycemia in large-for-gestational-age newborn infants of non-diabetic mothers. Am J Obstet Gynecol 2002;187:913–917; Cahill JB, Martin KL, Wagner CL, Hulsey TC. Incidence of hypoglycemia in term large for gestational age infants (LGA) as a function of feeding type. ABM News Views 2002;8:20.
General Management
Early and exclusive breastfeeding meets then nutritional and metabolic needs of healthy, term newborn infants. Healthy term infants do not develop symptomatic hypoglycemia simply as a result of underfeeding (Williams, 1997; Eidelman, 2001; Gartner et al., 2005).
- Routine supplementation of healthy, term infants with water, glucose water, or formula is unnecessary and may interfere with establishing normal breastfeeding and normal metabolic compensatory mechanisms (Hawdon, Ward Platt, & Aynsley-Green, 1992; Swenne et al., 1994; Gartner et al., 2005; National Childbirth Trust, 1997).
- Healthy term infants should initiate breastfeeding within 30 to 60 minutes of life and continue on demand, recognizing that crying is a very late sign of hunger (Gartner et al., 2005; WHO/UNICEF, 1989). Early breastfeeding is not precluded just because the infant meets the criteria for glucose monitoring.
- Initiation and establishment of breastfeeding is facilitated by skin-to-skin contact of mother and infant. Such practices will maintain normal infant body temperature and reduce energy expenditure (thus enabling maintenance of normal blood glucose) while stimulating suckling and milk production (Durand et al., 1997; Gartner et al., 2005).
- Feedings should be frequent, 10 to 12 times per 24 hours in the first few days after birth. (Gartner et al., 2005)
Glucose screening should be performed only on at-risk infants and those with clinical symptoms compatible with hypoglycemia.
- Routine monitoring of blood glucose in asymptomatic, term newborns is unnecessary and may be harmful (Williams, 1997; Eidelman, 2001; National Childbirth Trust, 1997; Nicholl, 2003; American Academy of Pediatrics [AAP] & American College of Obstetrics and Gynecology [ACOG], 2002).
- At-risk infants should be screened for hypoglycemia with a frequency and duration related to the specific risk factors of the individual infant (Eidelman, 2001). It is suggested that monitoring begin within 30 to 60 minutes for infants with suspected hyperinsulinemia, and no later than 2 hours of age for infants in other risk categories.
- Monitoring should continue, until normal, preprandial levels are consistently obtained.
- Bedside glucose screening tests must be confirmed by formal laboratory testing.
Management of Documented Hypoglycemia
Asymptomatic Infant
- Continue breastfeeding (approximately every 1 to 2 hours) or feed 3 to 5 mL/kg (up to 10 mL/kg) (Williams, 1997) of expressed breast milk or substitute nutrition (pasteurized donor human milk, elemental formulas, partially hydrolyzed formulas, routine formulas).
- Recheck blood glucose concentration before subsequent feedings until the value is acceptable and stable.
- If the neonate is unable to suck or feedings are not tolerated, avoid forced feedings (e.g., nasogastric tube) and begin intravenous (IV) therapy (see the following). Such an infant is not normal and requires a careful examination and evaluation in addition to more intensive therapy.
- If glucose remains low despite feedings, begin IV glucose therapy and adjust intravenous rate by blood glucose concentration.
- Breastfeeding may continue during IV glucose therapy when the infant is interested and will suckle. Wean IV glucose as serum glucose normalizes and feedings increase.
- Carefully document signs, physical examination, screening values, laboratory confirmation, treatment and changes in clinical condition (i.e., response to treatment).
Symptomatic Infants or Infants with Plasma Glucose Levels <20 to 25 mg/dL (<1.1 to 1.4 mmol/L)
- Initiate intravenous 10% glucose solution.
- Do not rely on oral or intragastric feeding to correct extreme or symptomatic hypoglycemia. Such an infant is not normal, and requires an immediate and careful examination and evaluation in addition to IV glucose therapy.
- The glucose concentration in symptomatic infants should be maintained >45 mg/dL (>2.5 mmol/L).
- Adjust intravenous rate by blood glucose concentration.
- Encourage frequent breastfeeding after the relief of symptoms.
- Monitor glucose concentrations before feedings as the IV is weaned, until values are stabilized off intravenous fluids.
- Carefully document signs, physical examination, screening values, laboratory confirmation, treatment, and changes in clinical condition (i.e., response to treatment).
Supporting the Mother
Having an infant who was thought to be normal and healthy and who develops hypoglycemia is both concerning to the mother and family, and may jeopardize breastfeeding. Mothers should be reassured that there is nothing wrong with their milk, and supplementation is usually temporary. Having the mother hand-express or pump milk that is then fed to her infant can overcome feelings of maternal inadequacy as well as help establish a full milk supply. It is important to provide stimulation to the breasts by manual or mechanical expression with appropriate frequency (eight times in 24 hours) until her baby is latching and suckling well to protect her milk supply. Keeping the infant at the breast, or returning the infant to the breast as soon as possible is important. Skin-to-skin care is easily done with an IV and may lessen the trauma of intervention, while also providing physiologic thermoregulation, contributing to metabolic homeostasis.