**6. Laboratory diagnosis**

Glucometry is the method of choice for initial screening of glucose levels, due to its use and minimal blood sample required; however, levels should be confirmed through laboratory measurement in plasma, especially when the glucometer reading is very low, as this method is rather imprecise at the lower limit of detection. Several factors can affect the values obtained by glucometry, such as the expiration date of the test strip, ambient temperature and humidity in the storage environment, the presence of sugars other than glucose, metabolic acidosis, high PO2 , hyperbilirubinemia, high hematocrit, and edema, among others [25, 66]. Several devices have been tested with the aim of demonstrating that their results may be unreliable and influence the management indicated by a reading [14].

in the first hour of life, asymptomatic at-risk infants should have a glucose check 30 min after feeding; if the blood glucose level remains below 25 mg/dL and the infant is asymptomatic, it

Neonatal Hypoglycemia

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http://dx.doi.org/10.5772/intechopen.69676

Late-preterm, LGA, SGA, and intrauterine growth restriction (IUGR) infants, as well as those born to diabetic mothers, are at particular risk of hypoglycemia. However, they are often asymptomatic. Breastfeeding followed by repeated glucose measurement has been the standard of care. However, if hypoglycemia persists despite frequent feedings, continuous intrave-

A dextrose infusion rate of 3–5 mg/kg/min may be used in infants born to diabetic mothers, both to prevent overstimulation of glucose secretion and because of the greater fat mass of these infants. A dextrose infusion rate of 4–7 mg/kg/min may be used in most full-term and late-preterm neonates. In IUGR neonates, a glucose infusion rate of 6–8 mg/kg/min is often necessary. A study in an animal model of IUGR revealed increased peripheral insulin sensitivity, which may be associated with increased glucose infusion requirements. However, some children with IUGR should be followed closely, especially preterm infants, who may develop hyperglycemia due to reduced insulin secretion and less muscle mass for glucose utilization. Continuous intravenous glucose infusion, usually preceded by an IV bolus of dextrose (200 mg/kg over 5 min), is also indicated if these newborns develop symptomatic hypoglycemia. However, the need for such massive glucose administration is hotly contested due to the risk of undesirable effects, particularly in very-low-birth-weight preterm infants. Complete or partial resolution of symptoms once glucose concentration is corrected is considered definitive proof that symptoms were caused by hypoglycemia. Nevertheless, IV dextrose infusions are not an entirely appropriate treatment; they cause discomfort to the infant, which is made worse by the need for placement of a deep IV catheter, the need for NICU admission, and physical separation of the newborn from the mother, which hinders timely initiation of breastfeeding. However, when administered safely so as to prevent these complications, IV infusion of dextrose at low concentrations

Oral administration of glucose in gel form has been considered appropriate and should be part of any protocol to prevent episodes of hypoglycemia in asymptomatic newborns [41]. Current studies have shown that oral administration of 40% dextrose gel may reduce the occurrence of neonatal hypoglycemia by up to 70% [5] and should thus be considered as the

Symptomatic neonates should be treated with glucose intravenously, not orally. A 200 mg/kg bolus of glucose should be administered over 1 min (10% dextrose at 2 mL/kg). This should be followed by IV infusion at 6–8 mg/kg/min. Glucose levels should be monitored after 30–60 min,

should be fed again and blood glucose reassessed 1 h after the first check [67].

**8.2. Asymptomatic high-risk newborns**

nous infusion of glucose may be indicated.

can be beneficial even in asymptomatic high-risk neonates.

first-line treatment in these patients [65].

**8.3. Symptomatic newborns**

*8.2.1. Dextrose gel*

*8.3.1. Glucose*
