The glycemic response of the newborn infant to epinephrine administration: a preliminary report

Advances in Understanding the Mechanism of Transitional Neonatal Hypoglycemia and Implications for Management

Our lack of basic knowledge about the basic mechanisms of transitional hypoglycemia and other forms of hypoglycemia in newborns underlies the ongoing controversies over standards for managing these conditions. To address this deficiency, the authors evaluated regulation of insulin secretion in fetal, newborn, and adult rats. The results demonstrate that transitional hypoglycemia in normal neonates and persistent hypoglycemia in high-risk infants both reflect altered beta-cell insulin regulation. These findings provide a new foundation for improving detection and management and preventing hypoglycemic brain injury in normal neonates and, especially, in infants with persistent hypoglycemia and genetic forms of congenital hyperinsulinism.

Low blood sugar levels in the newborn infant: Do changing goal posts matter?

Glucose supply and metabolism are essential for growth and normal brain development in both the fetus and newborn. Disorders of glucose availability and metabolism can result in either hypoglycemia or hyperglycemia. The first section of this manuscript will contrast recommendations from the American Academy of Pediatrics and the Pediatric Endocrine Society on the approach to defining neonatal hypoglycemia. Recent studies will be reviewed which add to the controversy. This review aims to discuss the evidence-based guidelines, definitions, pathogenesis, outcomes and management options in this field. The current variations in practices and possibilities of future trials are also addressed.

Neonatal hypoglycemia

A consistent definition for neonatal hypoglycemia in the first 48 h of life continues to elude us. Enhanced understanding of metabolic disturbances and genetic disorders that underlie alterations in postnatal glucose homeostasis has added useful information to understanding transitional hypoglycemia. This growth in knowledge still has not led to what we need to know: "How low is too low and for how long?" This article reviews the current state of understanding of neonatal hypoglycemia and how different approaches reach different "expert" opinions.

Neonatal hypoglycemia

PURPOSE OF REVIEW

The screening and management for neonatal hypoglycemia remains a confusing and contentious problem in neonatology. The purpose of this article is to contrast recent recommendations from the American Academy of Pediatrics and the Pediatric Endocrine Society.

RECENT FINDINGS

Using different methodologies, the organizations have significant differences on whom to screen and what levels of glucose should be used for management. The identification of the first 48 h as a transitional hyperinsulinemic state is a new important concept. The neuroendocrine approach is contrasted with a neurodevelopmental strategy to find levels that exceed those associated with neuroglycopenia.

SUMMARY

The questions remain the same when it comes to screening and management of neonatal low-glucose levels. Recent outcome studies with differing results continue to add to the controversy as to what to do at the bedside. It is uncertain if universal screening of glucose levels in the first hours should be applied to all newborn infants. Persistent hypoglycemic syndromes must be identified prior to discharge.