1 Departments of Pediatrics, University of Illinois College of Medicine and Michael Reese Hospital and Medical Center, Chicago
The rate of disappearance of an exogenous load of glucose (1 gm/kg) administered rapidly intravenously is reduced in premature infants under 3 days of age as compared to infants over 7 days of age, children, and adults. Premature infants are not leucine sensitive and respond to tolbutamide with less of a hypoglycemia under 3 days of age than after 7 days. Galactose (1 gm/kg) is cleared more slowly in the premature infant than the adult, but is rapidly converted to glucose. After intravenous fructose (1 gm/kg), there is a transient drop in blood glucose and an immediate rise in lactic acid in the premature infant. Subsequently, a hyperglucosemia occurs. Glucagon and glucagon plus epinephrine produce a hyperglycemic response in the premature infant; the hyperglycemia being greater after 7 days of age as compared to that between 3 to 7 days. In the premature infant, the metabolic needs of the relatively large brain, which is glucose dependent and is not insulin sensitive, may exceed the capacity of the liver to produce glucose during fasting. This may explain the relatively low levels of glucose in the blood of these infants.
Submitted on May 14, 1963