Relationship between Glucose Utilization Rate and Glucose Concentration in Preterm Infants

Abstract

Within the neonatal euglycemic range, we studied the relationships among total glucose entry, intravenous glucose infusion, endogenous glucose production, glucose disposal rate and blood glucose concentration in infants ≤ 32 weeks gestation. [U-¹³C]-glucose was used as a tracer of glucose metabolism, administered as a primed constant infusion. Using a glucose clamp technique, at least one steady-state period of blood glucose concentration in 10 infants and two steady-state periods of blood glucose concentration in 6 infants were achieved. In the 6 infants studied at 2 glucose concentrations, glucose disposal rate increased with blood glucose concentration, r = 0.95, p < 0.01, slope = 0.091 ± 0.058 (SD) mg·min^––1·kg^––1 per mg·dl^––1 of glucose concentration increase. In all infants studied, intravenous glucose infusion rate was not different from glucose disposal rate, suggesting the absence of endogenous glucose production.