Glucose kinetics in glucose-infused small for gestational age infants.

To evaluate the maturation of glucose homeostasis in the small for gestational age (SGA) neonate, glucose kinetics were measured with 78% enriched D-[U-13C]glucose by the prime plus constant infusion technique in nine SGA infants and compared with the rate obtained in seven term appropriate for gestational age infants and 13 preterm appropriate for gestational age infants. All of the infants had received glucose intravenously from birth and continued to receive the glucose infusion throughout the study. Fasting plasma glucose and plasma insulin concentrations and plasma [13/12C]ratios were measured during the steady state turnover period. From this data, the glucose production rate was derived. During the turnover period, the SGA and both groups of appropriate for gestational age infants had similar average plasma glucose, plasma insulin, plasma glucagon concentrations, and similar persistent rates of glucose production during glucose infusion. We conclude that under stimulation of glucose infusion, the SGA infant and his AGA counterpart have similar hormonal regulatory responses as well as functional integrity in handling glucose during the second day after birth.