In vivo measurements of glucose absorption in preterm infants

Few data are available regarding the kinetics of glucose absorption in the preterm infant. In order to ascertain the kinetics of glucose absorption in the premature infant and how rate of infusion and concentration affect abs orption, jejunal glucose absorption kinetics were measured in 16 preterm in fants by infusing 1, 10, and 100 mM glucose solutions in random order, Seve nteen infants were perfused with glucose (100 mu mol/min) by infusing 67 mM glucose at 1.5 ml/min and 133 mM glucose at 0.75 ml/min to determine the e ffect of changes in rate of infusion vs, concentration on glucose absorptio n, K-m and V-max were related to postnatal age. K-m was correlated inversel y with the percentage of feedings received as human milk. Antenatal adminis tration of glucocorticoids appeared to increase V-max. The higher infusion rate resulted in greater glucose absorption than the higher concentration g lucose solution. Conclusions: The characteristics of glucose absorption in the preterm infant change with age and are affected by diet, glucocorticoid s, and the method of infusion. These data have implications for the feeding of preterm infants.