Placental transfer of glucose-amino acid complexes present in parenteral solutions

Intravenous infusion of glucose-amino acid complexes, formed during heat sterilization of mixtures of glucose and amino acids or protein hydrolysates, has been associated with mild dehydration in infants, and with excessive trace metal ion excretion in both infants and adults. When parenteral solutions containing these glucose-amino acid complexes were infused into pregnant rhesus monkeys, the compounds accumlated in the maternal plasma and were transported to the fetal circulation. Although all of the compounds studied crossed the placenta, fetal levels were consistently lower than maternal levels. Amniotic fluid concentrations of these compounds increased progressively with the length of maternal infusion, presumably through fetal urination into the amniotic sac. In animals infused with solutions not heat sterilized, levels of these compounds could not be detected in maternal plasma and urine, fetal plasma and urine, or in amniotic fluid. In view of possible toxicity of the glucose-amino acid complexes, parenteral solutions containing these compounds should probably be avoided in the intravenous nutrition of the pregnant woman.