Effect of hypothermia on plasma metabolites in preterm newborn infants with particular references to plasma free amino acids.

Blood glucose, blood lactate, plasma free fatty acids, plasma alpha-amino nitrogen, plasma free amino acids and blood urea nitrogen were measured in 15 hypothermic preterm infants (mean rectal temperature: 34.5 +/- 0.28 degrees C) during a 2-hour 'warming-up' period following admission to our neonatal intensive care unit. Hypothermia was associated with lactacidemia and hyperalaninemia. The increase in body temperature of the infants resulted in the decrease of lactacidemia and hyperalaninemia. Normal levels of other metabolites remained unchanged.