Plasma Adrenaline and Noradrenaline in the Neonatal Period, and Infants With Respiratory Distress Syndrome and Placental Insufficiency

The fluorometric method of Weil-Malherbe and Bone was used to investigate plasma catecholamine levels in the neonatal period. Full-term normal infants were found to have plasma adrenaline levels of 0.35 ± 0.64 µg/l and noradrenaline levels of 2.39 ± 2.69 µg/l. Premature infants had plasma adrenaline levels of 0.86 ± 1.21 µg/l and noradrenaline levels of 3.24 ± 2.03 µg/l. Twelve premature infants with the respiratory distress syndrome showed a significant and fourfold increase in adrenaline concentration and a nonsignificant increase in the level of noradrenaline. In seven infants with placental insufficiency and postmaturity there was a significant and eightfold increase in adrenaline. The importance of these findings is discussed, particularly with respect to hypoxia.