As part of a study of the role of catecholamines during the newborn's adaptation to extra-uterine life, the excretion of dopamine, norepinephrine, and epinephrine in the urine of nine full-term and 11 premature infants was determined on the first and fifteenth day after birth. The following observations were made.
On the first day the excretion of dopamine by the premature infants was questionably less than that by full-term infants. On the fifteenth day, excretion by the premature infants had more than tripled in amount, whereas that by the full-term infants had increased only by about 50%.
On the first day, the norepinephrine excreted by premature infants was about one third of the amount excreted by full-term infants. On the fifteenth day, although the amount excreted had increased, it remained lower than the amount excreted on the first day by the full-term infants.
On the first day, the amount of epinephrine excretion by premature and full-term infants differed very slightly. On the fifteenth day, excretion by both groups had increased so that the amounts were about equal. The difference noted between premature and full-term infants in this study and the high amount of VMA excreted by premature infants on the fifteenth day measured in a previous study, permit the supposition of a defect in catecholamine biosynthesis—a defect due to an insufficiency of the enzymatic system of dopamine-oxidase and of catechol-O-methyl-transferase.
Role of EEG background activity, seizure burden and MRI in predicting neurodevelopmental outcome in full-term infants with hypoxic-ischaemic encephalopathy in the era of therapeutic hypothermia
