RESPONSE OF THE ADRENAL CORTEX DURING EXCHANGE TRANSFUSION AND MAINTENANCE OF THE LOW CORTISOL/CORTISONE RATIO IN THE NEONATAL PERIOD

Abstract

By means of a specific isotope technique the individual corticosteroids were determined in the blood samples successively collected during an exchange transfusion. In 5 infants the adrenal cortex responds by a marked increase in the plasma cortisol concentration. The cortisone concentration is almost constant during the exchange transfusion, but is essentially higher than in normal adults. Earlier investigations have shown that the cortisol/cortisone ratio in the mother at the time of delivery is about 11, while it is 0. 7 in the infant. During the exchange transfusion an increase is seen in the ratio caused by the increase in cortisol concentration. Some hours after termination of the exchange transfusion the cortisol/cortisone ratio again falls to a value near that observed before the exchange transfusion.