Catecholamines and free fatty acids in plasma of patients undergoing cardiac operations with hypothermia and bypass.

Plasma concentrations of adrenaline, noradrenaline, and free fatty acids were measured at different stages of cardiac operations in which hypothermia and bypass were used. The rise of adrenaline, noradrenaline, and free fatty acid concentrations in plasma is consistent with the concept that these are important compounds in stress situations such as hypothermia and surgical operations. There is a more marked release of adrenaline and it may be a more specific hormone in response to hypothermia and bypass than is noradrenaline in man.