A significant proportion of critically ill neonates with hypotension in intensive care units do not respond to volume administration or vasopressors/inotropic circulatory support. The incidence of this refractory hypotension or vasopressor-resistant hypotension (VRH), is inversely proportional to gestational age.
VRH can have a major impact on the mortality and morbidity of these patients. Adrenal insufficiency is currently considered to be its main cause.
Particularly relative adrenal insufficiency (RAI) occurs when the amount of cortisol production in the adrenal glands is insufficient for to the severity of illness.This review article summarizes the basics of hypothalamic-pituitary-adrenal axis physiology in the embryonic and fetal period and the fundamental aspects of RAI and VRH pathophysiology in critically ill and very preterm neonates. Diagnostic and therapeutic options, including side effects with regard to the long-therm prognosis of exposed patients, are also discussed.