Adrenal function and dysfunction in critically ill patients.

Area of Science:

• Endocrinology
• Critical Care Medicine

Background:

• Critical illnesses increase systemic cortisol, a key stress response. Relative adrenal failure (CIRCI) was thought to impair this response, especially in septic shock.
• Diagnosis of CIRCI was based on suppressed cortisol response to ACTH, regardless of baseline levels, leading to trials using high-dose hydrocortisone with conflicting outcomes.

Purpose of the Study:

• To review novel insights into the hypothalamic-pituitary-adrenal axis response during critical illness.
• To challenge the current definition and diagnostic/treatment guidelines for critical-illness-related corticosteroid insufficiency (CIRCI).
• To propose a new conceptual framework for understanding adrenocortical function in critical illness.

Main Methods:

• Review of recent research on the hypothalamic-pituitary-adrenal axis in critical illness.
• Integration of novel findings into a new conceptual framework.
• Re-evaluation of the concept and management of CIRCI.

Main Results:

• Recent findings challenge the established concept of CIRCI and its diagnostic criteria.
• Existing treatment guidelines for CIRCI may need revision based on new understanding.
• Novel insights necessitate a re-appreciation of adrenocortical function and dysfunction in critically ill patients.

Conclusions:

• The traditional concept of CIRCI and its diagnosis are challenged by new research.
• A revised conceptual framework is proposed to better understand adrenocortical responses in critical illness.
• This framework may guide future research and therapeutic strategies for critical illness-related endocrine dysfunction.