Adrenocorticotropic hormone and cortisol response to corticotropin releasing hormone in the critically ill-a novel assessment of the hypothalamic-pituitary-adrenal axis

Am J Surg. 2012 Feb;203(2):205-10. doi: 10.1016/j.amjsurg.2010.11.015. Epub 2011 Jun 16.

Abstract

Background: The pathophysiology of adrenal insufficiency, common in surgical intensive care units, has not been fully elucidated.

Methods: Patients at risk (age > 55 years, in the surgical intensive care unit >1 week, baseline cortisol < 20 μg/dL) were enrolled. After measuring cortisol and adrenocorticotropic hormone (ACTH), corticotropin-releasing hormone (CRH) was administered. ACTH and cortisol were measured over 120 minutes. Short and long cosyntropin stimulation tests determined adrenal function. Area under the curve (AUC) and mixed linear models were used to compare cortisol and ACTH responses. Patients were grouped according to survival and response to stimulation testing. Chi-square and t tests were performed, and P values < .05 were considered statistically significant.

Results: Six of 25 patients responded poorly to cosyntropin, and 5 died compared with 3 after a normal response (P < .01). ACTH (AUC) and ACTH peak were increased in nonsurvivors after CRH administration. Cortisol peak and AUC were not different.

Conclusions: ACTH responsiveness was increased in nonsurvivors and may predict mortality.

MeSH terms

  • Adrenal Insufficiency / blood*
  • Adrenal Insufficiency / etiology
  • Adrenal Insufficiency / mortality
  • Adrenocorticotropic Hormone / blood*
  • Aged
  • Aged, 80 and over
  • Area Under Curve
  • Corticotropin-Releasing Hormone / administration & dosage
  • Cosyntropin / administration & dosage*
  • Critical Illness
  • Female
  • Humans
  • Hydrocortisone / blood*
  • Hypothalamo-Hypophyseal System / metabolism*
  • Intensive Care Units
  • Linear Models
  • Male
  • Middle Aged
  • Pituitary-Adrenal System / metabolism*
  • Postoperative Complications / blood*
  • Postoperative Complications / mortality
  • Prognosis

Substances

  • Cosyntropin
  • Adrenocorticotropic Hormone
  • Corticotropin-Releasing Hormone
  • Hydrocortisone