Adrenocortical function in patients with ruptured aneurysm of the abdominal aorta

Objective: To investigate adrenocortical function in patients with ruptured aneurysm of the abdominal aorta. Design: Prospective clinical investigation. Setting: Surgical intensive care unit in a university teaching hospital and intensive care unit in a general hospital. Patients and participants: 54 patients with a documented rupture of the abdominal aorta. Interventions: A short adrenocorticotrophic hormone (ACTH) stimulation test was performed. Measurements and results: Patients were studied within 24 h of admission to the hospital. Blood samples for the measurement of cortisol and ACTH were collected at 0800 h. Subsequently 0.25 mg tetracosactrin (Synacthen) was injected i.v. and after 60 min cortisol measurement was repeated. The criterion for a normal short ACTH test was: stimulated or unstimulated cortisol levels greater than or equal to 0.55 mu mol/l. For the group as a whole, an unstimulated plasma cortisol level of 0.76 mu mol/l was comparable to that in other groups of critically ill patients with similar severity of illness. Between survivors and non survivors, significant differences were found between unstimulated plasma cortisol levels (0.70 vs 1.03 mu mol/l), stimulated plasma cortisol levels (1.00 vs 1.30 mu mol/l), and plasma ACTH levels (72 vs 133 ng/l). One patient did not meet the criteria for normal adrenocortical function: unstimulated plasma cortisol 0.26 mu mol/l, stimulated plasma cortisol 0.47 mu mol/l. Conclusions: In the patients studied with ruptured aneurysm of the abdominal aorta, adrenocortical response was comparable to that in other groups of critically ill patients with similar severity of illness. High cortisol levels were associated with mortality. One patient did not meet the criteria for normal adrenocortical function but survived without steroid treatment.