BackgroundAdrenocortical dysfunction is unusual in the unselected critically ill patient. Case reports document a state of corticosteroid responsive vasopressor dependence, resembling the systemic inflammatory response syndrome. The exact incidence of this disorder is unknown.MethodsWe prospectively studied the incidence of adrenal insufficiency during a 9-month period in a surgical intensive care unit (ICU) population. Trauma, general surgery, urology, and gynecologic-oncology patients were included. Patients who met criteria were given a cosyntropin stimulation test.ResultsOverall, the incidence of adrenal insufficiency was 0.66%. In the subgroup of patients with greater than 14 days stay in the ICU, 6% were found to have adrenal insufficiency. In patients aged more than 55 years and with ICU stays of 14 days or greater, 11% were adrenally insufficient.ConclusionsScreening of critically ill patients for adrenal insufficiency, particularly those with prolonged ICU stay and age greater than 55 years, is warranted.