BACKGROUND

Relative adrenal insufficiency (RAI) is a common complication during septic shock and may be more frequent in specific subgroups. The main objectives of this study were to determine the adrenal function and the RAI incidence in different subgroups of septic shock patients considering: main admission categories (medical, elective or emergency surgery); source of infection; nosocomial or community-acquired infections; gender, age <65 years or >65 years; and the presence or absence of neurological diseases, acute respiratory distress syndrome (ARDS) and bacteremia.

METHODS

Prospective study in a medical-surgical ICU, including adults with septic shock, from May 2002 to May 2005. All patients had total serum cortisol measured at baseline and 60 min after a high-dose ACTH test within the first 96 h of shock onset. RAI was defined as a serum cortisol increment after ACTH test (Deltamax(249)) <90 microg/l.

RESULTS

One hundred and two subjects were enrolled, and the overall RAI incidence was 22.5%. Patients with ARDS before ACTH test or bacteremia showed lower Deltamax(249) values than patients with ARDS after ACTH test (96 vs. 153 microg/l, P=0.02) or without bacteremia (140 vs. 175 microg/l, P=0.04). Multivariate regression analysis revealed that female gender, development of ARDS before ACTH test, and bacteremia were associated with greater RAI incidence. There was no difference in RAI incidence considering neurological diseases, age, type and source of infection and the main admission categories.

CONCLUSIONS

Female gender, bacteremia and early-onset ARDS were variables independently associated with greater RAI incidence in septic shock patients. There was no difference in the RAI incidence concerning other subgroups.