Exclusion criteria included pregnancy, age < 18 years, moribund patients, immunosuppression, and long-term or short-term corticosteroid treatment within the past 4 weeks. A cosyntropin stimulation test with 250 ��g cosyntropin was performed in all septic shock patients. A 50 mg intravenous bolus of hydrocortisone was then administered every 6 hours, beginning within the first 12 hours of septic shock, for at least 5 days, tapered and stopped in 5 days according to the reversal of shock. Patients were grouped as those having received etomidate for intubation (etomidate cohort) versus those subjects having received another hypnotic (non-etomidate cohort).DefinitionsSeptic shock was defined by evidence of infection and a systemic response to infection, in addition to systolic blood pressure < 90 mmHg, despite adequate fluid replacement, or a need for vasopressors for at least 1 hour, according to the American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference Committee criteria [32]. Nonresponse to the cosyntropin stimulation test using an immunoradiology assay (SP2100; Beckmancoulter SAS, Roissy, France) was defined by a delta cortisol (60 minutes after 250 ��g cosyntropin) < 9 ��g/dl [15,26,28]. CIRCI was defined by a delta cortisol (60 minutes after 250 ��g cosyntropin) < 9 ��g/dl or a baseline plasma cortisol level < 10 ��g/l [12].Data collectionA standardized data collection instrument and guidance tool was developed for data collection. Record review and data extraction were performed by a single investigator (NC) and regular meetings were conducted to address any problems encountered during the data collection phase according to the recommendations that have been published to minimize validity threats in chart review studies [33]. Upon ICU admission, the baseline characteristics and the main variables obtained before intubation were recorded either by a nurse (from June 2006 to Jan 2009) or by computer-driven software plugged to the monitor, which recorded automatically all the variables.At the time of intubation, clinical data including reason for intubation, interventions including sedative agent used, need for and doses of vasopressors were recorded. During the intubation procedure, drug administration and the difficulty to intubate rate (defined by three or more attempts at laryngoscopy to place the endotracheal tube into the trachea and/or > 10 minutes using conventional laryngoscopy and/or the need for another operator) [5] were documented.