['To determine the impact of physiologic doses of hydrocortisone on neurologic outcome after traumatic brain injury (TBI).', 'We conducted a retrospective study in a neurocritical care unit at a university teaching hospital. We included 29 patients with moderate and severe TBI requiring vasoactive drugs to maintain adequate arterial blood pressure who received corticosteroid. Infected patients were excluded. Blood cortisol levels were measured before and 30 and 60 minutes after the administration of a high-dose corticotropin stimulation test (HDST). Patients received hydrocortisone replacement therapy (200-300 mg/day) and vasoactive drugs requirements were noted. Intracranial pressure was managed according to a predefined protocol.', 'A total of 14 out of 29 (48%) of patients were classified as responders to hydrocortisone (stopping vasoactive drugs within 3 days of starting hydrocortisone). The Glasgow Outcome Score (GOS) was used to assess neurologic outcome at 6 months. A favorable outcome (GOS 4 and 5) was observed in 11 out of 14 (79%) of responders and five out of 15 (33%) of nonresponders (p = 0.03). Of the responders, 12 out of 14 (85%) had a baseline cortisol below 414 nmol/L, and five out of 14 (36%) had primary adrenal insufficiency (AI) (primary AI: low baseline cortisol, and poor response to the HDST). Age, severity of injury, and response to hydrocortisone were predictive of outcome in multiple logistic regression analysis.'] Is hemodynamic steroid responsiveness predictive of neurological outcome after traumatic brain injury?