PK/PD Target Attainment of Ceftriaxone for the Prevention of Early Ventilator-associated Pneumonia in Neurologically Injured Patients

Inclusion Criteria: * 18 years or older * Admitted in intensive care unit for acute brain injury, including traumatic brain injury and cerebral vascular disease * Glasgow coma scale inferior to 12 * Orotracheal intubation in first 12 hours of admission * Needed of invasive mechanical ventilation for at least 48 hours Exclusion Criteria: * Acute brain injury related to tumoral or infectious process * Antibiotic therapy administered before acute brain injury for an other pathology * Patients with a risk of multiresistance bacteria contamination (stay in a risk area in the past 3 months, antibiotic therapy with fluoroquinolone or betalctamine in the past 3 months, hospitalization in last month before admission, documented contaminationwith multiresistance bacteria, immunodepression) * Patients with hish risk of death in the first 48 hours * Patients with a beta-lactams reported allergy