This study seeks to assess whether coma patients really benefit from the use of antibiotics as a prophylactic for reducing the incidence of early ventilator-associated pneumonia in this population group. For this we consider the use of ampicillin sulbactam antibiotic which has a low ability to induce resistance, efficacy and safety observed during the time that has been used, even in patients with neurosurgical pathology, and to be broadly available in our environment.