Design: Prospective, randomized, controlled trial, with 2 groups: study (automated control of cuff pressure) and control (standard control of cuff pressure). Setting: Respiratory Intensive Care Unit (RICU). Subjects: Patients >18 yr, intubated and ventilated. Interventions and measurements: Study group (cuff pressure will be kept constant at 25 cmH2O with the automatic device) and control group (cuff pressure control every 8 h. at the same level using a manual pressure controller, according with standard routine); recording of clinical variables at admission and during RICU stay, and end-point variables (incidence of VAP, etiologic microorganisms, RICU and hospital stay, RICU and 60-d mortality. Expected results: Lower incidence of VAP in study group, compared with control group.