Ventilator-associated pneumonia (VAP) is the intensive care unit (ICU)–associated infection most frequently acquired among patients receiving mechanical ventilation and is responsible for approximately 50% of all antibiotics prescribed in this setting.1-3 Because VAP has been associated with increased morbidity, longer hospital stays, increased health care costs, and higher mortality rates, prevention of this infection is a major challenge for all ICU personnel.1,2,4,5 Numerous preventive strategies have been tested, and updated recommendations have been published.6-9 However, evaluation of the effect of such interventions is a complex issue.