Secondary infections remain a major cause of mortality in critically ill patients, mainly because of high prevalence of multidrug-resistant microorganisms. Therefore strategies aimed to reduce the incidence of ventilator-associated pneumoniae (VAP) and bloodstream infections are of utmost important. There is robust data on selective digestive decontamination (SDD) efficacy in reduction of secondary infections in intensive care units (ICU) with low rates of antibacterial resistance. However the data received from hospitals with moderate-to-high rates of resistance is equivocal. This as an interventional parallel open-label study investigating the effect of selective digestive decontamination on the rates of ventilator-associated pneumonia in critically ill patients admitted to the ICU with high prevalence of drug-resistant bacteria. Secondary outcomes include rates of bloodstream infections, mortality, duration of mechanical ventilation, duration of ICU stay, resistance selection and overall antibiotic consumption.