Treatment of Ventilator-Associated Pneumonia Empirically chosen antibiotics active against resistant organisms If ventilator-associated pneumonia is suspected, treatment is with antibiotics that are chosen empirically based on Local sensitivity patterns Patient risk factors for antibiotic-resistant pathogens In the 2007 guidelines, the Infectious Diseases Society of America and the American Thoracic Society used very broad criteria for defining the population at risk of infection with antibiotic-resistant pathogens, which resulted in the majority of patients with VAP requiring broad-spectrum antibiotic therapy for MRSA and resistant Pseudomonas.