Table 1.

The causative pathogens and risk factors for VAP.

Type of pathogens		Risk factors
		Host-related	Intervention-related
Bacterium	Methicillin-sensitive Staphylococcus aureus MRSA Pseudomonas aeruginosa Acinetobacter baumannii Streptococcus pneumoniae Escherichia coli Klebsiella pneumoniae Anaerobic bacteria Legionella ESBL-PE	Medical history and underlying illness Male Age > 60 years Prior central nervous system disorder Immunocompromised Acute underlying diseases Emergent surgery Surgical history Organ failure ARDS COPD Burns ECOM Ulcer disease	Peri-operative transfusion of blood products Duration of the mechanical ventilation Reintubation Supine head position in patients receiving enteral nutrition Enteral nutrition Absence of subglottic secretion drainage Intra-hospital transports Continuous sedation, use of paralytic agents Nasogastric tubes Tracheostomy Frequent ventilator circuit changes Intracuff pressure of less than 20 cm H2O Prior intravenous antibiotic use within 90 days
Fungus	Aspergillus Candida
Virus	Influenza Respiratory syncytial virus

VAP, ventilator-associated pneumonia; MRSA, methicillin-resistant Staphylococcal aureus; ESBL-PE, extended-spectrum β-lactamase–producing Enterobacteriaceae; ARDS, acute respiratory distress syndrome; COPD, chronic obstructive pulmonary disease; ECMO, extra-corporeal membrane oxygenation.