· Hospital-acquired pneumonia (HAP): ≥48 hrs after hospitalization
· Ventilator-associated pneumonia (VAP): ≥48 hrs after endotracheal intubation
· Ventilated hospital-acquired pneumonia: HAP patients who later require intubation
· Microaspiration of colonized organisms, usually bacterial and from oropharyngeal site
· Direct contact with contaminated equipment or healthcare personnel
· Inhalation of infectious aerosols
· Typical microbiology:
o Aerobic GNR: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter species, Acinetobacter species
o GPC: Staph aureus, Strep species
Risk Factors & Prevention: VAP occurs in ~10% of intubated patients
· Signs/symptoms: Fever, tachypnea, increased purulent secretions, hemoptysis, rhonchi/rales, reduced breath sounds, bronchospasm, worsening hypoxemia, leukocytosis/leukopenia
· Radiographic findings: new/progressive infiltrate
· Altered ventilator mechanics: reduced tidal volume, increased inspiratory pressures
Diagnosis: New infiltrate + infectious signs + positive culture
Treatment: (See flowchart below)
· Empiric therapy depends on risk for resistant organisms.
· Risk for MDR pathogens if ANY of these: Septic shock, IV antibiotics within previous 90 days, ARDS, hospitalization ≥5 days, acute renal replacement therapy, structural lung disease (bronchiectasis, cystic fibrosis)
· Risk for resistant GNR: local antibiogram shows that >10% of GNR are resistant to agent being considered for monotherapy, or prevalence of resistance is unknown
· Risk for MRSA: local antibiogram shows >10-20% of Staph aureus isolates are MRSA, or prevalence of MRSA is unknown
· Narrow based on culture & sensitivity results
o MRSA swab has high negative predictive value. Use this to guide de-escalation.
· Total duration of antibiotic treatment: 7 days
Prognosis: Attributable mortality ~13%
· Adequate antibiotic therapy is important!
· Factors associated with poor outcomes: shock, coma, ARDS, high APACHE score, bacteremia, severe underlying comorbidities, infection caused by MDR organism, multilobar disease, cavitating lesions, rapidly progressive infiltrates, delay in effective antimicrobial therapy
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