Ventilator-associated pneumonia
Ventilator-associated pneumonia is a new pulmonary infiltrate with clinical signs of infection developing more than 48 hours after endotracheal intubation, driven by gram-negative bacilli and Staphylococcus aureus; empiric antipseudomonal therapy is started immediately from a semiquantitative respiratory culture and paired with ventilator-bundle prevention.
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What this article covers
- Overview
A nosocomial pneumonia defined purely by intubation and timing: ventilator-associated pneumonia (VAP) is pneumonia developing more than 48 hours after endotracheal intubation, occurring in about 10%…
- Epidemiology
Occurs in about 10% of ventilated patients, with risk accumulating for each day of intubation.
- Risk factors
Duration of endotracheal intubation: cumulative daily risk while intubated is the dominant driver.
- Pathophysiology
Microaspiration around the endotracheal tube cuff: secretions pooled above an imperfectly sealed cuff leak into the lower airway, seeding organisms that colonize the oropharynx and stomach with hospital flora within days of intubation.
- Clinical features
New or progressive infiltrate on chest imaging plus at least one sign of infection: fever above 38 degrees C (100.4 degrees F), leukocytosis or leukopenia, purulent tracheal secretions, or a decline…
- Differential diagnosis
Hospital-acquired pneumonia: the same syndrome and organisms but occurring in a nonintubated patient more than 48 hours after admission; distinguished purely by intubation status.
- Diagnosis
VAP is diagnosed by a new or progressive infiltrate plus clinical signs of infection, with no formal severity-grading criteria beyond hemodynamic and oxygenation status: established when a new or…
- Management
First, obtain endotracheal aspirate and blood cultures, then start empiric antibiotics without waiting for results, because delay raises morbidity and mortality.
- Complications
Septic shock, requiring vasopressor support and fluid resuscitation per the sepsis pathway.
- Prognosis
About half of patients with hospital-acquired and ventilator-associated pneumonia develop a serious complication (respiratory failure, pleural effusion, septic shock, empyema, or kidney injury), making VAP a high-morbidity diagnosis.
- Prevention
Elevate the head of the bed to 30 to 45 degrees rather than supine, particularly for patients receiving enteral nutrition, who carry the highest aspiration risk when supine.
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