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Clinical presentation and diagnostic evaluation of ventilator-associated pneumonia

Marin H Kollef, MD
Section Editors
Scott Manaker, MD, PhD
John G Bartlett, MD
Deputy Editor
Geraldine Finlay, MD


Ventilator-associated pneumonia (VAP) is a type of hospital-acquired pneumonia that develops after more than 48 hours of mechanical ventilation. Patients with severe hospital-acquired pneumonia who require mechanical ventilation after the onset of infection do not meet the definition of VAP. VAP is a common and serious problem in the intensive care unit that is associated with an increased risk of death. Accurate diagnosis is important so that appropriate treatment can be instituted early while simultaneously avoiding antibiotic overuse and consequently, antibiotic resistance.

The clinical presentation and diagnosis of VAP are reviewed here. The epidemiology, pathogenesis, and risk factors for VAP as well as its prevention and treatment are discussed separately. (See "Treatment of hospital-acquired and ventilator-associated pneumonia in adults" and "Risk factors and prevention of hospital-acquired and ventilator-associated pneumonia in adults" and "The ventilator circuit and ventilator-associated pneumonia".).


Clinical features — Most patients with VAP present with a gradual or sudden onset of the following [1]:

Symptoms – dyspnea (few patients have symptoms since most are nonverbal on mechanical ventilation)

Signs – fever, tachypnea, increased or purulent secretions, hemoptysis, rhonchi, crackles, reduced breath sounds, bronchospasm

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Literature review current through: Nov 2017. | This topic last updated: Nov 06, 2017.
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