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Ventilator-Associated Pneumonia



Ventilator-associated pneumonia (VAP) is an infection of the lungs. It affects people who are on mechanical ventilation. Most who need ventilation are very ill and in a care setting. Pneumonia affects the small airways and air sacs in the lungs. It can make it difficult for oxygen to pass into the body.

Alveoli in the Lungs

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VAP is commonly caused by specific bacteria. Mechanical ventilation can increase the risk of pneumonia. The tube that is needed in the throat makes it easier for bacteria to get deep into the lungs.

Risk Factors

Factors that may increase the chances of VAP:

  • Chronic lung disease
  • Conditions that affect the nervous system
  • Weakened immune system
  • Long term antibiotic use
  • Repeated placement of tube in the throat
  • Tube placed through hole in the throat rather than down through the nose or mouth
  • Prolonged ventilation
  • Continuous sedation
  • Prolonged period of lying on back
  • Malnutrition
  • Older age


VAP may cause:

  • Fever
  • Chills
  • Cough
  • Thick mucus, greenish mucus, or pus-like phlegm
  • Bluish color of nails or lips
  • Nausea or vomiting
  • Shortness of breath


The doctor will review symptoms and past health. A physical exam will be done. Tests may include:

  • Blood tests—to measure oxygen, carbon dioxide, and acid in the blood
  • Blood cultures—to look for what may be causing infection
  • Cultures from below the chest tube
  • Chest x-ray—will show fluid or inflammation in lungs
  • CT scan


Treatment depends on which bacteria are causing the pneumonia. Treatment options include:

  • Antibiotics through IV
  • Oxygen therapy—to improve the level of oxygen in the body


To help reduce the chances of VAP, the care team will:

  • Elevate the head of the bed.
  • Wash their hands before and after touching the ventilator.
  • Clean the inside of patient's mouth on a regular basis.
  • Use the ventilator only if it is necessary.
  • Carefully use sedation.
  • Regularly suck fluids out of the airway.

American Lung Association

American Thoracic Society


Public Health Agency of Canada

The Lung Association


Koenig SM, Truwit JD. Ventilator-associated pneumonia: diagnosis, treatment, and prevention. Clin Microbio Rev. 2006;19(4):637-657.

Ventilator-associated pneumonia. Centers for Disease Control and Prevention website. Available at: Updated May 17, 2012. Accessed January 11, 2019.

Ventilator-associated pneumonia. EBSCO DynaMed Plus website. Available at: Updated October 25, 2018. Accessed January 11, 2019.

Last reviewed January 2019 by EBSCO Medical Review Board Monica Zangwill, MD, MPH  Last Updated: 1/8/2019