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Aspiration pneumonia

Last reviewed: 30 Oct 2023
Last updated: 08 Nov 2022



History and exam

Key diagnostic factors

  • cough
  • dyspnea
More key diagnostic factors

Other diagnostic factors

  • fever
  • pleuritic chest pain
  • tachypnea
  • foul-smelling breath
  • crepitations
  • frothy or purulent sputum
  • history of vomiting
Other diagnostic factors

Risk factors

  • chemoradiation for head and neck cancers
  • altered mental status
  • swallowing dysfunction
  • gastrointestinal disease
  • intubation or tracheostomy tube
  • older age
  • poor oral hygiene
  • feeding tube
  • recumbent position
More risk factors

Diagnostic investigations

1st investigations to order

  • O2 saturation
  • CXR
  • CBC
  • sputum Gram stain
  • sputum culture
More 1st investigations to order

Investigations to consider

  • point-of-care lung ultrasound
  • ABG
  • bronchoscopy
More investigations to consider

Treatment algorithm


all patients



Michael J. Lanspa, MD, MS

Adjunct Associate Professor

Division of Pulmonary and Critical Care Medicine

Intermountain Medical Center

University of Utah

Salt Lake City



MJL declares that he has no competing interests.


Dr Michael J. Lanspa would like to gratefully acknowledge Dr Richard Kanner and Dr Krishna Sundar, previous contributors to this topic. DK and KS declares that they have no competing interests.

Peer reviewers

Toby Maher, MB, PhD, MRCP

Consultant Respiratory Physician

Department of Respiratory Medicine

Royal Brompton Hospital




TM has received research funding from the Wellcome Trust and GlaxoSmithKline. He has acted as a paid consultant to GSK, Actelion, and Respironies.

Feras Hawari, MD

Chief of Pulmonary and Critical Care

King Hussein Cancer Center




FH declares that he has no competing interests.

  • Aspiration pneumonia images
  • Differentials

    • Aspiration pneumonitis
    • Atelectasis
    • Pulmonary edema
    More Differentials
  • Guidelines

    • Diagnosis and treatment of adults with community-acquired pneumonia. An official clinical practice guideline of the American Thoracic Society and Infectious Diseases Society of America
    • Practice guidelines for preoperative fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration: application to healthy patients undergoing elective procedures
    More Guidelines
  • Patient leaflets


    More Patient leaflets
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