Guidelines
Aspiration Pneumonia and Pneumonitis

Aspiration Pneumonia and Pneumonitis

Diagnostic Considerations

Many community and hospital acquired pneumonias are related to aspiration events

The pathogenesis of any pneumonia is largely due to the microaspiration of oropharyngeal flora

5-15% of community acquired pneumonias (CAP) are caused by aspiration pneumonia

Pneumonia vs Pneumonitis

In the case of macroaspiration events:

  • The aspiration of sterile gastric contents often results in a non-infectious chemical aspiration pneumonitis
  • Inhalation of significant quantities of oropharyngeal flora may lead to an infectious aspiration pneumonia

Aspiration pneumonitis:

  • Aspiration of sterile gastric contents or other chemical irritants
  • Initially sterile

Aspiration pneumonia:

  • Aspiration of colonized oropharyngeal flora
  • Aerobic Gram-positives and Gram- negatives more than oral anaerobes

Aspiration pneumonitis: Typically younger, post-stroke, decreased LOC

Aspiration pneumonia: Typically older, frail, with dysphagia and/or gastric dysmotility, polypharmacy

Aspiration pneumonitis: Rapid onset (mins-hours)

Aspiration pneumonia: Delayed (2-7 days after macroaspiration)

No consensus on differentiating radiographic characteristics

More Information

This information is for adults only. Please refer to IWK Firstline app for pediatrics.

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