Aspiration pneumonitis (AP) is lung inflammation caused by aspiration of gastric acid or other substances without bacterial infection.

It is also referred to as chemical pneumonitis.

Should be differentiated from aspiration pneumonia, which is caused by bacteria and requires antibiotics.

• • AP has a similar clinical presentation and may be difficult to distinguish.
  • Uncomplicated AP does not require antibiotics.
    • Secondary bacterial infection may occur, requiring antibiotics.
  • Antacids, H2 receptor antagonists, and proton pump inhibitors may increase the likelihood of bacterial aspiration pneumonia.

Patients may present with varying severity based on clinician judgment of:

• • Patient dyspnea (subjective and objective measures).
  • Patient factors (comorbidities, age, cardiorespiratory disease, immunodeficiency, etc.).
  • Vital signs.
  • Wheezes and/or crackles on auscultation.

If an infectious cause is suspected, refer to:

 EMN CS: Community-Acquired Pneumonia (Adult) – Diagnosis

Clinical Presentation

• Possible Signs and Symptoms:
• • Sudden onset dyspnea.
  • Tachypnea.
  • Respiratory distress.
    • Can occur 2-5 hours after aspiration.
  • Non-productive cough.
  • Diffuse wheezes/crackles.
  • Bloody/frothy sputum.

Imaging:

• Chest Xray abnormal.
• CT findings:
• • Centrilobular nodules.
  • Ground-glass opacities.
  • Central airway plugging.
  • Segmental/Lobar atelectasis.
  • Consolidation.
  • No septal lines or reticular interstitial pattern.

Supportive Care as Needed:

• Oxygen for hypoxemia.
• Suctioning.
• Bronchoscopy to clear large obstructions.
• Intubation and mechanical ventilation if severe respiratory compromise.
• Gastric decompression with nasogastric tube to prevent recurrent aspiration.

Antibiotics:

• NOT recommended in:
  • Mild and moderate cases. Monitor and reassess in 48 hours.
    • Does not improve mortality.
    • Increased frequency of antibiotic escalation.
    • Does not reduce the need for escalation of care.
• Consider empiric therapy in:
• • • Severe cases.
    • Small bowel obstruction.
    • Also refer to:
      • EMN CS: Community-Acquired Pneumonia (Adult) – Diagnosis
      • EMN CS: Hospital Acquired Pneumonia (Adult) – Treatment
    • Patients may present with secondary bacterial pneumonia after the initial event.
      • We recommend monitoring for deterioration or unexpected changes prior to use of antibiotics.
      • We acknowledge some clinicians will start antibiotics sooner based on the clinical situation before evidence of patient deterioration.

Glucocorticoids:

• NOT recommended.
  • Increases ICU stay.
  • No significant difference in complications or outcomes.

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   -The New England Journal of Medicine

   
   

2. Aspiration Pneumonia.

   Mandell, L. A., & Niederman, M. S. (2019). , 380(7), 651–663.

   -The New England Journal of Medicine

   
   

3. Acute aspiration pneumonitis.
   Di Muzio, B., & Weerakkody, Y. (2020, September). Retrieved March 9, 2021,

   – Radiopaedia

   
   

4. Aspiration pneumonia and pneumonitis: a spectrum of infectious/noninfectious diseases affecting the lung. Current opinion in infectious diseases.

   Neill, S., & Dean, N. (2019). , 32(2), 152–157.

   – LWW Journals