Aspiration Pneumonitis / Pneumonia

Aspiration Pneumonitis / Pneumonia

  • Dysphagia
  • Degenerative neurologic diseases (e.g. dementia, post-stroke, Parkinson’s Disease, multiple sclerosis)
  • Anatomical abnormality or mechanical interference of upper gastrointestinal tract (e.g. enteral feeding, nasogastric tube, endotracheal intubation)
  • Esophageal disorders (e.g. strictures, vomiting + small bowel obstruction, achalasia)
  • Altered level of consciousness (e.g. acute alcohol or substance abuse, seizures, CNS depressants, etc.)
  • Cardiac arrest

Aspiration/Chemical Pneumonitis

  • Inflammatory response to chemical injury caused by inhalation of sterile gastric contents.
  • Episode of macroaspiration is often witnessed and typically occurs in patients with decreased level of consciousness.
  • Characterized by a sudden onset of prominent dyspnea, tachycardia, hypoxemia, low-grade fever, and crackles or diffuse wheeze
  • Symptoms may range from mild to severe and can develop within 2 to 5 hours
  • Pulmonary infiltrates are apparent on x-ray

Aspiration Pneumonia

  • Usually a clinical diagnosis in a patient with predisposing risk factors to aspiration, compatible radiographic evidence occurring in dependant lung segment and characteristic clinical history indicative of infection (e.g. fever, cough, etc.).
  • Episode of aspiration often not witnessed.
  • Right lower lobe most commonly implicated in ambulatory patients. Posterior upper and superior lower lobes most commonly implicated in bed bound patients.

Additional Information

Guideline content derived from:

  • NB Provincial Health Authorities Anti-Infective Stewardship Committee. Antimicrobial Therapy for Adult Aspiration Pneumonia. 10-2020.
  1. DiBardino DM, Wunderink RG. Aspiration pneumonia: A review of modern trends. J Crit Care. 2015 Feb;30(1):40-8.
  2. Marik PE. Aspiration pneumonitis and aspiration pneumonia. N Engl J Med. 2001 Mar 1;344(9):665-71.
  3. Japanese Respiratory Society. Aspiration Pneumonia. Respirology. 2009 Nov;14 Suppl 2:S59-64.
  4. Komiya K, Ishii H, Kadota J. Healthcare-associated Pneumonia and Aspiration Pneumonia. Aging Dis. 2014 Feb 8;6(1):27-37.
  5. Blondel-Hill E, Fryters S. Bugs & Drugs App. Edmonton: Capital Health (Accessed August 8, 2019)
  6. Bartlett JG. Aspiration Pneumonia in Adults. In: UpToDate, Sexton DJ (Ed), UpToDate, Waltham, MA. (Accessed on August 8, 2019.)
  7. Vlad Dragan, Yanliang Wei, Marion Elligsen, Alex Kiss, Sandra A N Walker, Jerome A Leis, Prophylactic Antimicrobial Therapy for Acute Aspiration Pneumonitis, Clinical Infectious Diseases, Volume 67, Issue 4, 15 August 2018, Pages 513–518,
  8. Spectrum Mobile Health App. Eastern Health St. Johns; Island Health Vancouver; AHS Calgary Zone; Fraser Health BC; Providence Health Care Vancouver; Saskatchewan Health Authority. (Accessed August 8, 2019)
  9. Mandell LA, Niederman MS. Aspiration Pneumonia. New England Journal of Medicine. 2019;380(7):651-663.