Go back


    Aspiration Pneumonitis – Diagnosis & Treatment

    Critical Care / Resuscitation, Respiratory

    Last Updated May 03, 2021
    Read Disclaimer
    By Tong Lam, Dave Zhu


    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.

    Diagnostic Process

    If an infectious cause is suspected, refer to:



    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.


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

    Recommended Treatment

    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.


    • 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:


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

    Quality Of Evidence?


    Glucocorticoids not recommended. Multiple studies showing no benefit.


    Antibiotics not recommended in mild and moderate cases. Multiple studies showing no difference in outcomes.


    Related Information

    Reference List

    Relevant Resources


    View all Resources



    Thoracic Ultrasound: Pneumonia

    View all Videos


    COMMENTS (0)

    Add public comment…