Causes

Risk factors for aspiration or breathing in of foreign material into the lungs are:

• Being less alert due to medicines, illness, or other reasons
• Coma
• Disorders of the esophagus, the tube that moves food from the mouth to the stomach (esophageal stricture, gastroesophageal reflux)
• Drinking large amounts of alcohol
• Medicine to put you into a deep sleep for surgery (general anesthesia)
• Old age
• Poor gag reflex in people who are not alert (unconscious or semi-conscious) after a stroke or brain injury
• Problems with swallowing

Acidic material that is breathed into the lungs can cause severe lung injury. However, it may not necessarily lead to pneumonia.

Symptoms

• Bluish discoloration of the skin caused by lack of oxygen
• Chest pain
• Cough
  • With foul-smelling phlegm (sputum)
  • With sputum containing pus or blood
  • With greenish sputum
• Fatigue
• Fever
• Shortness of breath
• Wheezing

Other symptoms that can occur with this disease:

• Breath odor
• Excessive sweating
• Swallowing difficulty

Exams and Tests

A physical examination may reveal:

• Crackling sounds in the lungs
• Decreased oxygen
• Rapid pulse (heart rate)

The following tests may also help diagnose this condition:

• Arterial blood gas
• Blood culture
• Bronchoscopy
• Chest x-ray
• Complete blood count (CBC)
• CT scan of the chest
• Sputum culture
• Swallowing studies

Treatment

Some people may need to be hospitalized. Treatment depends on the severity of the pneumonia. You may receive antibiotics, which treat bacteria. Some people may get special antibiotics to treat bacteria that live in the mouth.

The type of bacteria that caused the pneumonia depends on:

• Your health
• Where you live (at home or in a long-term nursing facility, for example)
• Whether you've recently been hospitalized
• Recent antibiotic use

You may need to have your swallowing function tested. Patients who have trouble swallowing may need to use other feeding methods to reduce the risk of aspiration.

Outlook (Prognosis)

The outcome depends on:

• The severity of the pneumonia
• The type of bacteria causing the pneumonia
• How much of the lungs are involved

If acute respiratory failure develops, the patient may have a long-term illness or die.

Many people who have aspiration pneumonia have other serious health problems, which may affect the outlook for recovery.

Possible Complications

• Acute respiratory distress syndrome
• Low blood pressure
• Pneumonia with lung abscess
• Shock
• Spread of infection to the bloodstream (bacteremia)
• Spread of infection to other areas of the body

When to Contact a Medical Professional

Call your health care provider, go to the emergency room, or call the local emergency number (such as 911) if you have:

• Chest pain
• Chills
• Fever
• Shortness of breath
• Wheezing

Prevention

• Avoid behaviors that may lead to aspiration, such as excessive alcohol use
• Become aware of the risk of aspiration

Alternative Names

Anaerobic pneumonia; Aspiration of vomitus; Necrotizing pneumonia; Aspiration pneumonitis

References

Donowitz GR. Acute pneumonia. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 64.

Torres A, Menéndez R, Wunderink R. Pyogenic bacterial pneumonia and lung abscess. In: Mason RJ, Broaddus VC, Martin TR, et a. Murray & Nadel's Textbook of Respiratory Medicine. 5th ed. Philadelphia, Pa: Saunders Elsevier; 2010:chap 32.

Update Date: 2/19/2012

Reviewed by: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine; and Denis Hadjiliadis, MD, Assistant Professor of Medicine, Division of Pulmonary, Allergy and Critical Care, Unviersity of Pennsylvania, Philadelphia, PA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.