Aspiration Pneumonia: Causes, Symptoms & Treatment

Aspiration pneumonia is a lung infection that occurs after fluids from your mouth, throat, esophagus, or stomach get inhaled into your lungs. It is more serious than pneumonia caused by a cold or flu.

what is aspiration pneumonia

Risk factors for aspiration pneumonia include recent intubation, anesthesia, or lung surgery. This is more serious than pneumonia from a cold or flu.

© Andrey Shevchuk | Getty Images

When you inhale fluid or food into your lungs, it is called aspiration. The fluid may be secretions from your mouth, throat, or esophagus. It may be food or liquids from your diet. It may also be gastric juices or vomit from your stomach. When you aspirate, it causes an immediate reaction of lung swelling called pneumonitis. If the aspiration causes a lung infection, it is called aspiration pneumonia.

Causes | Treatment | Recovery

Aspiration pneumonia is usually more serious than the usual type of pneumonia you may get from bacteria or viruses in the air or after a cold or flu infection. Aspiration pneumonia is a life-threatening infection that needs to be quickly diagnosed and treated in the hospital.

Causes of Aspiration Pneumonia

The most common cause is bacteria from the mouth, throat, or esophagus. Gastric fluids usually do not have bacteria and are more likely to cause pneumonitis. The types of bacteria that cause aspiration pneumonia are different than the bacteria and viruses that cause more common pneumonia that starts outside the hospital, called community-acquired pneumonia.

Aspiration pneumonia is rare in people who are healthy and alert because the normal reaction of the throat is to close off the voice box and cough up any aspirated fluids or food particles, called a cough reflex. Healthy lungs can also remove bacteria by moving bacteria out of the lungs and by attacking bacteria with white blood cells called macrophages.

If bacteria from aspiration can not be removed and infection starts, pus, and fluid fill up the tiny air sacs of the lungs, called alveoli. This makes it hard to breathe and get enough oxygen into your blood. People who do not have the ability to close off their voice box, cough, or fight infection are at the highest risk for aspiration pneumonia. Some common risk factors include:

  • Drug or alcohol intoxication
  • Stroke
  • Seizure
  • General anesthesia
  • A breathing tube (endotracheal tube or tracheotomy)
  • Dementia
  • Throat or lung surgery
  • A tube from the nose to the stomach (nasogastric tube)
  • A blocked esophagus or stomach
  • Severe vomiting

Diagnosis and Treatment of Aspiration Pneumonia

Aspiration pneumonia is usually diagnosed by sudden symptoms of shortness of breath, fever, and decreased oxygen levels in a person who is at risk. People who are able to cough may cough up discolored sputum. People who are alert may complain of difficulty breathing and chest pain. A doctor examining the person with aspiration pneumonia may hear crackling noises in the lungs or decreased airflow. A person with very low oxygen may have blue-colored lips or fingernails, called cyanosis.

Diagnosis of aspiration pneumonia may be confirmed when a chest x-ray or CT scan imaging study of the lungs shows areas of lung infection called infiltrates. Once the diagnosis of aspiration pneumonia is made, a combination of intravenous antibiotics are started that will kill the most common bacterial causes of aspiration pneumonia. A tube may be passed into the lungs to clear fluids and pus and to sample the bacteria inside the lungs. In some cases, the antibiotics may be changed according to the sample results.

Other treatments may include giving oxygen and medications that decrease swelling, called steroids. In severe cases, a tube may be placed through the voice box (endotracheal tube), and breathing may be supported by a mechanical ventilator. The goals of treatment are to treat the infection, support breathing, and prevent any more aspiration.

Home Treatment After Aspiration Pneumonia

People who may be at continued risk for aspiration pneumonia may need to work with a therapist to learn ways to eat and drink that reduce the risk of aspiration. A dietician may make changes in the diet to make swallowing easier. The head of the bed may be elevated to prevent gastric fluids from flowing up into the throat while sleeping or resting.


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Chris Iliades, MD

Dr. Chris Iliades is board-certified in Ear, Nose and Throat and Head and Neck Surgery from the American Board of Otolaryngology and Head and Neck Surgery. He holds a medical … Read More

View all posts by Chris Iliades, MD

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