Definition
Aspiration pneumonia is a lung infection caused by the entry of foreign objects into the lower airways, such as water, saliva, food, or vomit. Another condition, called aspiration pneumonitis, occurs when foreign objects like food, fluids, saliva, and stomach acid are accidentally inhaled, leading to swelling in the respiratory tract, but without signs of infection. It is challenging to differentiate between aspiration pneumonitis and aspiration pneumonia.
Cases of aspiration pneumonia account for about 5–15% of total community-acquired pneumonia cases. Other reports indicate that about 18% of cases of aspiration pneumonia occur in nursing homes. Aspiration pneumonia is also often experienced by patients being treated in hospitals. Because the occurrence of aspiration or inhalation of foreign bodies is often not visible, the actual number of cases of aspiration pneumonia cannot be determined.
Causes
Talk while eating to prevent food from going into the 'wrong tube' or choking. If you choke, you will cough to expel the foreign object, and the discomfort will disappear once the foreign object is removed from your body. Coughing is a protective mechanism of the respiratory tract against inadvertently ingested foreign objects, thus preventing pneumonitis or pneumonia. Even if the foreign object enters the digestive tract, the healthy individual's immune system can handle the condition, and pneumonia does not occur.
In some people with weakened immune systems or when a large amount of foreign material enters, the immune system cannot deal with the foreign object, leading to lung infection, or pneumonia. Inhaled foreign objects may contain bacteria that later develop in the lungs. The bacteria most commonly causing aspiration pneumonia are those found in the gastrointestinal and oral tracts.
Stomach acid can also cause aspiration pneumonia. If stomach acid rises, the digestive tract can also be burned, causing narrowing of the bronchi in the lower airways, swelling of the mucous membrane (mucosa) of the airways, and bleeding in the air sacs (alveoli) within the lungs. Contamination of the airways due to stomach acid can make the airways more susceptible to bacterial infection, leading to aspiration pneumonia (25% of cases).
Risk factor
Aspiration pneumonia often occurs in people who:
- Are under total anesthesia or undergoing dental procedures
- Are unconscious or experiencing decreased consciousness
- Have seizures
- Have suffered head trauma
- Use feeding tubes
- Experience difficulty coughing or swallowing (dysphagia), which often occurs in patients with brain or nervous system damage, such as stroke, Parkinson's, or multiple sclerosis
- Consume alcohol and abuse drugs in large quantities
- Are over 65 years old. Aspiration pneumonia often occurs in the elderly living in nursing homes
- Have weakened immune systems due to certain medical conditions, or have not yet developed a fully functional immune system (under 5 years old)
- Have gastroesophageal reflux disease (GERD)
- Dementia
Symptoms
Aspiration symptoms appear quickly, possibly around 1–2 hours after choking on a foreign object. Aspiration pneumonia develops 1–2 days after the first choking incident. Visible symptoms of aspiration pneumonia include sudden chest pain or shortness of breath, productive cough with phlegm or coughing up blood, fever, fatigue, and frequent yawning.
Diagnosis
Your doctor will inquire about your complaints, and medical history, and perform a physical examination. One of the challenges in diagnosing aspiration pneumonia is that sometimes you may not be aware of the foreign object inadvertently entering the airway. The doctor will evaluate your lung sounds using a stethoscope. Aspiration pneumonia needs to be suspected in patients who have been hospitalized for a long time or in critical condition. In addition to diagnosing the main complaints and physical examination, your doctor may also perform additional tests as indicated.
Imaging tests can be performed to assess the condition of your lungs. Your doctor may suggest X-ray or CT (Computerized Tomography) scans of the chest area. CT scans are more sensitive to abscesses (pus-filled pockets) in the lungs, which are one of the complications of aspiration pneumonia. Patients who aspirate while upright are more likely to develop pneumonia in both the right and left lobes, while patients who choke in a lying position often develop pneumonia in the right lung lobe.
Another test that can be performed is bronchoscopy, which indicates if the cause of aspiration is food. This examination is performed by inserting a small camera-equipped tube into the lower airways. In addition to imaging tests, blood tests can also be done to assess pH or acidity levels and oxygen levels in the blood.
Management
The main treatment for aspiration pneumonia is antibiotics. The type of antibiotic chosen will depend on several factors, such as allergies and suspected bacterial causes of pneumonia. Pneumonia occurring in hospitals requires antibiotic treatment according to the hospital's guidelines, generally potent antibiotics that can kill a variety of bacteria. The use of antibiotics requires close monitoring by a doctor.
Even though aspiration pneumonitis is not an infection, your doctor may still prescribe antibiotics, but this depends on your current condition and other medical conditions you may have. Additional treatments that may be given include oxygen therapy and mechanical ventilation or a ventilator as a breathing aid, especially in severe cases.
Most people who receive treatment for aspiration pneumonia have a high rate of recovery. The outcome of aspiration pneumonia depends on the overall health condition of the patient and how quickly they receive treatment. Untreated aspiration pneumonia can be dangerous, leading to lung complications and death.
You may experience symptom improvement approximately 1 week after receiving therapy. Although you may return to activities, you may still feel tired. The total healing duration varies from individual to individual, but some people may still feel weak and tired after a month.
Recurrent aspiration pneumonia requires further examination by a doctor. Causes of aspiration pneumonia such as neurological disorders require special management to prevent recurrence. Therapists can help provide exercises to improve the swallowing ability of patients.
Complications
Complications of aspiration pneumonia that may occur include:
- Acute respiratory distress syndrome (ARDS), a severe respiratory disorder that can be life-threatening
- Lung abscess
- Respiratory failure
- Death, about 11–30% of deaths from aspiration pneumonia have been reported
- Repeated hospitalizations
Prevention
Things that can help prevent aspiration pneumonia include:
- Avoiding excessive alcohol consumption and illicit drugs
- Maintaining an upright position while eating
- Chewing food slowly
- Avoiding using nicotine products and smoking habits
- Maintaining oral health
When to see a doctor?
If you experience worrying symptoms such as chest pain, fever, and difficulty breathing, see a doctor immediately. Pneumonia can worsen rapidly and potentially be life-threatening.
If you have difficulty swallowing or choke frequently, consult your doctor immediately. The doctor may need to adjust the medications you are taking. Your doctor may also conduct further examinations to assess your speech and swallowing abilities. The doctor may also suggest changes to your eating and drinking habits.
- dr Hanifa Rahma
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