Overview of Aspiration Pneumonia in Dogs
Aspiration pneumonia is an inflammatory lung disorder that occurs when your dog inhales a foreign substance. This most commonly occurs with disorders that cause regurgitation or vomiting. But, neuromuscular disorders that cause difficulty swallowing or paralysis of the esophagus can also lead to aspiration pneumonia. Dogs are more often affected than cats, and depending on the underlying cause, different ages and breeds are affected.
Causes of Aspiration Pneumonia in Dogs
Oropharyngeal (mouth and throat) disorders
Diseases of the larynx or laryngeal surgery
Brachycephalic syndrome – upper airway obstruction that occurs in short nosed breeds of dogs
Esophageal disorders, such as esophageal obstruction from foreign bodies or masses, inflammation of the esophagus, or paralysis and enlargement of the esophagus (megaesophagus)
Polyneuropathy – a dysfunction of many different nerves
Polymyopathy – an inflammatory or immune disorder of the muscles
Decreased mentation or alertness causing a decrease in the swallowing reflex, caused by general anesthesia, sedation, head trauma, or a seizure
Accidental administration of medications, fluids, or foodstuffs into the wind pipe rather than the esophagus, especially during force feeding or tube feeding
Vomiting, especially chronic vomiting
What to Watch For
Signs of aspiration pneumonia in dogs may include:
Respiratory distress, with rapid breathing and a high heart rate
Cyanosis (blue color to the mucus membranes)
Exercise intolerance, weakness
Loss of appetite
Diagnosis of Aspiration Pneumonia in Dogs
A thorough physical examination with auscultation of the chest (listening to the chest through a stethoscope) and palpation of the abdomen are very helpful in detecting changes that could indicate the presence of aspiration pneumonia. Additional tests may include:
Your veterinarian may choose to run some laboratory tests such as a complete blood count (CBC), biochemical profile, and urinalysis to search for evidence of infection and the presence of an underlying cause.
Chest X-rays can show changes in the lung that may indicate aspiration pneumonia.
Fluid may be retrieved from the lower airway and lungs for examination under the microscope, and it may be cultured to isolate causative bacteria and identify a proper antibiotic to use in treatment.
If the animal is in respiratory distress, a blood gas analysis may be considered.
Various other tests may be needed to identify an underlying cause of vomiting, regurgitation, or dysfunction. Such tests include abdominal X-rays, an esophagram or barium swallow, and fluoroscopy ( a video X-ray) to assess the esophagus in motion.
If a megaesophagus is discovered, then further testing is indicated to search for the cause of the esophageal paralysis.
Treatment of Aspiration Pneumonia in Dogs
Severely ill dogs may require hospitalization with oxygen, intravenous fluids, antibiotics and supportive care. Mildly affected pets that are well hydrated and eating properly may be treated as outpatients, with frequent follow-up examinations to monitor the progression of the infection. Additional treatments may include:
Cage rest or exercise restriction
Loosening of secretions. This can be done with a humidifier or by thumping the chest wall (coupage).
Bronchodilator therapy to help open up the airways
Bronchoscopy to remove a foreign body if present
Surgery. In a handful of cases, removal of the affected lung lobe, foreign body, or tumor may be done.
Treatment or correction of any underlying problem
Home Care and Prevention
Aspiration pneumonia, particularly of stomach contents, can be a serious, life-threatening condition. The animal may require several days in intensive care before it stabilizes, and some animals have great difficulty recovering from this condition, particularly if the underlying problem is due to paralysis of the esophagus. Once the dog is discharged from the hospital, administer all medications as directed by your veterinarian. Return for follow up examinations, blood work, and radiographs as recommended by your veterinarian.
Many times, aspiration pneumonia cannot be prevented. However, treating and controlling the underlying disorder can greatly reduce the risk of aspiration pneumonia or prevent the condition from recurring.