Aspiration Pneumonia | Dr. Justine Lee
If your dog or cat was just diagnosed with aspiration pneumonia, read on! This is a potentially life-threatening emergency that warrants an immediate trip to your veterinarian or emergency veteriarian for oxygen therapy and treatment.
Aspiration pneumonia is the condition when gastrointestinal contents have been inhaled into the lungs. This results in a secondary inflammation and infection of the lung. Due to this inflammation, excessive fluid and mucus accumulates within the lower airway, causing difficulty breathing.
Dogs that develop aspiration pneumonia typically have a history of: 1,2
- Recent anesthesia or sedation
- A diagnosis of an underlying medical condition that predisposes the dog towards aspiration
- Neurologic problems
Medical conditions that make a dog more likely to aspirate vomitus into their lungs include: 1,2
- Laryngeal paralysis
- Persistent right aortic arch (seen in puppies)
- Congenital esophagus problems
- Gastrointestinal disease
If your dog had recent sedation or anesthesia for surgery, has an underlying medical condition that predisposes it to aspiration, or gets sick after vomiting, he or she may have aspiration pneumonia. Clinical signs of aspiration pneumonia include:
- Not eating
- An increased respiratory rate
- Exercise intolerance
- Open mouth breathing
- Noisy or wet breathing
- Blue-colored gums
- Stretching of the neck out to breath
The diagnosis of aspiration pneumonia in dogs typically starts with a thorough physical examination by your veterinarian (including careful auscultation with a stethoscope for abnormal lung sounds). Additional tests to diagnose aspiration pneumonia include:
- Chest x-rays
- Abdominal x-rays (to look for the cause for the vomiting)
- Baseline blood work to make sure the kidneys, liver, and other organs are working appropriately and to see if the white blood cell count is elevated
- Pulse oximetry or an arterial blood gas to measure the oxygen level within the lungs or blood.*
* NOTE: A normal pulse oximetry reading should be > 95%. Anything < 92% requires oxygen therapy, as it means the blood oxygen saturation is very low!
Sometimes, a transtracheal wash or endotracheal lavage are necessary to diagnose the underlying bacterial infection within the lung. This is a “fluid wash” where fluid is flushed into the lung and aspirated back for culture testing. This is often important to help rule out other
causes of pneumonia, such as other bacterial causes (e.g., kennel cough pneumonia secondary to Bordatella bronchiseptica), fungal causes (e.g., Blastomycoses), or even cancer.
If you notice any of the clinical signs of aspiration pneumonia, immediate treatment at your veterinarian is necessary. Treatment includes oxygen therapy, intravenous (IV) catheter access, IV fluids, and IV antibiotics. Additional therapy may include anti-vomiting medication (e.g., maropitant), nebulization and coupage, and lung expanders (e.g., bronchodilators). Once your dog is more stable, diagnostics such as blood work and x-rays should be performed.
Treatment should not include diuretics (e.g., water pills) that can dehydrate the patient or cough suppressants (which can prevent the pus in the lungs from being coughed up). Also, drugs that suppress the immune system (e.g., cyclosporine, prednisone) typically should not be used as it can prevent the body from fighting the infection within the lung.
Once a dog can breathe without the support of oxygen therapy, treatment at home includes antibiotic therapy for 3-5 weeks. Frequent recheck veterinary examinations should be performed to make sure the pneumonia is resolving – this will include recheck chest x-rays approximately once a week for several weeks. Oral antibiotics should be continued for one week past the resolution of abnormal x-ray patterns.
Thankfully, the prognosis for aspiration pneumonia is good, with an average 77-81.6% survival rate.1,2 However, this can be a significant complication of even elective surgery, and can add significant costs due to hospitalization and treatment.
- Kogan DA. Johnson LR, Sturges BK, et al. Etiology and clinical outcome in dogs with aspiration pneumonia: 88 cases (2004-2006). J Am Vet Med Assoc 2008;233:1748-1755.
- Tart KM, Babski DM, Lee JA. Potential risks, prognostic indicators, and diagnostic and treatment modalities affecting survival in dogs with presumptive aspiration pneumonia: 125 cases (2005-2008). J Vet Emerg Crit Care 2010;20(3):319-329.
As previously published on www.PetHealthNetwork.com.
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