Spotlight on Aspiration Pneumonia

Medical articles
dog in grass

It happens to most pet parents at least once. You leave the room for a mere moment and when you return Fido or Fluffy have their head in the garbage or the Easter basket inhaling things they definitely shouldn’t. Many pet parents wrongly assume that inducing vomiting at home ASAP is the best course of action, but this is simply not true. Inducing vomiting at home should be performed only when warranted because of the dangers that go along with it.

What is aspiration pneumonia?

One of the most dangerous undesirable consequences that can results from induced vomiting gone awry is aspiration, or inhalation, pneumonia. In its simplest terms, aspiration is the act of taking foreign material from the upper GI tract into the lungs. The course that follows is determined by the quantity and nature of the aspirated material, the frequency of aspiration, and the host factors that predispose the patient to aspiration and affect the response. Aspiration pneumonia results from the inhalation of liquid, food, or bacteria into the respiratory tract (lungs). Most often the onset is rapid, but sometimes the signs are chronic and insidious.

Causes

There are several causes of aspiration pneumonia. Swallowing disorders or inability of the larynx to close during swallowing are two neurologic or muscular problems that can lead to aspiration. Dilation of the esophagus (megaesophagus), secondary regurgitation, and aspiration during vomiting are other potential causes. Animals that are under general anesthesia, recumbent for prolonged periods, profoundly depressed, or comatose are predisposed to aspiration. Attempts to force your pet to take pills, food, or liquid can sometimes overwhelm the protective reflexes of the larynx and result in aspiration pneumonia.  Even vets can set the stage for aspiration. Accidental passage of a stomach tube or administration of barium and other substances into the airway can also cause pneumonia. You should never try to induce vomiting in a pet that is not 100% conscious and upright.

Symptoms

When a pet aspirates, usually a sudden onset of coughing, panting, and difficulty breathing are noted. Later pets may develop a fever. Purple or blue gums caused by lack of oxygen may accompany these signs. Affected animals are lethargic and may not eat in cases that are slower to develop. Progressive respiratory impairment can occur and can be life-threatening.

Diagnosis

Diagnosing aspiration pneumonia is not the most intellectual challenge your vet has ever faced. The history and sudden onset of signs alone are often suspicious for aspiration pneumonia. Routine laboratory tests and chest x-rays are a reasonable and good amount of diagnostic information to gather, aiding your vet in the investigation of potential causes of a cough or respiratory distress. Chest x-rays may show lungs changes consistent with aspiration pneumonia. Animals in severe distress often require therapy before other tests can be performed so be patient if your vet wants to move straight to therapy before confirming a diagnosis. Advanced work-ups involving diagnostics such as a transtracheal wash or bronchoscopy are the exception and not the rule.

Treatment

Most affected animals require hospitalization for aggressive therapy. In severe cases, treatment for shock, supplemental oxygen, and ventilation may be needed. Bronchodilator drugs may decrease spasms in the lower respiratory tract. Antibiotics are often given, either before or after culture results are known because time is of the essence when dealing with pneumonia of any type.

Nebulization using a humidifier may be tried in some cases, either at home or at the hospital. Chest coupage, which is gentle but forceful thumping on the rib cage, may help loosen secretions in the respiratory tract. If your pet is ill enough to warrant coupage therapy, it will probably be hospitalized. Rarely, lung changes become so severe and chronic that surgical removal of the diseased lung is necessary.

Intensive continuous monitoring is needed while the pet is hospitalized. Severely ill patients may require supplemental 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. Chest x-rays are an excellent way to evaluate response to therapy and are usually taken every 24-48 hours.

Prognosis

After the pet is released from the hospital, the owner usually continues antibiotics at home for at least another week. Chest x-rays are often taken again in 5-7 days. One of the reasons for treatment failure is noncompliance by owners; that is, failure to administer the medications as directed and follow the doctor’s orders.

When aspiration pneumonia is recognized and treated early, most pets make a complete recovery. If the underlying condition cannot be treated successfully, aspiration pneumonia is not likely to resolve. Aspiration pneumonia that involves a large portion of both lungs or aspiration of particularly toxic material can be fatal.

Aspiration pneumonia can be a serious, life-threatening condition. Should your pet develop this condition, you are probably looking at leaving him or her with your veterinarian for several days of regular monitoring and intense treatment. Some pets have difficulty recovering from this condition despite the best of care. Before you assume you should induce vomiting in your pet at home, ask your vet o before you risk this potentially fatal condition. The resulting aspiration pneumonia may be more harmful than what your pet ingested at in the first place.