Figure 1. Thoracic radiographs taken at presentation.
Ask Yourself...
What is your initial assessment and treatment plan for Luna? Assume she will continue to receive supplemental oxygen.
A. Luna has aspiration pneumonia from vomiting hairballs; antibiotic therapy should be provided.
B. Luna has congestive heart failure; diuretic therapy is warranted.
C. Luna has lower airway disease; bronchodilator (albuterol or terbutaline) and glucocorticoid therapies are warranted.
D. It is unclear what Luna has developed; a keyhole lung biopsy is advised to determine the best course of action.
Correct Answer:
C. Luna has lower airway disease; bronchodilator (albuterol or terbutaline) and glucocorticoid therapies are warranted.
Luna’s clinical signs and radiograph findings were most consistent with lower airway disease (ie, feline asthma). While asthma implies reversible bronchoconstriction, some cats with lower airway disease have more inflammatory changes and less reversible airway changes.
In Luna’s case, several clues suggested that her distress was from allergic airway disease. Often, owner complaints of hairballs are in reality a cough. When owners describe their cat as trying to cough up a hairball, it is prudent to establish that hairballs are produced. This clarifies whether coughing is confused with attempts to emit hairballs.
Luna’s signs worsened after exposure to a dusty environment, although airway disease had been present for some time.
During examination, crackles and wheezes are common in lower airway disease. Adventitial lung sounds, consistent with fluid in the alveoli and airway, are not specific for congestive heart failure (CHF). In addition, cats with CHF are usually hypothermic and, subsequently, relatively bradycardic. With Luna, respiratory effort was mostly expiratory, typical of airway disease but not always appreciated at examination.
Radiographic findings consistent with airway disease include donuts and tram lines, which are supportive of bronchial thickening and hyperinflation from expiratory flow limitation. Some cats with lower airway disease also have a collapsed middle lung lobe (Figure 2).