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Tracheal collapse The trachea is the windpipe leading to the lungs. It consists of numerous C-shaped cartilage rings with the gap bridged by tracheal muscle. The structure is semi rigid which allows alteration of its diameter but the cartilage prevents complete collapse. In dogs suffering from collapsing trachea a flattening of the structure occurs during inspiration. It is almost invariably seen in small breeds of dogs such as Yorkshire Terriers, Pomerians and Minature poodles. The severity of the condition depends on the degree of collapse and on the presence of concurrent disease. If the condition is severe it will present in the young animal and an attempt at surgical correction may be required, in mild cases it may cause no problems until middle or old age. All cases present with an initial dry hacking, or 'honking' cough, respiratory difficulty will be present to some degree, worsened by exercise. The worst cases will collapse and faint, the condition is worsened if the animal is overweight. Coughing can be easily elicited by palpating the trachea and in some animals a flaccid trachea can be palpated. Diagnosis can be confirmed occasionally by X-rays, or when available flouroscopy. These will demonstrate a narrowing of the trachea at some point during the respiratory cycle. The difficulty with X-rays is exposing the film at the same time as the trachea is narrowed. Flouroscopy is a form of continuously exposing an x-ray and viewing the tissue movement on a monitor. The condition is progressive with an insidious onset then gradual deterioration. Treatment varies with the severity of the clinical signs. Surgery is only necessary in severe conditions in the young animal, various techniques have been described but outcome is variable and success cannot be guaranteed. Treatment in mild cases centers around dieting to reduce or avoid obesity, use of a halter rather than a collar and avoiding excessive exercise. Medical therapy is often only palliative and involves bronchodilators, antitussives, corticosteroids, and antibiotics (only if secondary infections). There is currently no treatment which allows resolution of the problem, in severe cases the long term prognosis is guarded. |
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