Before studying the repercussions of tracheal collapse, it is important to understand the structure and functions of this part of canine anatomy.  The trachea is the airway tube which connects the larynx to the main-stem bronchi in the lungs.
        Structurally, the trachea consists of  "C" shaped cartilage rings and flexible tissue, covered by a specialized lining.  This lining has cells with tiny hair-like projections (cillia).  The primary function of the cillia is the removal of mucus, inhaled particles and inhaled bacteria.  Between the movement of the cillia gathering this debris and the cough reflex, the trachea serves as a filter screening this debris from reaching the lungs.
        Tracheal collapse is the name given to a syndrome in which the rigid structure of the trachea becomes weakened.  This weakened area collapses due to external and/or internal pressure created during activity, thus interfering with normal respiration.  The weakened area becomes irritated.  Since coughing and respiratory exertion can cause further irritation, clinical signs will worsen and the condition can become self perpetuating.  Tracheal collapse may occur alone or in association with another airway disorder (most often chronic bronchitis).
        A chronic "honking" cough can be an indication of this condition.  In some cases the cough can become so severe that the animal behaves as though there is something caught in its throat.  Other indications of this disorder include; breathing difficulty, tiring easily and exercise intolerance.
        Mild cases often respond well to cough suppressants and stress reduction (reduce intense exercise and excitement).  These dogs can live long and healthy lives.  In more advanced cases surgical correction may be necessary.  In cases of combination airway disorders, treatment of the contributing disorders may be necessary before treating the tracheal collapse.