Tracheal Collapse and the Use of Intratracheal Stents
Dr. Jennifer Clooten
Tracheal collapse is a common disorder in dogs. It is a progressive, degenerative disease of the cartilage rings in which hypocellularity and decreased glycosaminoglycan and calcium content leads to a dynamic airway collapse during respiration. It is typically seen in middle aged to older small and toy breed dogs. This disease particularly affects Toy Poodles, Yorkshire Terriers, Chihuahuas, Pomeranians, Maltese, and Pugs. The collapse can affect any part of the trachea (cervical and/or intrathoracic) and even concurrent mainstem bronchial collapse can be commonly found as well. Clinical signs of tracheal collapse range from a mild intermittent “honking” cough to severe respiratory distress and cyanosis. Underlying conditions such as bronchitis, bronchopneumonia, mitral valve regurgitation, obesity and hyperadrenocorticism may exacerbate signs of tracheal collapse and should be managed accordingly.
The majority of dogs diagnosed with tracheal collapse respond well to medical management. The goal of medical management is to suppress the cough and reduce tracheal inflammation. Various treatments such as corticosteroids, antitussives, sedatives and bronchodilators are commonly used. Interventional or surgical treatment should be considered only in those patients who fail medical management. Surgical placement of extraluminal prosthetic rings for dogs with extrathoracic tracheal collapse is a good option; however, surgery is not feasible for the intrathoracic trachea. The combination of surgical risks and inability to adequately treat intrathoracic tracheal collapse has led to the evaluation of minimally invasive techniques similar to those used in human medicine.
Intraluminal tracheal stenting is minimally invasive, is associated with shorter anesthesia times, and provides access to the entire intrathoracic portion of the trachea. The extrathoracic trachea can be stented as well intraluminally. Complications that have been reported with surgery for tracheal collapse, such as laryngeal paralysis, tracheal necrosis, incisional pain, and seroma formation can be avoided with intraluminal stenting. Stenting can significantly improve the patient’s quality of life when medications alone are no longer adequate in controlling the clinical signs associated with tracheal collapse. Clinical improvement has been reported in 75%-90% of dogs treated with self expanding intraluminal metallic stents. Although rare, complications associated with intratracheal stents can include stent shortening, granulation tissue formation, bacterial tracheitis, progressive tracheal collapse adjacent to the stent, stent fracture, and stent migration.
The internal medicine service at VMS is now offering intratracheal stenting. Patients typically will undergo an initial evaluation and consultation with one of our internists. If a patient is determined to be a good candidate for stent placement, bronchoscopy will be performed to collect samples for cytology and culture and to evaluate extent of collapse. Stent placement, depending on the individual patient, may or may not be performed concurrently with initial bronchoscopy. Please do not hesitate to contact us if you would like to refer a patient for stenting or if you have any questions about the procedure.