Tracheal Collapse
by Vickie Halstead RN, CVNS, CCRN, CEN, LNC
Tracheal collapse disease occurs mostly in older small breeds of dogs, but occasionally in young dogs as an inherited disease. This condition does occur in Bichons, but is not common.
The trachea (windpipe) is a tube of flexible tissue that connects the larynx (voice box) in the throat to the lungs, which allows air to enter and leave the lungs. Rings of cartilage maintain the trachea in an open position, but with this disease those rings are weakened and the trachea can collapse while breathing. At the bottom of the trachea, where it divides into the right and left bronchi (smaller airways) that lead to each lung, is an area called the carina where the cough reflex exists. Coughing occurs if there is stimulation to the carina by excess mucus, tubes, or tracheal collapse. In addition to being a breathing tube, the trachea is lined with cilia that move mucus and inhaled debris up and out of the trachea, which can be impaired with this condition due to the deformed trachea. The trachea, cilia, and cough reflex serve as a filter to prevent mucus and debris from reaching the lungs, so malfunction of this mechanism can lead to respiratory infections.
The major clinical sign of this disease is a chronic honk-type of cough that is worse with stress, exertion, inhaled irritants (cigarette smoke or dust), hot and humid weather, and drinking water. Also the dog may exhibit a rapid respiratory rate, excessive panting, reverse sneezing, exercise intolerance, and frequent respiratory infections. Clinical signs worsen as the disease progresses.
Tracheal collapse needs to be differentiated from another disease that may cause similar symptoms, laryngeal paralysis (LP), which researchers suggest may affect 25% of dogs, mostly larger breeds. LP is a condition in which the muscles surrounding the voice box (larynx) do not function properly causing coughing while drinking, excessive panting, exercise intolerance, voice changes, and loud breathing.
Treatment for mild cases of tracheal collapse is aimed at early antibiotics for respiratory infections, weight loss if obese, low-stress routines, avoiding situations that trigger episodes of coughing, moderate exercise, using a harness instead of collar which can press on the trachea, and avoiding cigarette smoke in the house. During more severe episodes some drugs that may be helpful are steroids, bronchodilators (they dilate the airways), cough syrup, and low-dose sedatives. If your dog seems to be in extreme respiratory distress, seek emergency veterinary care immediately. Surgical splinting of the trachea can be done for more advanced cases, but this is a major surgery that may have complications. Some universities are inserting a stent to keep the trachea open, which is a smaller surgery.
Research for this article includes:
The Merck Veterinary Manual
The 5 Minute Veterinary Consult by Larry Tilley& Francis Smith
Textbook of Medical Physiology by Arthur Guyton & John E. Hall
The Dog Owner’s Home Veterinary Handbook by James Griffin & Liisa Carlson
Jeff Grognet, ‘Laryngeal Paralysis More Frequent Than Commonly Thought’, AKC Gazette, December, 2006.