Tracheal collapse is a fairly common complaint, especially in small breed dogs, and is usually associated with cough or other, more serious respiratory problems. While the severity of the collapse itself will depend on your dog’s genetics, it’s important to know the warning signs, and take action early.
A word about the trachea…
The trachea is basically your dog’s windpipe, which is a tube connecting the nose and mouth to the throat and the lungs. It’s basically what allows your dog to breathe. The trachea, when healthy, is supposed to look like a rigid tube, made up of muscle that connects various cartilage rings (well, semi-circles, really). These cartilage rings are rounded out towards the animal’s front, with the ends on the animal’s back, connecting to the tracheal membrane.
The trachea works as a pipeline that supports the movement of the diaphragm to permit air into and out of the lungs. While much of the trachea is located inside the throat, there is also a portion extending into and outside of the dog’s chest.
What is tracheal collapse? And why does it happen?
Breathing depends on the trachea maintaining a rigid, tube-like shape. Tracheal collapse occurs when the C-shaped cartilage rings lose their shape, and can no longer maintain the tube’s tightness. When the cartilage becomes spongy, the tube itself becomes floppy and collapses, inhibiting the air supply. When the dog tries to breathe, the collapsed membrane brushes against the tracheal lining, which results in a telltale cough, but can also have more serious consequences, like trouble breathing, and severe discomfort.
Most dogs suffering from tracheal collapse enter a vicious cycle – the coughing and difficulty breathing generate anxiety, which leads to panting, and short, rapid breathing, which in turn exacerbates thoracic distress, and in turn causes more anxiety and rapid breathing.
The collapsed trachea also causes inflammation, which in turn leads to increased secretion in the tracheal tract, and that worsens the dog’s cough (which leads to more inflammation).
Tracheal collapse may occur inside the chest (intrathoracic), outside (extrathoracic), or across its full length.
While it’s likely for small dogs (poodles, Yorkshire terriers, Pomeranians, etc.) to develop tracheal collapse at any age, it usually becomes worse towards middle age. Usually, the culprit is a hereditary defect that causes the C-shaped cartilage to become flattened, and the trachea to collapse. As with many conditions, tracheal collapse is aggravated by other conditions, such as:
- Enlarged heart (in this case, the heart can press of the intrathoracic trachea);
- Anesthesia that uses an endotracheal tube;
- Respiratory infections (such as kennel cough);
- Airborne respiratory irritants (such as cigarette smoke, dust, harsh chemicals, etc.);
The good news is that if it’s determined that one of the above secondary factors is what’s worsening the tracheal collapse, and difficulty breathing, the solution may just be removing the secondary factor, to alleviate symptoms.
A 2006 study suggested that dogs with tracheal collapse also had a higher risk of developing liver disease.
How is tracheal collapse treated?
Rather than being treated, the focus with tracheal collapse is on managing the condition and alleviating the symptoms as best as one can. As mentioned, if your dog’s tracheal collapse is worsened by any of the above secondary factors, you should try to remove said factor – weight loss programs, air filters, and the like can seriously improve the quality of your dog’s breathing.
You might also benefit from introducing cough suppressants into your dog’s routine, particularly if his cough is getting in the way of activities. Medicine such as hydrocodone, tramadol, and butorphanol can act as efficient cough suppressants that alleviate your dog’s reaction to tracheal collapse.
In some cases, your vet might also prescribe inhalers with corticosteroids (such as prednisone) to clear up excessive mucus secretion. However, these may only be used sporadically, since corticosteroids are well-known for creating addiction.
Your vet may also recommend airway dilators, like terbutaline or theophylline. While these don’t affect the trachea itself, they work to dilate lower airways, which in turn relieve the pressure in the chest while breathing and can maintain the trachea.
While tracheal collapse is disheartening, know that it’s not all bleak. Studies have shown that in 100 dogs with tracheal collapse, 71% responded well to the removal of secondary factors, and improved.
Surgery for tracheal collapse?
If the medicine used to treat tracheal collapse is deemed inefficient, your vet might deem surgery necessary. Depending on your dog’s condition, this may either involve the placement of steel tracheal rings inside the trachea to replace the weakened, collapsed cartilage; or the placement of a cylindrical mesh prosthesis (aka a trachea stent).
Although surgery can result in a favorable outcome, it will not completely remove the need for medication to suppress the coughing.
How do these work?
In cases of tracheal collapse that occur outside the chest, ring prosthesis can be highly effective, with an improvement rate of 75%-85%. However, as with any surgery, tracheal ring prosthesis is not flawless and may result in death (5%), permanent tracheostomy (10%), and laryngeal paralysis (11%).
The mesh stent is considered a better option. A self-expanding, cylindrical stainless steel prosthesis placed inside the trachea, to support breathing, during an initial study, saw a 96% success rate. Post-op, 30% of the dogs involved were symptom-free, 61% saw serious improvement, while only 4% still experienced symptoms.
While surgery can provide relief, it is not for mild cases of tracheal collapse, and you should discuss with your vet the best course of action for you.