The trachea is a tube that transports air from the nose and throat to the tiny air passages leading to the lungs. The trachea is kept open with the support of small C-shaped rings of cartilage, with the opened sections facing upwards. The dorsal membrane is tissue that lines the upper opening of the C-rings.
Collapsing of the trachea is caused by constriction of the trachea opening when the affected dog breathes.
Trachea collapse is a chronic, progressive disease that predominantly affects certain small breeds of dogs such as Yorkshire terriers, Chihuahuas, Pomeranians, Miniature poodles and Maltese, Pugs, Lhasa apsos, and Shih Tzus along with other toy breeds.
Tracheal collapse can be either congenital, meaning it’s been there since birth, or it can be acquired.
When the disease is congenital, the cartilage rings have either not fully developed at birth or they deteriorate and gradually mutate from a rounder C-shape to a flatter U-shape. The cartilage rings gradually get flatter as the dorsal membrane expands, until the trachea gives way and collapses. The dog is then left having to try inhale air through what can be described as a closed straw. This can be caused by deficiencies in calcium, chondroitin, glycoproteins and glycosaminoglycans in certain parts of the cartilage rings.
When tracheal collapse is acquired, it’s often triggered by chronic respiratory disease, heart disease or Cushing’s disease.
When the dog breathes air, the trachea cavity begins narrowing and this can affect the section of the trachea in either the neck or the chest. Trachea collapse in the neck occurs when the dog inhales and collapse of the trachea in the chest occurs when the dog exhales. Often, the collapse implicates the bronchi that ultimately sends air to the lungs, leading to critical obstruction in the dog’s air passage.
Tracheal collapse is commonly caused by cases where dogs are obese.
An early sign indicating the onset of trachea collapse can be an abrupt dry coughing spell resembling that of a honking sound that gradually develops into a more persistent cough when placing pressure on the dog’s trachea. Progression of the disease can lead to exercise intolerance, respiratory distress along with retching when eating or drinking.
Symptoms associated with trachea collapse are intensified by exercise, heat, excitement or obesity.
When dogs appear to make a wheezing sound when inhaling, they may be suffering from both tracheal collapse as well as laryngeal paralysis.
Other associated symptoms appear in the form of:
- breathing difficulties
- unusually rapid breathing
- unusual breathing sounds
- resistance to routine exercises
- blue coloured membranes
- sudden loss of consciousness
- constant laboured breathing can lead to secondary heart disease
The narrowing of the tracheal cavity can sometimes be observed on a standard X-ray, however a moving X-ray, called a fluoroscopy or alternatively a bronchoscope, better enables the vet to accurately scrutinise the trachea whilst the dog inhales and exhales.
An endoscopy provides the vet with the most efficient way to view the inside of the airway by using a little camera to observe the inside of the trachea. The vet can simultaneously take tissue samples of the trachea for culture and sensitivity testing or additional analysis.
An echocardiogram may be recommended in cases where there is concern about the functioning of the heart.
Tracheal collapse can often be confused by any disease related to the upper or lower air passages such as a foreign object trapped in the air passage, laryngeal paralysis, an elongated soft palate, trachea or lung infection, heart failure, tumours or even polyps. It’s therefore important that your vet gives you a conclusive diagnosis.
Because coughing triggers more coughing as it agitates the air passages, it’s imperative to bring the coughing cycle to an end.
Approximately 70% of dogs with mild to moderate cases can be treated successfully with cough suppressants, antispasmodics, bronchodilators as well as sedatives to ease coughing spasms and any anxiety associated with breathing difficulties.
Cartilage building supplements can also be administered to sustain the tracheal cartilage’s structural integrity.
Any identified infection will be addressed immediately, whilst obese dogs will be promptly put on a strict eating plan to lose weight.
In more serious instances where dogs don’t respond favourably to medical treatment, surgery may be required. This is a highly-specialised procedure and depending on whether the tracheal collapse occurs in the neck or the chest, plastic rings are either surgically inserted around the inside of the trachea or a stent is surgically placed in the trachea to hold it open. Ensure your vet is extensively experienced in performing this intricate procedure, as it brings with it potential complications.
Serious symptoms and breathing difficulties render hospitalisation a necessity where dogs will be given oxygen therapy. Sedation may also be required to alleviate any associated suffering and to prevent any resistance from the dog when administered treatments. Until the dog is stabilised, they must be kept as still as possible.
Whilst recovering, patients should be resting as much as possible. Gentle exercise and a healthy diet are highly recommended to support weight loss for the long-term maintenance of your pup. Consult your vet about a suitable eating plan to assist your dog in reaching their ideal weight.
Avoid getting your dog too excited as this may exasperate an already comprised breathing problem.
Use a harness as opposed to a collar around the neck as any undue pressure on the trachea will further contribute to breathing difficulties.
Ensure your dog’s environment is free from smoke and environmental impurities.
With the appropriate treatment, weight and management plans in place, tracheal collapse can be managed effectively and the possibility of remission from the disease is positive.
Written for inFURmation
by Taliah Williamson
Disclaimer: The information produced by Infurmation is provided for general and educational purposes only and does not constitute any legal, medical or other professional advice on any subject matter. These statements are not intended to diagnose, treat or cure any disease. Always seek the advice of your vet or other qualified health care provider prior to starting any new diet or treatment and with any questions you may have regarding a medical condition. If you suspect that your pet has a medical problem, promptly contact your health care provider.