Check out our pet info
The cartilage rings of the trachea (windpipe) are shaped like the letter C lying on it’s back, with a small membrane closing over to make a complete circle. In some dogs, as they age these can lose their rigidity, making them prone to collapse.
During episodes of collapse the windpipe flattens leading to anything from mild to severe, life-threatening obstruction.
This is mainly a disease in small-breed dogs such as the miniature Poodle, Chihuahua and Pomeranian. Whilst some dogs can start to show signs at an early age, generally it is older dogs that are affected, with degeneration of the cartilages having occurred over some time.
Affected areas can be within the neck region, within the chest, or along the entire trachea.
Collapse most commonly results in difficulty breathing, cyanosis (tongue and gums turning blue), exercise intolerance and fainting. Many cases develop an intermittent “goose-honking” cough that can occur suddenly.
Clinical signs are more common when the dog is excited and breathing faster and more deeply, thereby exerting greater pressure differentials on the trachea.
Unfortunately, because collapse is intermittent, chest X-rays only demonstrate collapse in around 60% of cases, although taking many shots may increase the chance of picking up a collapse. X-rays are still compulsory however in order to rule out or confirm other heart and lung diseases as cause of the signs.
Video X-rays (fluoroscopy) show the movement of the trachea throughout the entire respiratory cycle and so are sometimes more able to pick up the collapse.
Endoscopy with a small fibre-optic viewing scope into the trachea is perhaps most reliable, allowing actual visualization and exact localization of collapse. This has some inherent risk due to partial obstruction of the trachea during the procedure and so is not always used in all patients with suspected collapse.
Medical therapy is usually effective in dogs with mild signs and may include cough suppressants, bronchodilators and antibiotics for secondary infections.
Steroid anti-inflammatories are often used to reduce swelling, whilst tranquillizers can reduce the fear and excitement that can exacerbate an episode.
Some dogs may have concurrent conditions, such as laryngeal paralysis, and may benefit from correction of these, whilst obese dogs should be placed on a diet.
Any situation that may induce panting and excitement, such as high temperatures and humidity, should be avoided if possible.
Because of the inherent risks and potential complications related to tracheal surgery, most cases are managed medically whenever possible.
Surgery is reserved for those dogs with severe collapse and little or no response to medications. As the cartilages deteriorate some dogs initially responding to medications may become resistant to them.
The purpose of surgery is to support the cartilages and maintain normal tracheal diameter.
Prosthetic rings or coils can be applied around the external surface of the windpipe, a technique mainly used for collapses within the neck region.
Expandable tubular implants (stents) inside the trachea are mainly used for collapse within the chest cavity or collapses along the entire length of the trachea. These are usually placed with the aid of endoscopy or fluoroscopy and have to be placed exactly to prevent potential complication.
Medical therapy may provide relief for the entire life of the patient. When surgery is successful it often reduces clinical signs and improves quality of life.
It should always be remembered that tracheal collapse is a progressive disease.