by NW Vet Staff
What is brachycephalic syndrome?
The full name of this disorder is brachycephalic airway obstruction syndrome (BAOS). Brachycephalics are those breeds which have a comparatively short head. Because of their anatomy, virtually all dogs of these breeds have some degree of increased work associated with breathing from the time they are born. Many have varying degrees of obstruction to their airways, which causes signs ranging from noisy breathing to collapse.
The most common anatomical features that lead to the respiratory difficulties typical of these breeds, include an elongated and fleshy soft palate, and narrowed nostrils. Many affected dogs also have changes to the larynx (everted laryngeal saccules) and a relatively small trachea (hypoplastic trachea).
Selection for exaggerated features has resulted in the respiratory difficulties in these breeds. For example breed standards for the English bulldog specify that the face should be very short, as should the distance between the tip of the nose and where it is set deep between the eyes. It is hardly surprising that this leaves little room for the structures involved in normal breathing.
These problems are generally most common and severe in the English bulldog. Other brachycephalic breeds in which this syndrome is found include the pug, Boston terrier, Pekingese, Cavalier King Charles spaniel, Chinese shar-pei, French bulldog, Lhasa apso, and shih tzu.
Problems associated with this syndrome range in severity, with most brachycephalic dogs snuffling and snorting to some degree. Some will have no further difficulties, but many will have problems such as increasingly noisy breathing, coughing and gagging, fainting or collapsing episodes, and a decreased tolerance for exercise (ie. they tire easily). Over the long term, this also puts an increased strain on the heart. Some dogs, such as English bulldogs, may have frequent episodes of sleep-disordered breathing. It is important to keep your dog from becoming overweight, as this will worsen his or her respiratory difficulties in the long run.
Overheating is especially dangerous in these breeds, because increased panting (the normal mechanism for cooling in dogs) can cause further swelling and narrowing of the already constricted airways, which will increase your dog's anxiety. Excitement, exercise, or warm weather (and especially a combination of these factors) can trigger this vicious cycle. These dogs can also have gastrointestinal problems, because of difficulties coordinating swallowing when they are working so hard at breathing. This can result in vomiting ar gagging because of swallowing so much air, or aspiration pneumonia, because of breathing in saliva or food particles.
These problems are usually evident from a young age. If your dog has respiratory difficulties, your veterinarian may discuss this syndrome with you as part of a regular visit, or you may bring your dog in because of an episode such as collapsing after exercise.
Because some changes in anatomy are common to all dogs of these breeds, diagnosis is really a question of the degree of abnormality. The overlong soft palate is best examined under general anesthesia. It is important that brachcephalics are cared for delicately under sedation. We set up a specific plan catederd to the needs of the breed and specific make up of your individual pet. Ask us if you think your pet may need an evaluation, we can set up a meeting with one of our veterinarians to walk you through our process.
How is brachycephalic syndrome treated?
Medical treatment (oxygen therapy, corticosteroids) can be used for short term relief of airway inflammation. Surgery is required where severe anatomic faults interfere with breathing. Most commonly this involves removal of some of the excess fleshy soft palate, and widening of air passages at the nostrils. The veterinarians and care team at both of our Everett and Seattle locations are trained specifically to work with all brachycephalic breeds. Ask us if you have any treatment or surgery related questions or if you would like to set up a consultation.
Northgate Veterinary Clinic - Seattle (206)363-8421
Broadway Animal Hospital - Everett (425)252-8266