Brachycephalic Syndrome

Also known as Brachycephalic Airway Syndrome (BAS)

What is Brachycephalic Airway Syndrome (BAS)?

Brachycephalic Airway Syndrome (BAS) is a combination of abnormalities of the upper respiratory tract in dogs that results in (partial) upper airway obstruction. While we usually think of BAS affecting dogs with short noses or “squashed faces” (English Bulldog, Pug, Boston Terrier as well as Pekinese), cats such as (Persian) can also be affected. Brachycephalic Airway Syndrome incorporates stenotic nares (small nostrils), elongated soft palate, everted laryngeal saccules, laryngeal collapse, and hypoplastic trachea; and affected dogs and cats may have any combination of these disorders. All of these conditions can be diagnosed from a simple clinical examination, thorough oral examination (sedation is required) and chest X-rays.

What should I look for?

Clinical signs may include noisy breathing, snoring, exercise intolerance, gagging, regurgitation, vomiting, fainting and difficulty breathing. Many animals with BAS cannot tolerate the heat. In mild forms, or in the early stages of BAS, animals can be effectively managed with weight loss, exercise restriction and housing in a cool environment. However, if animals are distressed and having difficulty breathing, they may need to be hospitalized and provided with oxygen, sedatives, and anti-inflammatories. Some dogs will require a tracheostomy (breathing tube) in an emergency.

If you notice your pet is snoring loudly, tiring easily after exercise, coughing, retching or gagging freguently or panting loudly; your pet may have clinical brachycephalic airway syndrome. If you have a pet that you believe may have BAS, please talk to a veterinarian about preventive treatments (medical or surgical) to ensure your pet can breathe easily!

If your pet has difficulty breathing, is gasping for air, or has dark red or purple tongue you should go to an emergency room ASAP!

How can surgery help my pet?

Most brachycephalic animals are born with either stenotic nares or a hypoplastic trachea (or both!) and during development, these conditions lead to elongation of the soft palate, eversion of the laryngeal saccules and ultimately laryngeal collapse. Therefore, if caught early enough, we are able to delay or stop the progression of clinical signs associated with BAS. Only stenotic nares, elongated soft palate and everted laryngeal saccules are amenable to surgical correction, but most animals are much more comfortable after surgery for these problems.
Most animals stay in our 24-hour ICU the night after surgery, so that we can monitor them closely after anesthesia and surgery. Complications from surgery are not common, but can include a change in voice/bark, pneumonia, nasal reflux/discharge and dehiscence of the sutures.

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