Brachycephalic Obstructive Airway Syndrome (BOAS)


What is Brachycephalic Obstructive Airway Syndrome?

Certain breeds of dog have been bred to have a short face and nose, such as English Bulldogs, French Bulldogs, Pugs, Boston Terriers and Pekingese. As vets we describe these breeds as brachycephalic, which literally means “short-headed”. Unfortunately having a short head makes these breeds prone to breathing difficulties as they have too much tissue around their breathing passages. Even some breeds of cat, such as Persians, can have this syndrome.

How do I know if my pet has this?

If you have a brachycephalic breed of dog, it is most likely they will have BOAS but some dogs are worse than others. Most often you can hear that your pet has noisy breathing especially when breathing in. They may also wretch or gag while swallowing. If these dogs get very excited or it’s a hot day, we sometimes see that they become very tired and can occasionally collapse. Over time the pressure that is placed on the respiratory system causes secondary changes such as further collapse of the larynx.

How is diagnosed?

Dogs which have BOAS usually have a combination of three different things:

  • Long soft palate – the soft palate is at the back of the roof of the mouth, if it is too long then it protrudes into the airway and can reduce airflow.
  • Narrow nostrils – this can be seen very easily just by looking at their nose, you may also see that the nostrils close in whilst breathing in.
  • Enlarged tissues around the larynx – there are two areas of soft tissue just in front of the vocal cords called “saccules” which can be enlarged or even pop out of place, and reduce airflow.

Narrow nostrils can be diagnosed easily by looking, however as the other areas are right at the back of the throat it is too difficult to see with the dog awake. Therefore an anaesthetic is needed to do a full exam of the back of the throat and airways. We also normally take x-rays of the chest at the same time just to check the lower airways are fine.

Can it be treated?

If your pet is having breathing difficulties then we would recommend surgery to remove some of the excess tissue around the nose, at the back of the soft palate and throat. We monitor each dog very closely after the operation in case there is any swelling or bleeding.  Most dogs will cough a little after the surgery but it will get better over time and for the vast majority of dogs, the surgery can make a big difference to their breathing and quality of life.

Please call us on 0208 977 3955 (Teddington), 01932 229 900 (Shepperton) or 0208 390 5270 (Surbiton) if you’d like more information or advice about BOAS.

Information by Jenny Lowe, Veterinary Surgeon at Vet4life