BOAS – Brachycephalic Obstructive Airway Syndrome
Some breeds of dog, because of the shape of their head and muzzle, may face difficulties in breathing and have reduced exercise tolerance. They are called brachycephalic – meaning “short headed”. Common breeds to be affected are English and French Bulldogs, Pugs, Shih-Tzus, Pekingese.
Respiratory Function Grading Scheme:
The Kennel Club and University of Cambridge’s Respiratory Function Grading Scheme assesses Bulldogs, French Bulldogs and Pugs for BOAS. Advising owners if their dog is affected by BOAS and giving guidance on breeding. Kasia Atmaca MRCVS is an appointed and approved assessor for the region and appointments can be made by calling our East Grinstead practice.
Your dog should be:
- Over 12 months, and assessed every 2 years
- French Bulldog, British Bulldog or Pug
- If KC registered please bring your documents
BOAS is a combination of three conditions:
- Stenotic nares (very narrow nose)
- Elongated soft palate (inside mouth between the entrance to trachea and oesophagus)
- Everted laryngeal saccules (tissue around larynx inside mouth)
These three issues combined, or often even one of these, may cause significant problems whilst breathing. The air flow can be limited by the narrow nostrils or by the soft palate and laryngeal saccules obstructing the airways.
Affected dogs can also suffer from a narrow trachea, laryngeal collapse, laryngeal paralysis or hiatal hernia (a part of the stomach sliding into the chest). These patients will also have a higher risk of complications related to general anaesthesia.
Signs to watch out for:
Noisy breathing is one of the most common signs that we need to be cautious about and unlike some owners believe – it is not normal for these breeds. Problems with taking a deep, noise-free breath during rest or gentle walking are a concern. If an affected dog is stressed or worried, is in pain, gets too hot or is just exercised more than usual, the risk of inadequate ventilation is very high.
If you see the gums and tongue changing colour from pink to purple/blue or your dog has problems with taking a calm breath in and out, this is an emergency.
Coughing and occasional vomiting can increase the risk of aspiration pneumonia (infection caused by inhaling food or vomit), which is a severe condition, and obesity lowers the tolerance of limited breathing.
Sleep apnoea (prolonged time between breaths during deep sleep) can be dangerous and is often a sign of problems.
How can we diagnose it?
Stenotic nares can be observed easily during a clinical examination. If we want to assess the soft palate and laryngeal saccules, your dog will need a general anaesthetic; to examine the trachea and check for hernia, we use endoscopy equipment (long camera).
Elongated soft palate** Post surgical soft palate**
Treatment we can provide:
These abnormalities should be treated to increase the comfort of the affected dog. These are not only cosmetic changes, but make a big difference for a patient who cannot otherwise enjoy sunny weather or a run in the park.
Under general anaesthesia:
- We can assess the airways with the camera (endoscopy) and make sure no other concerns are present.
- We can take an x-ray to measure the diameter of the trachea (windpipe).
- We assess and surgically shorten the soft palate, so that it doesn’t obstruct the entrance to the airways (soft palate reduction).
- We correct the nares by surgically widening them, which results in immediate increase in air flow (rhinoplasty).
- We can surgically remove everted laryngeal saccules (laryngeal saccule removal).
If we feel that a collapsing or very narrow trachea is present we may offer referral for a tracheal stent procedure.
Recovery and post-surgery care:
The patient’s recovery must be monitored very closely especially for the first 72 hours, to look for inflammation or stress (as after any surgery in brachycephalic patients). Usually, if we don’t encounter complications, but we often hospitalise patients overnight for close observation, otherwise they can go home the same or next day and healing is fast and relatively pain free.
Although this kind of surgery carries risks (like all procedures carried out under general anaesthesia), the beneficial effects are greatly appreciated by the dog and the owners, once they can breathe freely and enjoy a better quality of life.
* Pictures taken from www.vet.cam.ac.uk
** Pictures taken from www.fitzpatrickreferrals.co.uk