Brachycephalic Obstructive Airway Syndrome (BOAS)

Brachycephalic obstructive airway syndrome (BOAS) is a respiratory condition that commonly affects dogs with shortened muzzles or “flat faces,” like English bulldogs, French bulldogs, pugs, and shih tzus. The shortened skull bones in these breeds result in abnormalities in the upper respiratory system, leading to breathing difficulties.

What causes BOAS?

The underlying cause of BOAS stems from the unique skull structure of these breeds, leading to a combination of several anatomical issues that obstruct airflow:

• Stenotic Nares: Narrowed nostrils may also collapse during inhalation, restricting airflow into the nose.
• Elongated Soft Palate: The soft palate (the fleshy part at the back of the roof of the mouth) can be too long for the dog’s mouth, extending into the throat and blocking the windpipe.
• Everted Laryngeal Saccules: Small pouches in the larynx (voice box) can turn inside out due to increased breathing effort, further obstructing the airway.
• Hypoplastic Trachea: In some cases, the trachea (windpipe) itself may be narrower than normal.
• Large Tongue (Macroglossia): A thick, large tongue can also contribute to overall airway obstruction.

Signs of BOAS

The symptoms of BOAS can range from mild to severe and include, but are not limited to:

• Noisy breathing (snoring, snorting, wheezing)
• Exercise intolerance (easily tired or “winded” during physical activity)
• Labored breathing (exaggerated abdominal movements or increased effort to breathe)
• Gagging, retching, or coughing, especially after drinking or eating
• Difficulty swallowing
• Disturbed sleep patterns
• Collapse or fainting, particularly after exercise or in hot weather
• Changes in bark or loss of voice
• Bluish gums (cyanosis), a sign of insufficient oxygen
• Heat intolerance (difficulty regulating body temperature due to inefficient panting)

Treatment Options for BOAS

Treatment for BOAS depends on the severity of the condition.

Mild cases may be managed with lifestyle changes:

• Maintaining a healthy weight
• Avoiding excessive heat and humidity
• Controlling activity and minimizing stress
• Using a harness instead of a neck collar to avoid pressure on the neck

Severe cases often require surgical correction. Early intervention is key for better outcomes. Surgical procedures typically include:

• Stenotic nares resection: Surgically widening the nostrils to improve airflow
• Soft palate resection (staphylectomy): Trimming the soft palate to shorten it and prevent obstruction
• Laryngeal saccule removal: Removing everted saccules that are blocking the airway
• Tracheostomy: In extreme cases of airway collapse, a temporary or permanent opening may be created in the trachea to bypass the obstruction

If your dog is experiencing a respiratory crisis, immediate veterinary attention is crucial. Treatment may include sedation, oxygen therapy, medications to reduce inflammation, or a temporary tracheostomy

Important Note: Brachycephalic dogs have increased anesthetic risks, so any surgical procedure requires careful monitoring and planning.

Understanding BOAS in Your Dog

It’s vital for owners of brachycephalic breeds to be aware of BOAS and its potential impact on their dog’s health. Early diagnosis and appropriate treatment can significantly improve their quality of life and potentially prevent life-threatening situations. If you notice any of these signs in your dog, consult your veterinarian promptly to discuss a proper diagnosis and treatment plan.