BOAS Surgery

That short-nosed confirmation is a growth anomaly in the bones of the muzzle created through selective breeding. This leads to abnormal (shortened) bones of the muzzle, but with the soft tissue structure that would be appropriate in long muzzled dogs like a poodle or whippet. The relative excess of soft tissue bunches up around the nose, which many people find cute or aesthetically pleasing. This excess soft tissue in the back of the mouth and nose is known to cause airway narrowing and obstruction that can impact both quality and quantity of life. 

The brachycephalic airway syndrome includes the following anatomical abnormalities:

• Narrow or pinched nostrils
• Elongated soft palate
• Everted laryngeal saccules
• Narrow windpipe
• Laryngeal collapse

Airway Compromise:

All the components of BOAS result in narrowing of the airway, either due to primary congenital anomalies the dog was born with, or secondary acquired collapse of the airway resulting in further obstruction and narrowing of the airway. 

Why is a narrowed airway a problem?

Imagine you are watering your garden with a hose. If you put your thumb over half the opening what happens? The water comes out faster, right? That is exactly what happens in a narrowed airway – the air must move faster.

What is the problem with air moving faster?

This time, imagine you have a flimsy straw, and you are drinking a milkshake. If you suck too hard, (make the air/fluid move faster) what happens? The walls of the straw collapse and you suddenly get nothing. This is what happens in our BOAS patients. The fast-moving air causes suction that works to collapse the airway. This can limit the air going into and out of the lungs. What happens when your dog suddenly doesn’t get enough air? They try harder to breathe and the harder sucking leads to even more airway collapse and eventually airway obstruction that can rapidly become life threatening. 

Prolonged respiratory distress such as excessive panting can lead to swelling of the throat and respiratory failure. Many brachycephalic dogs do not realize their limitations and will continue to push their physical activity until a respiratory crisis. Certain triggers can quickly turn mild or moderate respiratory problems into an emergency. 

These triggers include:

• Increased heat
• Increased humidity
• Excitement
• Stress
• Obesity

Surgical Treatment:

The airway compromise in brachycephalic breeds is made up of several factors that all contribute to narrowing of the airway. Several of the components of BOAS can be improved with surgery, resulting in a wider more functional airway. The wider the airway, the lower the suction caused by the fast-moving air, and the slower progression of the secondary components of the disease. This all leads to a longer and more active life.

When should surgery be performed?

The aim of surgery is to improve the primary components of the disease that the dog was born with and therefore prevent or at least slow the development of the secondary, acquired components of the disease. 

Surgical intervention should be considered preventative care, and when surgery is performed early (8 – 12 months of age) the prognosis is generally good. Whilst surgical intervention later in life is possible, most of the secondary acquired components of the syndrome do not have good surgical or medical solutions. Therefore, if we wait for these patients to become severely affected in middle age, the prognosis is poor, and they are much more likely to require critical care. 

Surgery at Moorabbin Veterinary Hospital

At Moorabbin Veterinary Hospital we offer BOAS surgery, with the procedure performed here including widening of stenotic nares, elongated soft palate thinning and shortening, tonsillectomy, laryngeal saccule removal.

If you are thinking about having BOAS surgery performed on your pet or would like an opinion on whether your pet is a suitable candidate, we recommend booking an appointment with Dr Jenny Wilsher.