Brachycephalic Obstructive Airway Syndrome (BOAS), is a combination of abnormalities affecting short faced dogs and cats, known as brachycephalic breeds. Although these animals are very cute and loveable, BOAS effects the quality and length of life of affected breeds. The syndrome is the result of the deliberate breeding for shorter faced animals which has caused the detrimental side effect of defective airways in dogs and cats. Some notable brachycephalic dog and cat breeds often include French Bulldogs, Pugs, English Bulldogs and Persian cats.
The four main classifications of BOAS include
- Stenotic nares: Narrow or even closed nostrils and nasal passages.
- Elongated soft palate: Abnormally long soft tissue palate relative to the length of face which results in the blockage of the windpipe during breathing.
- Everted laryngeal saccules: Normal, blind, sack like pits that can be turned inside-out from excessive negative pressure on the airways. Once everted, laryngeal saccules contribute to the obstruction of airways. Brachycephalic animals are not born with this abnormality.
- Hypoplastic trachea: Abnormally narrow windpipe, more often overrepresented in bulldogs.
The classic ‘snore’ or ‘grunt’ seen in brachycephalic breeds is evidence of the abnormalities of BOAS outlined above.
The main health concerns for brachycephalic breeds diagnosed with BOAS include increased risk of overheating, Increased pressure and risk of airway collapse (both windpipe and lung airways) and a decrease in oxygenation to vital organs (such as the brain) - all secondary to the increased airway obstruction. Due to the chaotic and turbulent oxygen exchange in brachycephalic breeds, another associated risk is aspiration pneumonia (food, water or saliva going down into the lungs). In addition to airway disease, brachycephalic breeds are pre-disposed to certain gastrointestinal diseases causing regurgitation, which can further complicate and increase the risk of aspiration pneumonia.
Treatment and prevention of brachycephalic airway syndrome in dogs and cats
- Brachycephalic Obstructive Airway Syndrome Surgery: Surgical intervention to address the physical abnormalities is the hallmark of BOAS treatment. Surgical options include widening of the nostrils, shortening of the soft palate, and the removal of the laryngeal saccules (if everted). It is important to note that surgery is not considered curative in these breeds. Surgery is instead aimed at reducing the stress on the airways as much as possible and therefore increasing the animal’s quality of life. It is recommended for corrective airway surgery to be performed in brachycephalic animals early on in their lives to reduce the chance of secondary effects of BOAS such as airway collapse and eversion of laryngeal saccules.
- Exercise and temperature management: Aim to exercise and walk animals during the coolest times of the day (e.g. dusk and dawn), be sure not to over exercise your brachycephalic pet and always ensure your pet has access to fresh water.
- Taking care in choosing your pet if buying from a breeder: Be sure to meet your puppy or kitten’s parents as well as the breeder in person to discuss BOAS.
- Visit the vet early for assessment: This involves a physical examination, but your vet may also recommend an airway examination under sedation or anaesthesia and/or radiographs depending on clinical signs. In more severe cases this may also include referral to a veterinary specialist for assessment and advanced imaging.
At Allambie Vet our team is skilled in assessing your pets for brachycephalic obstructive airway syndrome and experienced in performing corrective surgery if necessary. If you have a flat-faced friend in your household, feel free to make an appointment or contact us for advice on an airway assessment or for further information and guidance specific to your pet.