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New Baltimore Animal Hospital

Brachycephalic Airway Syndrome (BAS)

Brachycephalic Airway Syndrome (BAS)

BAS is a group of structural deformities commonly seen in brachycephalic (short-snouted) dogs and cats, such as Bulldogs, Pugs, Pekingese, Himalayans, and Persians.

These pets have a genetic developmental defect in the bones of the base of the skull (head) that causes normal width but abnormally short length. The softer tissues of the head are normal length and do not fit.

Problems include: Stenotic nares, elongated soft palate and everted laryngeal saccules. Some breeds also have tracheal hypoplasia.

Clinical signs of BAS are due to upper airway obstruction and included noisy/loud breathing, labored breathing, gagging or retching, snoring, exercise intolerance, and in severe cases, collapse and death. Excitement, stress, heat and very high or low humidity can make these worse. Surgical correction of the stenotic nares and elongated soft palate in a young animal can dramatically improve their lives and prevent most of the long-term complications. Correction is usually scheduled at the time of spay/neuter or 5-6 months of age.

Stenotic nares: Narrowed nostril diameter which limits air flow and makes them work harder to breathe in. This is corrected surgically using the Ellman Radiosurgery unit, which minimizes post-op pain, swelling, and scarring.

Elongated Soft Palate: In brachycephalic animals, the soft palate is much too long and extends into the back of the throat, or occasionally down into the trachea. As the animal breathes in, the flap of tissue gets sucked in and can temporarily block the airway. Over time, the suction stretches the extra tissue even more and it swells and thickens, causing more blockages. Treatment is: Shortening with radiosurgery.

Everted Laryngeal Saccules: These are soft out-pouchings of the larynx (beginning of the windpipe). In untreated dogs, they can flip inside-out and protrude into the larynx further blocking the airway. This is commonly an emergency surgery to treat.

The longer a pet lives with these conditions, the more likely an emergency blockage will happen.