Brachycephalic Syndrome

Brachycephalic Airway Syndrome

diagram of a dogs throat
Some breeds of dog are susceptible to breathing problems due to the shape of their head, muzzle and throat. The most common breeds affected are the brachycephalic breeds, including the English bulldog, Pug, Pekingese, and Boston terrier. “Brachycephalic Syndrome” refers to the combination of elongated soft palate, stenotic (narrowed) nares, everted laryngeal saccules, and hypoplastic trachea, most of which are commonly seen in these breeds. Elongated soft palate is a condition where the soft palate is too long so that its tip protrudes into the airway and interferes with passage of air.
Stenotic Nares are malformed nostrils that are narrow or collapse inward, causing the dog a problem in breathing through its nose. Everted Laryngeal Saccules is a condition in which tissue within the airway, just in front of the vocal cords, is pulled into the trachea and partially obstructs airflow.

Some dogs with brachycephalic syndrome may also have a hypoplastic (small/narrow) trachea, collapse of the larynx (the cartilages that open and close the upper airway), or paralysis of the laryngeal cartilages.

Signs and Symptoms

Dogs with elongated soft palates generally have a history of noisy breathing, especially upon inspiration (breathing inward), snorting sounds, and wet throat sounds. Some dogs will retch or gag, especially while swallowing. Exercise intolerance, cyanosis, and occasional collapse are common, especially following over-activity, excitation, or excessive heat. The signs associated with stenotic nares and everted laryngeal saccules are similar.

Treatment Options

image of soft palate surgery
Soft palate abnormalities should be treated if they cause distress to the dog, become more severe with time, or cause life-threatening obstruction. This means resection of the excess soft palate may be necessary. Soft palate resection is performed using a scalpel blade, scissors, Ligasure device or CO2 laser. The palate is stretched (Figure 5) and the excess tissue is removed. Most dogs improve with surgery but still have some intermittent noise or snoring. The CO2 laser may reduce bleeding, but offers no additional significant advantage. If the laryngeal saccules are everted, they may be removed at the same time as the soft palate procedure. Correction of stenotic nares helps improve breathing and is done at the same time.

Possible Complications of Surgery

Patients must be monitored very closely immediately after surgery. Inflammation and swelling can obstruct the airway, making breathing very difficult. Patients are typically observed in the hospital for at least 24 hours. Post-operative coughing and gagging are common. In chronic cases in which the laryngeal cartilages have become inflexible, removal of the elongated soft palate and laryngeal saccules may not provide enough relief. The creation of a new permanent opening into the trachea in the neck area (called a permanent tracheostomy) may be the only solution, although there are complications associated with this procedure as well.

Prognosis

The prognosis is good for young animals. They generally will breathe with increased ease and with significantly reduced respiratory distress. Activity level can markedly improve. Older animals may have a less favorable prognosis, especially if the process of laryngeal collapse is present.