BRACHYCEPHALIC OBSTRUCTIVE AIRWAY SYNDROME
Brachycephalic Obstructive Airway Syndrome commonly occurs in dog breeds which have a short nose. Bulldogs and Pugs, are the most commonly affected breeds, however other breeds such as, Staffordshire Terriers, Mastiffs, Cavalier King Charles Spaniels, Boxers, may also suffer from upper airway obstruction.
Brachycephalic Syndrome refers to obstruction of the air passage at the back of the throat and nose, due to a combination of overly long soft palate, very narrow nasal passages (nares), and inflammation of other structures in the back of the throat which cause further narrowing of the upper airways. The long soft palate prevents the normal passage of air to the wind pipe (trachea), causing increased effort to breath and inflammation of the throat. Patients ususally present with difficulty breathing, noisy breathing, snoring, and in severe cases will turn blue (cyanosis) and collapse. Patients will deteriorate during periods of hot and humid weather (spring and summer) and during exercise, when the demand on breathing is highest. Signs will get worse with age, as the cartilages at the back of the throat (larynx) and wind pipe deteriorate. Inflammation causes further swelling of the soft tissues (laryngeal saccules, tonsils, mucosa), all of which combine to make the breathing worse. If treated the breathing is markedly improved and the risk of fatal respiratory problems is markedly decreased.
The benefits of surgery performed early out-weigh the risks. The main complication associated with surgery is in the immediate post-surgery period, where there may be significant swelling and obstruction of the airway. Should this occur, a temporary hole in the base of the neck (tracheostomy) may be required until the swelling subsides and the patient is able to breath without by-passing the mouth and larynx.
Occasionally the sutures used to shorten the soft palate may require removal if they cause irritation, which involves a brief sedation.
Brachycephalic patients are also at risk of chronic gastric reflux and heart-burn (oesophagitis) due to the breathing issues. This may cause long-term regurgitation and require medication to limit the symptoms.
Surgery involves shortening the soft palate (palatoplasty), opening the nasal passages (rhinoplasty), and occasionally removing the tonsils and laryngeal saccules.
The prognosis following surgery is good, with an improvement in the airway passage and reduced risk of severe breathing diffculty. Some noise whilst breathing and sonring may persist, but should be better than pre-surgery. The prognosis for patients with longer term breathing difficulty is not as good due to degeneration of the cartilages at the back of the throat (larynx) and wind-pipe (trachea). In pateints where the cartilages of the larynx or trachea have collapsed, a laryngeal tie-back surgery or tracheal stent may be required.