Brachycephalic Airway Obstruction Syndrome in Dogs
The brachycephalic airway obstruction syndrome affects dogs with a short nose (brachycephalic means short head). The common brachycephalic dog breeds are English Bulldogs, French Bulldogs, Pekingese, Boston Terriers, Boxer Dogs, Lhasa Apsos, Shih Tzus, Pugs, and Bull Mastiffs.
Anatomic Anomalies
The short bone of the face and the nose and the excessive amount of soft tissue causes a partial obstruction to the normal airflow.
The primary anatomic anomalies are elongated soft palate, stenotic nares (narrow nostril), hypoplastic trachea (narrow windpipe) and redundant pharyngeal tissue (excessive soft tissue on the throat). Patients affected by this syndrome may have one or more of these anatomical changes.
The image shows a lateral view of an elongated soft palate. The black line shows the elongated palate. A normal palate should stop at the black line.
The video shows the elongated soft palate occluding the upper respiratory way.
Treatment
The surgical treatment of the upper respiratory airway, in most cases, also stops secondary problems. Although the surgery significantly improves the quality of life, the patients will still experience stertorous breathing.
Clinical Signs
The anatomic anomalies increase the resistance on the upper respiratory airway resulting in stertorous breathing (noisy breathing), increase respiratory effort, exercise intolerance or collapse especially during hot weather.
A partial occlusion of the upper respiratory airways, with the nose responsible for 80% of the resistance to the airflow, leads to an increase of pressure within the lungs. As a result, the inspiratory muscle contracts for longer during each breath. The increase of the respiratory effort and the increased pressure within the lungs result in secondary pathologies such as non-cardiogenic pulmonary oedema (accumulation of fluid within the lung), the collapse of the larynx (collapse of the throat), hiatal hernia and gastro-oesophageal reflux.
The image shows the excision of the elongated soft palate
Surgical Risk and Complications
The main risk of surgery is the early post-operative period because of throat swelling. Close monitoring of the patient during the post-operative period is required. In very severe cases and when the patient has difficulty breathing because of the swelling, a temporary tracheostomy (hole on a windpipe) may be required to allow better breathing.
Case studies
The image shows stenotic nostrils before surgery. The excessive amount of soft tissue causes occlusion of the nose.
The image shows the widening of the nostrils after a surgical excision.
The image shows an elongated soft palate before surgery. The excessive amount of soft tissue causes occlusion on the normal airflow.
The image shows the palate excision after the surgery.
