Brachycephalic dog breeds have increased in popularity over the last 15 years while suffering from multiple well-documented health problems. Despite increased general awareness of their conformation-related problems, their appeal continues to grow. The result is increasing numbers of dogs selectively bred for shorter noses, wider faces, and predisposition to brachycephalic obstructive airway syndrome (BOAS).1
Understanding the pathogenesis of BOAS has increased, along with appreciation for the multiple morbidities that accompany genetic selection for brachycephaly. It was rare to find research or publications about BOAS and the implications for patient welfare before 2005. Since then, more than 110 scientific publications have published advanced knowledge about how to best manage patients affected by BOAS and influence selection in affected breeds.2
These developments have been accompanied by increased use of CO2 surgical lasers in small animal practices. Practitioners have become adept at using surgical lasers to facilitate correction of obstructive airway abnormalities. This has increased the frequency of surgical intervention for BOAS patients at earlier ages. Early correction of airway obstruction is now more common and helps predisposed patients avoid the complications of BOAS.3 Although this paradigm shift has improved the quality of life of many brachycephalic dogs, the overall welfare of brachycephalic breeds remains challenging.
What we have learned
Brachycephalic conformation includes multiple anatomical abnormalities. Stenotic nares, aberrant turbinates, elongation of the soft palate, and tracheal hypoplasia are the physical abnormalities restricted airflow. Greater pressures are required during breathing, particularly during inspiration. Over time, increased negative pressure in the airways results in secondary changes, including pharyngeal hyperplasia, eversion of the laryngeal saccules, hyperplasia of the tonsils, and laryngeal and bronchial collapse.
