Some dogs and cats have short faces and pushed in or shortened noses. The skull has been genetically altered. Although these dogs and cats are considered to be cute, the changes in their faces can be very detrimental to their breathing.
The dog breeds affected include: Old English Bulldogs, Pugs, Pekingese, Shih Tzus, Lhasa Apsos, Boxers, Boston Terriers, French Bulldogs, Bull Mastiffs, and Shar Peis. The cat breed primarily affected is the Persian.
Dogs with brachycephalic syndrome will have all or some of the following abnormalities:
1) Stenotic nares- nostrils that are too small making it hard to breathe through the nose
2) An elongated soft palate which can block the larynx
3) A hypoplastic or very small trachea
4) Everted laryngeal saccules- swollen tissue by the vocal cords
Persian cats only suffer from the stenotic nares (nostrils) and this can be corrected surgically.
All of these abnormalities impede the airflow into the respiratory system and cause increased airway resistance. This can cause breathing to become labored and making it difficult to breathe in. This noisy breathing is called stridor. The difficulty breathing can worsen as a dog ages. The more abnormalities the dog has, the more severe the symptoms. It can develop other problems over time, including bronchitis, pneumonia, and a collapsing trachea. The lung tissue becomes irritated and inflamed. The heart can become strained. A dog suffering from brachycephalic syndrome is sensitive to heat and excitement. As the dog pants to stay cool, the tissue in the respiratory system can swell and make breathing even harder. Obesity can add to these problems.
If chronic bronchitis occurs, it can be treated with steroids, antibiotics, and weight loss.
The best treatment for brachycephalic syndrome is to surgically correct some or all of the abnormalities when the dog is young or under age 2 years. The stenotic nares can be corrected easily at the time of neuter or spay. If the soft palate is very long, it can be corrected by a surgical specialist. If one or two of these problems are corrected early, the dog may not develop the everted saccules.
A small, hypoplastic trachea cannot be corrected surgically.
The stenotic nares can be easily diagnosed with a physical exam. The other abnormalities would require anesthesia to observe if there is an elongated soft palate, everted saccules, or a hypoplastic trachea.
Over time, if the breathing problems worsen, a very serious condition can develop called laryngeal collapse. The cartilage folds of the larynx become very weak and fall into the laryngeal opening blocking the airflow. This is a very grave condition and may require a permanent tracheostomy. This condition can prove fatal.
Below are pictures showing a dog before and after undergoing a surgical technique to open up the stenotic nares. This technique shows a bit of tissue on the side of the nostril, called the alar fold, which is simply removed. Another technique involves removing a wedge of tissue and suturing the edges to make the nostril larger. This surgery greatly improves a dog's ability to breathe. This can easily be done at the time of a spaying or neutering.