Brachycephalic syndrome is a pathological condition affecting short nosed dogs and cats which can lead to severe respiratory distress. There are four different anatomical abnormalities that contribute to the disease, all of which occur more commonly in brachycephalic breeds:- an elongated soft palate, stenotic nares, a hypoplastic trachea, and everted laryngeal saccules. Because all of these components make it more difficult to breathe, in situations of exercise, stress, or heat, an animal with these abnormalities may be unable to take deep or fast enough breaths to blow offcarbon dioxide. This leads to distress and further increases respiratory rate and heart rate, creating a vicious cycle that can quickly lead to a life-threatening situation. Brachycephalic dogs are more likely to die during air travel and have been banned by many airlines. Dogs experiencing a crisis situation due to brachycephalic syndrome typically benefit from oxygen, cool temperatures, sedatives, and in some cases more advanced medical intervention, including intubation.
Symptoms progress with age and typically become severe by 12 months. Despite observing clinical signs of airway obstructions, some owners of brachycephalic breeds may perceive them as normal for the breed, and may not seek veterinary intervention until a particularly severe attack happens. After awaking from surgery, most dogs that are intubated will try to claw out their tracheal tube. In contrast, brachycephalic dogs often seem quite happy to leave it in place as it opens the airway, making it easier to breathe.
Secondary conditions
Other conditions may be observed concurrently. These include swollen/everted laryngeal saccules, which further reduce the airway, collapsed larynx, and chronic obstructive pulmonary disease caused by the increased lung workload. Brachycephalic syndrome has been linked to changes in the lungs, as well as the gastrointestinal tract including bronchial collapse, gastroesophageal reflux, and chronic gastritis.
Diagnosis
This syndrome is diagnosed on the basis of the dog's breed, clinical signs, and results of a physical examination by a veterinarian. Stenotic nares can usually be diagnosed on visual inspection. Diagnosis of an elongated soft palate, everted laryngeal saccules, or other associated anatomical changes in the mouth will require heavy sedation or full general anesthesia.
Treatment
Treatment consists of surgery for widening the nostrils, removing the excess tissue of an elongated soft palate, or removing everted laryngeal saccules. Early treatment prevents secondary conditions from developing. Potential complications include hemorrhages, pain, and inflammation during and after surgery. Some veterinarians are hesitant to perform soft palate correction surgery. With CO2 surgical lasers, these complications are greatly diminished.
Prevention
To prevent or limit exacerbation of symptoms, avoid stress and high heated climates. Maintain ideal body weight and avoid overfeeding. Use harnesses instead of collars to avoid pressure on the trachea. The risk of brachycephalic syndrome increases as the muzzle becomes shorter. To avoid producing affected dogs, breeders may choose to breed for more moderate features rather than for extremely short or flat faces. Dogs with breathing difficulties, or at least those serious enough to require surgery, should not be used for breeding. Removing all affected animals from the breeding pool may cause some breeds to be unsustainable and outcrossing to non-brachycephalic breeds might be necessary.
