Brachycephalic dogs can require special care to keep their breathing normal and healthy

I recently saw an English Bulldog as a patient. Despite the fact that I was treating him for generalized anxiety, the biggest challenge in the exam room was hearing the owner over the dog’s noisy breathing. Loud or difficult breathing is very common in a number of breeds that fall into the “brachycephalic,” or “short-headed,” category, which include the English Bulldog, French Bulldog, Boston Terrier, Cavalier King Charles Spaniel, Lhasa Apso, Shih Tzu, Pug, and Pekinese.

In fact, there is a medical condition named for this phenomenon: Brachycephalic Syndrome. Dogs that suffer from this condition often present to their veterinarians with stertor (a snoring sound while breathing), stridor (a high-pitched sound associated with breathing obstructions), shortness of breath or exercise intolerance, aspiration pneumonia, difficulty sleeping, or open-mouthed breathing. The number and severity of the issues can vary among individuals and over time for the same individual. The average age of onset of breathing problems is 3 years; and these problems often worsen with age.

Diagnosis:

When a brachycephalic dog is presented to the veterinarian for loud or labored breathing, the vet will begin to look for one or more of four physical anomalies that each contribute to the breathing issues and determine its severity. Anomalies include (from tip of nose to back of throat):

  • Stenotic nares. The two nostrils are narrower and droopier than in other dogs; this means that less air can enter the body with each breath.
  • Elongated soft palate. In these dogs, the soft palate can extend inches beyond where it should, allowing it to hang into the back of the mouth and partially block the air from reaching the trachea.
  • Everted laryngeal saccules. These saccules, which sit near the back of the throat, usually exist as pouches that invert into the sides of the mouth; if everted, they are inside-out and project into the airway, further interfering with air passage to the trachea.
  • Hypoplastic trachea. In some brachycephalic dogs, the trachea is narrower than one would expect for a similarly sized dog. This means that, even when the air negotiates the other obstacles, less of it can travel each breath into the lungs to provide oxygen to the body.

Some veterinarians maintain that collapse of the cartilage of the larynx or trachea may also contribute to brachycephalic syndrome; but we will limit our discussion to the four elements listed above.

Although it’s possible to identify the more superficial problems during a routine exam, general anesthesia or deep sedation is often required for a complete exam. X-rays of the chest may help to see tracheal narrowing and aspiration pneumonia.

Aside from the everted saccules, these anomalies are congenital, meaning that the dog is born with them. Most dogs diagnosed with brachycephalic syndrome have more than one of these problems; some unlucky dogs have all four.

Treatment:

Oxygen therapy and anti-inflammatory doses of steroids can provide short-term relief of breathing problems in these dogs. Long-term relief requires surgical intervention. In the case of stenotic nares, the openings of the nostrils can be made larger and any extra tissue removed. Elongated soft palates can be trimmed to a more typical length. Everted saccules can be removed. Sadly, nothing can be done surgically to enhance a narrow trachea.

For some severely affected dogs, these surgical corrections may not provide sufficient relief, and the dog may continue to have difficulty getting enough oxygen. In those cases, the dog may require a permanent tracheostomy, which is a hole in the trachea that is sutured open to provide an unobstructed airway to the lungs. Permanent tracheostomies carry serious risks, including increased threat of foreign-body inhalation and almost-certain drowning if the dog ever decides to submerge itself in water.

Prevention:

Most preventative measures need to happen before adopting a dog:

  • First, determine whether a brachycephalic breed is right for you. However cute you may think your aunt’s French Bulldog is, you need to be prepared to deal with possible breathing problems.
  • Then, find a breeder that carefully chooses sires and dams that are minimally affected; this is a challenge, given the relatively late onset and progressive nature of the problem, paired with a tendency of breeders to mate younger dogs.
  • Once you have adopted the puppy, accustom him to a walking harness, so that no undue pressure is placed on his trachea when he pulls against his leash.
  • Walk your dog during the mildest temperatures of the day and monitor carefully for panting and shortness of breath. The irony is that laryngeal saccule and cartilage problems appear to be exacerbated by harsh breathing, which is the very condition they cause; minimizing exercise when the weather is hot or humid can also minimize breathing difficulties in the first place.
  • Keep your dog lean. Excess weight puts an extra strain on an over-taxed respiratory system.

If, despite precautions, breathing problems do arise, seek veterinary assistance sooner rather than later.

One thing I get asked a lot is whether changing breed standards would correct this problem; my answer is, “I don’t know.” While there is no doubt that breeding for the extreme short noses of the affected breeds is directly responsible for the physical changes that cause brachycephalic syndrome, it’s not clear whether changing breed standards for the these breeds would actually lead to reversal of these problem traits. As far as I can tell, a push toward ethical breeding of only those individuals that appear to be free of problems and neutering of affected individuals is the current plan.

For those owners whose dogs are suffering from this condition, or those wishing to see images of the anomalies and surgical corrections, please see http://www.acvs.org/AnimalOwners/HealthConditions/SmallAnimalTopics/BrachycephalicSyndrome/.

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