Brachycephalic airway syndrome (BAS), brachycephalic syndrome (BS), and brachycephalic airway obstructive syndrome (BAOS) are synonymous as these describe any anatomical abnormalities in brachycephalic breeds, explained Vet UPENN (University of Pennsylvania School of Veterinary Medicine), a school founded in 1884. These abnormalities lead to the dysfunction of the upper airway.
Brachycephalic dogs suffering from snoring, snorting, and other breathing complications can be severe to the point that some canines need to undergo surgery, said Karen Todd-Jenkins, VMD, of DVM 360, an online news source dedicated to publishing content on veterinary and practice needs. Kevin Benjamino, DVM, DACVS, with MedVet in Columbus, Ohio, noted, “A lot of the time, the owners just don't know. They think, this is what a bulldog is ‘supposed' to be like.” However, brachycephalic dogs are at a disadvantage since their normal airway structures are compressed. Dr. Benjamino added, “The conformational changes create tremendous resistance to air flow.”
What Are the Factors Associated With Major Complications in the Short-Term Post-Operative Period Among Dogs Undergoing BAS Surgery? (2016)
Per the historical data, 87% of dogs had stertor or stridor, 22% had gastrointestinal signs like vomiting or regurgitation,15% had previous BAS surgery, according to Jennifer J. Ree and colleagues of life sciences and biomedical journal portal PMC. Of the eight dogs who had previous BAS surgery, 63% had their previous surgery performed at the study hospital whereas 37% underwent previous surgery by their referring veterinarian. Of the five dogs who underwent previous surgery at the study hospital, four had rhinoplasty, four had caudal staphylectomy, and five had laryngeal sacculectomy.
18% of canines showed no signs of laryngeal collapse (i.e., no everted laryngeal saccules) while 78% showed signs of grade 1 laryngeal collapse. 1 (2%) dog had grade 3 laryngeal collapse. None of the dogs had grade 2 laryngeal collapse whereas laryngeal examination was not documented in 1 dog (2%). Three dogs or 5% required emergency surgery secondary to upper airway obstruction while 95% (52 dogs) had a routine preoperative fast and surgery on a scheduled basis. 89% of dogs had a caudal staphylectomy, 76% had a laryngeal sacculectomy, and 64% had rhinoplasty performed.
38% of canines had other non-BAS surgical procedures, which were performed concurrently. These procedures included castrations or ovariohysterectomies (13%), orthopedic procedures (7%), urethropexies (4%), and excisional biopsies (4%). The canines also underwent each of the following procedures: unilateral left arytenoid lateralization, bilateral enucleation, cystotomy, cholecystectomy, upper gastrointestinal endoscopy, and a cutaneous mast cell tumor excision (all at 2%). Of the 21 dogs with additional surgical procedures, nine had their BAS surgery performed after additional procedures and seven had their surgery performed before the additional procedures. In five dogs, the order of surgeries could not be determined by the researchers. Prior to surgery, radiographs were performed in 47% of dogs and 12% of radiographic evidence of pneumonia. 9% of dogs had their radiographs performed after surgery while 5% had radiographic evidence of pneumonia.
After the surgery, 24% of canines vomited and/or regurgitated. Perioperative medications varied but included anti-inflammatory doses of corticosteroids (75%), metoclopramide constant rate infusion (CRI) (9%), acepromazine (64%), maropitant (13%), trazodone (2%), full opioid agonists (27%), and dexmedetomidine (5%). 41 dogs received perioperative corticosteroids and of these, 61% had them administered pre-surgery or post-surgery. Ree and colleagues highlighted the need for future prospective studies that focus on evaluating management strategies like prokinetic therapy to improve outcomes for canines undergoing BAS surgery.
How Is BOAS Diagnosed?
Routine bloodwork and urinalysis and blood gas analysis are useful in assessing your dog’s overall health. Physical exams are helpful in investigating neoplasia, cardiac disease, and laryngeal paralysis. In some cases, the veterinary team can also utilize radiographs to identify hypoplastic trachea. Medical and surgical options will be considered as soon as a diagnosis is made. If your dog suffers from a moderate or severe case of BOAS, it will most likely need surgery.
What Are the Surgical Options for BOAS?
BOAS lesions at the pharynx are the oversized soft palate and the everted tonsils, said Cambridge Veterinary School: Department of Veterinary Medicine, a teaching and referral hospital. Everted tonsils are usually seen in dogs affected by BOAS, where the tonsils are enlarged, thrusting out from the crypt and narrowing the pharynx. Partial removal of the tonsils increases the space of the pharynges. For dogs with varying degrees of laryngeal collapse as secondary changes and if the primary airway lesions are left untreated, laryngoplasty may be done if your dog has Grade II and III of laryngeal collapse or if it has laryngomalacia or very soft laryngeal cartilages. Laryngeal lateralization (laryngeal “tie-back”) or permanent tracheostomy may be performed if your pet has irreversible Grade III laryngeal collapse.
A veterinary professional can resort to wedge resection of your dog’s nostrils or use Trader’s technique to amputate the nostril wings. These options are effective in widening your pet’s external nostrils. Many dogs with BOAS have second stenosis at the back of the nostril wings, which is known as the nasal vestibule. Alar fold resection can address this issue. Laser-assisted turbinectomy (LATE) can be performed to get rid of intranasal obstruction, especially in French bulldogs and pugs. LATE surgery is suitable for dogs that tend to mouth breathe when resting and dogs that excessively pant during exercise with heat intolerance. Further, the procedure can be for dogs that have sleep-disordered sleeping like apnea and canines that showed little to no improvement after conventional surgery.
What Are the Complications Associated With BOAS Surgery?
Surgery helps improve airflow but it is not possible to correct all the anatomical abnormalities of brachycephalic dogs, stated Willows, an animal hospital. Some of the dogs remain compromised to varying degrees even if the appropriate airway surgery has been done. Additionally, post-operative recovery from anesthetic is a major risk of the procedure. For example, your dog’s airway may become inflamed or swell post-operatively. If necessary, your veterinarian can place a temporary tracheostomy tube. Regurgitation resulting in aspiration pneumonia is another risk. Bear in mind that results of surgery are variable, depending on the severity of BOAS. If your dog has Grade II or III laryngeal collapse, it will have a poorer prognosis.
BOAS cannot be cured, but corrective surgery can help provide your dog with a better quality of life. Regular post-operative appointments are recommended and revision surgery might be required if your dog is severely affected.