BOAS CBL

Rex is an 8-month-old French Bulldog with noisy breathing and exercise intolerance. Most likely syndrome?

Brachycephalic obstructive airway syndrome (BOAS).

What does stridor sound like and where does it usually originate?

High-pitched upper-airway sound, particularly associated with laryngeal narrowing.

What does stertor sound like and where does it originate?

Low-pitched snoring/snorting sound from the nasal/nasopharyngeal upper airway.

Rex has mild stridor and prominent stertor. What does that localization suggest?

Obstruction at more than one upper-airway level, including nasal/pharyngeal and potentially laryngeal regions.

Why is severe stridor more concerning than uncomplicated stertor?

It may reflect narrowing near the laryngeal airway and impending serious airflow limitation.

What breathing phase is especially difficult in Rex?

Inspiration, consistent with upper-airway obstruction.

What suspected tracheal abnormality requires imaging confirmation?

Hypoplastic trachea; palpation is suggestive, radiographs help confirm.

What is the BOAS thermal vicious cycle?

Heat/panting → turbulence and swelling → greater narrowing → more work/panic and heat → worsening obstruction.

Which sedative combinations are discussed for oral examination in the lecture?

Low-dose acepromazine plus butorphanol; or carefully monitored low-dose dexmedetomidine.

What important risks accompany dexmedetomidine in a BOAS patient?

Bradycardia and respiratory depression; careful monitoring is necessary.

Which BOAS component is described as most common in the lecture?

Elongated soft palate.

Where should the normal soft palate end according to the slides?

Approximately mid-tonsil to caudal tonsil level, near the epiglottic tip.

How does an elongated soft palate impede breathing?

It encroaches on the pharyngeal airway, increasing turbulent airflow and inspiratory obstruction.

Why do laryngeal saccules evert in BOAS?

Chronic increased inspiratory effort creates negative pressure that draws the saccules into the airway.

What do everted laryngeal saccules indicate clinically?

Secondary obstructive change resulting from ongoing upper-airway negative pressure.

What nonrespiratory syndrome can accompany BOAS in brachycephalics?

Brachycephalic ocular syndrome, including eye exposure and corneal injury risk.

What other upper-airway disorders appear in the lecture differential?

Laryngeal collapse, rhinitis, and laryngeal paralysis (GOLPP).

What GI/respiratory comorbidities are associated with BOAS?

Gastroesophageal reflux, sliding hiatal hernia, and aspiration pneumonia.

What two diagnostics are highlighted first in Rex’s work-up?

Thoracic radiographs and a thorough upper-airway examination.

Which extra imaging and endoscopic studies may help characterize BOAS?

CT of head/neck/thorax and rhinoscopy or pharyngeal, laryngeal, and tracheal endoscopy.

What functional evaluations are mentioned for BOAS?

Respiratory Function Grading Scheme and pulse oximetry before/after exercise.

Why is medical management of BOAS palliative rather than curative?

It reduces turbulence, inflammation, and edema but does not correct the anatomical deformities.

What immediate non-surgical environmental measures reduce BOAS stress?

Strict rest, a cool environment, and avoidance of hot or humid conditions.

After sedation, nostril airflow stops and effort rises. What immediate maneuver is suggested?

Open the mouth to permit airflow while preparing to secure the airway.

What should be evaluated before passing the endotracheal tube?

The laryngeal apparatus and laryngeal function.

What surgical procedure addresses stenotic nares?

Rhinoplasty/ala-vestibuloplasty to improve nasal airflow.

Why can ala-vestibuloplasty improve airflow beyond simple nostril widening?

It removes obstructive internal alar fold and nasal vestibular tissue.

What procedure shortens an elongated soft palate?

Staphylectomy, using scissors/sutures, cautery, or CO₂ laser.

What surgery can relieve obstruction from everted laryngeal saccules?

Careful excision of the everted saccules.

Can surgery correct a hypoplastic trachea?

No

When is a temporary tracheostomy more likely to be considered?

Severe clinical signs such as cyanosis or syncope with multiple obstructive defects.

Is presurgical tracheostomy needed in most BOAS patients?

No; it may aid exposure but is not routinely necessary.

What is the highest-risk period emphasized after BOAS anesthesia?

Recovery

What postoperative complications require active monitoring?

Difficulty breathing, coughing, regurgitation, and bleeding.

How does younger age affect expected BOAS surgical improvement?

The lecture reports about 90% improvement under 2 years versus 70% over 2 years.

Which anatomical progression predicts less favorable BOAS prognosis?

Laryngeal collapse.

Does corrective surgery permanently cure BOAS?

No; it can substantially improve airflow and quality of life, but residual disease may remain.

What owner-reported signs require immediate emergency assessment?

Cyanosis, collapse, or severe stridor/respiratory difficulty.

A dog still snores after corrective surgery. What is the best owner message?

Improvement does not ensure complete anatomical correction; reassess symptoms and maintain lifelong precautions.

Rex has new cough, fever, and increased breathing effort after regurgitation. Concern?

Aspiration pneumonia as a BOAS-associated complication; prompt evaluation is warranted.