BOAS Flashcards
What are the 8 components of BOAS
1) Elongated soft palate
2) Redundant pharyngeal folds
3) Stenotic nares
4) Macroglossia
5) Aberrant Nasal turbinates
6) Hypoplastic trachea
7) Everted Saccules
8) Laryngeal collapse
What causes secondary changes which further narrow the upper airway
1) Negative pressure (stenotic nares, etc.) from secondary factors everted laryngeal saccules, everted tonsils, laryngeal collapse
2) Edema, erythema, swelling
3) Further narrow the upper airway
What noises might you hear from BOAS patients
1) Nasal snorting (stertor) from nasal or elongated soft palate
2) Stridor can also occur
in BOAS, what causes further narrowing of the upper airway?
edema, erythema, swelling from negative pressure from secondary components (everted laryngeal saccules, everted tonsils, laryngeal collapse)
What secondary components cause edema, erythema, swelling from negative pressure
laryngeal saccules, everted tonsils, laryngeal collapse
What are the GI disease components of BOAS
1) Regurgitation
2) Sliding Hiatal Hernias
3) Gastritis
4) Inflammatory GI disease - reversible with treatment
BOAS dogs have what other diseases
37% esophagitis
89% gastritis
Hiatal hernia (up to 40%), french bulldogs
nostrils of the dog are called
nasal aperature
alar fold typically collapses
medially (dynamic component)
What is Poiseuille’s Law?
Flow is proportional to radius ^4,
How do you know if a soft palate is elongated
Laryngeal exam (light plane of anesthesia, ventral recumbency, tongue in neutral position)
Hold the tongue and lift the soft palate with an instrument
it will be too long if the soft palate extends beyond the tip of epiglottis
if intubated use palatine tonsils (divide length into thirds) - cut to middle and caudal 1/3 of tonsil
How do you know the long palate is elongated if the patient in intubated
if intubated use palatine tonsils (divide length into thirds) - cut to middle and caudal 1/3 of palantine tonsil
What could happen if the soft palate is cut too short
rhinitis and increased risk of aspiration pneumonia
What are everted saccules
the everted mucosa of the laryngeal ventricle
negative pressure is generated during inspiration
_____% of english bulldogs have hypoplastic tracheas
53.9%
What are aberrant nasal turbinates
nasopharyngeal turbinates: 21% of brachycephalic breeds
-Hypertrophy
-Occlusion of nasopharynx as they extend caudally there
-80% of pugs (originally reported) but many have them
What can you do for aberrant nasal turbinates
Laser ablation
-96% of french bulldogs and 65% of pugs show regrowth at 6months
What are you concerned about when you hear high pitched noises in a breathing BOAS dog
laryngeal collapse
What is laryngeal collapse
loss of cartilage structure that becomes weak and soft
causes inspiratory stridor - high pitched, wheezing sound
What sounds do you hear with laryngeal collapse
inspiratory stridor
-high pitched
-wheezing sound
What are the 3 stages of laryngeal collapse
1) Laryngeal saccule eversion
2) Cuneiform cartilage adduction
3) Corniculate cartilage adduction
How do you treat laryngeal collapse
Prevention is best, treat the treatable conditions because not the best treatments
+/- laryngeal tie back
permanent tracheostomy * is the best treatment
T/F: laryngeal tie back is a good method for treating laryngeal collapse
False- doesnt look good
What is the best treatment for laryngeal collapse
permanent tracheostomy (hard sell)
How do you treat stenotic nares
1) Vertical Wedge Resection
2) Punch Biopsy
3) Nares amputation
4) Alapexy
How do you treat elongated soft palate
1) Staphylectomy - shortening soft palate
2) Folded Flap palatoplasty - for long and thic
shortening of the soft palate
Staphylectomy
T/F: sacculectomy for everted saccules is controversial
True
How do BOAS dogs typically present
Snoring, stertor
High pitched wheeze, stridor
restlenessness at night/apnea
exercise and or heat intolerance
dyspnea
syncope
Gi signs: vomiting and regurgitation
For BOAS dogs, how do you treat in emergency
Cool environment
oxygen therapy
sedation
dexamethasone (0.25mg.kg IV) for inflammation
Why are thoracic rads important for BOAS workup
what 4 things are you looking for?
Pneumonia (aspiration) - treat before sedating
Hiatal hernia
Tracheal size
Pulmonary edema
What should you do when inducing BOAS dogs with anesthesia
-No stress
-Hyperoxygenation: mask
-Quick induction
-Quick atraumatic intibation (small tube)
-Electrocardiogram (vagal tone from GI disease )
Why are sacculectomy for everted laryngeal saccules controversial
Sacculectomy - had more complications
more had non-treated group. moderate (>48 hours, mild cough, dyspnea) and severe (dyspnea, regurgitation requring tx, temp trach, tx for pneumonia, ventilator, euthanasia, death) complications
T/F: avoid cautery when doing staphyloectomy
True
Where do you cut the soft palate
just at the border of the middle 1/3 and caudal 1/3 of the palatine tonsil
How do you suture a staphylectomy
Simple continuous- apposing oral and nasal mucosa
good apposition to prevent scar tissue
Alternative surgical techniques for elongated soft palate
1) CO2 laser- cuts and seals tissue, oxygen
2) Bipolar vessel sealant device
3) Folded Flap Palatoplasty- treats long and thick palates
Folded Flap Palatoplasty- treats
long and thick palates
Methods for stenotic nares tx
1) Vertical Wedge Resection
2) Horizontal Wedge Resection
3) Trader’s
4) Punch Biopsy
5) Alapaexy
How do you recover dogs from BOAS sx
-Delayed extubation
-Calm environment
-Prepared with: sedation / reversal agent, induction agent, small ET tubes and laryngoscope, suction, supplemental oxygen
Dex SP 0.25mg/kg IV during surgery
What are some common complications of BOAS sx
-Regurgitation/vomiting
-Nasal discharge
-aspiration pneumonia
-palate too short: rhinitis, aspiration pneumonia
-suture failure of nose and collapse
-need for temporary tracheostomy (3-5%)
-Severe dyspnea and death (3-5%)
What should you give BOAS dogs if you notice post-op GI signs
Omeprazole 0.7 mg/kg POq24h
Cisapride 0.2-0.5mg/kg PO TID
What percent of dogs have significant improvement and good to excellent outcome
94%
What should you do for aftercare for BOAS sx
-Discharge later in the afternoon or following day
-Analgesia
-Soft food for 7 days
–Ecollar for nares
-Recheck exam in 2 weeks
+/- short course of steroids of Nsaids
-if GI signs post-op Omeprazole or Cisapride
-Harness
-Weight management
