Brachycephalic Airway Syndrome

Question 1

What are the 4 components of congenital BAS?

Answer 1

1. stenotic nares
2. aberrant turbinates
3. soft palate elongation and hyperplasia
4. tracheal hypoplasia

Question 2

what are the 4 secondary components of BAS?

Answer 2

1. everted laryngeal saccules
2. laryngeal collapse
3. mucosal edema (d/t constant airway inflammation)
4. gastroesophageal reflux (potential aspiration)

Question 3

what are 3 breeds commonly affected with BAS?

Answer 3

1. bull dogs (english and french)
2. pugs
3. bosten terriers

Question 4

what is the classic history of a dog that has BAS?

Answer 4

snoring or inspiratory stertor
dyspnea
possibly syncope
heat, stress, exercise intolerance
+/- GI signs (vomiting, regurg)

Question 5

What GI signs can dogs with BAS have?

Answer 5

1. vomiting
2. regurgitation

Question 6

what effect does having a shorter skull have on developing BAS?

Answer 6

compresses the nasal passages
alters the pharyngeal anatomy
and leads to increased inspiratory resistance (negative pressure)

Question 7

what specific anatomical features do pugs have that cause BAS?

Answer 7

1. dorsal rotation of the maxillary bone
2. severely underdeveloped/absent frontal sinuses
3. ventral orientation of olfactorial bulb

Question 8

what are the primary and secondary pathophysiologic causes of BAS?

Answer 8

primarily – anatomical changes lead to increased respiratory resistance (negative pressure)

secondary conditions (everted laryngeal saccule, laryngeal collapse, mucosal edema, gastroesophageal reflux) result from the primary condition and they contribute to the clinical signs that appear.

Question 9

how do you diagnose BAS?

Answer 9

1. history of snoring, insp. dyspnea, stridor, abdominal effort, and syncope
2. PE
3. imaging – thoracic xray, head and cervical CT, endoscopy of upper airway (r/o other possible causes of respiratory difficulty)

Question 10

how do we medically manage BAS?

Answer 10

1. if in acute respiratory distress, then: active cooling, sedatives, supplemental oxygen, antiinflammatories (steroids), IV cath
2. for GI signs: gastric acid reduction (H2 blockers, PPIs – famotidine, omeprazole, etc.) and prokinetics (metoclopromide, cisapride)

Question 11

what surgical therapy is available for dogs with BAS?

Answer 11

Primary procedures:
1. Alaplasty (fixes stenotic nares)
2. staphylectomy (fixes elongated SP)
3. folded flap palatoplasty (thins and corrects elongated SP)

Secondary procedures:
1. sacculectomy (resection of laryngeal saccules)
2. turbinectomy (resect malformed obstructive conchae in ventral and medial nasal turbinates to decrease intranasal airway resistance)

Question 12

How do you perform an alaplasty?

Answer 12

1. make a wedge incision on the nares using a 15 or 11 blade or biopsy punch
2. apply direct pressure for hemostasis, NO cautery
3. use absorbable monofilament suture (monocryl/poliglecaprone25) with a simple interrupted pattern to align/appose the cut edge to the side (make sure each side if symmetrical)

Question 13

How do stenotic nares lead to BAS?

Answer 13

the axial deviation of of the dorsolateral nasal cartilage causes significant negative pressures in the larynx and lower airways. The pressures lead to supraphysiologic stress, edema, and eventual secondary laryngeal collapse.

Question 14

How does elongated/hyerplastic soft palate cause BAS?

Answer 14

normally the epiglottis is OVER the SP

with elongation and hyperplasia, the SP extends BEYOND the epiglottis (>1-3 mm), therefore the epiglottis is BELOW the SP.
this causes airway obstruction.

Question 15

What are the options to surgically treat elongated/hyperplastic soft palate?

Answer 15

1. staphylectomy
2. folded flap palatoplasty (thins SP and corrects length)

Question 16

what are the landmarks for staphylectomy?

Answer 16

tip of epiglottis
middle to caudal palatine tonsils/crypt

Question 17

what are the beneficial purposes of lasers and sealing devices?

Can you think of some downsides to these techniques?

Answer 17

1. decreases hemorrhage
2. decreases swelling (bc procedure is quicker)

but can delay healing and cause collateral tissue damage, but maybe its not clinically significant.
Do not let the laser/ligasure tip touch any portion of the tissue that is staying because you will cause thermal burns

Question 18

how do you surgically treat everted laryngeal saccules?

Answer 18

1. apply dorsomedial traction
2. transect base with scissors or perform traction amputation
3. apply direct pressure for hemostasis

Question 19

How do you surgically treat aberrant turbinates?

Answer 19

turbinectomy – resect malformed obstructive conchae in ventral and medial nasal turbinates.
this decreases intranasal airway resistance

Question 20

What is critical for surgical recovery?

Answer 20

• adequate airflow (some may need ventilator)
• slow anesthetic recovery with O2
• maintain the ET tube, reintubate if necessary and be prepared for tracheostomy
• corticosteroids (reduce inflammation)
• withhold food and water (overnight)
• IV fluids

Question 21

T/F: diagnosis of BAS may occur late but surgical correction is recommended as soon as possible to minimize secondary conditions

Answer 21

true

educate owners early on that the noises they make and other symptoms assoc with BAS are NOT normal. Enlarging the airway earlier on will reduce secondary changes like everted saccules or laryngeal collapse that can occur over their lifetime.

Question 22

What are the 3 stages of laryngeal collapse?

Answer 22

stage I - laryngeal saccule eversion (mild)
stage II - medial displacement of cuneiform process
stage III - collapse of corniculate process

Question 23

what is the treatment for laryngeal collapse?

Answer 23

• treat the primary disease**
• if needed, do arytenoid lateralization
• permanent tracheostomy

Question 24

what is the prognosis for dogs with BAS?

Answer 24

~90% improve with surgery

perioperative mortality <4%
but long term recurrence of clin signs can be 100%.

Question 25

what do thoracic radiographs help rule out in cases of BAS?

Answer 25

1. cardiac disease
2. aspiration pneumonia (remember if your xrays do not show evidence of AP but clinical signs support it, there is a lag time)
3. sliding hiatal hernia

Question 26

what is the best timing for surgical correction of BAS?

Answer 26

EARLY – after 6 months of age. do medical management until 6 months so they can grow, then do surgery.

Question 27

how much tissue should you resect when surgically correcting an elongated SP with a staphylectomy?

Answer 27

Dont want to take TOO much tissue because then will be at risk for aspiration.

Aim to resect the SP to the middle-caudal level of the palatine tonsils / crypts

Question 28

For a staphylectomy, what suture and suture pattern do you use?

Answer 28

simple continuous
monocryl (poliglecaprone 25)
you must have mucosa to mucosa apposition, if not the healing will not be as optimal

you can also use ligasure

Question 29

which surgical procedure THINS and corrects EXCESSIVE LENGTH of the soft palate?

Answer 29

folded flap palatoplasty

technically challenging procedure!

Question 30

how do you perform a sacculectomy to correct everted laryngeal saccules?

Answer 30

dorsomedial retration of the laryngeal saccules, then transect them at their base with scissors.

OR

traction amputation

then place pressure for hemostasis, no suture

Question 31

does performing secondary procedures like sacculectomy and turbinectomy help dogs with BAS?

Answer 31

Not sure. Subjective and needs more data.