Upper respiratory tract disease

Question 1

What does Brachycephalic obstructive syndrome cause?

Answer 1

*Affected breeds have a shortened skull
*Overlong soft palate
*Stenotic nares
*Tracheal / laryngeal hypoplasia
*Pharyngeal collapse, excessive turbinates

Question 2

What are the secondary changes caused by brachycephalic obstructive syndrome?

Answer 2

*Everted laryngeal saccules
*Tonsillar enlargement/protrusion
*Laryngeal collapse
*Tracheal collapse

Question 3

What are the clinical signs of Brachycephalic obstructive syndrome?
(BOS)

Answer 3

*Inspiratory stertor
*Dyspnoea
*Snoring / sleep apnoea
*Exercise intolerance
*Cyanosis
*Fainting / collapse
*Gagging / dysphagia
*Regurgitation
*Cough, pyrexia, dullness with aspiration

Question 4

How is BOS diagnosed?

Answer 4

*Signalment and clinical signs
*Examination of airway
-Tonsils
-Soft palate
-Larynx
*Radiography
-Pharynx / neck
-Thorax

Question 5

How is BOS treated?

Answer 5

*Surgical modification of airway
-Decide whether to perform surgery based on severity of clinical signs
-If required, perform surgery as soon as possible

Question 6

How is emergency stabilisation of BOS performed?

Answer 6

*Cool, quiet environment
*Supplementary oxygen
*Sedation
*Intravenous corticosteroids
*Anaesthetise and intubate if required

Question 7

What are the 3 grades of laryngeal collapse?

Answer 7

Stage 1 - eversion of laryngeal saccules
Stage 2 - eversion of the laryngeal saccules and medial deviation of the cuneiform process of the arytenoids
Stage 3 - eversion of the laryngeal saccules and medial deviation of the cuneiform and corniculate processes of the arytenoid cartilages

Question 8

What is the treatment of laryngeal collapse?

Answer 8

Stage 1 - laryngeal sacculectomy
Stages 2 and 3 - laryngeal sacculectomy
+/- arytenoid caudolateralisation
Permanent tracheostomy

Question 9

What are different causes of laryngeal paralysis?

Answer 9

*Failure of dorsal cricoarytenoid muscle to abduct arytenoid cartilage on inspiration
=Reduced glottis size and increased airway resistance
*Congenital dysfunction of recurrent laryngeal nerve
*Idiopathic dysfunction of recurrent laryngeal nerve
*Metabolic neuropathy
=Hypothyroidism, myasthenia gravis

Question 10

What dog breeds are at risk of getting laryngeal paralysis when older?

Answer 10

Golden retrievers
Labradors
Irish setters
Afghan hounds

Question 11

What are the clinical signs of laryngeal paralysis?

Answer 11

*Inspiratory stridor
*Exercise intolerance
*Fainting / collapse
*Altered phonation
*Cough / gagging during swallowing
*Dysphagia
*Signs are exacerbated by stress, excitement or heat

Question 12

How is laryngeal paralysis diagnosed?

Answer 12

*History and clinical signs
*Laryngoscopy to assess laryngeal function
*Thoracic / cervical radiographs
*Blood tests
*Electromyography / nerve and muscle biopsy
*Edrophonium response test

Question 13

What is the treatment of laryngeal paralysis?

Answer 13

*Left arytenoid lateralisation
-Easier
-Unilateral gives adequate airway
-Bilateral increases risk of postoperative aspiration pneumonia

Question 14

What are the complications of arytenoid lateralisation?

Answer 14

*Aspiration pneumonia
*Failure of tieback
*Seroma
*Development of other signs of neuropathy

Question 15

How would you investigate a tracheal disease?

Answer 15

*Clinical examination
-Auscultation
-Palpation of the cervical trachea
*Diagnostic imaging
-Radiography / computed tomography
-Fluoroscopy
*Tracheobronchoscopy
*Biopsy
*Tracheal wash / BAL

Question 16

What can cause tracheal tears?

Answer 16

*Due to sharp or blunt trauma
*ET tubes in cats
*Asymptomatic or SC emphysema / pneumothorax / pneumomediastinum

Question 17

How would you treat tracheal tears?

Answer 17

*Conservative with cage rest
*Tracheoscopy then surgical repair

Question 18

How is tracheal avulsion diagnosed?

Answer 18

*History
*Tracheoscopy
*Radiographs

Question 19

How is tracheal avulsion treated?

Answer 19

*Debridement + anastomosis
-difficult but good prognosis if successful

Question 20

What are clinical signs of tracheal collapse?

Answer 20

*“Goose honk” cough
*Waxing / waning dyspnoea, exercise intolerance, cyanosis
*Flattening of cervical trachea on palpation

Question 21

How is tracheal collapse diagnosed?

Answer 21

*Signalment, history, clinical signs
*Examination of upper airway
*Fluoroscopy
*Radiography
-Trachea
-Heart
-Lungs
*Tracheoscopy
*Bronchioalveolar lavage

Question 22

What is the treatment of tracheal collapse?

Answer 22

*Medical management often successful
-Corticosteroids
-Antitussives, bronchodilators
-Antibacterials
*Weight loss
*Avoid stress, excitement, vigorous exercise, heat
*Harness
*Treat concurrent disease

Question 23

What is tracheal stenosis how is it caused?

Answer 23

*Abnormal narrowing due to granulation tissue formation after trauma
-Blunt/sharp
-Iatrogenic
-Foreign bodies

Question 24

How do you diagnose tracheal stenosis?

Answer 24

Diagnose on history / signs, imaging,
tracheoscopy

Question 25

How do you treat tracheal stenosis?

Answer 25

*Resection + anastomosis

Question 26

Tracheal neoplasia is v rare - but how would you treat it?

Answer 26

*Resection + anastomosis if localised
*Chemotherapy
*Radiotherapy

Question 27

Why would you perform temporary tracheostomy?

Answer 27

*Bypass potentially life-threatening URT obstruction

Question 28

What are the complications of temporary tracheostomy?

Answer 28

*Tube obstruction (esp. in cats)
*Premature removal
*Gagging / coughing
*Subcutaneous emphysema, pneumomediastinum, pneumothorax
*Infection
*Stenosis

Question 29

Where would you perform a permanent tracheostomy?

Answer 29

*At 4th-6th tracheal rings

Question 30

Why would you perform a tracheal resection?

Answer 30

*Tracheal stricture
*Tracheal stenosis
*Neoplasia
*Granuloma