Upper respiratory tract disease Flashcards
What does Brachycephalic obstructive syndrome cause?
*Affected breeds have a shortened skull
*Overlong soft palate
*Stenotic nares
*Tracheal / laryngeal hypoplasia
*Pharyngeal collapse, excessive turbinates
What are the secondary changes caused by brachycephalic obstructive syndrome?
*Everted laryngeal saccules
*Tonsillar enlargement/protrusion
*Laryngeal collapse
*Tracheal collapse
What are the clinical signs of Brachycephalic obstructive syndrome?
(BOS)
*Inspiratory stertor
*Dyspnoea
*Snoring / sleep apnoea
*Exercise intolerance
*Cyanosis
*Fainting / collapse
*Gagging / dysphagia
*Regurgitation
*Cough, pyrexia, dullness with aspiration
How is BOS diagnosed?
*Signalment and clinical signs
*Examination of airway
-Tonsils
-Soft palate
-Larynx
*Radiography
-Pharynx / neck
-Thorax
How is BOS treated?
*Surgical modification of airway
-Decide whether to perform surgery based on severity of clinical signs
-If required, perform surgery as soon as possible
How is emergency stabilisation of BOS performed?
*Cool, quiet environment
*Supplementary oxygen
*Sedation
*Intravenous corticosteroids
*Anaesthetise and intubate if required
What are the 3 grades of laryngeal collapse?
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
What is the treatment of laryngeal collapse?
Stage 1 - laryngeal sacculectomy
Stages 2 and 3 - laryngeal sacculectomy
+/- arytenoid caudolateralisation
Permanent tracheostomy
What are different causes of laryngeal paralysis?
*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
What dog breeds are at risk of getting laryngeal paralysis when older?
Golden retrievers
Labradors
Irish setters
Afghan hounds
What are the clinical signs of laryngeal paralysis?
*Inspiratory stridor
*Exercise intolerance
*Fainting / collapse
*Altered phonation
*Cough / gagging during swallowing
*Dysphagia
*Signs are exacerbated by stress, excitement or heat
How is laryngeal paralysis diagnosed?
*History and clinical signs
*Laryngoscopy to assess laryngeal function
*Thoracic / cervical radiographs
*Blood tests
*Electromyography / nerve and muscle biopsy
*Edrophonium response test
What is the treatment of laryngeal paralysis?
*Left arytenoid lateralisation
-Easier
-Unilateral gives adequate airway
-Bilateral increases risk of postoperative aspiration pneumonia
What are the complications of arytenoid lateralisation?
*Aspiration pneumonia
*Failure of tieback
*Seroma
*Development of other signs of neuropathy
How would you investigate a tracheal disease?
*Clinical examination
-Auscultation
-Palpation of the cervical trachea
*Diagnostic imaging
-Radiography / computed tomography
-Fluoroscopy
*Tracheobronchoscopy
*Biopsy
*Tracheal wash / BAL
What can cause tracheal tears?
*Due to sharp or blunt trauma
*ET tubes in cats
*Asymptomatic or SC emphysema / pneumothorax / pneumomediastinum
How would you treat tracheal tears?
*Conservative with cage rest
*Tracheoscopy then surgical repair
How is tracheal avulsion diagnosed?
*History
*Tracheoscopy
*Radiographs
How is tracheal avulsion treated?
*Debridement + anastomosis
-difficult but good prognosis if successful
What are clinical signs of tracheal collapse?
*“Goose honk” cough
*Waxing / waning dyspnoea, exercise intolerance, cyanosis
*Flattening of cervical trachea on palpation
How is tracheal collapse diagnosed?
*Signalment, history, clinical signs
*Examination of upper airway
*Fluoroscopy
*Radiography
-Trachea
-Heart
-Lungs
*Tracheoscopy
*Bronchioalveolar lavage
What is the treatment of tracheal collapse?
*Medical management often successful
-Corticosteroids
-Antitussives, bronchodilators
-Antibacterials
*Weight loss
*Avoid stress, excitement, vigorous exercise, heat
*Harness
*Treat concurrent disease
What is tracheal stenosis how is it caused?
*Abnormal narrowing due to granulation tissue formation after trauma
-Blunt/sharp
-Iatrogenic
-Foreign bodies
How do you diagnose tracheal stenosis?
Diagnose on history / signs, imaging,
tracheoscopy
How do you treat tracheal stenosis?
*Resection + anastomosis
Tracheal neoplasia is v rare - but how would you treat it?
*Resection + anastomosis if localised
*Chemotherapy
*Radiotherapy
Why would you perform temporary tracheostomy?
*Bypass potentially life-threatening URT obstruction
What are the complications of temporary tracheostomy?
*Tube obstruction (esp. in cats)
*Premature removal
*Gagging / coughing
*Subcutaneous emphysema, pneumomediastinum, pneumothorax
*Infection
*Stenosis
Where would you perform a permanent tracheostomy?
*At 4th-6th tracheal rings
Why would you perform a tracheal resection?
*Tracheal stricture
*Tracheal stenosis
*Neoplasia
*Granuloma
