PATHOLOGY - Small Animal Upper Respiratory Disease Flashcards
What is stridor?
Stridor is a harsh, high pitched sound heart on inspiration which will resolve at rest/sleeping
What is indicated by stridor?
Stridor indicates upper airway obstruction and laryngeal paralysis
What is laryngeal paralysis?
Laryngeal paralysis is when their is failure of the dorsal cricoarytenoid muscle resulting in the glottis being unable to abduct during inhalation
What are the four clinical signs of laryngeal paralysis?
Stridor
Dysphonia
Gagging and coughing when eating and drinking
Exercise intolerance
What are the four clinical signs of an acute crisis of laryngeal paralysis?
Severe dyspnoea
Stridor
Cyanosis
Collapse
Which can trigger an acute crisis of laryngeal paralysis?
Excitement
Heat
Stress
Exercise
How do you diagnose laryngeal paralysis?
You diagnose laryngeal paralysis by visualising the larynx as the patient is recovering from anaesthesia. You cannot diagnose this while the patient in under anaesthesia, as all anaesthetic drugs will supress laryngeal function which could result in a false positive
How do you treat and manage an acute crisis of laryngeal paralysis?
Oxygen supplementation
Sedation
Steroids
Cooling
What should you do if your patient is not improving following supportive care for an acute crisis of laryngeal paralysis?
If your patient is not improving, consider surgical intervention or do an emergency tracheostomy
Have a conversation with the owner about this, and be aware that the surgery is very risky and can affect quality of life - especially as these tend to be older dogs
Which two surgical procedures can be done to treat laryngeal paralysis?
Cricoarytenoid lateralisation (tieback) surgery
Partial arytenoidectomy
What lifestyle changes have to be made following surgical correction of a laryngeal paralysis?
- Animals should be encouraged to eat slowly and drink only water, as there is a high risk of aspiration pneumonia
- Animals will not be allowed to swim as there is a high risk of aspiration pneumonia
- Use a harness rather than a lead
What are the three main causes of laryngeal paralysis?
Idiopathic
Congenital
Secondary to other diseases
What signalement is prone to idiopathic laryngeal paralysis?
Old, medium to large breed dogs
Which dog breed is predisposed to laryngeal paralysis?
Labrador Retreivers
List six factors which can cause secondary laryngeal paralysis
Damage to the recurrent laryngeal nerve
Trauma
Myopathy
Neuropathy
Neoplasia
Hypothyroidism
Which surgical procedure can cause damage to the recurrent laryngeal nerve and subsequent laryngeal paralysis?
Thyroidectomy
What is stertor?
Stertor low pitch, snoring sound that worsens during excitement and sleeping
What is indicated by stertor?
Brachycephalic airway obstruction syndrome (BOAS)
What are the primary anatomical components of brachycephalic airway obstruction syndrome (BOAS)?
Stenotic nares
Elongated soft palate
Excess pharyngeal mucosa
Aberrant turbinates
Hypoplastic trachea
What are aberrant turbinates?
Aberrant turbinates are structural defromaties where the nasal turbinates extend beyond their normal anatomical limits
In which brachycephalic breed are hypoplastic tracheas more commonly seen?
Bulldogs
Which secondary conditions are seen as a result of brachycephalic airway obstruction syndrome (BOAS)?
Everted laryngeal saccules
Tonsillar hyperplasia and eversion
Laryngeal collapse
Regurgitation
Hiatal hernia
What is a hiatal hernia?
A hiatal hernia is when part of the stomach herniates into the thorax
What are the main consequences of brachycephalic airway obstruction syndrome (BOAS) that influence day to day life?
Inflammation and soft tissue thickening
Increased respiratory effort
Stertor
Regurgitation and aspiration
Exercise intolerance
Dyspnoea
Cyanosis
Heat intolarance
Collapse
Risk of death
How does brachycephalic airway obstruction syndrome (BOAS) cause inflammation and soft tissue thickening?
Brachycephalic airway obstruction syndome (BOAS) results in turbulent airflow due to the anatomical abnormalities. This turbulent airflow causes inflammtion and subsequent soft tissue thickening which will worsen the airway obstruction and turbulent airflow
How does brachycephalic airway obstruction syndrome (BOAS) cause heat intolerance?
The nasal cavity plays a central role in an animal’s ability to regulate their temperature, in animals with brachycephalic airway obstruction syndrome (BOAS), their nasal cavity is obstructed and thus they are unable to carry out adequate heat exchange. These animals will thus be heat intolerant, which will increase their oxygen demand and worsen their condition
Why does brachycephalic airway obstruction syndrome (BOAS) increase the risk of aspiration?
Brachycephalic airway obstruction syndrome (BOAS) increases regurgitation which will increase the risk of aspiration and thus aspiration pneumonia
What is the key clinical sign of an acute episode of brachycephalic airway obstruction syndrome (BOAS)?
Severe dyspnoea
How do you manage an acute episode of brachycephalic airway obstruction syndrome (BOAS)?
Oxygen supplementation
Sedation
Cooling
Administer steroids
What method of oxygen supplementation should you use for acute episodes of brachycephalic airway obstruction syndrome (BOAS), and why?
Flow-by oxygen is the best method as it is the least stressful for your patient so you reduce the risk of stressing the patient out and worsening their dyspnoea
Which sedative is recommended for patients suffering from an acute episode of brachycephalic airway obstruction syndrome (BOAS)?
Butorphanol
Why should you administer steroids to patients suffering from an acute episode of brachycephalic airway obstruction syndrome (BOAS)?
Steroids should be administered as brachycephalic airway obstruction syndrome (BOAS) causes inflammation and soft tissue thickening and steroids reduce inflammation
What should you do if your patient is not improving following supportive care for acute brachycephalic airway obstruction syndrome (BOAS)?
If your patient is not improving, consider putting them under anaesthesia and intubating them, or do an emergency tracheostomy
Have a conversation with the owner about this, and be aware there is a chance the animal may not recover from anaesthesia
What advice should you give to owners to manage brachycephalic airway obstruction syndrome (BOAS)?
Weight loss
Use a harness rather than a lead
Short walks in the morning and/or evening (when it is cooler)
Minimise stressors
Consider surgical intervention
What are stenotic nares?
Stenotic nares are caused by the collapse of the dorsolateral cartilages after birth
Which surgical intervention can be done to correct stenotic nares?
Wedge resection
At what age can you do a wedge resection?
You can do a wedge resection from 3 to 6 months old
How do you diagnose an elongated soft palate?
You diagnose an elongated soft palate by visualising the soft palate under anaesthesia
Which surgical intervention can be done to correct an elongated soft palate?
Soft palate resection
How does brachycephalic obstructed airway syndome (BOAS) cause eversion of the laryngeal saccules?
Brachycephalic obstructed airway syndrome (BOAS) causes an increased respiratory effory which will generate a negative pressure which will evert the laryngeal saccules
Which surgical intervention can be done to correct laryngeal saccule eversion?
The laryngeal saccules can be removed however this is not always done
How does brachycephalic obstructed airway syndome (BOAS) cause laryngeal collapse?
Brachycephalic obstructed airway syndrome (BOAS) causes an increased respiratory effory which will generate a negative pressure which can cause laryngeal collapse
Which two surgical procedures can be done to correct laryngeal collapse?
Cricoarytenoid lateralisation (tieback) surgery
Partial arytenoidectomy
What are feline polyps?
Feline nasopharyngeal polyps are benign inflammatory growths of connective tissue that arise from the mucosal lining of the tympanic bulla and extend into the external ear canal - known as an aural polyp - or extend into the nasopharynx - known as a nasopharyngeal polyp
What are the clinical signs of nasopharyngeal polyps?
Stertor
Dysphagia
Unilateral nasal discharge
Which surgical procedure can be done to correct nasopharyngeal polyps?
Traction evulsion
Which ten questions can be useful to ask when gathering a history when an animal presents with nasal discharge?
Has this nasal discharge been acute or chronic?
Is the nasal discharge uni- or bilateral?
What is the nature of the discharge?
Has your pet been sneezing or reverse sneezing?
Has your pet been coughing?
Has there been any head shyness or reluctance to eat?
Has your pet been pawing at or rubbing their face on the ground?
Is there a history of dental disease?
Has there been any trauma?
Vaccinations/worming?
Any recent travel?
When is nasal discharge classified as acute or chronic?
Nasal discharge is acute is it has been going on for less than three weeks, and it is chronic if it has been going on for more than three weeks