Coughing

Question 1

What other clinical signs can be mistaken for coughing?

Answer 1

Comiting
Regurgitation
Reverse sneezing
Retching
Stridor/stertor sounds

Question 2

What is coughing?

Answer 2

Protective mechanism of URT
Forceful expelling of air

Question 3

Causes of ACUTE coughing

Answer 3

CIRD/tracheobronchitis
irritation by smoke/dust
Airway FB
Pulmonary haemorrhage
Acute pneumonia
Acute oedema
Airway trauma

Question 4

What is CIRD?

Answer 4

Canine Infectious Respiratory Disease
Caused by:
* Canine parainfluenza virus
* Canine adenovirus -2
* Bordetella bronchiseptica

Question 5

What are anti-tussives?

Answer 5

Anti cough medication
Shouldn’t use if coughing is productive
Useful if non-productive e.g. neoplasia
Butorphanol/codeine

Want to keep cough response as it protects the airways

Question 6

Causes of CHRONIC coughing

Answer 6

Chronic bronchitis/bronchiectasis
Airway F.B.
Bronchopneumonia
L. heart failure
Oslerus/Aelurostrongylus infestation
Tracheal collapse
Pulmonary neoplasia - primary or secondary
Extra-luminal mass lesions - thyroid, abscess, lymphoma
Eosinophilic disease – EBP/PIE/allergic airway disease
(Pulmonary “fibrosis”)

Question 7

What will you see on a radiograph with chronic coughing?

Answer 7

Bronchial patterns (tramlines and donuts)
Lsided heart failure (cardiomegaly)
Foreign body potentially

Question 8

Canine Chronic Bronchitis

Answer 8

Coughing for >2 months
Characterised by:
* neutrophilic/eosinophilic infiltration of mucose and thickening of smooth muscle
fibrosis of lamina propria
Increased goblet cell size and number
Loss of ciliated epithelial cells

Question 9

Secondary complications to canine chronic bronchitis

Answer 9

Thickening of bronchial tissue
Over production of airway mucus
Narrowing of airways
Airway collapse due to wall weakaness (bronchomalacia)

Question 10

Clinical signs of canine chronic bronchitis

Answer 10

Wheezing
Productive coughing, worse on excitement
Typical in small/toy breeds
Often obese

Question 11

How to diagnose canine chronic bronchitis

Answer 11

History/clinical findings
over exaggerated sinus arrhythmia
coughing
Increased bronchial pattern on radiographs
Red and raw on bronchoscopy
BAL - increased mucus with inflammatory cells

Question 12

Management of chronic bronchitis

Answer 12

Can’t cure unless find underlying cause
General control:
* Weight control
* No collars
* Steam in bathroom
* avoid dry environments
Glucocorticoids - oral or inhaled
Bronchoddilators
Coupage

NOT NSAIDs
NOT ANTITUSSIVES

LONG TERM TREATMENT
DOG WILL ALWAYS HAVE A COUGH

Question 13

Examples of bronchodilators

Answer 13

Terbutaline
Theophylline
Salbutamol

Beta 2 agonists

Question 14

Benefits of bronchodilators

Answer 14

• Reduce spasm of lower airways
• Decrease intrathoracic pressures
• Decrease tendency of larger airways to collapse
• Improve diaphragmatic function
• Improves muco-ciliary clearance
• Inhibit mast cell degranulation (reduced release of mediators of bronchoconstriction)
• Possible additional ways that signs are improved:
  ○ Improves pulmonary circulation
  ○ Improves cardiac function
  ○ Reducing respiratory effort

Question 15

Examples of corticosteroids

Answer 15

Fluticasone
Beclomethasone

Question 16

Benefits of corticosteroids

Answer 16

• Broncho-dilatory
• Anti-inflammatory
  ○ Inhibit both prostaglandin & leukotriene synthesis
• Reduce leukocyte accumulation
• Reduce vascular permeability
• Alter macrophage function
• Inhibit fibroblast growth
• Modulate the immune system
• BUT adverse side effects
  ○ Dose limiting

Question 17

Advantages of inhaled medications

Answer 17

• Management of chronic airway disease
• Minimal absorption into systemic circulation
  ○ Less systemic effects
• Faster onset of action
• Dose of glucocorticoid is lower
• Effective in acute situations

Question 18

Disadvantages of inhaled medications

Answer 18

Expensive
Time consuming
Owner and patient compliance issues

Question 19

What is feline bronchial disease

Answer 19

AKA Feline asthma, feline allergic airway disease
* Type I hypersensitivity condition to inhaled allergens

Question 20

Common causes of bacterial bronchopneumonia

Answer 20

(Primary infection is rare)
○ E Coli
○ Klebsiella
○ Pasteurella
○ Staphs
○ Streps
○ Mycoplasma

Question 21

Predisposing factors to bacterial bronchopneumonia

Answer 21

○ Debilitation
○ Prolonged recumbency
○ Systemic immunosuppression
○ Defective respiratory defences
○ Damaged respiratory epithelium
○ Aspiration
○ Airway obstruction
○ Systemic sepsis

Question 22

Clinical signs of bacterial bronchopneumonia

Answer 22

Cough
Respiratory distress
Ex intolerance
○ More severe infections may produce hyperthermia
○ Anorexia and lethargy are common signs
○ Increased or decreased lung sounds may be present, may include crackles
○ Respiratory distress and cyanosis may develop in severe cases

Question 23

Diagnostic approach to bacterial bronchopneumonia

Answer 23

CBC
Biochemistry
thoracic radiographs (alveolar pattern)
Airway sampling (culture and cytology)