Coughing in SAs Flashcards
Name some presenting signs typically seen in patients with respiratory tract disease.
A.Changes in rate or character of respiration – dyspnoea, tachypnoea, hyperpnoea, orthopnoea
–Dysnpnoea – some clinicians do not like this as subjective about not being able to get their breath but we don’t know if out patients can or not
B. Coughing.
OTHERS INCLUDE:
C. Sneezing/nasal discharge
D. Respiratory noise.
– URT disease make a lot of noise if they are clinically affected
E. Cyanosis.
–Look at MM colour in light of everything else going on
F. Others.
- Weight loss.
- Collapse/syncope.
- Changes in “voice” - laryngeal lesions.
- Exercise intolerance.
- Facial deformity.
Most present with respiratory difficulty or coughing.
When presented with a coughing animal, what do you need to make sure you differentiate it from? i.e. what things can sound the same
- Cough
- Sneeze
- Retch
–Is it definitely a cough? It could also be a retch!
- URT disease – laryngeal/pharyngeal
- Dysphagia
- Nasal/pharyngeal/respiratory tract
- May have to describe it for the owner to try to distinguish whether it’s a cough or a retch etc. (Malcolm does some real good noises here, give it a listen back)
What is a cough?
Why do we cough generally?
- Inhaled, tried to expel the air that was inhaled
- Closed glottis, then glottis opens, abdominal and thoracic muscles force air out
- Why do we cough? Protective mechanism stimulated by irritation (physical or chemical) as there are receptors in the airway that detect this irritation, receptors found everywhere in lungs apart from alveolus.
- Coughing generally means some irritation of the airway. However, cats can have severe pulmonary oedema and they wont cough..
What are some common causes of ACUTE coughing?
- Acute = onset within a few days
- Tracheobronchitis - “kennel cough”
- Irritation by smoke/dust/chemicals/medicines!
- Airway FB - may have been in there some time. With some inhaled FB, it can be a constant cough.
- Pulmonary haemorrhage - often + dyspnea – significant lung involvement
- Acute pneumonia, e.g. inhalation - often + dyspnoea
- Acute oedema - often + dyspnoea
- cardiogenic/non/cardiogenic
• Airway trauma - choke chains/bites etc.
What is infectious tracheo-bronchitis?
Kennel cough
What are some causes of tracheo-bronchitis (kennel cough)?
•Variety of causes including
–Canine parainfluenzavirus
–Canine adenovirus (2)
–Bordetella bronchiseptica
What vaccines are available for infectious tracheo-bronchitis?
- Bordetella bronchiseptica – live by intranasal
- Canine parainfluenzavirus – live by injection
- Canine adenovirus (2) – live by injection
How long can it take to recover from infectious tracheo-bronchitis?
Spontaneous recovery – 7-10 days
When should you use systemic antibacterial agents for infectious tracheo-bronchitis?
–If pyrexic
–If systemically ill
–Muco-purulent nasal discharge
–All of the above would increase index of suspicion of secondary bacterial involvement for which antimicrobials MIGHT be indicated. However, most of these dogs are WELL
What is unproductive retching a characteritis of?
Kennel cough
What can bordetella bronchiseptica cause?
What are some treatments for it?
- Puppies, especially groups
- URT/nasal infection – bronchopneumonia.
- Can be fatal disease
–Tetracyclines (NB teeth)
–Clav-ptd amoxicillin
–Ptd sulphonamides
What are anti-tussives? Give an example
When should we use them?
•Don’t use cough suppressants unless absolutely necessary – as coughing IS protective in most cases
–Value particularly in anatomical airway disease
–Intractable non-productive pathological cough – primary lung tumour for example, then it is okay to use anti-tussive for this
–Want animal to cough material out from within its airways! So try not to use them for kennel cough etc.
–do use them is structural airway disease
•Butorphanol
What are some common causes of ACUTE COUGHING?
- Tracheobronchitis - “kennel cough”
- Irritation by smoke/dust/chemicals/medicines!
- Airway FB - may have been in there some time.
- Pulmonary haemorrhage - often plus dyspnoea.
- Acute pneumonia, e.g. inhalation - often plus dyspnoea.
- Acute oedema - often plus dyspnoea.
- cardiogenic/non/cardiogenic
• Airway trauma - choke chains/bites etc.
What are some common causes of CHRONIC COUGHING - in DOGS?
Chronic bronchitis/bronchiectasis
– degenerative condition
• L. heart failure
– degenerative condition
- Oslerus /Aelurostrongylus infestation
- Tracheal collapse
– degenerative
- Airway F.B.
- Bronchopneumonia
– infectious
- Pulmonary neoplasia - primary or secondary
- Extra-luminal mass lesions - thyroid, abscess, lymphoma
- Eosinophilic disease – EBP/PIE/allergic airway disease
– inflammatory
- (Pulmonary “fibrosis”)
- (Pleural irritation)
What is canine chronic bronchitis?
What is it characterised by?
- Daily coughing for >2months. Often has been for months and months!
- Characterised by
–Neutrophilic/eosinophilic infiltration of mucosa and thickening of smooth muscle later, fibrosis and scarring of lamina propria
–Increased goblet and glandular cell size and number
–Oxidative injury and inflammatory products damage cells and lead to mucus hypersecretion
–Loss of ciliated epithelial cells and failure of mucociliary clearance and debris
- Structural change in lining of airways – neutrophilic infiltration and leads to scarring, so loses structural integrity and lining fails to produce and move normal mucus as it should do. Mucus that is produced is abnormal in quantity and quality. Physically structurally ABNORMAL AIRWAY. This animal will NOT get better, once this process has begun – this lining is damaged for good and this animal will have the problem for the rest of its life
The combination of events in canine chronic bronchitis leads to what?
What clinical signs does this cause?
- The combination of these events leads to thickening of bronchial tissue, overproduction of airway mucus and narrowing of the airways (particularly terminal bronchi)
- Leads to clinical signs of wheezing and productive coughing
- Looking down at airways of this disease – airways are distorted and there are degrees of collapse when the animal breaths in or out. Coughing, unproductive, wheezing on auscultation due to this narrowing of the airways
What is the aetiology of canine chronic bronchitis?
–Often seen secondary to underlying conditions
- Tracheal collapse, chronic barking
- FB
- Previous infections or inhalant toxins
- Environmental factors
- Chronic smoke inhalation/noxious gas or particle rich environment
How do dogs with canine chronic bronchitis present?
What breed is it most common in?
•Typically seen in small / toy breeds
–Although can see in any age/breed
- Worse on excitement
- Harsh cough with attempts at production
–Usually clear/frothy, yellow suggests infection
–But very often they cough nothing up
•Usually externally well, often obese
–Excessive weight causes these animals to be worse
–Occasionally pant excessively
–Tracheal pinch positive
•If it doesn’t cough, doesn’t mean it doesn’t have airway disease!! But tells us about the nature of the cough
–Crackles and expiratory wheeze on auscultation of the lungs if very severe
- Exaggerated expiratory phase – but this is quite rare, as they are usually well dogs that just cough a lot
- Expiratory push due to airway narrowing
How do we diagnose chronic canine bronchitis?
•Typical history, physical findings
–Often exaggerated sinus arrhythmia
•Thoracic Radiographs
–Increased bronchial lung pattern
- Bronchoscopy and BAL
- Sinus arrhythmia – more difficult getting air out, resp cycle is more exaggerated, so more exaggerated sinus arrhythmia.
- If normal sinus arrhythmia (regularly irregular), a heart murmur is not causing the clinical signs if they do have a heart murmur
What is wrong here?
What are the blue arrows pointing to?

Chronic bronchitis
If reasonably okay on radiograph, they may not be severe enough for us to see anything – could still be airway disease though.
Arrows: can see airways going to cranial lung lobes, can see both walls of airways and this is far too wide at this point.
Describe the findings of this radiograph

- Chronic bronchitis
- Severe dilated airways
- Can see some doughnuts
- Need to take good quality thoracic radiographs, can always send off to someone to interpret but need a good picture to begin with
- This is a good inspiratory radiograph
With canine chronic bronchitis, what does a BAL show?
•BAL results typically show:
–Increased mucus
–Non-degenerate neutrophils, eosinophils and macrophages
–Cushmann’s spirals (airway mucus casts)
–Presence of bacteria / particulate matter are less common and if present would suggest underlying cause present. Rarely do we see bacteria, mainly evidence of chronic inflammatory change
What are some newer, molecular methods for identifying the presence of inflammatory change?
•Newer molecular methods for identifying the presence of inflammatory change, but not currently commonly available
–Upregulation of proteins in CB and IPF dogs
•β-actin, complement C3, α-anti-trypsin, apolipoprotein A-1, haptoglobin and transketolase
–No difference between CB and IPF dogs however
•Pro-collagen III concentration lower in BALF in CB than EBP and IPF
–Marked upregulation of mucin gene expression in tracheobronchial brushing specimens in CB compared to control dogs
What are some managements for chronic bronchitis?
•General management:
–Weight control
–Harness rather than collar / lead
–Avoid irritants / smoking environment
–Unlikely this dog will ever stop coughing!
•Mucous is easier to shift if hydrated
–Avoid very dry environments
–Nebuliser – rarely do that to these animals
–Steam in the bathroom steam things mucus out and helps animal get rid of it – but warn owner they will cough more afterwards as the mucus will be easier to cough up and this is a good thing.
