Coughing Dogs and Cats Flashcards
Best diagnostic test for coughing patient?
Thoracic radiographs
Most common cause of acute coughing in dogs?
Infectious Tracheobronchitis (ITB)
- if hx and PE consistent with this then tx as if it is
- if clinical signs not consistnet then further investigation indicated
Causes of acute coughing
- infectious tracheobronchitis
- airway irritation
- FB
- pulmonary haemorrhage
- acute pneumonia
- acute oedema
- airway trauma
Define acute and chronic coughing
- artificial distinction
> acute = sudden onset, does not persist for more than 2-3 weeks
Causes of chronic coughing ?
- chonric chronchitis (tracheobronchial syndrome)
- cardiac disease
- parasites
- tracheral collapse
- FB
- bronchopneumonia
> rarer: - pulmonary neoplasia
- extra-lumenal airway comression
- eosinophilic disease (PIE, FAAD)
- pulmonary fibrosis
- pleural diseasse
- ciliary dyskinesia
What is chronic bronchitis?
> clinical syndrome - chronic irritation to bronchial mucosa - mucosal hyperplasia - ^ mucous production - v efficacy of resp defence mechanisms - inflammation/2* infection - bronchospasm - v airflow - chronic cough > underlying cuase usually unknown (smoking, pollutants etc.)
Signalment and Hx of chornic bronchitis?
- typically old, small breed, overweight
- insidious onset, dry hacking cough
- rarely hx of known precipitating cause
- cough paroxysmal and usually unproductive
- exacerbated by excitement/excercise, pulling on lead, change in environmental temperature or humidity, times of day
PE findings of chronic bronchitis
- otherwise NAD
- often slightly overweight
- ^ bronchial noise/wheezes on auscultation
- cough easily elicited on tracheal pinch
- sinus arrhythmia may be exaggerated
- absence of murmur help to rule out cardiac cause of cough
How can chronic bronchitis be diagnosed?
- diagnosis of exclusion
- bloods normal
- radiography (^ bronchial markings, but maybe false +/-)
- endoscopy (irregular airways and mucous hypersecretion)
- tracheobronchial wash (chronic inflammation +- positive culture, probably 2*)
Can you completely eradicate chronic bronchial disease?
No! Try to minimise coughing so it isnt debilitating to patient
what can be seen on rads with chonric bronchial inflamamtion?
tramlines and donuts
Aims of tx of chronic bronchitis?
- management alterations > avoid smoke, dust > humidify air > maintain weight > avoid pressure on neck - drug therapy possibly (not chroniccally) > bronchodilators > Antibiotics > Expectorants and mucolytics > cough suppressants > Anti-inflammatory
Types of bronchodilators
> Xanthines - theophylline > beta-2 agonists - terbutaline (bricanyl) - adreanaline > anti-muscarinics - atropine (multiple other effects ay preclude use)
Types of anti-tussives. WHen are antitussives good?
> opiate derivatives (NB. side effects eg. sedation, constipation)
- butorphanol (torbutrol)
- codeine
- Good for NON-productive coughs (tracheal collapse, bronchial compression)
- Not indicated if alveolar pattern seen on rads
Bromohexine (Bisolvon)
- mucolytics
Advantages and disadvantages of anti-inflammatorys?
> Corticosteroids (low dose)
+ imprived clinical signs and QOL
- too effective
- animal and owner become depednnt on tx
- iatrogenic hyperadrenocorticism develops
-> overweight -> worsening resp disease
give inhaled to v side effects
Side effects of bronchodilators?
- tachycardia
- excitability
(eg. xanthines = caffeine)
SIde effects of expectorants?
^ productiveness of cough
Side effects of corticosteroids?
-Iatrogenic HAC signs
Side effects of cough suppressants?
- trapping airway secretions
- sedation
What is the main problem with chronic bronchitis?
More annoying for owner - not that bad for dog! Can live long happy life
What is FAAD?
Feline ALlergic Airway Disease (= Feline Asthma)
- most common cause of persistent coughing in cats
- Antigenic stimulation -> inflam, mucous, oedema, bronchoconstriction
- Airway hyperreactivity, smooth mm hyperplasia and airway narrowing result
Hx and PE of FAAD?
- intermittent dyspnoea and coughing
- acute life threatening bouts
- rarely identifiable stimulus
> PE - may be normalbetween bouts
- ^ resp effort
- expiratory wheezes
- hyperinflation of lung
Diagnostics of FAAD?
- Bloods: Eosinophilia
- Rads: bronchial pattern and hyperinflated lung
- trach wash: inflammatory cells, predominantly eosinophils - R/O parasites and 2* bacterial infection
Emergency Tx of FAAD?
- oxygen
- rapid acting corticosteroid eg. methylprednisolone succinate
- bronchodilator (atropine/adrenaline)
Chronic maintainence of FAAD?
- corticosteroids tapered to lowest effective dose (nebulise)
- bronchodilators (terbutaline, theophylline etc.)
- other ways of controlling inflammatory process (cyproheptadine, LT inhibitor? unlicensed but may have some success)
Prognosis of FAAD?
- variable
- some cats stabilise: find best tx for individual
- some cases cannot be controlled and may die acutely
- chronic, long term commitment!
What is THE feline lungworm?
Aeluostrongylus
What disease does aelurostrongylus cuase? Tx?
- alveolar/interstitial disease (LRT with eosinophilia)
- fenbendazole tx
Which parasites can affect the respiratory tract of dogs? Which is most common?
- Angiostrongylus vasorum*
- Filaroides (Oslerus) Osleri
- Dirofilaria
> Young animals affected
What is angiostrongylus? Intermediate host?
Lungworm, slug
History signs of lungworm?
- Chronic cough unresponsive to convential tx
- coagulopathy (angiostrongylus)
- dyspnoea/wheezing
- coughing up blood
PE findings of lungworm? Diagnostics?
- no specific findings on physical
> Dx - Haem = Eosinophilia
- Feacal exam or TTW = Larvae
- Rads = broncho/alveolar infiltration, nodular interstitial pattern, pulmonary hypertension, nodules at tracheal bifurction with filaroides)
- bronchoscopy = tracheal nodules (filaroides)
Is filaroides more or less common than angiostrongylus?
filaroides much less common than angiostrongylus
What pattern is typically seen with Angiostrongylus Vasorum?
- Air bronchograms
- Peripheral cloudy interstitial pattern with clear central area of lungs
What new test is available for detection of angiostrongylus vasorum?
Snap test by IDEXX
- intravascular parasite
> BUT may be subclinical angiostrongylus not related to clinical signs if this test is too sensitive!
Tx of lungworm?
> fenbendazole 7d tx all types of respiratory parasite
> recent licensing of milbemycin and moxidectin for angiostrongylus
Prognosis of lungworm?
- prognosis generally good
- some present so severely that they die before you can treat
- pulmonary vascular remodelling: Pulmonary hypertension and R heart disease (similar to dirofilaria immitus)
Pathophysiology of tracheal collapse
- loss of normal structure of tracheal rings
- dorsal ligament stretches and trachea loses normal cylindrical structure
- dynamic variation in tracheal diameter occurs
- cervical trachea collapses on INSPIRATION
- thoracic trachea collapses on EXPIRATION
- > cough and dyspnoea (insp/exp/both)
History and PE findings of tracheal collapse?
- Yorkshire terriers and poodles
- chronic cough with gradual progression
- quacking or honking cough
- may progress to severe dyspnea sometimes
> PE - Normal
- clicking sound when they breath (dorsal ligament)
- tracheal malformation may be palpated
- elicit cough on palpation
What diagnostics may be useful for tracheal collapse?
- fluoroscopy and endoscopy (dynamic problem, may not be seen on rads)
How is tracheal collapse graded?
1-4 1 = slight dip 2 = semilunar shape 3 = banana shape 4 = inverted trachea
Tx of tracheal collapse
- medical management
- similar to chronic bronchitis esp. cough suppressant
- surgery available, ^ risk, only for v severe cases
> intralumenal stent
> rings round outside
Tx of pulmonary neoplasia?
1* without spread = can be resected, prognosis ok
2* or 1* with spread = poor prognosis
What neoplasm commonly metastasises to the lungs?
Sarcoma
Hx with 1* neoplasia
- may be no clinical signs (found incidentally)
- cough
- haemoptysis
- weight loss
- rarely dyspnoea
PE with 1* kung neoplasia
- may be normal
- may be assymmetric
- movement of apex beat
- unilateral v in resonance
- unilateral ^ resp noise
Methods of definitive diagnosis of pulmonary neoplasia?
> Radiography
- solitary soft tissue density
- Ddx: neoplasia, granuloma, abscess, cyst, haematoma
CT better resolution
Bronchoscopy and trach wash
- unlikely to be hepful unless affecting major airway or v exfoliative
Trucut / FNA biopsy if mass superficial
Tx pulmonary neoplasia?
- mass small and no mets = surgery, lobectomy (but ^ incidence recurrence)
- adjunctive chemo possible (not much evidence)
Is 1* or 2* neoplasia more common in the lungs? Ddx?
2*
- similar clinicalsigns and diagnostic findings but likely to be multiple masses
- Ddx: granulomatous disease, parasitic, deep fungal disease, TB
Tx 2* neoplasia in lungs?
Not appropriate
- short term palliation of clinical signs
How may FBs present with resp disease?
- acute onset associated with recognised event eg. excercise in autumn with grass awns present
(NB: kennel cough infectious tracheobronchitis highest incidence in autumn too) - do not respond to tx with ABx or antiinflams (though may respond sporadically)
- halitosis as object rots
PE FB findings
- normal
- intermittent pyrexia
- localised ^ resp noise
- focal area of dullness on percussion
Diagnostics for FB?
- radiography (focal involvement one lung lobe often caudal right lobe in dogs)
- endoscopy for visualisation and retrieval
Tx FB?
Removal!
- but may have fragmented and be irretreivable
- Surgical removal may be necessary +- partial/complete lobectomy at same time
What is PIE?
- pulmonary infiltrate with eosinophils
- syndrome in dogs
- may be immune mediated (allergic) cause
- hx chronic cough unresponsive to ABx
- may be seasonal
- may be association with other allergic disease eg. atopy
Dx PIE?
- eosinophilia
- rads: bronchial/alveolar pattern
- bronchoscopy: ^ mucous in airways
- airway washes: eosinophils
- NB: May be 2* bacterial infection and neutrophilic inflammation
Tx and prognosis of PIE?
- control 2* infection
- corticosteroids at immunosupressive doses (taper to lowest effective dose) potentially wean off altogether
- prognosis excellent for control of clinical signs
> May require prolonged/lifelong tx with risk of iatrogenic HAC (cushings)
see notes for table of conditions causing coughing
