Respiratory: Bronchial Diseases Flashcards
(35 cards)
- Why may it not be appropriate to suppress a cough?
- Where are cough receptors?
- Coughing is a normal protective mechanism
- Present in the caudal oropharynx, larynx, trachea, tracheal bifurcation and bronchi- decreasing numbers towards the lungs
What are the three general causes of coughs- physiologically?
- Stimulation of cough receptors- laryngeal, tracheal, bronchial disorders
- Compression of bronchi- atrial enlargment, mass, lymphadenopathy
- Excessive fluids/mucus/inflammation
How can respiratory and cardiac causes of cough be distringuished?
- Heart rate and rhythm
- Increased sympathetic drive
- Tachycardia
- Absence of sinus arrhythmia
- Presence of abnormal heart sounds, time of coughing
Cats rarely cough due to cardiac disease
How can respiratory and cardiac causes of cough be distringuished?
- Heart rate and rhythm
- Increased sympathetic drive
- Tachycardia
- Absence of sinus arrhythmia
- Presence of abnormal heart sounds, time of coughing
Cats rarely cough due to cardiac disease
What is the single most useful thing to make an initial diagnosis of the cause of a cough and whether it is due to cardiac or resp?
Radiographs
What chamber of the heart will have apparent enlargment with cardiac disease?
Left Atrial enlargment
If the animal is in left sided heart failure what triad of signs will present on radiographs?
- LA enlargment
- Pulmonary venous distension
- Pulmonary infiltrate
What are the cardiac causes of LA enlargment ± left sided heart failure
- Acquired- mitral valve disease, DCM
- Congenital- VSD, PDA, mitral dysplasia
What is important to ascertain about a cough from clinical exam?
- Is the cough productive- may not be externally seen
- Signs of infection (pyrexia)- evidence of URT (lymph nodes)
- Change in respiratory rate/pattern
- When is the cough worse- night, day, exitement
- What does the cough sound like- goosehonk- tracheal collapse
What disease commonly causes a chronic cough in small and toy breed dogs?
Chronic bronchitis
- What is the definition of chronic bronchitis?
- What are typical radiographic findings?
- Coughing for over 2 of the last 12 months
- Thickened bronchial walls (cuffing)- doughnuts and tramlines
- What is the aetiology of chronic bronchitis?
- What characterises the syndrome?
- How is diagnosis confirmed?
- Unknown- environment play part
- Excessive mucus production, Goblet cell hyperplasia, bronchial mucosa inflammation, compromise to MC escalator, excess mucus- soft crackles, expiratory wheezes- bronchial narrowing
- Bronchoscopy and BAL fluid cytology
Why is bronchoscopy required to diagnose chronic bronchitis?
- Exclude tracheal/bronchial collapse
- See loss of normal glistening mucosal surfaces
- See thickened mucosa- difficult to see vessels (sometimes cobblestone)
- Excess of mucus
- How is BAL used to diagnose chronic bronchitis?
- How much saline is used?
- Cytology of BALF- typically mixed inflammatory infiltrate- macrophages, neutrophils- bacteria looked for
- 0.5ml/kg
Bacterial infection can play part but BALF usually sterile
If the animal is too small for a endoscope or GA is contraindicated what sampling techniques can be used for chronic bronchitis?
- Blind sampling through an endotracheal tube in an anaesthetised animal
- Trans tracheal wash- sedated, local- 14G between cartilages
What is the general managment of chronic bronchitis?
- Reduce weight if obese
- Avoid stimulating a cough- harness
- Avoid irritants
- Keep airway moist- avoid dry environments
- Warn owners- life long condition
What drugs can be used to treat chronic bronchitis?
- Bronchodilators- theophylline, salbutamol (inhaled)
- Glucocorticoids- anti-inflamm, reduce leucocyte accum, anti-fibrotic
- ABs- if positive culture
- Mucolytics- maybe-
- Antitussives- risky to supress productive cough- maropitant, diphenoxylate, loperamide
What is the definition of bronchomalacia?
Regional to diffuse dynamic airway collapse of segmental and/or subsegmental bronchi with associated clinical signs
What is the cause of bronchomalacia?
How is it diagnosed?
- Bronchial cartilage degeneration (chondromalacia)
- Results in dynamic bronchial collapse
- Typically small breed dogs- can be any
Diagnosis is based on bronchoscopy- recognition of the dynamic airway collapse of bronchial lumen
How is bronchomalacia managed?
- Control of the cough- supressents- codine phosphate
- Bronchodilators
- Weight managment
- Avoiding collar
What is chronic trachoebronchial syndrome?
How is it resolved?
- Term reserved for coughing dog where the pathological changes are minimal
- Typically- chronic coughing dogs with initial diagnosis of kennel cough
Most cases respond to anti-inflammatory doses of prednisolone
- What is bronchiectasis?
- How is it managed?
- Dilated bronchi with bronchoscopy confirming being full of mucopurulent material
- Chronic ABs, if one lobe involved, lobectomy
May be complication of bronchial diseases
- What is bronchiectasis?
- How is it managed?
- Dilated bronchi with bronchoscopy confirming being full of mucopurulent material
- Chronic ABs, if one lobe involved, lobectomy
May be complication of bronchial diseases
- What is primary ciliary dyskinesia?
- What is required for diagnosis?
- What does it therefore lead to?
- What breeds can be affected?
- What else can patients be asccoated with?
- Cilia of the airways may be abnormal resulting in abnormal microtubule arrangment or gross ciliary disarray
- Diagnosis relies on electron-microcopic identification of microtubule abnormalities or semen sample (repro cilia affected)
- Lack of mucus clearance- high risk of bacterial infection- bronchopneumonia
- English springers, pointer, old english sheepdog, sharpei, bichon frise, newfoundland
- Situs inversus- left right reversal of thoracic/abdominal organs (spleen on right)
