Bronchial Diseases Flashcards
What does the cough reflex do?
- Removes accumulates mucous
- Assists mucocilliary clearance
- Expels inhaled particulate material
- Protects against inhaling particles
What receptors help with coughing?
- Mechanoreceptors - in larger airways
- Chemoreceptors - in medium airways
- none in bronchioles or alveoli
What are Ddx for coughing?
- Compression of mainstem lobar bronchi
- Stimulation of cough receptors
- Excessive mucus / fluid / inflammation
What can cause compression of mainstem lobar bronchi?
– Left atrial enlargement
– Tracheobronchial / Bronchial Lymphnode enlargement
– Neoplasia
What can cause stimulation of cough receptors?
- Laryngeal disorders
- Tracheal disorders
- Bronchial disorders
What can cause excessive mucus/ fluid/ inflammation?
– (usually soft / moist / ineffectual cough)
– Pneumonia
– Bronchopneumonia
– Pulmonary oedema
What occurs with HR, heart rhythm with cardiac disease?
- Normal or increased HR
- Regular sinus rhythm, sinus tachycardia or arrhythmias
What occurs with HR, heart rhythm with respiratory disease?
- normal or decreased HR
- Sinus arrhythmia (unless v stressed)
What history should be collected with a coughing patient?
- Environment
- Worming history
- Travel history
- Recent events / illnesses / changes
- Any other signs?
- How long coughing?
- Onset?
- Description of the cough. When worse?
- Is the cough really a cough?
- Any change in bark?
- Does the dog sleep normally?
What should be done on clinical exam?
- Observation (respiratory rate / pattern / any dyspnoea /
any spontaneous coughing) - Detailed clinical examination
- Listen to all lung areas during normal quiet (non-panting) respiration. Identify adventitious respiratory
sounds. - Listen to and palpate upper respiratory tract
- Percussion
- Thoracic compressibility (cats)
- Attempt to induce a cough – auscultate following cough
What characterises chronic bronchitis?
- Excessive mucus production
- Increased goblet cell numbers
- Hyperplasia of submucosal glands
- Damage to cilia
- Loss of ciliated epithelium
- Squamous metaplasia of mucosa
- Secondary infections = common
What breeds are more susceptible to chronic bronchitis? how is the disease treated?
- Small breed / toy breed dogs
- Guarded prognosis - irreversible change - aim is to manage condition
What investigation should be done?
- Thoracic radiographs
- Haematology
- Bronchoscopy
- Bronchoalveolar lavage to obtain samples for cytology / bacteriology / parasitology
When is bronchial collapse seen?
- May be secondary to other primary respiratory conditions
- Chondromalacia
- Wheezy cough
- Not just small breed dogs
What are respiratory parasites in small animals?
- Oslerus (Filaroides) osleri - forms nodules (=collapse)
- Crenosoma vulpis (fox lung worm) - seen on tracheobronchoscopy
- Aelurostrongylus abstrusus (cats)
How much fluid should you use for a BAL?
- about 0.5ml / kg
- Should be able to aspirate 50% of fluid
What cells would be seen on BAL cytology?
- Ciliated columnar epithelial cells
- Goblet cells
- Macrophages (70%)
- Neutrophils (20%)
- Lymphocytes (10%)
- Eosinophils (<20-25%)
- Simonsiella = oral contamination
What is seen on BAL cytology of chronic bronchitis?
- Cytology:
- Increased mucus ++
- Increased neutrophils, macrophages
- Possibly squamous metaplasia of normal ciliated
columnar epithelial cells (CCECs) - Presence of bacteria / particulate matter
- Submit for Bacteriological culture
How would you manage chronic bronchitis?
- Weight control
- Harness>collar/lead
- Avoid irritants / smoking environment
- Excess of Mucus!
- Mucus is easier to shift if hydrated
- Avoid very dry environments (CH)
- Nebuliser
- Spend time in bathroom during owners
shower / bath!!
How would you treat chronic bronchitis?
- Bronchodilators - theophylline / terbutaline
- Anti-inflammatory - glucocorticoids (steroids)
- +/- Anti-tussives
What do bronchodilators do?
- Reduce spasm of lower airways
- Reduce intra-thoracic pressures
- Reduce tendency of larger airways to collapse
- Improve diaphragmatic function
- Improves muco-ciliary clearance
- Inhibit mast cell degranulation (reduced release of mediators of bronchoconstriction)
- Prevent microvascular leakage
What do glucocorticoids do?
- Broncho-dilatory
- Anti-inflammatory
- Inhibit both prostaglandin & leukotriene synthesis
- Potentiate beta-2 adrenergic activity
- Reduce leukocyte accumulation
- Induce lymphopenia & eosinopenia
- Reverse increased vascular permeability
- Alter macrophage function
- Inhibit fibroblast growth
- Modulate the immune system
What antibiotics could be used for respiratory infections?
- Potentiated amoxycillin
- Cephalexin
- TMP sulphonamides
- Fluoroquinoloes
- Doxycycline
- Clindamycin
- Metronidazole
What is Eosinophilic Lung Disease (ELD) aka Eosinophilic Bronchopneumopathy (EBP) aka Pulmonary Infiltrate with Eosinophils (PIE)
- Spectrum of disease from “chronic bronchitis” to pulmonary granulomatous disease
- Usually a mixture of bronchial and interstitial pulmonary involvement
- Usually young dogs, large breeds
- Presumed hypersensitivity to inhaled allergens (or parasites e.g. migrating Toxocara canis)
- > 25% eosinophils
What is Tx of EBP / PIE?
- Prednisolone - 2mg/kg/day
What is the most common cause of coughing in cats?
- Inflammatory airway disease / allergic airway disease
What is seen with feline asthma?
- Affected cats present with a cough
- Allergic airway disease
- Reactive bronchoconstriction may also result
- Can have air trapping and severe dyspnoea
- Expiratory dyspnoea (bronchoconstriction affects expiratory phase more than inspiratory)
- May auscultate expiratory wheezes
How would you treat a dyspnoeic cat with feline asthma?
- Minimise stress
- Provide humidified oxygen (in incubator; oxygen cage)
- Give IV steroids (e.g. dexamethasone 1 mg/kg)
- Bronchodilators e.g. Terbutaline (0.01 mg/kg IM or IV)
- Consider MDI admin. of bronchodilators (salbutamol)
- Severe, life-threatening distress: Adrenaline (0.1ml of 1:1000 IV or via ET tube)
How can you manage feline asthma using inhalers + management?
- Salbutamol - 1 puff as required - lasts 4 hrs
- Fluticasone - 2 puffs a day - takes 10-14days for peak effect
- Keep away from environmental allergens
- Bronchodilators - terbutaline
- Prednisolone
What is seen with bronchial foreign bodies?
- Sudden onset coughing
- Usually gun dog breeds (scenting / sniffing)
- History of exercise through fields / arable crops / woodland
- If long standing, halitosis often marked
- Partial response to antibiotics
What are other causes of coughing?
- Bronchial / Pulmonary neoplasia
- Lung parenchymal disease (typically ineffective cough
- Angiostrongylus vasorum infestation
- Cardiac disease in the dog – MVD, DCM
