COPD Flashcards
What is COPD?
A progressive disease characterised by reduced lung function that is not fully reversible and exacerbations
What is the pathogenesis of COPD?
Exposure to noxious particles causes activation of inflammatory cells
These infiltrate the walls of bronchi and bronchioles and release protases
Protases cause inflammation of the airways, alveolar wall destruction and mucociliary dysfunction
Inflammation causes fibrosis and thickening of alveolar walls
What are some inflammatory cells involved in the pathogenesis of COPD?
Macrophages
Neutrophils
Cytokines
Proteases
What are the two conditions that are components of COPD?
Emphysema
Chronic bronchitis
What is emphysema?
Irreversible alveolar wall destruction leading to impaired gas exchange
What is chronic bronchitis?
Mucus hypersecretion
Partially reversible
Causes chronic productive cough
How does smoking contribute to COPD?
By inactivating alpha-1 antitrypsin
What are the risk factors for COPD?
SMOKING Alpha-1 antitrypsin deficiency Toxic gases Occupational dusts (cadmium, coal) Low birthweight Childhood respiratory infections
What are the symptoms of COPD?
Daily cough
- Productive or unproductive
- Frequently morning cough but becomes constant as disease progresses
Progressive breathlessness
Wheeze
Cold that seems to ‘settle in the chest’
Frequent lower respiratory tract infections
What are the signs of COPD?
Reduced breath sounds
Wheeze
Accessory muscles of respiration are used
Barrel chest (broad deep chest suggesting hyperinflation)
Poor chest expansion
Hyper-resonance
Coarse crackles in exacerbations
What are the systemic effects of COPD?
Hypertension Osteoporosis Depression Weight loss Reduced muscle mass with general weakness
How does COPD progress?
- Progressive airflow obstruction
- Impaired alveolar gas exchange
- Respiratory failure - decrease in PaO2, increase in PaCO2
- Pulmonary hypertension
- Right ventricular hypertrophy or failure
- Death
How is COPD diagnosed?
Spirometry - FEV1/FVC <0.7
What investigations are done in exacerbation of COPD?
Careful history CT scan Echo ECG Sputum culture Pulse oximetry ABG in unwell patients with abnormal pulse oximetry CXR FBC
What will spirometry show in COPD?
FEV1:FVC ratio is reduced (<70%)
PERF is low
FVC decreased
What is the treatment plan for COPD?
Breathless without frequent exacerbations: LABA/LAMA
Eosinophils >300: LABA/LAMA/ICS
Frequent exacerbations: trial of LABA/LAMA/ICS
What general management should be done in COPD?
Smoking cessation Influenza and pneumococcal vaccination Pulmonary rehabilitation Oxygen Active lifestyle and exercise
What are the ‘asthmatic features or features suggesting steroid responsiveness’:
Any previous diagnosis of asthma or atopy
Higher blood eosinophil count
Substantial variation in FEV1 over time
Substantial diurnal variation in PEFR
What diseases are associated with COPD?
Ischaemic heart disease Hypertension Diabetes Heart failure Cancer