Clinical Features of COPD Flashcards
What is the definition of COPD?
Chronic obstruction of lung airflow that interferes with normal breathing and is not fully reversible
Slowly progressive disorder
Airflow obstruction doesn’t change much over several months
Why does obstruction of the airways occur?
Small-airway narrowing - worsened by inflammation and mucus
Leads to progressive breathlessness on exertion, coughing, wheezing
What causes luminal occlusion?
Secretion of mucus and inflammatory exudate
Thickening of airway wall
What happens to the airway wall?
Thickens
What is ACOS
Asthma, COPD, overlap syndrome
Symptoms of Asthma and COPD
What happens to elasticity and alveolar attachments?
Loss of elasticity and disrupted alveolar attachments
What causes COPD (apart from smoking?)
Passive smoking
Maternal smoking (Reduces FEV1 and increases respiratory illness)
Air pollution
Occupation (jobs exposing to dusts, vapours, fumes)
What are the examinations for COPD?
No diagnostic tests
May be normal in early stages
Reduced chest expansion
Prolonged expiration/Wheeze
Hyperinflated chest
Respiratory failure
What is the effect of alpha 1 antitrypsin ?
Limits damage caused by activated neutrophils releasing elastase in response to infection/cigarette smoke
Deficiency leads to breakdown on self lung tissue
What percentage of smokers develop clinically significant COPD?
20%
What is a normal pack year?
Over 20
What is a pack year?
1 pack year = 1 pack a day for a year
What is the rate of decline of FEV1?
Non-smoker - 30 ml/yr
SMOKER - 50 ml/yr
What is your typical COPD patient?
- Typical symptoms
- >35 years
- Smoking or occupational exposure
- Absence of clinical features of asthma
What are the differential diagnosis for COPD?
COPD
Asthma
Lung cancer
Left ventricular failure
Fibrosing alveolitis
Bronchiectasis Rarities
TB
Recurrent pulmonary emboli