Week 8 - Obstructive/Restrictive Lung Disease Flashcards
What is COPD?
A progressive, disabling lung disease characterized by airflow limitation that is not fully reversible.
“Airway inflammation and airflow limitation that is not fully reversible”
COPD aetiology - cigarette smoking
Inhalation of smoke causes inflammation and affects neutrophils, protease inhibitors. It causes a steady decline in lung function
Consequences of airflow limitation
- Prolonged expiratory time
- Collapse of small airways
- Gas trapping
- Hyperinflation
- Reduced secretion clearance
What is hyperinflation?
A condition in COPD where abnormal air trapping leads to increased lung volumes, causing difficulty in breathing.
What are two advantages of hyperinflation?
- Distends airways and prevents them from collapsing so readily during expiration
- Reduces resistance and increases airflow
What are some disadvantages of hyperinflation?
- Restricts further volume expansion (eg. during exercise)
- Additional burden on respiratory muscles - increased elastic loading
- Flattened diaphragm - reduced force generating ability
What is emphysema?
A condition involving permanent enlargement of the airspaces distal to the terminal bronchiole, with destructive changes in the alveolar wall.
Damage of air sacs, which supply oxygen to the blood (so when damaged, less oxygen can enter the blood)
What is chronic bronchitis?
Cough productive sputum on most days for at least 3 months for at least 2 successive years
What is asthma?
Obstructive lung disease characterised by airway hyper responsiveness to various stimuli
What is the difference between obstructive and restrictive lung disease?
Restrictive: reduced lung expansion
Obstructive: reduced airflow
List some consequences of restrictive lung disease
- Reduced expansion
- Effect on lung volume
- Potential for alveolar collapse
- Increased WOB
- Reduced ability to clear secretions, secondary infection
- Reduced exercise capacity
