Clinical Case Studies - COPD

Question 1

• What is COPD?

Answer 1

A Chronic obstructive airway disease that is characterised by its irreversibility.

Made up of:

• Chronic bronchitis - cough with sputum production for at least three months in 2 consecutive years
• Emphysema - permanently dilated airways distal to the terminal bronchioles with alveolar destruction and bullae formation. Defined histologically

Question 2

What are the causes of COPD?

Answer 2

GASES

• Genetics - alpha-1 antitrypsin deficiency (results in loss of protection against proteases)
• Air pollution
• Smoking
• Exposure through occupation eg coal mining
• Secondhand smoke exposure

Question 3

What is the pathophysiology of chronic bronchitis?

Answer 3

• Chronic infection
• Chronic infiltration of the respiratory submucosa by inflammatory cells
• Mucus gland hyperplasia
• Smooth muscle hypertrophy
• Bronchial lumen narrowing
• (blue bloaters)

Question 4

What is the pathophysiology of Emphysema?

Answer 4

• Alveolar walls are destroyed
• Bullae formation
• Fusion of adjacent alveoli
• Reduced surface area for gas exchange
• Decreased elastic recoil
• Air trapping
• (pink puffers)

Question 5

How would you investigate COPD?

Answer 5

• Spirometry - FEV1 <80% predicted, FEV1/FVC <0.7
• CXR - hyperinflation/emphysematous change/diaphragmatic flattening
• Bloods
• ECG - Cor Pulmonale
• Sputum Culture

Question 6

How does pursed lip breathing help?

Answer 6

Pursed-lip breathing increases positive pressure generated in the conducting branches of the lungs. This can hold open bronchioles in patients with high lung compliance, such as those with emphysema