COPD

Question 1

What is the definition of COPD?

Answer 1

Progressive and irreversible (or partially reversible) airflow obstruction due to chronic bronchitis and emphysema

Question 2

What is the definition of chronic bronchitis?

Answer 2

Cough productive of sputum most days for 3 months during two consecutive years

Question 3

What is the definition of emphysema?

Answer 3

Abnormal and permanent enlargement of air spaces distal to the terminal bronchioles associated with destruction of their walls without obvious fibrosis

Question 4

What are the clinical signs of COPD?

Answer 4

1. Tar/nicotine staining
2. CO2 retention flap, bounding pulse, or even papilloedema
3. Purse lip breathing (self produced PEEP to keep airway open)
4. Central trachea with reduced cricoid-notch distance (< 3cm), trachea tug
5. Accessory muscle use for respiration
6. Hyper- expanded chest, indrawn lower intercostal muscle on inspiration
7. Resonant percussion with loss of cardiac and hepatic dullness
8. Expiratory polyphonic wheeze
9. Reduced breath sound, with prolonged expiratory phase
10. Cor pulmonale (lung issue causing right heart failure)
11. Chronic steroid use - cushingoid, steroid purpura, proximal myopathy

Complete physical examination with:
12. Sputum mug
13. Bedside spirometry - forced expiratory time (FET > 6s)

Relevant negatives:
14. No clubbing - clubbing indicates possible malignancy

Question 5

What are the causes of COPD?

Answer 5

Smoking
Industrial dust exposure
Alpha 1 antitrypsin deficiency

Question 6

How would you investigate a patient with COPD?

Answer 6

CXR - hyperexpanded, pneumothorax
ABG - type 2 respiratory failure
Bloods - look for infection, alpha 1 antitrypsin
Spirometry - low FEV1, FEV1/FVC <0.7
Reduced gas transfer factor

Question 7

What is the treatment of COPD?

Answer 7

Smoking cessation is single most beneficial intervention
Long term oxygen therapy
Pulmonary rehabilitation
Beta agonists
Tiotropium
Inhaled corticosteroids
Vaccinations

Question 8

What are the inclusion criteria for long term oxygen therapy?

Answer 8

Non smoker
PaO2 <7.3 on air (<8 if cor pulmonale)
PaCO2 that does not rise excessively on oxygen
Improves average survival by 9 months

Question 9

What are the differential diagnoses of a wheezy chest?

Answer 9

COPD
Granulomatous polyangitis
Obliterative bronchiolotis
Rheumatoid arthritis

Question 10

What is the pathophysiology of COPD?

Answer 10

1. Insults activate neutrophils and macrophages to release elastases and overcome anti-proteases activity.
   -> lung destruction from elastase damage
2. Insults cause oxidative stress and free radial formation
   -> apoptosis and necrosis