Week 103 - COPD

Question 1

What is a definition of COPD?

Answer 1

Disease causing airflow obstruction that is not fully reversible.

Question 2

What is FEV1?

Answer 2

The volume of air that can be expired in one second and a full inspiration.

Question 3

What affect does COPD have on FEV1?

Answer 3

Reduced, obstructive lung disease.

Question 4

What are the three main pathphysiologies of COPD?

Answer 4

1) Chronic Bronchitis
2) Emphysema
3) Respiratory Failure

Question 5

What is Chronic Bronchitis?

Answer 5

Cough, production of purulent sputum for >3 months of at least 2 consecutive years.

Question 6

What is the pathogenesis of bronchitis?

Answer 6

• Inflammation and narrowing of bronchi.
• Increased mucous secretion (Due to hypertrophy of goblet cells)
• Squamous metaplasia, resulting in loss of cilia.

Question 7

What is emphysema?

Answer 7

Destruction of lung tissues distal to terminal bronchioles and loss of elasticity.

Question 8

What is the pathogenesis of emphysema?

Answer 8

• Inflammation occurs, inflammatory cells infiltrate epithelium.
• Proteases are released by the cells.
• Collagen/ elastin is broken down.
• This results in small bronchioles snapping shut, trapping air and resulting in hyperinflation.

Question 9

What deficiency can cause people to be more prone to developing emphysema?

Answer 9

• Alpha-1 Anti Trypsin.

* Alpha-1 Anti Trypsin is an anti-protease.

Question 10

What is respiratory failure?

Answer 10

Sufficiently impaired gas exchange that leads to hypoxaemia (<8.0 kPa O2 in arterial blood)

Question 11

What are the two types of respiratory failure?

Answer 11

1) Pink puffers

2) Blue bloaters

Question 12

What are pink puffers?

Answer 12

These are people with a low PaO2 and a normal PaCO2, they therefore need a high respiratory effort in order to maintain normal PaCO2.

Question 13

What are the symptoms/signs of a pink puffer?

Answer 13

• Dyspnoea
• Barrel Chest
• Accessory muscle use
• Paradoxical costal margin.
• Weight loss

Question 14

What are blue bloaters?

Answer 14

these are people with a low PaO2 and a high PaCO2, they can’t maintain enough respiratory effort to keep the PaCO2 down.

Question 15

What are the signs/symptoms of blue bloaters?

Answer 15

• Less breathless than pink puffers.
• Cyanosis and flapping tremor.
• Oedema and high JVP

Question 16

Why do blue bloaters have a high JVP and oedema?

Answer 16

Due to Cor Pulmonale (Right sided heart failure) as a result of pulmonary hypertension.

Question 17

Week 103 - COPD: To which level is cartilage present in the airways?

Answer 17

From trachea to proximal bronchioles.

Question 18

Week 103 - COPD: What three cells make up the bronchial epithelium?

Answer 18

• Goblet cells
• Ciliated columnar cells
• Bronchial gland

Question 19

Week 103 - COPD: What is the WHO definition of Chronic bronchitis?

Answer 19

• An inflammatory process in the wall of the bronchioles with excessive production of mucus and sputum from hypertrophic glands.
• The small airways are narrow.
• Morning cough for more than 3 months per year.

Question 20

Week 103 - COPD: What is the pathology behind chronic bronchitis?

Answer 20

• Cigarette smoke and other irritants lead to,

• Increased goblet cells, mucous glands and mucus in the lumen.
• Inflammatory cell infiltration.

Question 21

Week 103 - COPD: alpha-1-antitrypsin deficiency can lead to which lung pathology? What is the process behind it?

Answer 21

• Emphysema

• Smoke causes inflammatory cell infiltration.
• Cells release proteases.
• These over-whelm the bodies natural anti-proteases.
• Causing destruction of alveolar walls.

Question 22

Week 103 - COPD: What is emphysema?

Answer 22

Destruction of lung tissue distal to the terminal bronchioles. There is degenerative loss of radial traction of the bronchial walls.

Question 23

Week 103 - COPD: What distinguishes small airway disease from emphysema?

Answer 23

small airway disease has fibrosis.

Question 24

Week 103 - COPD: What is type 1 respiratory failure? How is is it typically caused?

Answer 24

• Hypoxemia without hypercapnia.

* It is typically caused by a V/Q mismatch.

Question 25

Week 103 - COPD: What is type 2 respiratory failure?

Answer 25

• Hypoxemia and hypercapnia.

* Due to inadequate alveolar ventilation.

Question 26

Week 103 - COPD: What occurs to spirometry results in obstructive lung disease?

Answer 26

• FEV1 reduced
• FVC normal/reduced
• FEV1/FVC = reduced (normal is around 80%)

Question 27

Week 103 - COPD: How does the FEV1 % predicted lead to staging of COPD? (NICE 2010)

Answer 27

• ≥80% - mild
• 50-79% - moderate
• 30 - 49% - severe
•

Question 28

Week 103 - COPD: What is the four stepped algorithm for inhaled drug management of COPD?

Answer 28

1) As required SABA.
2) As required SABA and tiotropium (long acting anticholinergic bronchodilator).
3) As required SABA, tiotropium and LABA.
4) Add ICS/LABA combined inhaler.

Question 29

Week 103 - COPD: Give an example of a mucolytic and explain why it is good for the management of COPD.

Answer 29

• Carbocisteine (Mucodyne)

* Reduces acute exacerbations, the need for antibiotics, fewer days of illness.

Question 30

Week 103 - COPD: What are the management steps for treating an acute exacerbation of COPD?

Answer 30

• Nebulised bronchodilators.
• Controlled oxygen therapy.
• Antibiotics if sputum purulent.
• IV fluids
• Corticosteroids
• Consider IV aminophylline
• Chest physio
• Non-invasive ventilation
• ITU if appropriate (Ceiling of treatment)

Question 31

Week 103 - COPD: What are the two receptors responsible for smooth muscle contraction/dilatation of the bronchioles?

Answer 31

• M receptor - Broncho-constriction

* B2 receptor - Broncho-Dilatation

Question 32

Week 103 - COPD: Give some examples of B2-agonists.

Answer 32

• SABA - Salbutamol, Terbutaline

* LABA - Salmeterol, Formoterol

Question 33

Week 103 - COPD: What are the side effects of B2-agonists?

Answer 33

Tremor, Hypokalaemia, tachycardia.

Question 34

Week 103 - COPD: How do muscarinic antagonists work? Give examples.

Answer 34

• Antagonises the effect of acetylcholine on the muscarinic receptors to reduce bronchoconstriction.
• Ipratropium and Tiotropium