Management of COPD

Question 1

What causes COPD & which part of the lungs is mainly effected?

Answer 1

It is caused by exposure to noxious gases/particles.

It mainly affects the peripheral airways & lung parenchyma.

Question 2

What part of the respiratory tract is more prone to colonisation of bacteria in COPD patients?

Answer 2

The lower respiratory tract (LRT).

Question 3

CD8 lymphocytes, neutrophils, oxidants & proteases can lead to what 3 things in COPD?

Answer 3

1. Increased mucus
2. Abnormal tissue repair
3. Alveolar wall destruction

Question 4

What are the symptoms of COPD?

Answer 4

1. Chronic cough
2. Breathlessness
3. Arterial hypoxemia
4. Pulmonary hypertension
5. Systemic effects

Question 5

What is the FEV1/FVC ratio of a COPD patient using a spirometer?

Answer 5

FEV1/FVC <0.7

Question 6

What does the mMRC dyspnoea scale measure?

Answer 6

It is a questionnare used to measure breathlessness in patients.
Ranges from grade I (normal) - grade V(severe)

Question 7

What are some non-pharmacological treatments of COPD?

Answer 7

1. Smoking cessation
2. Vaccinations
3. Pulmonary rehabilitation

Question 8

What are some examples of B2 agonists and what is their duration of action?

Answer 8

SABA: salbutamol, terbutaline
- 3-5h duration

LABA: salmeterol, formoterol
- 8-12h duration

Ultra LABA: vilanterol, indacaterol
- 24h

Question 9

What are the side effects of using B2 agonists?

Answer 9

1. Tremor
2. Headaches
3. Tachycardia
4. Hypokalaemia

Question 10

What is the mechanism of action of B2 agonists?

Answer 10

1. B2 agonist binds & forms structural changes
2. Alpha subunit of receptor dissociates & allows cAMP levels to increase
3. cAMP binds to PKA, causing bronchodilation

Question 11

What can chronic use of B2 agonists lead to?

Answer 11

Desensitisation of the receptors & a higher tolerance in patients.
This can also decrease cAMP levels.

Question 12

What are some examples of musarinic agonists?

Answer 12

SAMA: ipratropium
- <15min onset

LAMA: tiotropium
- Selective for M3 receptors

Question 13

What is the mechanism of action of xanthines?

Answer 13

E.G. aminophylline, theophylline

• They decrease cytokines/apoptosis/neutrophils = reducing inflammation
• Bronchodilation is hence enhanced.

Question 14

How is theophylline given & how is it eliminated?

Answer 14

It is given IV, and it eliminated via CYP450.
It also has a narrow therapeutic index.
Side effects can include: vomiting, hypokalaemia, insomnia, nervousness.

Question 15

What is the mechanism of action of theophylline?

Answer 15

It inhibits phosphodiester enzymes, so CAMP levels are increased (+ cGMP)
This leads to bronchodilation & also antagonise adenosine receptors.
It can also cause seizures.

Question 16

What is the mechanism of action of oral phosphodiesterase 4 inhibitors (PDE4)?

Answer 16

E.G. Roflumilast

• They inhibit cAMP hydrolysis into AMP
• cAMP increases = bronchodilation

Question 17

Why arent ICS’s used in COPD patients?

Answer 17

They have a limited response in COPD patients.

It can also cause pneumonia for them.

Question 18

What do mucolytics do?

Answer 18

E.G. carbocisteine, acetylcysteine

- They loosen sputum making it easier to cough out

Question 19

What antibiotic can be used to optimise therapy for COPD & for those who are having acute exacerbations?

Answer 19

Azithromycin 250mg TDS for a week.

Question 20

What are the 3 types of oxygen therapies?

Answer 20

1. LTOT - long term O2 therapy
   - Used at home for chronic hypoxia
   - Patient would have O2 levels <92%
2. Ambulatory O2
   - Used for patients who are active
   - Portable O2 cylinders used
3. SBOT - short burst O2 therapy

Question 21

What can you do to manage exacerbations?

Answer 21

1. Increase the dose of their bronchodilator

2. Give antibiotic or oral corticosteroid, e.g. prednisolone 30mg (for symptom relief)

Question 22

What can be given during in hospital treatment?

Answer 22

1. IV aminophylline
2. Doxapram
3. Invasive ventilation