Week 2 - COPD

Question 1

What are the main causes of COPD?

Answer 1

Smoking, but also dust, occupational factors, pollutants

Question 2

What other factors are associated with COPD?

Answer 2

Age, females, lower socioeconomic status, recurring childhood infection, small lung size

Question 3

Why does smoking cause COPD?

Answer 3

Chemicals in smoke release elastase which breaks down elastin in alveolar tissue so less elastic tissue to push air out of lungs

Question 4

What deficiency can lead to emphysema and how?

Answer 4

Alpha 1 antitrypsin. Antitrypsin fixes imbalance between protease-antiprotease, otherwise known as elastase-antielastase. If you have a deficiency, the balance remains and elastase will break down elastic tissue. Smoking + this is disastrous

Question 5

What are the symptoms of COPD? (5)

Answer 5

Cough, sputum, wheezing, breathlessness, frequent chest infections

Question 6

What should you expect upon examination of a COPD exacerbation patient?

Answer 6

Cyanosis, breathless, wheeze, pursed lip breathing, chest wall deformities/hyperinflation, raised JVP, cachexia, or peripheral oedema

Question 7

What is cachexia?

Answer 7

Wasting of the body muscle and fat due to chronic disease. May be able to see ribs easily through skin

Question 8

What are some of the less common symptoms of COPD?

Answer 8

Weight loss, fatigue, swollen ankles (peripheral oedema)

Question 9

Why does weight loss occur in COPD?

Answer 9

Increased metabolic activity. Cachexia. Often seen in cancer

Question 10

What chest wall deformity may be seen in COPD?

Answer 10

Barrel chest - looks like barrel is inside as its hyper-inflated, so anterior posterior distance is greater than expected

Question 11

What is the mMRC dyspnoea scale?

Answer 11

Modified medical research council. From 0-4, stages to represent how breathless a patient is. 0 is only breathless upon strenuous exercise. 4 is breathless when dressing or too breathless to leave the house

Question 12

What is the criteria for COPD diagnosis? (4)

Answer 12

When patient meets criteria - over 35, has risk factor of smoking/occupational, absence of asthma features and confirmed airflow obstruction after b2 agonist using spirometry

Question 13

What are the 4 stages of COPD?

Answer 13

Mild - FEV1 80%
Moderate - FEV1 50-79%
Severe - FEV1 30-49%
Very severe - FEV1 <30%

Question 14

What is the purpose of a chest X-ray in diagnosis of COPD?

Answer 14

Eliminated alternative pathology, like tumour or oedema that may be causing same symptoms

Question 15

What test can differentiate between asthma and COPD and (maybe) confirm COPD diagnosis?

Answer 15

CO gas transfer test. Should decrease in COPD as less gas exchange and transfer is occurring

Question 16

What is a high res CT scan used for?

Answer 16

Can see alveoli size in emphysema to determine if a patient has it and which type

Question 17

What are the 4 types of emphysema?

Answer 17

Centriacinar, panacinar, periacinar and bullous emphysema

Question 18

How does an acute exacerbation present?

Answer 18

Usually to a GP with change in cough or sputum, and general worsening symptoms

Question 19

What can cause an acute exacerbation?

Answer 19

Infection, change in medication, pneumothorax, blood clots, change in air quality

Question 20

What are features of severe COPD?

Answer 20

Spirometry, history of exacerbations, presence of co-morbidity like heart disease, cor pulmonae or secondary polycythaemia

Question 21

What is the difference between type 1 and type 2 respiratory failure?

Answer 21

Type 1 - individual is hypoxic only. Reduced pO2 in arterial blood

Type 2 - individual has reduced pO2 and increased pCO2 as difficult to exhale. Seen in very severe COPD

Question 22

When do we see flapping tremor and what is it caused by?

Answer 22

In type 2 respiratory failure due to increased pCO2 - hypercapnia. Acidosis in the blood causes central chemoreceptors to be desensitised to changes in H+ and thus pH, so ventilators drive must come from peripheral chemoreceptors.

Question 23

What causes cor pulmonale?

Answer 23

Thickening of muscle on right side of heart and increased pressure on left of heart, due to abnormalities of the lung or pulmonary vessels

Question 24

What is secondary polycythaemia? What can it lead to?

Answer 24

Increase haemoglobin level due to body tissues detecting hypoxia and releasing erythropoietin, causing more RBC’s to be formed. This causes increased haematocrit and blood viscosity

Can lead to strokes and many vascular issues due to viscosity and haematocrit

Question 25

What happens as COPD progresses?

Answer 25

It’s progressive and terminal, so at end stage you’ll see a rapid decline with many exacerbations and worsening symptoms. Lung function reclines and then is slightly regained after exacerbations, until death