COPD (+emphysema)

Question 1

Define COPD

Answer 1

A preventable and treatable condition characterised by airflow limitation which is not fully reversible, and encompasses both emphysema and chronic bronchitis

Question 2

Epidemiological features of COPD

Answer 2

> 90% cases due to cigarette smoking
Development of COPD directly proportional to amount of cigarettes smoked per day
More common in older people
M:F = 1:1
5th leading cause of death and disability worldwide

Question 3

What is emphysema?

Answer 3

Abnormal, permanent enlargement of air spaces, due to alveolar weakening and rupture, distal to the terminal bronchiole, accompanied by destruction of the walls and capillary beds

Question 4

What happens to the values of pCO2, pO2 and RR in Va/Q mismatch?

Answer 4

pCO2 - Same or low
pO2 - Decreased
RR - Increased

Question 5

What causes the ‘Blue Bloater’ presentation in COPD?

Answer 5

Px fails to maintain respiratory effort
pCO2 increases
Insensitivity occurs
Px relies on hypoxic drive
Causes renal hypoxia
Fluid retention

Question 6

Why is oxygen therapy sometimes dangerous in COPD

Answer 6

Blue bloaters rely on hypoxic drive so oxygenating them removes the hypoxaemia

Question 7

Characteristic symptoms of COPD

Answer 7

Productive cough
Wheeze
Breathlessness
Increase SOB on exertion
Increases SOB in cold weather

Question 8

Signs observed in COPD

Answer 8

Mild COPD may have no signs but a wheeze

Severe COPD:
Tachypnoea
Use of accessory muscles
Hyperinflation
Pursing of lips on expiration
Reduced chest expansion
Resonant/Hyper-resonant percussion

Question 9

Pink puffer points

Answer 9

Increase in alveolar ventilation
Normal pO2
Normal or low pCO2
Breathless but not cyanosed
CO2 sensitive

Question 10

Blue bloater points

Answer 10

Decreased alveolar ventilation
Decrease pO2
Increase PCO2
Cyanosed but not breathless
CO2 insensitive

Question 11

Classification of Respiratory Failure

Answer 11

Type 1: Hypoxaemic

Type 2: hypercapnic

Question 12

O2/CO2 results in hypoxaemic resp. failure

Answer 12

pO2 <8

pCO2 - normal or low

Question 13

O2/CO2 results in hypercapnic resp. failure

Answer 13

pCO2 > 6

pO2 < 8

Question 14

Which two conditions encompass COPD?

Answer 14

Emphysema

Chronic obstructive bronchitis

Question 15

What is chronic bronchitis?

Answer 15

Chronic productive cough of more than 3 months duration for more than 2 consecutive years, with airflow limitation

Question 16

Causes of chronic bronchitis

Answer 16

Chronic irritation from smoking and recurrent infections

Question 17

2 causes of emphysema

Answer 17

1. Increased elastase production - more related to smoking

2. Inherited deficiency of a1 proteinase inhibitor - accounts for 1% of cases

Question 18

What breath sounds are heard in a patient with COPD

Answer 18

A wheeze may be heard
Crepitations if there is an infection
Prolonged expiratory time in chronic bronchitis

Question 19

What is the FEV1:FVC required for a diagnosis of COPD?

Answer 19

<70%

Question 20

Which 2 lung function tests could you do to aid diagnosis?

Answer 20

FEV:FVC

PEFR

Question 21

What may be seen on the CXR of a COPD patient?

Answer 21

Can often be normal

May observe overinflation w/ low flattened diaphragm

Question 22

What is the requirement for ‘overinflated lungs?’

Answer 22

> 6 ribs seen above diaphragm

Question 23

What would the FBC findings be?

Answer 23

Increased Hb
Increased PCV

Both due to persistent hypoxaemia

Question 24

What is cor pulmonale?

Answer 24

Right ventricular failure due to fluid overload secondary to lung disease. Characterised by pulmonary HTN + RV hypertrophy

Question 25

What is the usual A/VBG result seen in COPD?

Answer 25

Often normal

More advanced conditions may show a hypoxemic picture

Question 26

Advanced cases of COPD may show which characteristic feature on an ECG?

Answer 26

Tall P waves

Question 27

What are the treatment options for COPD?

Answer 27

General: Lifestyle changes + a SABA (salbutamol) or Antimuscuranic (ipratropium)

Mild/Moderate: Inhaled long acting antimuscuranic (tiotropium) + SABA (salbutamol)

Severe: Combination of LABA (salmeterol or formoterol) + corticosteroid (symbicort)

Remain symptomatic: Long acting antimuscuranic (tiotropium) + inhaled steroid + laba + refer

Question 28

Important complications of COPD

Answer 28

Nocturnal hypoxia
acute respiratory failure 
polycythemia
pneumothorax
cor pulmonate
lung carcinoma
acute exacerbations w/wo infection

Question 29

Aetiology of COPD

Answer 29

Smoking causes an inflammatory response, cilia dysfunction and oxidative injury

Oxidative stress + imbalance in proteinases and antiproteinases

Question 30

Pathophysiology of COPD

Answer 30

Chronic inflammation that affects central and peripheral airways, lung parenchyma and pulmonary vasculature

Narrowing and remodelling of airways + increased number of goblet cells + changes to vascular bed = hypertension

Question 31

Stages 1 to 4 of COPD all share a similar FEV1/FVC value which is

Answer 31

<70%

Question 32

Which vaccines should patients with cardiopulmonary disease be offered?

Answer 32

Viral influenza

S. Pneumonia

Question 33

5 Step Management of acute exacerbation of COPD

Answer 33

1. Oxygen
2. SABA + anticholinergic
3. Glucocorticoids
4. Abx
5. Mechanical ventilatory support (if above doesn’t work)

Question 34

Tests to order in COPD

Answer 34

ECG
Spirometry
Peak Flow
ABG
Bloods (check for infection)
Plus SATS