12. Pathology of Obstructive Lung Disease

Question 1

What are some obstructive airway diseases?

Answer 1

Chronic Bronchitis
Emphysema
Asthma

Question 2

What do these three obstructive airways diseases have in common and what differs?

Answer 2

All caused by airway obstruction but the mechanism for the the obstruction is different

Question 3

What is Chronic Bronchitis and Emphysema better known as?

Answer 3

Chronic Obstructive Pulmonary Disease

COPD

Question 4

What is FEV1?

Answer 4

The Forced Expiratory Volume of air exiting the lung in the first second of this exercise

Question 5

What is FVC?

Answer 5

The Final Total amount expired

Question 6

What percentage of FVC is usually FEV1?

Answer 6

70-80%

Question 7

What are the statistics for normal FEV1, FVC and FEV1:FVC?

Answer 7

FEV1 is about 3.5 – 4 litres
FVC is about 5 litres
FEV1 : FVC is 0.7 – 0.8

Question 8

What is the predicted FVC based on?

Answer 8

Age
Sex
Height

Question 9

How can COPD be measured accurately?

Answer 9

Spirometry

Question 10

How may obstructive lung disease also be demonstrated?

Answer 10

Peak Expiratory Flow Rate

PEFR

Question 11

What is the normal PEFR?

Answer 11

400-600 l/min

Question 12

What is the normal range of best value for PEFR?

Answer 12

80-100%

Question 13

What is the moderate fall of best value for PEFR?

Answer 13

50-80%

Question 14

What is the marked fall of best value for PEFR?

Answer 14

<50%

Question 15

What happens in Obstructive Lung Disease?

Answer 15

There is AIRFLOW LIMITATION
Peak Expiratory Flow Rate (PEFR) is reduced
FEV1 is REDUCED
FVC may be reduced
FEV1 is less than 70% of FVC

Question 16

What is Bronchial Asthma considered to be?

Answer 16

Considered to be REVERSIBLE airways obstruction either spontaneously or as a result of medical intervention

Question 17

What is Bronchial Asthma considered to be?

Answer 17

Considered to be REVERSIBLE airways obstruction either spontaneously or as a result of medical intervention

Question 18

How can bronchial smooth muscle contraction and inflammation be modified?

Answer 18

By drugs

Question 19

What is the aetiology for Chronic Bronchitis and Emphysema?

Answer 19

SMOKING
Atmospheric Pollution
Occupation
Effect of age and susceptibility

Question 20

What is an extremely rare cause of emphysema?

Answer 20

Alpha-1-antiprotease (antitrypsin) deficiency

Question 21

What is the prevalence of chronic bronchitis and emphysema?

Answer 21

Men > Women but increasing in developing countries

Question 22

What is is Chronic Bronchitis clinically defined as?

Answer 22

Cough productive of sputum most days in at least 3 consecutive months for 2 or more consecutive years

(This excludes TB, bronchiectasis etc Clinically may be confused with Chronic bronchial asthma)

Question 23

What are the morphological changes of large airways in Chronic Bronchitis?

Answer 23

Mucous gland hyperplasia
Goblet cell hyperplasia
Inflammation and fibrosis is a minor component

Question 24

What are the morphological changes of small airways in Chronic Bronchitis?

Answer 24

Goblet cells appear

Inflammation and fibrosis in long standing disease

Question 25

What is the pathological definition of emphysema?

Answer 25

Increase beyond the normal in the size of airspaces distal to the terminal bronchiole arising either from *dilatation* or from DESTRUCTION OF THEIR WALLS and *without obvious fibrosis*.

Question 26

What are forms of emphysema?

Answer 26

Centriacinar Panacinar Periacinar Scar 'irregular' 'bullous emphysema'

Question 27

What happens in centre-acinar emphysema?

Answer 27

Begins with bronchiolar dilatation | Then alveolar tissue is lost

Question 28

What is the difference between pan-acinar and centri-acinar?

Answer 28

``` Pan-acinar = By area Centri-acinar = By number ```

Question 29

What is a Bulla or bleb?

Answer 29

An emphysematous space greater than 1cm Bleb is often used to describe such spaces just underneath the pleura

Question 30

What is pathogenesis of emphysema?

Answer 30

Smoking - Protease - antiprotease imbalance Ageing Alpha-1-antitrypsin deficiency

Question 31

What equilibrium occurs in a normal individual?

Answer 31

Anti-elastase (anti-proteases) Elastase (proteases)

Question 32

What are neutrophils and macrophages transformed into?

Answer 32

Elastase (proteases)

Question 33

Repair mechanisms, elastase and elastin synthesis form ________

Answer 33

Elastin framework in alveolar tissue

Question 34

What is absent in Alpha 1 antitrypsin deficiency?

Answer 34

Anti-elastase (anti-proteases)

Question 35

What happens for emphysema to occur?

Answer 35

Elastin framework in alveolar tissue is not produced, only tissue destruction

Question 36

What happens for emphysema to occur?

Answer 36

Elastin framework in alveolar tissue is not produced, only tissue destruction

Question 37

What is reduced due to smoking?

Answer 37

Anti-elastase (anti-proteases) Repair Mechanisms Elastin Synthesis

Question 38

What is increased due to smoking?

Answer 38

Neutrophils Macrophages Elastase (proteases)

Question 39

What is traditionally believed about airway obstruction in COPD?

Answer 39

Irreversible but there may be a reversible component

Question 40

What is the small airways of a person with COPD reacts to pharmological intervention?

Answer 40

Smooth muscle tone | Inflammation

Question 41

In emphysema what is most important?

Answer 41

Loss of alveolar attachments