Restrictive Lung Disease

Question 1

What is a broad definition of RLD?

Does this affect inspiration or expiration?

Answer 1

A reduction in lung volume

Makes it hard to inspire

Question 2

What are the 2 broad categories of RLD?

What does each mean?

Answer 2

Intrinsic = problem is with the lug

Extrinsic = affects the lung indirectly

Question 3

Give some examples of other structures affected in extrinsic RLD?

Answer 3

• pleura
• chest wall
• neuromusculature

Question 4

What is the name of the graph that details forced expiration?

What are it’s axes?

Answer 4

Forced expiration Spirograph

X = time
Y = litres

Question 5

What is FEV1?

What is FVC?

What is the normal ratio and what is the name of this?

Answer 5

FEV1 = maximal forced expiratory volume in 1 second following maximal inspiration

FVC = maximal forced expiratory volume following maximal inspiration

Ratio = “Forced Expiratory Ratio” = usually 75% in health

Question 6

What is seen in RLD in respect to the:

1) FEV1
2) FVC
3) FEV1/FVC

Answer 6

1) reduced FEV1 due to not breathing as much in (therefore can not breathe as much out!)
2) reduced FVC (for the same reason)
3) as BOTH reduced the RATIO remains the same or even INCREASES!!

Question 7

Is gas transfer reduced in RLD?

Answer 7

Depends on the cause…

…if the cause is EXTRINSIC and lung parenchyma disease based then yes, if not then no

Question 8

Give some examples of RLD.

Answer 8

Lung fibrosis

Respiratory muscle weakness

Question 9

What happens in intrinsic RLD?

Answer 9

The lung elastic recoil is INCREASED, making it harder to expand

This results in hypoxia due to a V/Q mismatch (V vein reduced)

Question 10

What happens in extrinsic RLD?

Answer 10

The compliance of the respiratory system is decreases meaning hypoxia occurs again due to a V/Q mismatch (with V reducing) but this time there are areas of atelectasis

Question 11

What is atelectasis?

Answer 11

Lung collapse

Question 12

What is diffuse pleural thickening?

What type of RLD is it?

What can cause it?

Answer 12

Thickening of the pleura?

It is EXTRINSIC as it is not affecting the lung directly

It can be caused by:

• Infection (TB)
• asbestosis

Question 13

What is chest wall disease?

What type of RLD is it?

What can cause it?

Answer 13

Chest wall disease is normally a deformation of the chest wall

It is extrinsic

It can be caused by:

• pectus excavatum
• kyphoscoliosis

Question 14

What is neuromuscular disease?

What type of RLD is it?

What can cause it?

Answer 14

It is basically a type of paralysis or the muscles and neurovasculature supplying respiration

It is extrinsic RLD

It can be caused by:

• polio
• motor neurone disease
• muscular dystrophy
• myasthenia gravis

Question 15

What is ILD?

Answer 15

Interstitial lung disease = blanket term for a RANGE of disorders that cause lung fibrosis (scarring/stiffening)

It includes pulmonary fibrosis

Question 16

Which areas of the lung are affected in ILD?

Answer 16

Distal to the terminal bronchioles (alveoli)

The areas between the aleveoli and the capillary endothelium (interstitium)

Question 17

What is gas transfer factor?

Answer 17

TLCO = transfer of the lungs CO (carbon monoxide)

Question 18

Name 3 drugs which can cause ILD?

Answer 18

Amiodarone (anti-arrhythmic)
Nitrofuratoin (bladder infection antibiotic)
Bleomycin (chemotherapy)

Question 19

What 3 respiratory conditions is clubbing and crackles seen in?

What type of lung disease is each?

Answer 19

Idiopathic pulmonary fibrosis (finer crackles) = ILD (restrictive)

Bronchiectasis (courser crackles) = widened airways and excess mucous = obstructive lung disease

Cystic fibrosis (course crackles) = obstructive lung disease

Question 20

What does TLCO tell you about a lung condition?

Answer 20

If the problem is intrinsic or extrinsic to the lungs

If TLCO reduces = INTRINSIC problem (with lungs)
If TLCO NOT reduces = EXTRINSIC problem (not lungs e.g. chest wall deformity)

Question 21

What is another name for idiopathic pulmonary fibrosis, which is also its pathology?

Answer 21

Usual interstitial pneumonia

Question 22

Who are the group most at risk of IPF?

Answer 22

Males aged 66+

Question 23

What test is key in ILD?

Why is this?

Answer 23

CT scan

Diagnosis is by this method +/- biopsy

Question 24

What tests are used in ILD to identify the:

1) severity
2) prognosis

Answer 24

1) severity = lung function tests (VC, TLCO)

2) prognosis = exercise tests

Question 25

What does ILD treatment aim to do?

Answer 25

Halt progression, there is no cure

Question 26

Name 2 drugs used to rest IPF and explain how they work.

Answer 26

1) pirfenidone = anti-fibrotic

2) nintedanib = anti-fibrotic

Question 27

Who is most at risk of sarcoidosis?

What level is raised in their serum?

Answer 27

Black/Scandinavians

Serum ACE (enzyme)