Restrictive Lung Disease

Question 1

What is Restrictuve Lung Disease?

What are the two main types?

Answer 1

Reduced lung volume.

Intrinsic:

• Lung parenchyma.

Extrinsic:

• Pleura,
  
  • Chest wall,
    
    • Shape, something on the chest wall? (obesity)
• Neuromuscular diseases (“respiratory pump”).
  
  • E.g. Motor neuron disease.

Question 2

What is Intrinsic RLD?

Answer 2

An internal abnormality.

• Usually leading to the stiffening, inflammation, and scarring of the lung tissues.

Characterised by “reduced lung volume”.

Increased elastic recoil of lung.

• Lung cannot open fully.

Hypoxia due to VQ mismatch.

Question 3

What is Extrinsic RLD?

Answer 3

An external abnormailty.

• The chest wall, pleura and respiratory muscles.
• Disorders of these structures will cause lung restriction and impair ventilatory function.

Characterised by “reduced lung volume”.

Decreased compliance of respiratory system.

Hypoxia due to VQ mismatch from areas of atelectasis.

Question 4

What are two groups of extrinsic RLD?

Answer 4

Neuromuscular diseases:

• e.g. Poliomyelitis.

Non-muscular diseases:

• e.g. kyphoscoliosis.

Question 5

What is Diffuse Pleural Thickening?

How can it be caused?

Answer 5

Extrinsic RLD in which extensive scarring thickens the pleura, which is the lining of the lungs.

• Prevents lung expansion.

Caused by infection:

• e.g. Asbestos.

Question 6

What is Kyphoscoliosis?

What are the primary and secondary forms?

Answer 6

Kyphoscoliosis is a thoracic cage deformity that causes extrapulmonary restriction of the lungs.

Gives rise to impairment of pulmonary functions.

• i.e. an Extrinsic RDL.

The condition may be primary (idiopathic) or secondary to neuromuscular disease.

Question 7

What is Interstitial Lung Disease (ILD)?

Answer 7

ILD is an umbrella term for a large group of disorders that cause fibrosis of the lungs.

Characterised by cellular and extracellular matrix deposition.

The scarring causes stiffness in the lungs which makes it difficult to breathe.

Some example of ILDs include: Idiopathic Pulmonary Fibrosis.

Question 8

Key features of ILD.

Answer 8

Interstitial inflammation leading to fibrosis.

Impaired gas exchange.

• Results in ventilation:perfusion mismatch.

Symptoms:

• SOB / cough.

Abnormal CXR (chest xray).

Abnormal lung function;

• (restrictive, reduced lung volumes and gas transfer factor).

Question 9

Symptoms of ILD.

Answer 9

Shortness of Breath (SOB).

Cough.

Wheezing.

Chest pain.

Weight loss.

Muscle aches (associated with CT disease)