Disorders of pulmonary vasculature

Question 1

What is the blood supply to the lungs?

Answer 1

Pulmonary arteries that bring deoxygenated blood from the RV to be oxygenated

Bronchial arteries that bring oxygenated blood from the descending thoracic aorta to supply the lung tissue with oxygenated blood

Question 2

What is the difference between pulmonary and bronchial arteries?

Answer 2

Pulmonary: deoxygenated blood, relatively large diameter

Bronchial: oxygenated, small diameter

Question 3

Name 3 disorders of the pulmonary vasculature.

Answer 3

Pulmonary embolism
Pulmonary hypertension
Pulmonary vasculitis

Question 4

What is a pulmonary embolism?

Answer 4

An embolus that has broken off from a thrombus elsewhere in the body, that gets trapped in a blood vessel in the lungs

Causing parts of the lung to be starved of blood, and therefore oxygen

Question 5

What happens in a peripheral pulmonary embolism?

Answer 5

A minor PE

Infarction of the lung tissue that is starved of blood

Question 6

What happens in a central pulmonary embolism?

Answer 6

A major PE

Ischaemia in the whole lung

Question 7

What are the clinical features of a minor pulmonary embolism?

Answer 7

Pleuritic pain: sharp stabbing pain on inhalation

Question 8

What are the clinical features of a major pulmonary embolism?

Answer 8

Shock
Central chest pain
Hypoxia
Immediate mortality (usually)

Question 9

What is the differential diagnosis of pleuritic pain?

Answer 9

Pulmonary embolism

Infection

Musculoskeletal

Pneumothorax

Heart failure

Question 10

What type of pain is pleuritic pain?

Answer 10

Sharp stabbing

That worsens on inhalation of coughing

Question 11

What is Virchow’s triad?

Answer 11

3 factors that contribute to thrombosis:

1. Circulatory stasis
2. Endothelial injury
3. Hypercoagulability

Question 12

What is the blood pressure in the pulmonary circulation in comparison to systemic circulation?

Answer 12

1/6th of the pressure of systemic

Question 13

What is the blood volume in the pulmonary circulation in comparison to systemic circulation?

Answer 13

The same

Question 14

What happens if blood pressure in the lungs increases?

Answer 14

Strain on the right side of the heart, since it’s not built to withstand high pressures

Question 15

How do you define pulmonary hypertension?

Values

Answer 15

High blood pressure in the pulmonary circulation

Higher than 25mmHg at rest

Question 16

What is the usual pulmonary blood pressure at rest?

Answer 16

10-14mmHg

Question 17

What causes pulmonary hypertension?

Answer 17

Pulmonary artery hypertension:

• idiopathic
• hereditary
• SLE, RA
• drugs
• HIV
• Congenital heart disease

Secondary to:

• left heart disease
• lung disease
• hypoxia
• thromboembolic occlusion

Question 18

How do patients with pulmonary hypertension present?

Answer 18

Dyspnoea
Lethargy/fatigue
Ankle swelling
Chest pain
Synope

Question 19

Investigations for pulmonary hypertension?

Answer 19

CXR: shows enlarged pulmonary arteries, cardiomegaly

ECG: RV hypertrophy

ECHO: RV dilatation/hypertrophy

Question 20

Management of pulmonary hypertension?

Answer 20

Oxygen

Warfarin: due to increased risk of clotting with high BP

Diuretics for the oedema

Calcium channel blockers for pulmonary vasodilation

Treat underlying cause

Question 21

What is pulmonary vasculitis?

Answer 21

Inflammation of vessel walls
In the lungs

Umbrella term for a number of conditions

Question 22

What causes pulmonary vasculitis?

Answer 22

Anything that could inflame the blood vessels in the lung

Auto-immune + auto-inflammatory conditions

Granulomatous diseases

Question 23

What occurs as a result of the inflammation of the blood vessels in pulmonary vasculitis?

Answer 23

Inflammation leads to thickening a fibrosis of vessel walls