Acute Respiratory Distress Syndrome

Question 1

Define Acute Respiratory Distress Syndrome:

Answer 1

Syndrome of acute and persistent Lung Inflammation with increased vascular permeability

Question 2

Explain the aetiology of Acute Respiratory Distress Syndrome:

Answer 2

Severe insult to the lungs and other organs results in the release of inflammatory mediators.

These lead to increased capillary permeability

Leads to Pulmonary Oedema

Results in impaired gas exchange and reduced lung compliance

Question 3

List 9 causes of Acute Respiratory Distress Syndrome​:

Answer 3

• COVID-19
• Sepsis
• Aspiration
• Pneumonia
• Pancreatitis
• Trauma/burns
• Transfusion
• Transplantation (marrow and lung)
• Drug overdose/reaction

Question 4

Describe the onset and three stages of Acute Respiratory Distress Syndrome:

Answer 4

Acute onset obvs

Exudative ⇒ Proliferative ⇒ Fibrotic

Question 5

What is the annual incidence of Acute Respiratory Distress Syndrome?

(before COVID)

Answer 5

UK: 1:6000

1-15% of ITU admissions ARDS present

Question 6

What are the presenting symptoms of Acute Respiratory Distress Syndrome:

Answer 6

Rapid deterioration of resp function

Dyspnoea

Cough

Symptoms of Cause

Question 7

What are the signs of Acute Respiratory Distress Syndrome o/e?

Answer 7

Cyanosis
Tachypnoea
Tachycardia

Widespread Inspiratory Crackles
Hypoxia refractory to O₂ treatment

(can be asymmetric in early stages)

Question 8

What would you see on a CXR of a pt with Acute Respiratory Distress Syndrome?

Answer 8

Bilateral alveolar infiltrates and interstitial shadowing

Question 9

What investigations would you perform in someone who presents with Acute Respiratory Distress Syndrome?

Answer 9

CXR

Bloods - to figure out cause

Echo - valvular dysfunction, heart failure

Pulmonary Artery Catheterisation - check pulmonary capillary wedge pressure

Bronchoscopy - aspiration, micro and cyto samples