ARDS

Question 1

Which of the following clinical conditions is the most common cause of acute respiratory distress syndrome (ARDS)?

A) Trauma
B) Sepsis
C) Pancreatitis
D) Drug overdose

Answer 1

Sepsis (40-60%)

Question 2

Which of the following is a key feature of the exudative phase of ARDS?

A) Proliferation of type II pneumocytes
B) Increased pulmonary compliance
C) Loss of alveolar barrier leading to protein-rich edema
D) Extensive alveolar fibrosis

Answer 2

Loss of alveolar barrier leading to protein-rich edema

• Alveolar capillary endothelial cells and type I pneumocytes (alveolar epithelial cells) are injured, with consequent loss of the normally tight alveolar barrier to fluid and macromolecules
• The exudative phase encompasses the first 7 days of illness after exposure to a precipitating ARDS risk factor
  
  • presenting within 12–36h after the initial insult, symptoms can be delayed by 5–7 days

Question 3

What is the main physiological consequence of the fibrotic phase of ARDS?

A) Decreased pulmonary vascular resistance
B) Increased lung compliance
C) Progressive pulmonary hypertension and fibrosis
D) Complete resolution of lung injury

Answer 3

Progressive pulmonary hypertension and fibrosis

• While many patients with ARDS recover lung function 3–4 weeks after the initial pulmonary injury, some enter a fibrotic phase that may require long-term support on mechanical ventilators and/or supplemental oxygen.
• The alveolar edema and inflammatory exudates of earlier phases convert to extensive alveolar duct and interstitial fibrosis.

Question 4

What is the effect of maintaining low left atrial filling pressures in ARDS patients?

A) It increases pulmonary edema and worsens oxygenation
B) It helps minimize pulmonary edema and improve lung compliance
C) It leads to increased risk of sepsis
D) It improves ventilator synchrony

Answer 4

It helps minimize pulmonary edema and improve lung compliance

• Maintaining a low left atrial filling pressure minimizes pulmonary edema and prevents further decrements in arterial oxygenation and lung compliance; improves pulmonary mechanics; and shortens ICU stay and the duration of mechanical ventilation

Question 5

Which of the following interventions has been shown to reduce 28-day mortality in patients with severe ARDS (PaO2/FiO2 ratio <150 mm Hg)?

A) Neuromuscular blockade
B) High tidal volume ventilation
C) Prone positioning
D) Routine glucocorticoid use

Answer 5

Prone positioning

• 2013 trial demonstrated a significant reduction in 28-day mortality with prone positioning (32.8 to 16.0%) for patients with severe ARDS (Pao2/Fio2 <150 mm Hg).

Question 6

Which of the following is an example of an indirect lung injury commonly associated with Acute Respiratory Distress Syndrome (ARDS)?

A) Pneumonia
B) Aspiration of gastric contents
C) Sepsis
D) Toxic inhalation injury

Answer 6

Sepsis

Question 7

Which therapy is recommended with strong clinical evidence (Grade A) for ARDS treatment?

A) High-PEEP or “open lung”
B) Low tidal volume mechanical ventilation
C) Prone positioning
D) ECMO

Answer 7

Low tidal volume mechanical ventilation

Question 8

What is the recommended target SpO₂ range for oxygenation in the initial management of ARDS according to the algorithm?

A) 92–100%
B) 88–95%
C) 80–85%
D) ≥96%

Answer 8

88–95%

Question 9

In the initial management of ARDS, what is the recommended plateau pressure limit during volume/pressure-limited ventilation?

A) ≤20 cmH₂O
B) ≤25 cmH₂O
C) ≤30 cmH₂O
D) ≤35 cmH₂O

Answer 9

≤30 cmH₂O

Question 10

What is the minimum acceptable pH target to avoid acidosis in ARDS management?

A) 7.25
B) 7.30
C) 7.35
D) 7.40

Answer 10

7.30

Question 11

In the algorithm for ARDS management, which of the following is recommended to maintain mean arterial pressure (MAP)?

A) ≥55 mmHg
B) ≥60 mmHg
C) ≥65 mmHg
D) ≥70 mmHg

Answer 11

≥65 mmHg