ALI v ARDS
Early v Late
Ventilation & PEEP
complications
Priority concepts
100

A patient with sepsis develops tachypnea and anxiety. ABG shows PaO₂ 72, PaCO₂ 30, pH 7.48. Oxygen improves saturation.

What is most likely occurring?

A. ARDS
B. Acute lung injury
C. Respiratory failure
D. Metabolic acidosis


Answer: B
Rationale: Early ALI = mild hypoxemia + respiratory alkalosis with compensation. Oxygen still helps.

100

A patient is in early ARDS. Which findings are expected?

A. Tachypnea
B. Respiratory alkalosis
C. Cyanosis
D. Anxiety
E. Decreased respiratory rate


Answers: A, B, D
Rationale: Early = compensation (fast breathing, alkalosis, anxiety). Cyanosis and ↓RR are late.

100

Why is PEEP used in ARDS?

A. Improve cardiac output
B. Reduce inflammation
C. Keep alveoli open
D. Increase hemoglobin


Answer: C
Rationale: PEEP keeps alveoli open at the end of exhalation, preventing collapse and improving oxygenation. It does not directly affect inflammation, cardiac output, or hemoglobin.

100

A ventilated patient develops fever, increased secretions, and a new infiltrate on chest x-ray.

What is the priority concern?

A. Barotrauma
B. ARDS progression
C. Ventilator-associated pneumonia
D. Volutrauma


Answer: C
Rationale: VAP is common in intubated patients because the ET tube bypasses normal defenses, allowing bacteria into the lungs. Fever, secretions, and infiltrates are classic signs.

100

Which are hallmark features of ARDS?

A. Refractory hypoxemia
B. Elevated wedge pressure
C. Bilateral infiltrates
D. Decreased lung compliance
E. Rapid improvement with oxygen


Answers: A, C, D
Rationale:

  • A: Correct — oxygen does not improve levels
  • B: Incorrect — wedge pressure is normal (not heart failure)
  • C: Correct — seen on chest x-ray
  • D: Correct — stiff lungs
  • E: Incorrect — oxygen does NOT fix ARDS
200

A patient with pneumonia is worsening. Which findings indicate progression to ARDS?

A. Hypoxemia not improving with oxygen
B. Bilateral infiltrates on chest x-ray
C. Elevated wedge pressure
D. Decreased lung compliance
E. Productive cough


Answers: A, B, D
Rationale: ARDS = refractory hypoxemia, bilateral infiltrates, stiff lungs. Wedge pressure is normal.

200

A patient becomes drowsy with shallow respirations after being tachypneic earlier.

What is happening?

A. Improvement
B. Anxiety relief
C. Fatigue and deterioration
D. Pain control effect


Answer: C
Rationale: Transition from compensation → respiratory failure.

200

Which are effects of PEEP?

A. Prevents alveolar collapse
B. Decreases oxygenation
C. Increases intrathoracic pressure
D. Improves oxygenation
E. Can cause lung injury


Answers: A, C, D, E
Rationale:

  • A: Correct — PEEP keeps alveoli open
  • B: Incorrect — PEEP improves, not decreases, oxygenation
  • C: Correct — increases intrathoracic pressure
  • D: Correct — improves oxygen exchange
  • E: Correct — excessive PEEP can cause barotrauma/volutrauma
200

Which complications are associated with ARDS treatment?

A. Stress ulcers
B. Renal failure
C. Barotrauma
D. Volutrauma
E. Hyperkalemia


Answers: A, B, C, D
Rationale:

  • A: Correct — stress response + decreased GI perfusion
  • B: Correct — poor perfusion and hypoxia affect kidneys
  • C: Correct — high pressures damage alveoli
  • D: Correct — large volumes overstretch alveoli
  • E: Incorrect — not a primary ARDS complication
200

Which patient is highest priority?

A. Mild dyspnea with normal ABG
B. Productive cough with fever
C. Anxiety with tachypnea
D. Hypoxemia despite 80% FiO₂


Answer: D
Rationale: This indicates refractory hypoxemia → ARDS → immediate intervention needed.

300

A patient initially presents with ALI but improves after antibiotics and oxygen therapy.

What explains this?

A. ARDS always resolves quickly
B. ALI can be reversible
C. ARDS was misdiagnosed
D. Hypoxemia was unrelated

Answer: B
Rationale: Not all ALI progresses to ARDS if treated early.

300

Which findings indicate late ARDS?

A. Confusion
B. Tachypnea with alkalosis
C. Cyanosis
D. Accessory muscle use
E. Hypoxemia despite oxygen


Answers: A, C, D, E
Rationale: Late = severe hypoxia + fatigue. Alkalosis is early.

300

After increasing PEEP, a patient develops sudden hypoxia and absent breath sounds on one side.

What is most likely?

A. Atelectasis
B. Barotrauma
C. Pneumonia
D. Pulmonary edema


Answer: B
Rationale: High PEEP can cause alveolar rupture (barotrauma), leading to pneumothorax, which presents as sudden hypoxia and absent breath sounds on one side.

300

Which describes volutrauma?

A. Infection due to ventilator use
B. Pressure-induced alveolar rupture
C. Overstretching of alveoli from large volumes
D. Fluid accumulation in lungs


Answer: C
Rationale: Volutrauma occurs when alveoli are overdistended from large tidal volumes. Pressure damage is barotrauma.

300

Which findings differentiate ARDS from heart failure?

A. Elevated BNP
B. Normal wedge pressure
C. Bilateral infiltrates
D. Cardiac cause present
E. Non-cardiac lung injury


Answers: B, C, E
Rationale:

  • B: Correct — ARDS has normal wedge pressure
  • C: Correct — both may have infiltrates
  • E: Correct — ARDS is non-cardiac
  • A/D: Incorrect — point toward heart failure
400

Which patients are at highest risk for developing ARDS?

A. Patient with pancreatitis
B. Patient with asthma exacerbation
C. Patient with sepsis
D. Patient after aspiration event
E. Patient with stable COPD


Answers: A, C, D
Rationale: Indirect (sepsis, pancreatitis) and direct (aspiration) causes → ARDS risk.

400

Which ABG indicates worsening ARDS?

A. pH 7.48, CO₂ 30
B. pH 7.50, CO₂ 28
C. pH 7.36, CO₂ 42
D. pH 7.25, CO₂ 55


Answer: D
Rationale: CO₂ retention + acidosis = failure.

400

Which interventions improve oxygenation in ARDS?

A. Mechanical ventilation
B. Oxygen therapy alone
C. Prone positioning
D. PEEP
E. Decreasing FiO₂

Answers: A, C, D
Rationale:

  • A: Correct — provides ventilatory support
  • B: Incorrect — oxygen alone is not effective in ARDS
  • C: Correct — prone improves lung expansion and oxygenation
  • D: Correct — PEEP keeps alveoli open
  • E: Incorrect — decreasing FiO₂ worsens oxygenation
400

Why are ARDS patients at risk for stress ulcers?

A. Increased GI perfusion
B. Critical illness stress response
C. Ventilator use
D. Decreased blood flow to GI tract
E. Increased oral intake


Answers: B, C, D
Rationale:

  • B: Correct — stress increases acid and mucosal breakdown
  • C: Correct — ventilated patients are critically ill
  • D: Correct — poor perfusion damages GI lining
  • A/E: Incorrect — opposite of what happens
400

A patient is hypoxic despite oxygen and is becoming confused and fatigued.

What is the priority intervention?

A. Encourage fluids
B. Provide reassurance
C. Reposition patient
D. Prepare for intubation


Answer: D
Rationale: These are signs of respiratory failure. The airway must be secured immediately.

500

A patient requires 80% FiO₂ but remains hypoxic. What does this indicate?

A. ALI improving
B. Anxiety
C. ARDS
D. Mild hypoventilation


Answer: C
Rationale: Hypoxemia despite high oxygen = hallmark ARDS.

500

A patient is deteriorating. Which signs indicate need for intubation?

A. Decreasing respiratory rate
B. Mild tachypnea
C. Confusion
D. Increasing work of breathing
E. Hypoxemia despite oxygen


Answers: A, C, D, E
Rationale: These show failure. Mild tachypnea alone is early.

500

Why must PEEP be increased gradually?

A. Prevent infection
B. Improve comfort
C. Avoid lung damage
D. Reduce anxiety


Answer: C
Rationale: Increasing PEEP too quickly can cause barotrauma (pressure damage) and volutrauma (overstretching). Gradual increases allow safe recruitment of alveoli without injury.

500

A patient with ARDS develops decreased urine output and rising creatinine.

What is the most likely cause?

A. Fluid overload
B. Kidney infection
C. Increased oxygen delivery
D. Poor perfusion and hypoxia


Answer: D
Rationale: ARDS causes systemic hypoxia and often hypotension, leading to decreased kidney perfusion and acute kidney injury.

500

Which interventions are essential in ARDS management?

A. Mechanical ventilation
B. PEEP
C. Prone positioning
D. Treat underlying cause
E. Withhold oxygen


Answers: A, B, C, D
Rationale:

  • A: Correct — supports ventilation
  • B: Correct — keeps alveoli open
  • C: Correct — improves oxygenation
  • D: Correct — must fix cause
  • E: Incorrect — oxygen is still used (just not sufficient alone)