Respiratory failure Flashcards
Respiratory Failure / Will Kill)
A 68-year-old with COPD exacerbation is found to have a PaO₂ of 50 mm Hg and PaCO₂ of 72 mm Hg. What is the most crucial immediate intervention?
A. Noninvasive or invasive ventilation support
B. IV furosemide
C. Routine laboratory tests
D. High-flow intravenous fluids
Correct Answer: A. Noninvasive or invasive ventilation support
Rationale:
In a patient with both significant hypoxemia (low PaO₂) and hypercapnia (elevated PaCO₂), the immediate concern is respiratory failure. Providing ventilation support—whether noninvasive (e.g., BiPAP) or invasive (endotracheal intubation)—is crucial to improve oxygenation and eliminate excess carbon dioxide. Other options, such as IV furosemide, routine laboratory tests, or high-flow IV fluids, do not address the critical ventilatory failure present in this scenario.
Respiratory Failure / Will Harm)
Which iatrogenic error is most likely to harm a patient in acute respiratory failure?
A. Delaying oxygen therapy until ABG results are back
B. Giving low-flow supplemental oxygen
C. Using short-course steroids
D. Ambulation with close monitoring
Correct Answer: A. Delaying oxygen therapy until ABG results are back
Rationale:
Delaying oxygen therapy in a patient with acute respiratory failure can worsen hypoxemia and lead to further deterioration. Immediate oxygen supplementation is essential, even before ABG results are obtained. The other options, such as low-flow supplemental oxygen, short-course steroids, or ambulation with close monitoring, are generally safe or beneficial when appropriately used.
- (Respiratory Failure / Really Common)
In acute hypoxemic respiratory failure, which monitoring parameter is most commonly used to guide management decisions?
A. 12-lead EKG
B. Arterial blood gas (ABG)
C. Liver function tests
D. Echocardiography
Correct Answer: B. Arterial blood gas (ABG)
Rationale:
ABG analysis is critical in the management of acute hypoxemic respiratory failure as it provides direct measurements of oxygenation, ventilation (PaCO₂), and acid-base status. This information is essential for guiding therapeutic interventions, such as the need for ventilation support. Other tests like a 12-lead EKG, liver function tests, or echocardiography do not offer the immediate respiratory parameters needed for this clinical decision-making.
- Which of the following best defines respiratory failure?
A. A condition where oxygen saturation is 95%
B. Inability to maintain normal gas exchange (PaO₂ <60 mm Hg or PaCO₂ >50 mm Hg)
C. Mild dyspnea during exercise
D. Hyperventilation with low CO₂
o Answer: B
o Rationale: Respiratory failure is defined by impaired gas exchange leading to hypoxemia and/or hypercapnia.
- A patient with COPD develops worsening dyspnea and confusion. Which parameter “will kill your patient” if not corrected promptly?
A. Elevated PaCO₂ causing respiratory acidosis
B. Mild tachypnea
C. Slightly increased respiratory rate
D. Normal oxygen saturation
o Answer: A
o Rationale: Severe hypercapnia and acidosis can depress the central nervous system and lead to respiratory arrest.
- What is “really common” as a cause of respiratory failure in hospitalized patients?
A. Trauma-induced apnea
B. Pneumonia leading to hypoxemia
C. Asthma only
D. Cardiac arrhythmia
o Answer: B
o Rationale: Pneumonia is one of the most common causes of acute respiratory failure.
- Which intervention is key in managing acute respiratory failure?
A. Immediate initiation of high-dose diuretics
B. Airway stabilization and oxygen therapy
C. Exclusive use of bronchodilators
D. Avoiding positive-pressure ventilation.
o Answer: B
o Rationale: Ensuring a patent airway and supporting oxygenation are the first priorities (the “A” and “B” in ABCs)
- In respiratory failure, which nonpharmacologic therapy is “really common” for improving oxygenation?
A. Prone positioning
B. Complete bed rest
C. Fluid restriction
D. High-dose corticosteroids
o Answer: A
o Rationale: Prone positioning is commonly used in ARDS to improve oxygenation.
A 72-year-old man with COPD presents with increasing dyspnea and confusion. His ABG shows pH 7.28, PaCO₂ 68 mmHg, and PaO₂ 55 mmHg on room air. What is the most likely diagnosis?
A) Type 1 respiratory failure
B) Type 2 respiratory failure
C) Acute respiratory distress syndrome (ARDS)
D) Pulmonary embolism
Answer: B
Rationale: Type 2 respiratory failure (hypercapnic) is defined by PaCO₂ >45 mmHg and pH <7.35 due to alveolar hypoventilation, often seen in COPD exacerbations.
A 60-year-old woman with pneumonia presents with dyspnea and SpO₂ of 85% on room air. ABG shows pH 7.40, PaCO₂ 38 mmHg, and PaO₂ 55 mmHg. What type of respiratory failure does she have?
A) Type 1 respiratory failure
B) Type 2 respiratory failure
C) Type 3 respiratory failure
D) Type 4 respiratory failure
Answer: A
Rationale: Type 1 respiratory failure (hypoxemic) is defined by PaO₂ <60 mmHg with normal or low PaCO₂, commonly caused by pneumonia, ARDS, or PE.
Which of the following is the most appropriate initial intervention for a patient with type 1 respiratory failure due to pulmonary edema?
A) High-flow nasal cannula oxygen
B) Non-invasive positive pressure ventilation (NIPPV)
C) Intubation with mechanical ventilation
D) Diuretics and afterload reduction
Answer: D
Rationale: Pulmonary edema is commonly managed with diuretics and afterload reduction (e.g., nitroglycerin), while oxygen therapy supports ventilation.
- In respiratory failure, which nonpharmacologic therapy is “really common” for improving oxygenation?
A. Prone positioning
B. Complete bed rest
C. Fluid restriction
D. High-dose corticosteroids
o Answer: A
o Rationale: Prone positioning is commonly used in ARDS to improve oxygenation.
A 40-year-old man with Guillain-Barré syndrome develops progressive respiratory distress. Which of the following ABG findings would most indicate the need for mechanical ventilation?
A) pH 7.45, PaCO₂ 40 mmHg, PaO₂ 70 mmHg
B) pH 7.30, PaCO₂ 55 mmHg, PaO₂ 60 mmHg
C) pH 7.40, PaCO₂ 40 mmHg, PaO₂ 50 mmHg
D) pH 7.48, PaCO₂ 30 mmHg, PaO₂ 65 mmHg
Answer: B
Rationale: Hypercapnic respiratory acidosis (PaCO₂ >50 mmHg with pH <7.35) suggests impending respiratory failure, requiring mechanical ventilation.
A 62-year-old man with congestive heart failure presents with acute respiratory distress. He is tachypneic and hypoxic. What diagnostic tool would best assess his respiratory failure cause?
A) Pulmonary function test
B) Echocardiogram
C) Chest X-ray
D) Arterial blood gas
Answer: C
Rationale: Chest X-ray is the first-line imaging to evaluate pulmonary edema, pneumonia, or lung collapse in respiratory distress
A 50-year-old patient with obesity-hypoventilation syndrome presents with morning headaches and daytime sleepiness. ABG shows pH 7.34, PaCO₂ 55 mmHg, and PaO₂ 60 mmHg. What is the best long-term management?
A) Continuous positive airway pressure (CPAP)
B) Bi-level positive airway pressure (BiPAP)
C) High-flow nasal oxygen
D) Endotracheal intubation
Answer: B
Rationale: Obesity-hypoventilation syndrome (OHS) leads to chronic hypercapnia and benefits most from BiPAP to support ventilation.
Which of the following conditions most commonly causes type 2 respiratory failure?
A) Pulmonary embolism
B) ARDS
C) COPD
D) High-altitude exposure
Answer: C
Rationale: COPD exacerbations often result in alveolar hypoventilation, leading to hypercapnic respiratory failure (type 2).
Which intervention is most appropriate for a patient with respiratory failure due to opioid overdose?
A) High-flow oxygen
B) Non-invasive ventilation
C) Naloxone administration
D) Inhaled bronchodilators
Answer: C
Rationale: Opioid overdose leads to decreased respiratory drive (won’t breathe) and is best treated with naloxone.
A patient in respiratory failure has a chest X-ray showing bilateral opacities without cardiogenic pulmonary edema. What is the most likely diagnosis?
A) ARDS
B) Pulmonary embolism
C) COPD exacerbation
D) Pneumothorax
Answer: A
Rationale: ARDS is diagnosed based on bilateral lung opacities on imaging, respiratory failure, and lack of cardiac failure.
Which of the following is a common complication of prolonged mechanical ventilation?
A) Pulmonary embolism
B) Tracheomalacia
C) Hypercapnia
D) Pneumothorax
Answer: D
Rationale: Barotrauma from mechanical ventilation increases the risk of pneumothorax.
Which factor increases the risk of ventilator-associated pneumonia (VAP)?
A) Early extubation
B) Head of bed elevation
C) Frequent sedation interruptions
D) Prolonged intubation
Answer: D
Rationale: Longer intubation times increase the risk of VAP due to bacterial colonization.
Which of the following best defines acute hypercapnic respiratory failure?
A) PaCO₂ >50 mmHg and pH <7.35
B) PaCO₂ <35 mmHg and pH >7.45
C) PaO₂ <60 mmHg on room air
D) Normal PaO₂ with low SaO₂
Answer: A
Rationale: Type 2 respiratory failure is defined as PaCO₂ >50 mmHg with respiratory acidosis.
A patient with myasthenia gravis is at risk for respiratory failure due to:
A) Airway obstruction
B) Reduced central respiratory drive
C) Neuromuscular weakness
D) V/Q mismatch
Answer: C
Rationale: Neuromuscular weakness (can’t breathe) leads to type 2 respiratory failure in myasthenia gravis.
A patient with severe ARDS is placed on mechanical ventilation. What strategy reduces ventilator-induced lung injury?
A) High tidal volume ventilation
B) Permissive hypercapnia
C) Immediate neuromuscular blockade
D) High oxygen fraction (FiO₂ >90%)
Answer: B
Rationale: Permissive hypercapnia with low tidal volumes reduces barotrauma in ARDS.
Which of the following conditions can cause both type 1 and type 2 respiratory failure?
A) Guillain-Barré syndrome
B) Pneumothorax
C) ARDS
D) Pulmonary embolism
Answer: A
Rationale: Guillain-Barré syndrome can cause hypoxemia (type 1) and hypercapnia (type 2) due to respiratory muscle paralysis.
A 68-year-old man with COPD is admitted for worsening dyspnea. He is somnolent with a respiratory rate of 10 breaths per minute. ABG shows pH 7.25, PaCO₂ 72 mmHg, and PaO₂ 58 mmHg. What is the next best step?
A) Intubation and mechanical ventilation
B) Supplemental oxygen at 10 L/min via nasal cannula
C) Noninvasive positive pressure ventilation (BiPAP)
D) IV corticosteroids and nebulized albuterol
Answer: C
Rationale: BiPAP is preferred for acute hypercapnic respiratory failure due to COPD exacerbation unless the patient is in severe distress or has altered mental status, requiring intubation.
A 45-year-old woman presents with acute respiratory distress. She has a history of opioid use. ABG shows pH 7.22, PaCO₂ 78 mmHg, and PaO₂ 65 mmHg. What is the most appropriate next step?
A) Start high-flow oxygen
B) Administer naloxone
C) Intubate immediately
D) Obtain a CT scan of the chest
Answer: B
Rationale: Opioid overdose leads to central respiratory depression (won’t breathe), causing hypercapnic respiratory failure, which is reversed with naloxone
A patient with ARDS is placed on mechanical ventilation. Which setting adjustment is most appropriate to prevent ventilator-induced lung injury?
A) Increase tidal volume to 10 mL/kg
B) Set FiO₂ at 100%
C) Use low tidal volume ventilation (6 mL/kg)
D) Maintain PEEP at 0 cm H₂O
Answer: C
Rationale: Low tidal volume ventilation (6 mL/kg) reduces barotrauma and improves survival in ARDS.
A 70-year-old woman with a history of congestive heart failure presents with acute hypoxemic respiratory failure. Chest X-ray shows bilateral pulmonary edema. Which intervention is most appropriate?
A) Intubation and mechanical ventilation
B) Noninvasive positive pressure ventilation (NIPPV)
C) High-dose corticosteroids
D) Nebulized bronchodilators
Answer: B
Rationale: NIPPV (e.g., BiPAP) reduces the need for intubation in acute cardiogenic pulmonary edema by improving oxygenation and decreasing work of breathing
A 55-year-old man with severe pneumonia has been on mechanical ventilation for 7 days. He suddenly develops fever, increased secretions, and worsening oxygenation. What is the most likely diagnosis?
A) Pulmonary embolism
B) Ventilator-associated pneumonia (VAP)
C) ARDS
D) Pneumothorax
Answer: B
Rationale: New fever, increased secretions, and worsening oxygenation after 48 hours of intubation suggest ventilator-associated pneumonia (VAP).
A 65-year-old man with end-stage COPD presents with dyspnea and respiratory acidosis. He refuses intubation. What is the best next step?
A) Provide palliative care only
B) Offer noninvasive ventilation (BiPAP)
C) Administer IV corticosteroids
D) Increase oxygen to 100% FiO₂.
Answer: B
Rationale: BiPAP is the best option for hypercapnic respiratory failure in a patient who refuses intubation
A 50-year-old man is found unconscious. His ABG reveals pH 7.15, PaCO₂ 90 mmHg, and PaO₂ 60 mmHg. What is the best next step?
A) BiPAP
B) Endotracheal intubation
C) High-flow nasal oxygen
D) Nebulized bronchodilators
Answer: B
Rationale: Severe hypercapnia with respiratory acidosis and altered mental status requires immediate intubation.
Which intervention is most appropriate for preventing ventilator-associated pneumonia (VAP)?
A) Administer prophylactic antibiotics
B) Routine endotracheal suctioning
C) Elevate the head of the bed
D) Frequent deep sedation.
Answer: C
Rationale: Elevating the head of the bed (>30 degrees) reduces the risk of aspiration and VAP
Which of the following is a major cause of type 1 (hypoxemic) respiratory failure?
A) Myasthenia gravis
B) Neuromuscular blockade
C) ARDS
D) Opioid overdose
Answer: C
Rationale: ARDS causes severe V/Q mismatch and leads to type 1 respiratory failure.
A 78-year-old woman with COPD is admitted for respiratory failure. She has been on 2 L of oxygen at home. ABG on 6 L of oxygen shows pH 7.29, PaCO₂ 65 mmHg, and PaO₂ 140 mmHg. What is the most likely cause of her worsening condition?
A) Oxygen-induced hypercapnia
B) Pulmonary embolism
C) Acute respiratory distress syndrome (ARDS)
D) Myasthenia gravis exacerbation
Answer: A
Rationale: In COPD, excessive oxygen can suppress hypoxic drive, leading to CO₂ retention and worsening hypercapnic respiratory failure
Hypoxemia (PaO₂ <60 mmHg), normal or low PaCO₂ → Causes: ARDS, pneumonia, PE
Type 1 respiratory failure
Hypercapnia (PaCO₂ >50 mmHg), respiratory acidosis → Causes: COPD, opioid overdose, neuromuscular disorders
Type 2 respiratory failure
BiPAP for COPD and CHF exacerbations →
Prevents intubation in hypercapnic or hypoxemic failure
Indication for intubation
Intubation for respiratory acidosis with altered mental status
ARDS management
Low tidal volume ventilation (6 mL/kg), permissive hypercapnia, and high PEEP
Head of bed elevation, daily sedation breaks, early extubation when possible
VAP prevention
High FiO₂ in COPD can suppress hypoxic drive and worsen hypercapnia
Oxygen-induced hypercapnia
ARDS / Will Kill)
A 58-year-old with septic shock develops bilateral infiltrates and refractory hypoxemia. Which hallmark complication leads to high mortality if not corrected?
A. Mild alveolar edema
B. Persistent hypoxemia with multi-organ failure
C. Unilateral consolidation
D. Bronchospasm alone
Correct Answer: B. Persistent hypoxemia with multi-organ failure
Rationale:
In ARDS, refractory hypoxemia can quickly progress to multi-organ failure if not aggressively managed. This systemic involvement is the primary contributor to the high mortality associated with ARDS. Mild alveolar edema, unilateral consolidation, or bronchospasm alone do not encapsulate the full severity of the condition.
- (ARDS / Will Harm)
Which ventilator strategy is most harmful if used in ARDS management?
A. Low tidal volumes (4–6 mL/kg IBW)
B. High tidal volumes (>10 mL/kg)
C. Adequate PEEP for alveolar recruitment
D. Prone positioning
Correct Answer: B. High tidal volumes (>10 mL/kg)
Rationale:
Using high tidal volumes in ARDS can lead to ventilator-induced lung injury by overdistending the already injured alveoli. In contrast, low tidal volumes (4–6 mL/kg IBW), adequate PEEP for alveolar recruitment, and prone positioning are part of lung-protective strategies that improve outcomes in ARDS patients
- (ARDS / Really Common)
In moderate to severe ARDS, which nonpharmacologic intervention is commonly used to improve oxygenation?
A. Prone positioning
B. Immediate extubation
C. Routine bronchoscopy
D. Fluid overload
Correct Answer: A. Prone positioning
Rationale:
Prone positioning is a widely recognized nonpharmacologic intervention for improving oxygenation in moderate to severe ARDS. It enhances ventilation-perfusion matching and reduces ventilator-induced lung injury. Immediate extubation, routine bronchoscopy, or fluid overload are not beneficial in this setting and may worsen the patient’s condition.
ARDS / Pathophysiology)
ARDS is primarily characterized by:
A. Cardiogenic pulmonary edema
B. Diffuse alveolar damage with increased capillary permeability
C. Isolated bronchospasm
D. Focal neoplasm of the lung
Correct Answer: B. Diffuse alveolar damage with increased capillary permeability
Rationale:
ARDS is defined by diffuse alveolar damage that leads to increased capillary permeability and subsequent noncardiogenic pulmonary edema. This distinguishes it from conditions like cardiogenic pulmonary edema or isolated bronchospasm, and it is not related to focal neoplastic processes.
For lung-protective ventilator strategies, what is the goal tidal volume for a patient in acute respiratory distress syndrome?
A. 4–6 ml/kg of ideal body weight
B. 6–8 ml/kg of ideal body weight
C. 2–4 ml/kg of ideal body weight
D. 8–10 ml/kg of ideal body weight
Correct Answer: A. 4–6 ml/kg of ideal body weight
Rationale:
Lung-protective ventilator strategies in ARDS aim to minimize ventilator-induced lung injury. This is achieved by using low tidal volumes—typically 4–6 ml/kg of ideal body weight—to reduce overdistension of the alveoli while maintaining adequate ventilation.
Hypoxemia in acute respiratory distress syndrome is from an intrapulmonary shunt. How is this treated?
A. Increase FiO2
B. Decrease minute ventilation
C. Decrease tidal volume
D. Increase peak end expiratory pressure
Correct Answer: D. Increase peak end expiratory pressure (PEEP)
Rationale:
In ARDS, hypoxemia primarily results from an intrapulmonary shunt due to alveolar collapse and fluid-filled alveoli. Increasing PEEP helps by recruiting these collapsed alveoli, thereby reducing the shunt fraction and improving oxygenation. While increasing FiO₂ may provide some benefit, it is less effective if alveoli remain collapsed, making PEEP the preferred intervention in this scenario.
On CT scan, what differentiates acute respiratory distress syndrome (ARDS) from pneumonia?
A. Consolidation only in the bases of the lungs with ARDS
B. Consolidation throughout with ground-glass appearance with ARDS
C. Kerley B lines present in pneumonia but not ARDS
D. Enlarged mediastinum appreciated for pneumonia
B. Consolidation throughout with ground-glass appearance with ARDS
You have a patient who is being mechanically ventilated. As the advanced practice registered nurse, you know there are different modes for managing respiratory failure. What mode would you want to use to have complete control of the patient’s breathing?
A. Pressure control
B. Pressure-regulated volume control
C. BiPAP
D. Synchronized intermittent mandatory ventilation
B. Pressure-regulated volume control
- ARDS is characterized by which of the following pathophysiologic features?
A. Increased lung compliance and reduced edema
B. Diffuse alveolar damage, increased permeability, and noncardiogenic pulmonary edema
C. Isolated bronchospasm
D. Focal consolidation in one lung lobe
o Answer: B
o Rationale: ARDS is defined by diffuse alveolar damage, increased capillary permeability, and resultant pulmonary edema not due to cardiac failure.
- Which factor “will kill your patient” in ARDS if not managed appropriately?
A. Mild cough
B. Refractory hypoxemia and multi-organ failure
C. Occasional desaturation
D. Low-grade fever
o
Answer: B
o Rationale: Refractory hypoxemia leading to multi-organ dysfunction is the primary cause of death in ARDS.
- What is a “common” initial nonpharmacologic management strategy in ARDS?
A. High tidal volume ventilation
B. Low tidal volume mechanical ventilation
C. Unmonitored oxygen therapy
D. Immediate extubation
o Answer: B
o Rationale: Low tidal volume ventilation is standard care in ARDS to minimize ventilator-induced lung injury.
- Which complication “will harm your patient” if a patient with ARDS is ventilated with high tidal volumes?
A. Improved oxygenation
B. Ventilator-induced lung injury (barotrauma)
C. Enhanced lung compliance
D. Reduction in inflammatory cytokines
o Answer: B
o Rationale: High tidal volumes can cause barotrauma, worsening lung injury.
- In ARDS, which adjunctive therapy may be used in refractory hypoxemia?
A. Prone positioning
B. Increased tidal volume
C. Fluid overload
D. Routine use of bronchodilators only
o Answer: A
o Rationale: Prone positioning improves oxygenation in ARDS by redistributing ventilation.
Answer: C
Rationale: A PaO₂/FiO₂ of 120 indicates moderate ARDS. Low tidal volume ventilation and prone positioning can improve oxygenation.
A 72-year-old man with COPD presents with increasing dyspnea and confusion. His ABG shows pH 7.28, PaCO₂ 68 mmHg, and PaO₂ 55 mmHg on room air. What is the most likely diagnosis?
A) Type 1 respiratory failure
B) Type 2 respiratory failure
C) Acute respiratory distress syndrome (ARDS)
D) Pulmonary embolism
Answer: B
Rationale: Type 2 respiratory failure (hypercapnic) is defined by PaCO₂ >45 mmHg and pH <7.35 due to alveolar hypoventilation, often seen in COPD exacerbations.
A 60-year-old woman with pneumonia presents with dyspnea and SpO₂ of 85% on room air. ABG shows pH 7.40, PaCO₂ 38 mmHg, and PaO₂ 55 mmHg. What type of respiratory failure does she have?
A) Type 1 respiratory failure
B) Type 2 respiratory failure
C) Type 3 respiratory failure
D) Type 4 respiratory failure
Answer: A
Rationale: Type 1 respiratory failure (hypoxemic) is defined by PaO₂ <60 mmHg with normal or low PaCO₂, commonly caused by pneumonia, ARDS, or PE.
Which of the following is the most appropriate initial intervention for a patient with type 1 respiratory failure due to pulmonary edema?
A) High-flow nasal cannula oxygen
B) Non-invasive positive pressure ventilation (NIPPV)
C) Intubation with mechanical ventilation
D) Diuretics and afterload reduction
Answer: D
Rationale: Pulmonary edema is commonly managed with diuretics and afterload reduction (e.g., nitroglycerin), while oxygen therapy supports ventilation.
4.
A 40-year-old man with Guillain-Barré syndrome develops progressive respiratory distress. Which of the following ABG findings would most indicate the need for mechanical ventilation?
A) pH 7.45, PaCO₂ 40 mmHg, PaO₂ 70 mmHg
B) pH 7.30, PaCO₂ 55 mmHg, PaO₂ 60 mmHg
C) pH 7.40, PaCO₂ 40 mmHg, PaO₂ 50 mmHg
D) pH 7.48, PaCO₂ 30 mmHg, PaO₂ 65 mmHg
Answer: B
Rationale: Hypercapnic respiratory acidosis (PaCO₂ >50 mmHg with pH <7.35) suggests impending respiratory failure, requiring mechanical ventilation.
5.
A 50-year-old patient with obesity-hypoventilation syndrome presents with morning headaches and daytime sleepiness. ABG shows pH 7.34, PaCO₂ 55 mmHg, and PaO₂ 60 mmHg. What is the best long-term management?
A) Continuous positive airway pressure (CPAP)
B) Bi-level positive airway pressure (BiPAP)
C) High-flow nasal oxygen
D) Endotracheal intubation
Answer: B
Rationale: Obesity-hypoventilation syndrome (OHS) leads to chronic hypercapnia and benefits most from BiPAP to support ventilation.
A patient with ARDS is intubated. Which ventilatory strategy is most appropriate?
A) High tidal volume ventilation (10-12 mL/kg)
B) Low tidal volume ventilation (6 mL/kg) with high PEEP
C) Permissive hypercapnia and FiO₂ 100%
D) No PEEP and aggressive fluid resuscitation
Answer: B
Rationale: Low tidal volume ventilation reduces ventilator-induced lung injury in ARDS, and high PEEP prevents alveolar collapse.
A patient with ARDS is on mechanical ventilation with low tidal volume settings. However, their PaO₂/FiO₂ ratio remains <100 despite high PEEP. Which next step could help improve oxygenation?
A) Increase tidal volume
B) Prone positioning
C) Bronchodilator therapy
D) Lower respiratory rate
Answer: B
Rationale: Prone positioning can drastically improve oxygenation by enhancing ventilation-perfusion matching in severe ARDS.
Which factor is most critical for improving long-term outcomes in survivors of severe ARDS?
A) Early initiation of high-dose steroids
B) Routine use of noninvasive ventilation
C) Aggressive fluid resuscitation
D) Adequate nutrition and physical rehabilitation
Answer: D
Rationale: Appropriate nutrition, rehabilitation, and supportive care to prevent deconditioning enhances post-ICU recovery in ARDS survivors.
normal/low PCWP, PaO₂/FiO₂ ratio <300, bilateral infiltrates, treat with low tidal volumes, high PEEP, prone positioning in severe cases.
ARDS
A patient presents with severe dyspnea, diffuse pulmonary infiltrates, and hypoxia refractory to oxygen therapy. BNP is normal. What is the most likely diagnosis?
A) Cardiogenic pulmonary edema
B) Pulmonary embolism
C) Acute respiratory distress syndrome (ARDS)
D) Pneumonia
Answer: C
Rationale: Normal BNP and refractory hypoxia with diffuse infiltrates suggest ARDS rather than cardiogenic pulmonary edema.
Which of the following is a hallmark feature of ARDS on chest X-ray?
A) Unilateral consolidation
B) Bilateral diffuse infiltrates
C) Pleural effusion
D) Perihilar “batwing” appearance.
Answer: B
Rationale: ARDS presents with bilateral diffuse infiltrates on chest X-ray, often appearing as “white-out” lungs
Which ventilatory strategy is recommended for ARDS to minimize ventilator-induced lung injury?
A) Low tidal volume (6 mL/kg) ventilation
B) High tidal volume (12 mL/kg) ventilation
C) No PEEP and high FiO2
D) CPAP only
Answer: A
Rationale: Low tidal volume ventilation reduces volutrauma and barotrauma in ARDS
A patient with ARDS is on mechanical ventilation. Their PaO₂/FiO₂ ratio is 80. How would you classify their ARDS severity?
A) Mild
B) Moderate
C) Severe
D) Not ARDS
Answer: C
Rationale: PaO₂/FiO₂ ratio <100 indicates severe ARDS.
Which of the following best differentiates ARDS from cardiogenic pulmonary edema?
A) Pulmonary capillary wedge pressure (PCWP)
B) Chest X-ray
C) BNP levels
D) Clinical presentation
Answer: A
Rationale: PCWP is normal or low in ARDS but elevated in cardiogenic pulmonary edema.
A patient with ARDS has a PaO₂/FiO₂ ratio of 150. How would this be classified?
A) Mild ARDS
B) Moderate ARDS
C) Severe ARDS
D) Not ARDS
Answer: B
Rationale: PaO₂/FiO₂ ratio between 100-200 indicates moderate ARDS.
Which intervention is most effective in improving oxygenation in severe ARDS?
A) Prone positioning
B) Diuretics
C) Noninvasive ventilation
D) Bronchodilators
Answer: A
Rationale: Prone positioning improves ventilation-perfusion matching and lung recruitment in severe ARDS.
What is the most common direct cause of ARDS?
A) Sepsis
B) Pneumonia
C) Pancreatitis
D) Blood transfusion
Answer: B
Rationale: Pneumonia is the most common direct cause of ARDS.
A 45-year-old man with pancreatitis develops respiratory failure. His chest X-ray shows diffuse infiltrates, and he is hypoxic despite high-flow oxygen. Which of the following is the most likely diagnosis?
A) Cardiogenic pulmonary edema
B) Pulmonary embolism
C) ARDS
D) COPD exacerbation
Answer: C
Rationale: Pancreatitis is a common non-pulmonary cause of ARDS.
Which of the following is contraindicated in the management of ARDS?
A) Low tidal volume ventilation
B) High PEEP
C) Routine corticosteroids
D) Prone positioning
Answer: C
Rationale: Routine corticosteroids are not recommended in all cases of ARDS unless there is a strong indication.
Which laboratory finding is most consistent with ARDS?
A) High BNP
B) Low pulmonary capillary wedge pressure
C) Increased left ventricular ejection fraction
D) Hyperchloremic metabolic acidosis
Answer: B
Rationale: ARDS is a noncardiogenic cause of pulmonary edema, so PCWP is normal or low.
Which of the following pathophysiologic processes contributes most to ARDS?
A) Pulmonary capillary hypertension
B) Increased alveolar capillary permeability
C) Hypovolemia
D) Right ventricular failure
Answer: B
Rationale: Increased capillary permeability leads to pulmonary edema in ARDS.
A 50-year-old man with ARDS remains hypoxic despite high FiO₂. What is the best next step?
A) Increase FiO₂ to 100%
B) Start diuretics
C) Prone positioning
D) Give IV steroids
Answer: C
Rationale: Prone positioning improves ventilation-perfusion mismatch in ARDS.
Which of the following best predicts mortality in ARDS?
A) PaO₂/FiO₂ ratio
B) WBC count
C) Serum creatinine
D) Sputum culture results
Answer: A
Rationale: Lower PaO₂/FiO₂ ratio correlates with worse outcomes in ARDS
Which of the following is a late complication of ARDS?
A) Pulmonary fibrosis
B) Hyperkalemia
C) Upper GI bleeding
D) Seizures
Answer: A
Rationale: Some ARDS patients develop pulmonary fibrosis, leading to chronic respiratory failure.
What is the primary cause of hypoxemia in ARDS?
A) Hypoventilation
B) V/Q mismatch and shunting
C) Hypercapnia
D) Bronchospasm
Answer: B
Rationale: Intrapulmonary shunting and ventilation-perfusion mismatch cause refractory hypoxemia in ARDS.
A patient with ARDS has a pH of 7.28 and a PaCO₂ of 60 mmHg. What is the best intervention?
A) Increase tidal volume
B) Increase respiratory rate
C) Decrease PEEP
D) Decrease FiO₂
Answer: B
Rationale: Increasing respiratory rate improves CO₂ clearance in ARDS patients with respiratory acidosis.
A patient with severe ARDS is not improving despite lung-protective ventilation. What is the next step?
A) ECMO
B) High-dose steroids
C) Beta-blockers
D) CPAP
Answer: A
Rationale: Extracorporeal membrane oxygenation (ECMO) is used in refractory severe ARDS.
6.
A 62-year-old man with congestive heart failure presents with acute respiratory distress. He is tachypneic and hypoxic. What diagnostic tool would best assess his respiratory failure cause?
A) Pulmonary function test
B) Echocardiogram
C) Chest X-ray
D) Arterial blood gas
Answer: C
Rationale: Chest X-ray is the first-line imaging to evaluate pulmonary edema, pneumonia, or lung collapse in respiratory distress.
Which of the following conditions most commonly causes type 2 respiratory failure?
A) Pulmonary embolism
B) ARDS
C) COPD
D) High-altitude exposure
Answer: C
Rationale: COPD exacerbations often result in alveolar hypoventilation, leading to hypercapnic respiratory failure (type 2).
Which intervention is most appropriate for a patient with respiratory failure due to opioid overdose?
A) High-flow oxygen
B) Non-invasive ventilation
C) Naloxone administration
D) Inhaled bronchodilators
Answer: C
Rationale: Opioid overdose leads to decreased respiratory drive (won’t breathe) and is best treated with naloxone.
A patient in respiratory failure has a chest X-ray showing bilateral opacities without cardiogenic pulmonary edema. What is the most likely diagnosis?
A) ARDS
B) Pulmonary embolism
C) COPD exacerbation
D) Pneumothorax
Answer: A
Rationale: ARDS is diagnosed based on bilateral lung opacities on imaging, respiratory failure, and lack of cardiac failure.
Which of the following is a common complication of prolonged mechanical ventilation?
A) Pulmonary embolism
B) Tracheomalacia
C) Hypercapnia
D) Pneumothorax
Answer: D
Rationale: Barotrauma from mechanical ventilation increases the risk of pneumothorax
Which factor increases the risk of ventilator-associated pneumonia (VAP)?
A) Early extubation
B) Head of bed elevation
C) Frequent sedation interruptions
D) Prolonged intubation
Answer: D
Rationale: Longer intubation times increase the risk of VAP due to bacterial colonization.
Which of the following best defines acute hypercapnic respiratory failure?
A) PaCO₂ >50 mmHg and pH <7.35
B) PaCO₂ <35 mmHg and pH >7.45
C) PaO₂ <60 mmHg on room air
D) Normal PaO₂ with low SaO₂
Answer: A
Rationale: Type 2 respiratory failure is defined as PaCO₂ >50 mmHg with respiratory
A patient with myasthenia gravis is at risk for respiratory failure due to:
A) Airway obstruction
B) Reduced central respiratory drive
C) Neuromuscular weakness
D) V/Q mismatch
Answer: C
Rationale: Neuromuscular weakness (can’t breathe) leads to type 2 respiratory failure in myasthenia gravis.
Which of the following conditions can cause both type 1 and type 2 respiratory failure?
A) Guillain-Barré syndrome
B) Pneumothorax
C) ARDS
D) Pulmonary embolism
Answer: A
Rationale: Guillain-Barré syndrome can cause hypoxemia (type 1) and hypercapnia (type 2) due to respiratory muscle paralysis.
A patient with severe ARDS is placed on mechanical ventilation. What strategy reduces ventilator-induced lung injury?
A) High tidal volume ventilation
B) Permissive hypercapnia
C) Immediate neuromuscular blockade
D) High oxygen fraction (FiO₂ >90%)
Answer: B
Rationale: Permissive hypercapnia with low tidal volumes reduces barotrauma in ARDS.
A 68-year-old man with COPD is admitted for worsening dyspnea. He is somnolent with a respiratory rate of 10 breaths per minute. ABG shows pH 7.25, PaCO₂ 72 mmHg, and PaO₂ 58 mmHg. What is the next best step?
A) Intubation and mechanical ventilation
B) Supplemental oxygen at 10 L/min via nasal cannula
C) Noninvasive positive pressure ventilation (BiPAP)
D) IV corticosteroids and nebulized albuterol
Answer: C
Rationale: BiPAP is preferred for acute hypercapnic respiratory failure due to COPD exacerbation unless the patient is in severe distress or has altered mental status, requiring intubation.
A 45-year-old woman presents with acute respiratory distress. She has a history of opioid use. ABG shows pH 7.22, PaCO₂ 78 mmHg, and PaO₂ 65 mmHg. What is the most appropriate next step?
A) Start high-flow oxygen
B) Administer naloxone
C) Intubate immediately
D) Obtain a CT scan of the chest
Answer: B
Rationale: Opioid overdose leads to central respiratory depression (won’t breathe), causing hypercapnic respiratory failure, which is reversed with naloxone
A patient with ARDS is placed on mechanical ventilation. Which setting adjustment is most appropriate to prevent ventilator-induced lung injury?
A) Increase tidal volume to 10 mL/kg
B) Set FiO₂ at 100%
C) Use low tidal volume ventilation (6 mL/kg)
D) Maintain PEEP at 0 cm H₂O
Answer: C
Rationale: Low tidal volume ventilation (6 mL/kg) reduces barotrauma and improves survival in ARDS.
A 55-year-old man with severe pneumonia has been on mechanical ventilation for 7 days. He suddenly develops fever, increased secretions, and worsening oxygenation. What is the most likely diagnosis?
A) Pulmonary embolism
B) Ventilator-associated pneumonia (VAP)
C) ARDS
D) Pneumothorax.
Answer: B
Rationale: New fever, increased secretions, and worsening oxygenation after 48 hours of intubation suggest ventilator-associated pneumonia (VAP)
A 70-year-old woman with a history of congestive heart failure presents with acute hypoxemic respiratory failure. Chest X-ray shows bilateral pulmonary edema. Which intervention is most appropriate?
A) Intubation and mechanical ventilation
B) Noninvasive positive pressure ventilation (NIPPV)
C) High-dose corticosteroids
D) Nebulized bronchodilators
Answer: B
Rationale: NIPPV (e.g., BiPAP) reduces the need for intubation in acute cardiogenic pulmonary edema by improving oxygenation and decreasing work of breathing.
A 65-year-old man with end-stage COPD presents with dyspnea and respiratory acidosis. He refuses intubation. What is the best next step?
A) Provide palliative care only
B) Offer noninvasive ventilation (BiPAP)
C) Administer IV corticosteroids
D) Increase oxygen to 100% FiO₂
Answer: B
Rationale: BiPAP is the best option for hypercapnic respiratory failure in a patient who refuses intubation.
A 50-year-old man is found unconscious. His ABG reveals pH 7.15, PaCO₂ 90 mmHg, and PaO₂ 60 mmHg. What is the best next step?
A) BiPAP
B) Endotracheal intubation
C) High-flow nasal oxygen
D) Nebulized bronchodilators
Answer: B
Rationale: Severe hypercapnia with respiratory acidosis and altered mental status requires immediate intubation.
Which of the following is a major cause of type 1 (hypoxemic) respiratory failure?
A) Myasthenia gravis
B) Neuromuscular blockade
C) ARDS
D) Opioid overdose
Answer: C
Rationale: ARDS causes severe V/Q mismatch and leads to type 1 respiratory failure.
Which intervention is most appropriate for preventing ventilator-associated pneumonia (VAP)?
A) Administer prophylactic antibiotics
B) Routine endotracheal suctioning
C) Elevate the head of the bed
D) Frequent deep sedation
.
Answer: C
Rationale: Elevating the head of the bed (>30 degrees) reduces the risk of aspiration and VAP
A 78-year-old woman with COPD is admitted for respiratory failure. She has been on 2 L of oxygen at home. ABG on 6 L of oxygen shows pH 7.29, PaCO₂ 65 mmHg, and PaO₂ 140 mmHg. What is the most likely cause of her worsening condition?
A) Oxygen-induced hypercapnia
B) Pulmonary embolism
C) Acute respiratory distress syndrome (ARDS)
D) Myasthenia gravis exacerbation
Answer: A
Rationale: In COPD, excessive oxygen can suppress hypoxic drive, leading to CO₂ retention and worsening hypercapnic respiratory failure.
Hypercapnia (PaCO₂ >50 mmHg), respiratory acidosis → Causes: COPD, opioid overdose, neuromuscular disorders
Type 2 respiratory failure →
Hypoxemia (PaO₂ <60 mmHg), normal or low PaCO₂ → Causes: ARDS, pneumonia, PE
Type 1 respiratory failure →
Prevents intubation in hypercapnic or hypoxemic failure
BiPAP for COPD and CHF exacerbations →
Intubation is for
respiratory acidosis with altered mental status
ARDS management
→ Low tidal volume ventilation (6 mL/kg), permissive hypercapnia, and high PEEP
Head of bed elevation, daily sedation breaks, early extubation when possible
VAP prevention →
High FiO₂ in COPD can suppress hypoxic drive and worsen hypercapnia
Oxygen-induced hypercapnia →
