ATI CRITICAL ALTERATIONS IN GAS
EXCHANGE: COMPREHENSIVE EXAM
QUESTIONS AND CORRECT ANSWERS
(VERIFIED ANSWERS) PLUS
RATIONALES 2026 Q&A | INSTANT
DOWNLOAD PDF.
Core Domains
1. Respiratory Assessment and Diagnostic Testing
2. Oxygen Therapy and Delivery Systems
3. Airway Management and Suctioning
4. Mechanical Ventilation
5. Acute Respiratory Failure and ARDS
6. Obstructive Pulmonary Disorders
7. Restrictive Pulmonary Disorders and Pneumothorax
8. Pulmonary Embolism and Pulmonary Hypertension
9. Infectious Respiratory Disorders
10. Acid-Base Balance and ABG Interpretation
Introduction
The ATI Critical Alterations in Gas Exchange Examination
assesses the nurse's ability to recognize and manage life-
threatening respiratory conditions across the lifespan. It
evaluates respiratory assessment, oxygen delivery, airway
management, mechanical ventilation, and interpretation of
arterial blood gases. Candidates must apply clinical judgment to
scenarios involving acute respiratory failure, ARDS, COPD,
asthma, pulmonary embolism, pneumothorax, and infectious
processes. Emphasis is placed on prioritization, safe intervention,
,and evaluation of outcomes. Multiple-choice and scenario-based
items require synthesis of foundational theory, applied
professional knowledge, and real-world decision-making to ensure
safe, evidence-based nursing care for clients experiencing critical
gas exchange alterations.
Section One: Questions 1–100
1. A nurse is assessing a client with a suspected
pulmonary embolism. Which finding is most consistent
with this condition?
A. Bradycardia and hypertension
B. Sudden onset of dyspnea and pleuritic chest pain
C. Productive cough with green sputum
D. Gradual onset of fever and chills
Correct answer: B
RATIONALE: Pulmonary embolism typically presents with
sudden dyspnea, pleuritic chest pain, tachycardia, and
hypoxemia. Bradycardia, hypertension, and productive cough are
not typical.
2. A client with COPD has an oxygen saturation of 85% on
room air. Which oxygen delivery method is most
appropriate?
A. Non-rebreather mask at 15 L/min
B. Nasal cannula at 1–2 L/min titrated to 88–92%
C. Simple face mask at 8 L/min
D. Venturi mask at 40%
Correct answer: B
, RATIONALE: Clients with COPD may retain CO₂ and rely on
hypoxic drive. Low-flow oxygen via nasal cannula at 1–2 L/min
titrated to an SpO₂ of 88–92% is safest.
3. A client is admitted with acute respiratory failure. Which
arterial blood gas value indicates respiratory acidosis?
A. pH 7.48, PaCO₂ 30 mm Hg
B. pH 7.30, PaCO₂ 55 mm Hg
C. pH 7.50, PaCO₂ 40 mm Hg
D. pH 7.35, PaCO₂ 45 mm Hg
Correct answer: B
RATIONALE: Respiratory acidosis is characterized by a pH
below 7.35 and a PaCO₂ above 45 mm Hg due to hypoventilation.
4. A nurse is caring for a client with a chest tube. Which
finding indicates an air leak?
A. Intermittent bubbling in the suction control chamber
B. Fluctuation in the water seal chamber with respiration
C. Continuous bubbling in the water seal chamber
D. No drainage in the collection chamber
Correct answer: C
RATIONALE: Continuous bubbling in the water seal chamber
indicates an air leak. Intermittent bubbling with expiration may
be normal, and fluctuation is expected.
5. A client with ARDS is being mechanically ventilated.
Which ventilator setting should the nurse anticipate to
improve oxygenation?
A. Low PEEP
B. High tidal volume
, C. Increased PEEP
D. Decreased respiratory rate
Correct answer: C
RATIONALE: Positive end-expiratory pressure (PEEP) is
increased in ARDS to recruit collapsed alveoli and improve
oxygenation. High tidal volumes can cause further lung injury.
6. A nurse is preparing to suction a client with a
tracheostomy. Which action should the nurse take first?
A. Instill 5 mL of normal saline into the tracheostomy
B. Hyperoxygenate the client with 100% oxygen
C. Suction for 30 seconds
D. Apply suction while inserting the catheter
Correct answer: B
RATIONALE: Hyperoxygenation before suctioning prevents
hypoxemia. Saline instillation is not routinely recommended, and
suction should be applied only during withdrawal for no more
than 10–15 seconds.
7. A client with pneumonia has a respiratory rate of 32,
oxygen saturation of 88%, and is using accessory muscles.
Which action should the nurse take first?
A. Administer prescribed antibiotics
B. Obtain a sputum culture
C. Apply oxygen and position for comfort
D. Encourage oral fluids
Correct answer: C
RATIONALE: The client is in respiratory distress with
hypoxemia. Applying oxygen and positioning to maximize
EXCHANGE: COMPREHENSIVE EXAM
QUESTIONS AND CORRECT ANSWERS
(VERIFIED ANSWERS) PLUS
RATIONALES 2026 Q&A | INSTANT
DOWNLOAD PDF.
Core Domains
1. Respiratory Assessment and Diagnostic Testing
2. Oxygen Therapy and Delivery Systems
3. Airway Management and Suctioning
4. Mechanical Ventilation
5. Acute Respiratory Failure and ARDS
6. Obstructive Pulmonary Disorders
7. Restrictive Pulmonary Disorders and Pneumothorax
8. Pulmonary Embolism and Pulmonary Hypertension
9. Infectious Respiratory Disorders
10. Acid-Base Balance and ABG Interpretation
Introduction
The ATI Critical Alterations in Gas Exchange Examination
assesses the nurse's ability to recognize and manage life-
threatening respiratory conditions across the lifespan. It
evaluates respiratory assessment, oxygen delivery, airway
management, mechanical ventilation, and interpretation of
arterial blood gases. Candidates must apply clinical judgment to
scenarios involving acute respiratory failure, ARDS, COPD,
asthma, pulmonary embolism, pneumothorax, and infectious
processes. Emphasis is placed on prioritization, safe intervention,
,and evaluation of outcomes. Multiple-choice and scenario-based
items require synthesis of foundational theory, applied
professional knowledge, and real-world decision-making to ensure
safe, evidence-based nursing care for clients experiencing critical
gas exchange alterations.
Section One: Questions 1–100
1. A nurse is assessing a client with a suspected
pulmonary embolism. Which finding is most consistent
with this condition?
A. Bradycardia and hypertension
B. Sudden onset of dyspnea and pleuritic chest pain
C. Productive cough with green sputum
D. Gradual onset of fever and chills
Correct answer: B
RATIONALE: Pulmonary embolism typically presents with
sudden dyspnea, pleuritic chest pain, tachycardia, and
hypoxemia. Bradycardia, hypertension, and productive cough are
not typical.
2. A client with COPD has an oxygen saturation of 85% on
room air. Which oxygen delivery method is most
appropriate?
A. Non-rebreather mask at 15 L/min
B. Nasal cannula at 1–2 L/min titrated to 88–92%
C. Simple face mask at 8 L/min
D. Venturi mask at 40%
Correct answer: B
, RATIONALE: Clients with COPD may retain CO₂ and rely on
hypoxic drive. Low-flow oxygen via nasal cannula at 1–2 L/min
titrated to an SpO₂ of 88–92% is safest.
3. A client is admitted with acute respiratory failure. Which
arterial blood gas value indicates respiratory acidosis?
A. pH 7.48, PaCO₂ 30 mm Hg
B. pH 7.30, PaCO₂ 55 mm Hg
C. pH 7.50, PaCO₂ 40 mm Hg
D. pH 7.35, PaCO₂ 45 mm Hg
Correct answer: B
RATIONALE: Respiratory acidosis is characterized by a pH
below 7.35 and a PaCO₂ above 45 mm Hg due to hypoventilation.
4. A nurse is caring for a client with a chest tube. Which
finding indicates an air leak?
A. Intermittent bubbling in the suction control chamber
B. Fluctuation in the water seal chamber with respiration
C. Continuous bubbling in the water seal chamber
D. No drainage in the collection chamber
Correct answer: C
RATIONALE: Continuous bubbling in the water seal chamber
indicates an air leak. Intermittent bubbling with expiration may
be normal, and fluctuation is expected.
5. A client with ARDS is being mechanically ventilated.
Which ventilator setting should the nurse anticipate to
improve oxygenation?
A. Low PEEP
B. High tidal volume
, C. Increased PEEP
D. Decreased respiratory rate
Correct answer: C
RATIONALE: Positive end-expiratory pressure (PEEP) is
increased in ARDS to recruit collapsed alveoli and improve
oxygenation. High tidal volumes can cause further lung injury.
6. A nurse is preparing to suction a client with a
tracheostomy. Which action should the nurse take first?
A. Instill 5 mL of normal saline into the tracheostomy
B. Hyperoxygenate the client with 100% oxygen
C. Suction for 30 seconds
D. Apply suction while inserting the catheter
Correct answer: B
RATIONALE: Hyperoxygenation before suctioning prevents
hypoxemia. Saline instillation is not routinely recommended, and
suction should be applied only during withdrawal for no more
than 10–15 seconds.
7. A client with pneumonia has a respiratory rate of 32,
oxygen saturation of 88%, and is using accessory muscles.
Which action should the nurse take first?
A. Administer prescribed antibiotics
B. Obtain a sputum culture
C. Apply oxygen and position for comfort
D. Encourage oral fluids
Correct answer: C
RATIONALE: The client is in respiratory distress with
hypoxemia. Applying oxygen and positioning to maximize
