ATI CRITICAL ALTERATIONS IN GAS EXCHANGE | ALL
PRACTICE Q&A 2026/2027 | A+ GRADED | EXAM PREP
|COMPREHENSIVE EXAM GUIDE 2026&2027
1. A client with acute dyspnea has an oxygen saturation of 86% on room air. Which action
should the nurse take first?
A. Obtain a sputum specimen
B. Place the client in high-Fowler's position ✔
C. Encourage oral fluid intake
D. Prepare the client for chest radiography
High-Fowler's positioning promotes maximal lung expansion and can immediately improve
ventilation. Airway and breathing interventions take priority when significant hypoxemia is
present.
2. Which finding is most concerning in a client experiencing an acute asthma exacerbation?
A. Expiratory wheezing
B. Productive cough
C. Inability to speak in full sentences ✔
D. Respiratory rate of 22/min
Inability to speak because of severe dyspnea indicates significant airflow obstruction and
respiratory compromise. This finding requires rapid intervention.
3. A nurse reviews a client's arterial blood gas results: pH 7.28, PaCO2 55 mm Hg, HCO3
24 mEq/L. How should these findings be interpreted?
A. Uncompensated respiratory acidosis ✔
B. Uncompensated metabolic acidosis
C. Compensated respiratory alkalosis
D. Compensated metabolic alkalosis
The low pH indicates acidosis, while the elevated PaCO2 identifies the respiratory cause. The
normal bicarbonate indicates that metabolic compensation has not occurred.
4. A client with COPD is receiving oxygen therapy. Which nursing action is most
appropriate?
A. Administer oxygen at the highest available flow rate
B. Maintain oxygen according to the prescribed target range ✔
C. Discontinue oxygen if the respiratory rate decreases
D. Restrict oxygen whenever carbon dioxide is elevated
,Clients with COPD require carefully titrated oxygen therapy. Excessive oxygen administration
can worsen hypercapnia in susceptible clients, so therapy should follow the prescribed target
saturation.
5. Which assessment finding indicates impaired oxygenation rather than impaired
ventilation?
A. Elevated PaCO2
B. Decreased respiratory rate
C. Decreased PaO2 ✔
D. Increased bicarbonate level
Oxygenation refers to oxygen entering the blood, reflected by PaO2 and oxygen saturation.
Ventilation primarily concerns movement of air and removal of carbon dioxide.
6. A client with pneumonia suddenly becomes restless and confused. The oxygen saturation
is 82%. Which action is the priority?
A. Encourage coughing
B. Increase oral fluids
C. Apply supplemental oxygen as prescribed ✔
D. Obtain a complete health history
Restlessness and confusion can be early manifestations of hypoxemia. Correcting impaired
oxygenation takes priority over obtaining additional history or promoting hydration.
7. Which arterial blood gas value represents normal arterial oxygenation?
A. PaO2 55 mm Hg
B. PaO2 80 mm Hg ✔
C. PaO2 45 mm Hg
D. PaO2 60 mm Hg
A typical arterial PaO2 range is approximately 80 to 100 mm Hg. Values below this range
indicate varying degrees of hypoxemia.
8. A client with COPD has thick respiratory secretions. Which intervention best promotes
secretion clearance?
A. Restrict fluids
B. Encourage adequate hydration if not contraindicated ✔
C. Keep the client on strict bed rest
D. Limit coughing to prevent fatigue
Adequate hydration helps thin respiratory secretions, making them easier to mobilize and
expectorate.
9. Which assessment finding is characteristic of hypoxemia?
A. Bradycardia
,B. Cyanosis ✔
C. Warm flushed skin
D. Increased urine output
Cyanosis can occur with significant oxygen desaturation. It is a late and concerning sign of
hypoxemia and should prompt immediate assessment and intervention.
10. A client with suspected pulmonary embolism reports sudden chest pain and shortness
of breath. Which additional finding should the nurse anticipate?
A. Sudden tachycardia ✔
B. Bilateral dependent edema only
C. Slow, shallow pulse
D. Severe bradycardia
Pulmonary embolism commonly causes sudden dyspnea, pleuritic chest pain, tachycardia,
tachypnea, and hypoxemia.
11. Which instruction should the nurse provide when teaching a client to use an incentive
spirometer?
A. Exhale forcefully into the device
B. Inhale slowly and deeply through the mouthpiece ✔
C. Use the device only when short of breath
D. Perform one breath every hour
The incentive spirometer encourages sustained maximal inspiration, helping prevent
atelectasis and promote alveolar expansion.
12. A postoperative client has shallow respirations and diminished breath sounds at the
lung bases. Which complication should the nurse suspect?
A. Atelectasis ✔
B. Pulmonary embolism
C. Tension pneumothorax
D. Pulmonary edema
Atelectasis commonly develops after surgery because of shallow breathing, pain, and reduced
mobility. Diminished basilar breath sounds are common findings.
13. Which position is generally most beneficial for a client experiencing severe dyspnea?
A. Supine
B. Trendelenburg
C. High-Fowler's ✔
D. Prone with the head flat
High-Fowler's positioning maximizes diaphragmatic expansion and decreases abdominal
pressure against the diaphragm, improving ventilation.
, 14. A client with respiratory distress has an oxygen saturation of 78% despite oxygen
therapy. Which action should the nurse take?
A. Reassess after 30 minutes
B. Notify the provider or activate emergency assistance immediately ✔
C. Encourage the client to sleep
D. Document the finding as expected
Persistent severe hypoxemia despite oxygen therapy indicates potentially life-threatening
respiratory failure and requires immediate escalation.
15. Which finding is most consistent with respiratory alkalosis?
A. pH 7.50 and PaCO2 30 mm Hg ✔
B. pH 7.28 and PaCO2 55 mm Hg
C. pH 7.30 and HCO3 18 mEq/L
D. pH 7.48 and HCO3 32 mEq/L
Respiratory alkalosis is characterized by an elevated pH with a decreased PaCO2, usually
resulting from excessive alveolar ventilation.
16. A client with emphysema demonstrates pursed-lip breathing. What is the primary
benefit of this technique?
A. Increases airway collapse
B. Promotes prolonged exhalation and reduces air trapping ✔
C. Eliminates the need for oxygen therapy
D. Increases respiratory secretions
Pursed-lip breathing creates mild positive pressure during exhalation, helping keep small
airways open and reduce air trapping.
17. Which finding in a client with pneumonia requires immediate intervention?
A. Temperature of 38.2°C
B. Productive cough
C. Oxygen saturation of 84% ✔
D. Fatigue with activity
An oxygen saturation of 84% represents significant hypoxemia and is a priority over expected
manifestations such as fever, cough, and fatigue.
18. A nurse is caring for a client with a chest tube connected to a water-seal drainage
system. Which finding is expected?
A. Continuous vigorous bubbling in the water-seal chamber
B. Tidaling of the water level with respirations ✔
C. No drainage at any time
D. Clamping the tube routinely every hour
PRACTICE Q&A 2026/2027 | A+ GRADED | EXAM PREP
|COMPREHENSIVE EXAM GUIDE 2026&2027
1. A client with acute dyspnea has an oxygen saturation of 86% on room air. Which action
should the nurse take first?
A. Obtain a sputum specimen
B. Place the client in high-Fowler's position ✔
C. Encourage oral fluid intake
D. Prepare the client for chest radiography
High-Fowler's positioning promotes maximal lung expansion and can immediately improve
ventilation. Airway and breathing interventions take priority when significant hypoxemia is
present.
2. Which finding is most concerning in a client experiencing an acute asthma exacerbation?
A. Expiratory wheezing
B. Productive cough
C. Inability to speak in full sentences ✔
D. Respiratory rate of 22/min
Inability to speak because of severe dyspnea indicates significant airflow obstruction and
respiratory compromise. This finding requires rapid intervention.
3. A nurse reviews a client's arterial blood gas results: pH 7.28, PaCO2 55 mm Hg, HCO3
24 mEq/L. How should these findings be interpreted?
A. Uncompensated respiratory acidosis ✔
B. Uncompensated metabolic acidosis
C. Compensated respiratory alkalosis
D. Compensated metabolic alkalosis
The low pH indicates acidosis, while the elevated PaCO2 identifies the respiratory cause. The
normal bicarbonate indicates that metabolic compensation has not occurred.
4. A client with COPD is receiving oxygen therapy. Which nursing action is most
appropriate?
A. Administer oxygen at the highest available flow rate
B. Maintain oxygen according to the prescribed target range ✔
C. Discontinue oxygen if the respiratory rate decreases
D. Restrict oxygen whenever carbon dioxide is elevated
,Clients with COPD require carefully titrated oxygen therapy. Excessive oxygen administration
can worsen hypercapnia in susceptible clients, so therapy should follow the prescribed target
saturation.
5. Which assessment finding indicates impaired oxygenation rather than impaired
ventilation?
A. Elevated PaCO2
B. Decreased respiratory rate
C. Decreased PaO2 ✔
D. Increased bicarbonate level
Oxygenation refers to oxygen entering the blood, reflected by PaO2 and oxygen saturation.
Ventilation primarily concerns movement of air and removal of carbon dioxide.
6. A client with pneumonia suddenly becomes restless and confused. The oxygen saturation
is 82%. Which action is the priority?
A. Encourage coughing
B. Increase oral fluids
C. Apply supplemental oxygen as prescribed ✔
D. Obtain a complete health history
Restlessness and confusion can be early manifestations of hypoxemia. Correcting impaired
oxygenation takes priority over obtaining additional history or promoting hydration.
7. Which arterial blood gas value represents normal arterial oxygenation?
A. PaO2 55 mm Hg
B. PaO2 80 mm Hg ✔
C. PaO2 45 mm Hg
D. PaO2 60 mm Hg
A typical arterial PaO2 range is approximately 80 to 100 mm Hg. Values below this range
indicate varying degrees of hypoxemia.
8. A client with COPD has thick respiratory secretions. Which intervention best promotes
secretion clearance?
A. Restrict fluids
B. Encourage adequate hydration if not contraindicated ✔
C. Keep the client on strict bed rest
D. Limit coughing to prevent fatigue
Adequate hydration helps thin respiratory secretions, making them easier to mobilize and
expectorate.
9. Which assessment finding is characteristic of hypoxemia?
A. Bradycardia
,B. Cyanosis ✔
C. Warm flushed skin
D. Increased urine output
Cyanosis can occur with significant oxygen desaturation. It is a late and concerning sign of
hypoxemia and should prompt immediate assessment and intervention.
10. A client with suspected pulmonary embolism reports sudden chest pain and shortness
of breath. Which additional finding should the nurse anticipate?
A. Sudden tachycardia ✔
B. Bilateral dependent edema only
C. Slow, shallow pulse
D. Severe bradycardia
Pulmonary embolism commonly causes sudden dyspnea, pleuritic chest pain, tachycardia,
tachypnea, and hypoxemia.
11. Which instruction should the nurse provide when teaching a client to use an incentive
spirometer?
A. Exhale forcefully into the device
B. Inhale slowly and deeply through the mouthpiece ✔
C. Use the device only when short of breath
D. Perform one breath every hour
The incentive spirometer encourages sustained maximal inspiration, helping prevent
atelectasis and promote alveolar expansion.
12. A postoperative client has shallow respirations and diminished breath sounds at the
lung bases. Which complication should the nurse suspect?
A. Atelectasis ✔
B. Pulmonary embolism
C. Tension pneumothorax
D. Pulmonary edema
Atelectasis commonly develops after surgery because of shallow breathing, pain, and reduced
mobility. Diminished basilar breath sounds are common findings.
13. Which position is generally most beneficial for a client experiencing severe dyspnea?
A. Supine
B. Trendelenburg
C. High-Fowler's ✔
D. Prone with the head flat
High-Fowler's positioning maximizes diaphragmatic expansion and decreases abdominal
pressure against the diaphragm, improving ventilation.
, 14. A client with respiratory distress has an oxygen saturation of 78% despite oxygen
therapy. Which action should the nurse take?
A. Reassess after 30 minutes
B. Notify the provider or activate emergency assistance immediately ✔
C. Encourage the client to sleep
D. Document the finding as expected
Persistent severe hypoxemia despite oxygen therapy indicates potentially life-threatening
respiratory failure and requires immediate escalation.
15. Which finding is most consistent with respiratory alkalosis?
A. pH 7.50 and PaCO2 30 mm Hg ✔
B. pH 7.28 and PaCO2 55 mm Hg
C. pH 7.30 and HCO3 18 mEq/L
D. pH 7.48 and HCO3 32 mEq/L
Respiratory alkalosis is characterized by an elevated pH with a decreased PaCO2, usually
resulting from excessive alveolar ventilation.
16. A client with emphysema demonstrates pursed-lip breathing. What is the primary
benefit of this technique?
A. Increases airway collapse
B. Promotes prolonged exhalation and reduces air trapping ✔
C. Eliminates the need for oxygen therapy
D. Increases respiratory secretions
Pursed-lip breathing creates mild positive pressure during exhalation, helping keep small
airways open and reduce air trapping.
17. Which finding in a client with pneumonia requires immediate intervention?
A. Temperature of 38.2°C
B. Productive cough
C. Oxygen saturation of 84% ✔
D. Fatigue with activity
An oxygen saturation of 84% represents significant hypoxemia and is a priority over expected
manifestations such as fever, cough, and fatigue.
18. A nurse is caring for a client with a chest tube connected to a water-seal drainage
system. Which finding is expected?
A. Continuous vigorous bubbling in the water-seal chamber
B. Tidaling of the water level with respirations ✔
C. No drainage at any time
D. Clamping the tube routinely every hour
