NBRC CRT – Certified Respiratory Therapist
Exam Questions and Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf
1. A patient with acute dyspnea has an oxygen saturation of 84% on
room air. Which intervention should the respiratory therapist
perform first?
a. Obtain a sputum culture
b. Initiate appropriate supplemental oxygen
c. Perform a complete pulmonary function test
d. Encourage oral fluid intake
Answer: b. Initiate appropriate supplemental oxygen
Rationale: An SpO₂ of 84% indicates significant hypoxemia. The
immediate priority is to improve oxygenation while continuing
assessment and identifying the underlying cause. Diagnostic procedures
,such as sputum collection or pulmonary function testing should not
delay correction of potentially dangerous hypoxemia.
2. Which arterial blood gas (ABG) value is within the normal adult
range?
a. pH 7.25
b. PaCO₂ 50 mm Hg
c. PaO₂ 60 mm Hg
d. pH 7.40
Answer: d. pH 7.40
Rationale: Normal arterial pH is approximately 7.35–7.45. A PaCO₂ of
about 35–45 mm Hg and PaO₂ generally around 80–100 mm Hg are
expected in a healthy adult breathing room air at sea level. A pH of 7.40
is therefore normal.
3. A patient has the following ABG results: pH 7.28, PaCO₂ 55 mm
Hg, HCO₃⁻ 24 mEq/L. How should these results be interpreted?
a. Uncompensated respiratory acidosis
b. Compensated respiratory acidosis
,c. Uncompensated metabolic acidosis
d. Respiratory alkalosis
Answer: a. Uncompensated respiratory acidosis
Rationale: The pH is below 7.35, indicating acidemia. The PaCO₂ is
elevated, identifying a respiratory cause. The bicarbonate is within the
normal range, indicating that significant metabolic compensation has
not occurred. Therefore, this represents uncompensated respiratory
acidosis.
4. Which oxygen delivery device provides the most precise and
controlled FiO₂ for a spontaneously breathing patient?
a. Nasal cannula
b. Simple mask
c. Venturi mask
d. Nonrebreathing mask
Answer: c. Venturi mask
Rationale: A Venturi mask uses the air-entrainment principle to deliver a
relatively fixed and controlled oxygen concentration. This makes it
particularly useful when precise FiO₂ control is important, such as in
patients at risk for CO₂ retention.
, 5. What is the primary purpose of humidification during oxygen
therapy?
a. Increase blood pressure
b. Prevent airway drying and irritation
c. Decrease metabolic rate
d. Reduce pulmonary blood flow
Answer: b. Prevent airway drying and irritation
Rationale: Supplemental oxygen, particularly when delivered at higher
flows, can dry the airway mucosa. Humidification adds moisture to the
inspired gas and helps maintain mucociliary function, reduce
discomfort, and prevent excessive drying of respiratory secretions.
6. A patient with COPD is receiving oxygen through a Venturi mask.
The patient's SpO₂ is 86%. What should the respiratory therapist
do first?
a. Immediately discontinue oxygen
b. Assess the patient and verify the oxygen delivery system
c. Administer a sedative
d. Place the patient on room air
Exam Questions and Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf
1. A patient with acute dyspnea has an oxygen saturation of 84% on
room air. Which intervention should the respiratory therapist
perform first?
a. Obtain a sputum culture
b. Initiate appropriate supplemental oxygen
c. Perform a complete pulmonary function test
d. Encourage oral fluid intake
Answer: b. Initiate appropriate supplemental oxygen
Rationale: An SpO₂ of 84% indicates significant hypoxemia. The
immediate priority is to improve oxygenation while continuing
assessment and identifying the underlying cause. Diagnostic procedures
,such as sputum collection or pulmonary function testing should not
delay correction of potentially dangerous hypoxemia.
2. Which arterial blood gas (ABG) value is within the normal adult
range?
a. pH 7.25
b. PaCO₂ 50 mm Hg
c. PaO₂ 60 mm Hg
d. pH 7.40
Answer: d. pH 7.40
Rationale: Normal arterial pH is approximately 7.35–7.45. A PaCO₂ of
about 35–45 mm Hg and PaO₂ generally around 80–100 mm Hg are
expected in a healthy adult breathing room air at sea level. A pH of 7.40
is therefore normal.
3. A patient has the following ABG results: pH 7.28, PaCO₂ 55 mm
Hg, HCO₃⁻ 24 mEq/L. How should these results be interpreted?
a. Uncompensated respiratory acidosis
b. Compensated respiratory acidosis
,c. Uncompensated metabolic acidosis
d. Respiratory alkalosis
Answer: a. Uncompensated respiratory acidosis
Rationale: The pH is below 7.35, indicating acidemia. The PaCO₂ is
elevated, identifying a respiratory cause. The bicarbonate is within the
normal range, indicating that significant metabolic compensation has
not occurred. Therefore, this represents uncompensated respiratory
acidosis.
4. Which oxygen delivery device provides the most precise and
controlled FiO₂ for a spontaneously breathing patient?
a. Nasal cannula
b. Simple mask
c. Venturi mask
d. Nonrebreathing mask
Answer: c. Venturi mask
Rationale: A Venturi mask uses the air-entrainment principle to deliver a
relatively fixed and controlled oxygen concentration. This makes it
particularly useful when precise FiO₂ control is important, such as in
patients at risk for CO₂ retention.
, 5. What is the primary purpose of humidification during oxygen
therapy?
a. Increase blood pressure
b. Prevent airway drying and irritation
c. Decrease metabolic rate
d. Reduce pulmonary blood flow
Answer: b. Prevent airway drying and irritation
Rationale: Supplemental oxygen, particularly when delivered at higher
flows, can dry the airway mucosa. Humidification adds moisture to the
inspired gas and helps maintain mucociliary function, reduce
discomfort, and prevent excessive drying of respiratory secretions.
6. A patient with COPD is receiving oxygen through a Venturi mask.
The patient's SpO₂ is 86%. What should the respiratory therapist
do first?
a. Immediately discontinue oxygen
b. Assess the patient and verify the oxygen delivery system
c. Administer a sedative
d. Place the patient on room air
