NBRC TMC-CRT RRT EXAM 300
ACTUAL QUESTIONS AND CORRECT
ANSWERS WITH RATIONALE LATEST
UPDATE ALREADY GRADED A+
This comprehensive collection of 300 unique multiple-choice questions
is specifically designed to prepare candidates for the NBRC TMC, CRT,
and RRT credentialing exams. The questions are organized into fifteen
sections covering patient data evaluation, arterial blood gas
interpretation, mechanical ventilation, airway management,
pharmacology, equipment troubleshooting, emergency procedures, and
critical care concepts. Each question includes a correct answer and a
detailed rationale explaining the clinical reasoning, reinforcing key
respiratory therapy principles, and clarifying common misconceptions.
This structured approach promotes active learning, deepens
understanding of both entry-level and advanced respiratory care
concepts, and prepares candidates to successfully achieve the high cut
score required for RRT eligibility and clinical practice excellence.
Section 1: Patient Data Evaluation and Clinical Assessment
Question 1: A patient's arterial blood gas results show a pH of 7.32, PaCO2 of 50
mmHg, and HCO3 of 24 mEq/L. What is the most appropriate interpretation?
A) Metabolic acidosis
B) Metabolic alkalosis
C) Respiratory acidosis
,D) Respiratory alkalosis
Correct Answer: C
Rationale: The pH is below normal (7.35-7.45), indicating acidosis. The PaCO2 is
elevated above normal (35-45 mmHg), indicating respiratory retention. The HCO3
is normal, meaning no compensation has occurred. This pattern is consistent with
acute respiratory acidosis.
Question 2: A respiratory therapist is asked to recommend a diagnostic procedure
for a patient with suspected pulmonary embolism. Which test is considered the
gold standard for diagnosis?
A) Chest X-ray
B) D-dimer blood test
C) CT pulmonary angiography
D) Ventilation-perfusion scan
Correct Answer: C
Rationale: CT pulmonary angiography is the gold standard for diagnosing
pulmonary embolism. It provides high-resolution imaging of the pulmonary
vasculature. A D-dimer is a screening test, and a V/Q scan may be used when CT
is contraindicated.
Question 3: A patient with a history of COPD has a PaO2 of 55 mmHg and a
PaCO2 of 52 mmHg on room air. Which intervention should the respiratory
therapist recommend initially?
A) Intubation and mechanical ventilation
B) Noninvasive positive pressure ventilation
C) Low-flow oxygen therapy
D) High-flow nasal cannula at 15 L/min
Correct Answer: C
Rationale: Low-flow oxygen therapy should be initiated with caution in COPD
patients to avoid suppressing the hypoxic drive. The goal is to maintain SpO2
between 88-92% while monitoring for worsening hypercapnia.
Question 4: Which of the following parameters is most useful for differentiating
obstructive lung disease from restrictive lung disease?
A) Total lung capacity
B) Forced vital capacity
C) FEV1/FVC ratio
D) Residual volume
Correct Answer: C
,Rationale: The FEV1/FVC ratio is the primary differentiator. In obstructive
disease, the ratio is decreased (< 0.70). In restrictive disease, both FEV1 and FVC
are proportionally decreased, so the ratio is normal or increased.
Question 5: A patient is experiencing cardiac arrhythmias and muscle weakness.
An arterial blood gas indicates metabolic alkalosis. Which lab value should the
therapist assess next?
A) White blood cell count
B) Blood urea nitrogen
C) Plasma protein
D) Potassium level
Correct Answer: D
Rationale: Metabolic alkalosis is often associated with hypokalemia. Potassium
shifts intracellularly in exchange for hydrogen ions, leading to muscle weakness,
arrhythmias, and other complications.
Question 6: What is the normal range for central venous pressure in a healthy
adult?
A) 0 to 5 mmHg
B) 2 to 6 mmHg
C) 8 to 12 mmHg
D) 15 to 20 mmHg
Correct Answer: B
Rationale: Normal CVP is 2 to 6 mmHg, reflecting right ventricular preload and
venous return. Values above 6 mmHg suggest volume overload or right ventricular
dysfunction.
Question 7: A patient has a hemoglobin level of 10 g/dL and an SaO2 of 90%.
Using the formula CaO2 = (Hb × 1.34 × SaO2) + (0.003 × PaO2), with a PaO2 of
60 mmHg, what is the approximate arterial oxygen content?
A) 10 mL/dL
B) 12 mL/dL
C) 14 mL/dL
D) 16 mL/dL
Correct Answer: B
Rationale: CaO2 = (10 × 1.34 × 0.90) + (0.003 × 60) = 12.06 + 0.18 = 12.24
mL/dL. This value is significantly reduced from normal, indicating hypoxemia due
to low hemoglobin and desaturation.
, Question 8: A respiratory therapist is preparing to perform a 6-minute walk test.
Which of the following is a contraindication to performing this test?
A) Oxygen saturation of 89% on room air
B) Unstable angina or recent myocardial infarction
C) Heart rate of 100 beats per minute
D) Blood pressure of 140/90 mmHg
Correct Answer: B
Rationale: Unstable angina or recent myocardial infarction is an absolute
contraindication due to the risk of cardiac events. Other findings require
monitoring but are not absolute contraindications.
Question 9: What does a chest radiograph showing bilateral fluffy infiltrates in a
patient with severe dyspnea most likely indicate?
A) Pneumothorax
B) Pleural effusion
C) Pulmonary edema
D) Atelectasis
Correct Answer: C
Rationale: Bilateral fluffy infiltrates are characteristic of pulmonary edema, often
due to heart failure. A pneumothorax shows a pleural line, pleural effusion appears
as blunting of costophrenic angles, and atelectasis appears as linear opacities.
Question 10: The respiratory therapist is assessing a patient who has difficulty
breathing while lying flat. What is the correct term for this condition?
A) Orthopnea
B) Hypopnea
C) Eupnea
D) Bradypnea
Correct Answer: A
Rationale: Orthopnea is dyspnea that occurs when lying flat and is relieved by
sitting up. It is commonly seen in heart failure. Hypopnea is shallow breathing,
eupnea is normal breathing, and bradypnea is slow breathing.
Question 11: Which pulmonary function test parameter is measured during a
forced vital capacity maneuver?
A) Total lung capacity
B) Functional residual capacity
C) FEV1 and FVC
D) Diffusion capacity
Correct Answer: C
ACTUAL QUESTIONS AND CORRECT
ANSWERS WITH RATIONALE LATEST
UPDATE ALREADY GRADED A+
This comprehensive collection of 300 unique multiple-choice questions
is specifically designed to prepare candidates for the NBRC TMC, CRT,
and RRT credentialing exams. The questions are organized into fifteen
sections covering patient data evaluation, arterial blood gas
interpretation, mechanical ventilation, airway management,
pharmacology, equipment troubleshooting, emergency procedures, and
critical care concepts. Each question includes a correct answer and a
detailed rationale explaining the clinical reasoning, reinforcing key
respiratory therapy principles, and clarifying common misconceptions.
This structured approach promotes active learning, deepens
understanding of both entry-level and advanced respiratory care
concepts, and prepares candidates to successfully achieve the high cut
score required for RRT eligibility and clinical practice excellence.
Section 1: Patient Data Evaluation and Clinical Assessment
Question 1: A patient's arterial blood gas results show a pH of 7.32, PaCO2 of 50
mmHg, and HCO3 of 24 mEq/L. What is the most appropriate interpretation?
A) Metabolic acidosis
B) Metabolic alkalosis
C) Respiratory acidosis
,D) Respiratory alkalosis
Correct Answer: C
Rationale: The pH is below normal (7.35-7.45), indicating acidosis. The PaCO2 is
elevated above normal (35-45 mmHg), indicating respiratory retention. The HCO3
is normal, meaning no compensation has occurred. This pattern is consistent with
acute respiratory acidosis.
Question 2: A respiratory therapist is asked to recommend a diagnostic procedure
for a patient with suspected pulmonary embolism. Which test is considered the
gold standard for diagnosis?
A) Chest X-ray
B) D-dimer blood test
C) CT pulmonary angiography
D) Ventilation-perfusion scan
Correct Answer: C
Rationale: CT pulmonary angiography is the gold standard for diagnosing
pulmonary embolism. It provides high-resolution imaging of the pulmonary
vasculature. A D-dimer is a screening test, and a V/Q scan may be used when CT
is contraindicated.
Question 3: A patient with a history of COPD has a PaO2 of 55 mmHg and a
PaCO2 of 52 mmHg on room air. Which intervention should the respiratory
therapist recommend initially?
A) Intubation and mechanical ventilation
B) Noninvasive positive pressure ventilation
C) Low-flow oxygen therapy
D) High-flow nasal cannula at 15 L/min
Correct Answer: C
Rationale: Low-flow oxygen therapy should be initiated with caution in COPD
patients to avoid suppressing the hypoxic drive. The goal is to maintain SpO2
between 88-92% while monitoring for worsening hypercapnia.
Question 4: Which of the following parameters is most useful for differentiating
obstructive lung disease from restrictive lung disease?
A) Total lung capacity
B) Forced vital capacity
C) FEV1/FVC ratio
D) Residual volume
Correct Answer: C
,Rationale: The FEV1/FVC ratio is the primary differentiator. In obstructive
disease, the ratio is decreased (< 0.70). In restrictive disease, both FEV1 and FVC
are proportionally decreased, so the ratio is normal or increased.
Question 5: A patient is experiencing cardiac arrhythmias and muscle weakness.
An arterial blood gas indicates metabolic alkalosis. Which lab value should the
therapist assess next?
A) White blood cell count
B) Blood urea nitrogen
C) Plasma protein
D) Potassium level
Correct Answer: D
Rationale: Metabolic alkalosis is often associated with hypokalemia. Potassium
shifts intracellularly in exchange for hydrogen ions, leading to muscle weakness,
arrhythmias, and other complications.
Question 6: What is the normal range for central venous pressure in a healthy
adult?
A) 0 to 5 mmHg
B) 2 to 6 mmHg
C) 8 to 12 mmHg
D) 15 to 20 mmHg
Correct Answer: B
Rationale: Normal CVP is 2 to 6 mmHg, reflecting right ventricular preload and
venous return. Values above 6 mmHg suggest volume overload or right ventricular
dysfunction.
Question 7: A patient has a hemoglobin level of 10 g/dL and an SaO2 of 90%.
Using the formula CaO2 = (Hb × 1.34 × SaO2) + (0.003 × PaO2), with a PaO2 of
60 mmHg, what is the approximate arterial oxygen content?
A) 10 mL/dL
B) 12 mL/dL
C) 14 mL/dL
D) 16 mL/dL
Correct Answer: B
Rationale: CaO2 = (10 × 1.34 × 0.90) + (0.003 × 60) = 12.06 + 0.18 = 12.24
mL/dL. This value is significantly reduced from normal, indicating hypoxemia due
to low hemoglobin and desaturation.
, Question 8: A respiratory therapist is preparing to perform a 6-minute walk test.
Which of the following is a contraindication to performing this test?
A) Oxygen saturation of 89% on room air
B) Unstable angina or recent myocardial infarction
C) Heart rate of 100 beats per minute
D) Blood pressure of 140/90 mmHg
Correct Answer: B
Rationale: Unstable angina or recent myocardial infarction is an absolute
contraindication due to the risk of cardiac events. Other findings require
monitoring but are not absolute contraindications.
Question 9: What does a chest radiograph showing bilateral fluffy infiltrates in a
patient with severe dyspnea most likely indicate?
A) Pneumothorax
B) Pleural effusion
C) Pulmonary edema
D) Atelectasis
Correct Answer: C
Rationale: Bilateral fluffy infiltrates are characteristic of pulmonary edema, often
due to heart failure. A pneumothorax shows a pleural line, pleural effusion appears
as blunting of costophrenic angles, and atelectasis appears as linear opacities.
Question 10: The respiratory therapist is assessing a patient who has difficulty
breathing while lying flat. What is the correct term for this condition?
A) Orthopnea
B) Hypopnea
C) Eupnea
D) Bradypnea
Correct Answer: A
Rationale: Orthopnea is dyspnea that occurs when lying flat and is relieved by
sitting up. It is commonly seen in heart failure. Hypopnea is shallow breathing,
eupnea is normal breathing, and bradypnea is slow breathing.
Question 11: Which pulmonary function test parameter is measured during a
forced vital capacity maneuver?
A) Total lung capacity
B) Functional residual capacity
C) FEV1 and FVC
D) Diffusion capacity
Correct Answer: C
