NBRC TMC Board Review Exam Questions and Verified
Answers with Rationale | Latest Edition 2026/2027
Question 1
A 55-year-old male with a history of severe chronic obstructive
pulmonary disease is admitted with acute shortness of breath and
peripheral edema. Arterial blood gas analysis on room air reveals pH
7.33, PaCO2 60 mm Hg, PaO2 54 mm Hg, and HCO3 32 mEq/L. Which
of the following oxygen delivery devices is most appropriate to initiate
controlled oxygen therapy?
A. Non-rebreathing mask at 15 liters per minute
B. Simple face mask at 10 liters per minute
C. Venturi mask delivering 24 percent oxygen
D. Nasal cannula at 6 liters per minute
Correct Answer: C
Rationale: Patients with chronic hypercapnia and acute on chronic
respiratory failure require precise, controlled low-flow oxygen
administration to prevent the removal of their hypoxic respiratory drive.
A Venturi mask delivers a fixed and exact fraction of inspired oxygen,
making it the safest option to avoid precipitating severe hypoventilation
in chronic obstructive pulmonary disease exacerbations.
Question 2
During a routine ventilator check in the intensive care unit, the
respiratory therapist performs a manual circuit leak test and observes a
significant difference between the set tidal volume and the exhaled tidal
volume reading. Which of the following components should be
inspected first?
, A. The internal oxygen blender sensor module
B. The expiratory valve membrane and patient circuit connections
C. The main electrical power supply backup battery pack
D. The internal microprocessor motherboard assembly
Correct Answer: B
Rationale: A discrepancy between delivered and exhaled tidal volumes
during a circuit checkout most frequently indicates a physical leak
within the patient tubing circuit or around the expiratory valve assembly.
Inspecting connections and valve integrity is the primary
troubleshooting action.
Question 3
A patient is receiving volume-controlled continuous mandatory
ventilation. The high pressure limit alarm sounds continuously during
inspiration. The respiratory therapist notes absent breath sounds on the
left side, tracheal deviation to the right, and subcutaneous emphysema.
Which of the following conditions is the most likely cause?
A. Mucus plugging of the right mainstem bronchus
B. Left-sided tension pneumothorax
C. Right lower lobe pneumonia consolidation
D. Bilateral severe bronchial asthma exacerbation
Correct Answer: B
Rationale: The classic presentation of absent breath sounds on one side,
tracheal shift to the contralateral side, subcutaneous emphysema, and
high peak inspiratory pressures indicates a tension pneumothorax. This
,is an immediate, life-threatening complication of mechanical ventilation
requiring urgent needle decompression followed by chest tube insertion.
Question 4
When evaluating a patient's pulmonary function test results, the
respiratory therapist notes a total lung capacity of 50 percent of
predicted, a forced vital capacity of 55 percent of predicted, and a forced
expiratory volume in one second to forced vital capacity ratio of 85
percent. These findings are characteristic of which of the following
disorders?
A. Chronic bronchitis
B. Bronchial asthma
C. Idiopathic pulmonary fibrosis
D. Pulmonary emphysema
Correct Answer: C
Rationale: A reduced total lung capacity below the lower limit of normal
combined with a normal or elevated forced expiratory volume in one
second to forced vital capacity ratio defines a restrictive ventilatory
defect. Pulmonary fibrosis is a primary interstitial lung disease causing
parenchymal restriction.
Question 5
A patient with smoke inhalation injury is admitted to the emergency
department. Pulse oximetry reads 98 percent on room air, but the patient
remains cyanotic, anxious, and confused. Arterial blood gas analysis
reveals a normal partial pressure of oxygen and a calculated oxygen
saturation of 84 percent. Which of the following diagnostic tests should
the respiratory therapist recommend next?
, A. Repeat arterial blood gas with direct electrolyte panel
B. Co-oximetry analysis of an arterial blood sample
C. Pulmonary function spirometry testing
D. Standard posteroanterior chest radiography
Correct Answer: B
Rationale: Standard pulse oximeters measure only two wavelengths of
light and cannot differentiate between oxyhemoglobin and dysfunctional
hemoglobins like carboxyhemoglobin, yielding falsely high readings in
smoke inhalation. A co-oximetry panel is necessary to measure
functional and dysfunctional hemoglobins directly.
Question 6
While monitoring a mechanically ventilated patient in volume-controlled
ventilation, the respiratory therapist notes a peak inspiratory pressure of
45 cm H2O and a plateau pressure of 30 cm H2O with an inspiratory
flow of 60 liters per minute. What is the calculated airway resistance?
A. 0.25 cm H2O per L per second
B. 5.0 cm H2O per L per second
C. 15.0 cm H2O per L per second
D. 30.0 cm H2O per L per second
Correct Answer: C
Rationale: Airway resistance is calculated by subtracting the plateau
pressure from the peak inspiratory pressure, then dividing the result by
the inspiratory flow rate in liters per second. An inspiratory flow of 60
L/min equals 1 L/sec. Subtracting 30 from 45 gives 15 cm H2O, which
divided by 1 L/sec yields 15 cm H2O per L per second.
Answers with Rationale | Latest Edition 2026/2027
Question 1
A 55-year-old male with a history of severe chronic obstructive
pulmonary disease is admitted with acute shortness of breath and
peripheral edema. Arterial blood gas analysis on room air reveals pH
7.33, PaCO2 60 mm Hg, PaO2 54 mm Hg, and HCO3 32 mEq/L. Which
of the following oxygen delivery devices is most appropriate to initiate
controlled oxygen therapy?
A. Non-rebreathing mask at 15 liters per minute
B. Simple face mask at 10 liters per minute
C. Venturi mask delivering 24 percent oxygen
D. Nasal cannula at 6 liters per minute
Correct Answer: C
Rationale: Patients with chronic hypercapnia and acute on chronic
respiratory failure require precise, controlled low-flow oxygen
administration to prevent the removal of their hypoxic respiratory drive.
A Venturi mask delivers a fixed and exact fraction of inspired oxygen,
making it the safest option to avoid precipitating severe hypoventilation
in chronic obstructive pulmonary disease exacerbations.
Question 2
During a routine ventilator check in the intensive care unit, the
respiratory therapist performs a manual circuit leak test and observes a
significant difference between the set tidal volume and the exhaled tidal
volume reading. Which of the following components should be
inspected first?
, A. The internal oxygen blender sensor module
B. The expiratory valve membrane and patient circuit connections
C. The main electrical power supply backup battery pack
D. The internal microprocessor motherboard assembly
Correct Answer: B
Rationale: A discrepancy between delivered and exhaled tidal volumes
during a circuit checkout most frequently indicates a physical leak
within the patient tubing circuit or around the expiratory valve assembly.
Inspecting connections and valve integrity is the primary
troubleshooting action.
Question 3
A patient is receiving volume-controlled continuous mandatory
ventilation. The high pressure limit alarm sounds continuously during
inspiration. The respiratory therapist notes absent breath sounds on the
left side, tracheal deviation to the right, and subcutaneous emphysema.
Which of the following conditions is the most likely cause?
A. Mucus plugging of the right mainstem bronchus
B. Left-sided tension pneumothorax
C. Right lower lobe pneumonia consolidation
D. Bilateral severe bronchial asthma exacerbation
Correct Answer: B
Rationale: The classic presentation of absent breath sounds on one side,
tracheal shift to the contralateral side, subcutaneous emphysema, and
high peak inspiratory pressures indicates a tension pneumothorax. This
,is an immediate, life-threatening complication of mechanical ventilation
requiring urgent needle decompression followed by chest tube insertion.
Question 4
When evaluating a patient's pulmonary function test results, the
respiratory therapist notes a total lung capacity of 50 percent of
predicted, a forced vital capacity of 55 percent of predicted, and a forced
expiratory volume in one second to forced vital capacity ratio of 85
percent. These findings are characteristic of which of the following
disorders?
A. Chronic bronchitis
B. Bronchial asthma
C. Idiopathic pulmonary fibrosis
D. Pulmonary emphysema
Correct Answer: C
Rationale: A reduced total lung capacity below the lower limit of normal
combined with a normal or elevated forced expiratory volume in one
second to forced vital capacity ratio defines a restrictive ventilatory
defect. Pulmonary fibrosis is a primary interstitial lung disease causing
parenchymal restriction.
Question 5
A patient with smoke inhalation injury is admitted to the emergency
department. Pulse oximetry reads 98 percent on room air, but the patient
remains cyanotic, anxious, and confused. Arterial blood gas analysis
reveals a normal partial pressure of oxygen and a calculated oxygen
saturation of 84 percent. Which of the following diagnostic tests should
the respiratory therapist recommend next?
, A. Repeat arterial blood gas with direct electrolyte panel
B. Co-oximetry analysis of an arterial blood sample
C. Pulmonary function spirometry testing
D. Standard posteroanterior chest radiography
Correct Answer: B
Rationale: Standard pulse oximeters measure only two wavelengths of
light and cannot differentiate between oxyhemoglobin and dysfunctional
hemoglobins like carboxyhemoglobin, yielding falsely high readings in
smoke inhalation. A co-oximetry panel is necessary to measure
functional and dysfunctional hemoglobins directly.
Question 6
While monitoring a mechanically ventilated patient in volume-controlled
ventilation, the respiratory therapist notes a peak inspiratory pressure of
45 cm H2O and a plateau pressure of 30 cm H2O with an inspiratory
flow of 60 liters per minute. What is the calculated airway resistance?
A. 0.25 cm H2O per L per second
B. 5.0 cm H2O per L per second
C. 15.0 cm H2O per L per second
D. 30.0 cm H2O per L per second
Correct Answer: C
Rationale: Airway resistance is calculated by subtracting the plateau
pressure from the peak inspiratory pressure, then dividing the result by
the inspiratory flow rate in liters per second. An inspiratory flow of 60
L/min equals 1 L/sec. Subtracting 30 from 45 gives 15 cm H2O, which
divided by 1 L/sec yields 15 cm H2O per L per second.
