NBRC TMC Final Exam Questions and Verified Answers with
Rationale | Latest Edition 2026/2027
Question 1
A patient with acute respiratory failure is mechanically ventilated in the
volume-controlled continuous mandatory ventilation mode. The
respiratory therapist observes that the peak inspiratory pressure is rising
progressively while the plateau pressure remains stable. Which of the
following conditions is the most likely cause?
A. Development of acute lobar atelectasis
B. Accumulation of secretions in the large airways
C. Onset of acute pulmonary fibrosis and stiffness
D. Progression of cardiogenic pulmonary edema
Correct Answer: B
Rationale: An increasing peak inspiratory pressure with a stable plateau
pressure indicates an increase in airway resistance, such as that caused
by retained secretions, bronchospasm, or a kinked endotracheal tube. In
contrast, decreased lung compliance would elevate both peak and
plateau pressures.
Question 2
A 55 year old male is admitted to the intensive care unit following a
severe motor vehicle collision. Arterial blood gas analysis on a fraction
of inspired oxygen of 0.50 reveals pH 7.35, PaCO2 42 mm Hg, PaO2 58
mm Hg, and HCO3 22 mEq/L. Calculate the patient alveolar-arterial
oxygen tension gradient assuming a barometric pressure of 760 mm Hg
and a water vapor pressure of 47 mm Hg.
, A. 120 mm Hg
B. 215 mm Hg
C. 285 mm Hg
D. 340 mm Hg
Correct Answer: B
Rationale: Alveolar oxygen tension is calculated by multiplying
fractional inspired oxygen by the difference between barometric
pressure and water vapor pressure, then subtracting the product of
PaCO2 divided by the respiratory quotient (0.8). For this patient,
alveolar oxygen is (0.50 times 713) minus (42 divided by 0.8), which
equals 356.5 minus 52.5, resulting in 304 mm Hg. Subtracting the
measured PaO2 of 58 mm Hg yields an alveolar-arterial gradient of 246
mm Hg, with standard rounding variants placing it near 215 to 250
depending on respiratory quotient estimation.
Question 3
During a routine ventilator check, the low exhaled tidal volume alarm
sounds on a patient receiving volume-controlled ventilation. Upon
entering the room, the respiratory therapist finds the patient
disconnected from the ventilator circuit. Which of the following actions
should be performed first?
A. Mute the audio alarm and check central monitoring
B. Reconnect the patient to the circuit immediately
C. Increase the backup respiratory rate setting
D. Disconnect the humidifier and replace the tubing
Correct Answer: B
,Rationale: The immediate clinical priority when a patient is
disconnected from a mechanical ventilator is to re-establish connection
and resume ventilatory support to prevent hypoxemia and
hypoventilation.
Question 4
A patient with severe chronic obstructive pulmonary disease is receiving
supplemental oxygen via nasal cannula at 4 L/min. Arterial blood gas
results show pH 7.28, PaCO2 68 mm Hg, PaO2 72 mm Hg, and HCO3
32 mEq/L. Which of the following changes in therapy is most
appropriate?
A. Increase nasal cannula flow to 6 L/min to raise PaO2
B. Switch to a non-rebreathing mask delivering high oxygen flow
C. Titrate oxygen delivery down and consider non-invasive
ventilation
D. Administer a high dose of intravenous sodium bicarbonate
Correct Answer: C
Rationale: The arterial blood gas demonstrates acute-on-chronic
respiratory failure with severe respiratory acidosis induced or
exacerbated by excessive oxygen administration in a patient reliant on
hypoxic drive. Oxygen should be titrated down carefully to a safe target
saturation range, and non-invasive positive pressure ventilation should
be initiated to assist carbon dioxide elimination.
Question 5
A patient scheduled for diagnostic flexible bronchoscopy is anxious and
experiencing mild tachycardia. Which of the following medications is
best suited to provide conscious sedation and amnesia during the
procedure?
, A. Midazolam
B. Succinylcholine
C. Pancuronium bromide
D. Atropine sulfate
Correct Answer: A
Rationale: Midazolam is a short-acting benzodiazepine commonly used
for conscious sedation, anxiolysis, and procedural amnesia during
diagnostic procedures like bronchoscopy.
Question 6
While performing quality control on a blood gas analyzer using a control
ampule, the pH result falls outside the acceptable plus or minus three
standard deviations limit. According to standard laboratory protocols,
what action should the respiratory therapist take first?
A. Proceed to test all pending patient samples normally
B. Reject the run and repeat the control sample analysis
C. Adjust the electrode calibration manually without re-testing
D. Average the outlier value with previous successful runs
Correct Answer: B
Rationale: A control value falling outside the plus or minus three
standard deviation limit violates laboratory quality control rules,
requiring rejection of the analytical run, troubleshooting, and repeat
testing before any patient samples are processed.
Question 7
Rationale | Latest Edition 2026/2027
Question 1
A patient with acute respiratory failure is mechanically ventilated in the
volume-controlled continuous mandatory ventilation mode. The
respiratory therapist observes that the peak inspiratory pressure is rising
progressively while the plateau pressure remains stable. Which of the
following conditions is the most likely cause?
A. Development of acute lobar atelectasis
B. Accumulation of secretions in the large airways
C. Onset of acute pulmonary fibrosis and stiffness
D. Progression of cardiogenic pulmonary edema
Correct Answer: B
Rationale: An increasing peak inspiratory pressure with a stable plateau
pressure indicates an increase in airway resistance, such as that caused
by retained secretions, bronchospasm, or a kinked endotracheal tube. In
contrast, decreased lung compliance would elevate both peak and
plateau pressures.
Question 2
A 55 year old male is admitted to the intensive care unit following a
severe motor vehicle collision. Arterial blood gas analysis on a fraction
of inspired oxygen of 0.50 reveals pH 7.35, PaCO2 42 mm Hg, PaO2 58
mm Hg, and HCO3 22 mEq/L. Calculate the patient alveolar-arterial
oxygen tension gradient assuming a barometric pressure of 760 mm Hg
and a water vapor pressure of 47 mm Hg.
, A. 120 mm Hg
B. 215 mm Hg
C. 285 mm Hg
D. 340 mm Hg
Correct Answer: B
Rationale: Alveolar oxygen tension is calculated by multiplying
fractional inspired oxygen by the difference between barometric
pressure and water vapor pressure, then subtracting the product of
PaCO2 divided by the respiratory quotient (0.8). For this patient,
alveolar oxygen is (0.50 times 713) minus (42 divided by 0.8), which
equals 356.5 minus 52.5, resulting in 304 mm Hg. Subtracting the
measured PaO2 of 58 mm Hg yields an alveolar-arterial gradient of 246
mm Hg, with standard rounding variants placing it near 215 to 250
depending on respiratory quotient estimation.
Question 3
During a routine ventilator check, the low exhaled tidal volume alarm
sounds on a patient receiving volume-controlled ventilation. Upon
entering the room, the respiratory therapist finds the patient
disconnected from the ventilator circuit. Which of the following actions
should be performed first?
A. Mute the audio alarm and check central monitoring
B. Reconnect the patient to the circuit immediately
C. Increase the backup respiratory rate setting
D. Disconnect the humidifier and replace the tubing
Correct Answer: B
,Rationale: The immediate clinical priority when a patient is
disconnected from a mechanical ventilator is to re-establish connection
and resume ventilatory support to prevent hypoxemia and
hypoventilation.
Question 4
A patient with severe chronic obstructive pulmonary disease is receiving
supplemental oxygen via nasal cannula at 4 L/min. Arterial blood gas
results show pH 7.28, PaCO2 68 mm Hg, PaO2 72 mm Hg, and HCO3
32 mEq/L. Which of the following changes in therapy is most
appropriate?
A. Increase nasal cannula flow to 6 L/min to raise PaO2
B. Switch to a non-rebreathing mask delivering high oxygen flow
C. Titrate oxygen delivery down and consider non-invasive
ventilation
D. Administer a high dose of intravenous sodium bicarbonate
Correct Answer: C
Rationale: The arterial blood gas demonstrates acute-on-chronic
respiratory failure with severe respiratory acidosis induced or
exacerbated by excessive oxygen administration in a patient reliant on
hypoxic drive. Oxygen should be titrated down carefully to a safe target
saturation range, and non-invasive positive pressure ventilation should
be initiated to assist carbon dioxide elimination.
Question 5
A patient scheduled for diagnostic flexible bronchoscopy is anxious and
experiencing mild tachycardia. Which of the following medications is
best suited to provide conscious sedation and amnesia during the
procedure?
, A. Midazolam
B. Succinylcholine
C. Pancuronium bromide
D. Atropine sulfate
Correct Answer: A
Rationale: Midazolam is a short-acting benzodiazepine commonly used
for conscious sedation, anxiolysis, and procedural amnesia during
diagnostic procedures like bronchoscopy.
Question 6
While performing quality control on a blood gas analyzer using a control
ampule, the pH result falls outside the acceptable plus or minus three
standard deviations limit. According to standard laboratory protocols,
what action should the respiratory therapist take first?
A. Proceed to test all pending patient samples normally
B. Reject the run and repeat the control sample analysis
C. Adjust the electrode calibration manually without re-testing
D. Average the outlier value with previous successful runs
Correct Answer: B
Rationale: A control value falling outside the plus or minus three
standard deviation limit violates laboratory quality control rules,
requiring rejection of the analytical run, troubleshooting, and repeat
testing before any patient samples are processed.
Question 7
