NBRC RPFT Registered Pulmonary Function Technologist

A spirometer is being calibrated using a 3-liter calibration syringe. The spirometer reads 2.88 liters on three consecutive trials. What is the most appropriate action?

• AContinue testing because the error is within acceptable limits
• BReplace the calibration syringe immediately
• CAdjust the spirometer calibration factor before testing
• DReport the spirometer as defective and remove it from service

Which of the following is the primary purpose of a body plethysmograph in pulmonary function testing?

• AMeasuring diffusion capacity of the lungs
• BMeasuring thoracic gas volume and airway resistance
• CAssessing exercise capacity during cardiopulmonary stress testing
• DEvaluating arterial blood gas values

During a nitrogen washout test for FRC measurement, which of the following would most likely cause an erroneously high result?

• AA leak in the breathing circuit
• BThe patient breathing room air instead of 100% oxygen
• CThe nitrogen analyzer reading lower than actual values
• DThe patient performing shallow breathing throughout the test

Which gas is used as the tracer in the single-breath diffusion capacity (DLCO) test?

• AHelium
• BNitrogen
• CCarbon monoxide
• DOxygen

A PFT lab is performing quality control on a blood gas analyzer. The control sample results fall outside the ±2 standard deviation (SD) range. What should the technologist do FIRST?

• ARun patient samples and flag the results as potentially inaccurate
• BRepeat the control sample to confirm the out-of-range result
• CReplace all electrodes in the blood gas analyzer
• DNotify the laboratory director and discontinue all testing

A helium dilution test for measuring FRC yields a significantly lower value than a body plethysmography test performed on the same patient. Which condition best explains this discrepancy?

• APulmonary fibrosis with restrictive disease
• BSevere emphysema with air trapping
• CHealthy lungs with normal ventilation
• DMild asthma in remission

When performing spirometry, a patient's FVC maneuver shows a plateau on the volume-time curve but the expiratory time is only 4 seconds. According to ATS/ERS standards, what should the technologist do?

• AAccept the maneuver because a plateau was achieved
• BReject the maneuver because the expiratory time must be at least 6 seconds
• CAccept the maneuver because a plateau with stable volume indicates adequate effort
• DRepeat the maneuver and have the patient blow for at least 15 seconds

During a cardiopulmonary exercise test (CPET), the patient's ventilatory equivalent for oxygen (VE/VO2) reaches its nadir and then begins to rise while VE/VCO2 continues to decrease. This point represents the:

• ARespiratory compensation point
• BAnaerobic threshold (ventilatory threshold 1)
• CPeak exercise capacity
• DLactate clearance point

Which of the following is the correct breath-hold time for a standard single-breath DLCO test according to ATS/ERS guidelines?

• A5 ± 1 seconds
• B10 ± 2 seconds
• C15 ± 3 seconds
• D20 ± 2 seconds

A patient's arterial blood gas results show: pH 7.28, PaCO2 55 mmHg, HCO3 26 mEq/L, PaO2 58 mmHg. How should these results be interpreted?

• ACompensated metabolic acidosis with hypoxemia
• BAcute respiratory acidosis with hypoxemia
• CChronic respiratory acidosis with adequate compensation
• DMixed respiratory and metabolic acidosis

A flow-volume loop shows a fixed flattening of both the inspiratory and expiratory limbs. This pattern is most consistent with:

• AVariable intrathoracic obstruction
• BVariable extrathoracic obstruction
• CFixed upper airway obstruction
• DSmall airway disease

What is the normal alveolar-arterial oxygen gradient (A-a gradient) for a healthy young adult breathing room air at sea level?

• A0–5 mmHg
• B5–15 mmHg
• C20–30 mmHg
• D35–45 mmHg

A pneumotachograph measures airflow by detecting:

• ATemperature changes caused by airflow across a heated wire
• BPressure differences across a known resistance element
• CUltrasonic frequency shifts caused by moving gas molecules
• DVolume displacement of a sealed bell spirometer

When performing a methacholine challenge test, a positive result is defined as a provocative concentration (or dose) that causes the FEV1 to decrease by at least:

• A10% from baseline
• B15% from baseline
• C20% from baseline
• D25% from baseline

A patient performs a bronchodilator response test. Pre-bronchodilator FEV1 is 2.50 L, post-bronchodilator FEV1 is 2.85 L, and predicted FEV1 is 3.00 L. According to the ATS/ERS 2021 interpretive strategies, is this a significant bronchodilator response?

• AYes, because the improvement exceeds 200 mL from baseline
• BNo, because the improvement is only 10% of the baseline value
• CYes, because the improvement exceeds 10% of the predicted FEV1
• DNo, because both FEV1 and FVC must improve to be significant

Which of the following conditions would cause an INCREASED diffusion capacity (DLCO)?

• AEmphysema
• BPulmonary fibrosis
• CPolycythemia
• DAnemia

During quality control of a body plethysmograph, the technologist should verify the box volume using a:

• A3-liter calibration syringe
• B50-mL isothermal reference volume
• CKnown-volume test lung simulator
• DPrecision digital barometer

A patient's spirometry results show: FEV1 65% predicted, FVC 90% predicted, FEV1/FVC ratio 55%. These results are most consistent with:

• ARestrictive lung disease
• BObstructive lung disease
• CMixed obstructive and restrictive disease
• DNormal spirometry with poor effort

When converting a gas volume from ATPS (ambient temperature and pressure, saturated) to BTPS (body temperature and pressure, saturated), the volume will:

• ADecrease because body temperature is higher than ambient temperature
• BIncrease because body temperature is higher than ambient temperature
• CRemain unchanged because water vapor pressure is the same
• DVary depending on whether the gas is nitrogen or oxygen

A patient scheduled for pulmonary function testing reports using a short-acting bronchodilator (albuterol) 2 hours before the appointment. What should the technologist recommend?

• AProceed with testing since 2 hours provides adequate washout
• BReschedule the test and instruct the patient to withhold short-acting bronchodilators for…
• CAdminister an additional dose of bronchodilator before testing
• DProceed with testing but only perform DLCO, not spirometry

During a maximum voluntary ventilation (MVV) test, a patient achieves a value of 45 L/min. The predicted value is 120 L/min, and the FEV1 is 1.8 L. What is the estimated MVV using the FEV1 × 40 formula, and how does it compare?

• AEstimated MVV is 72 L/min; the measured value is disproportionately low suggesting neurom…
• BEstimated MVV is 72 L/min; the measured value is within expected range for the patient's…
• CEstimated MVV is 54 L/min; the measured value confirms severe obstruction
• DEstimated MVV is 90 L/min; the measured value indicates normal ventilatory capacity

Which of the following electrode systems is used in a Clark electrode to measure PaO2?

• ASilver/silver chloride reference with a platinum cathode
• BGlass membrane with an internal buffer solution
• CCalomel reference electrode with a redox indicator
• DIon-selective membrane with a fluorescent sensor

A patient's 6-minute walk test (6MWT) results show a distance of 280 meters with SpO2 dropping from 96% to 84% during the test. The most appropriate interpretation is:

• ANormal exercise tolerance with acceptable desaturation
• BReduced exercise capacity with significant exercise-induced desaturation
• CNormal results that do not require further evaluation
• DInvalid test due to the low SpO2 reading

When measuring lung compliance, which of the following describes static compliance?

• AChange in volume per change in pressure measured during continuous airflow
• BChange in volume per change in pressure measured at points of no airflow
• CMaximum inspiratory pressure generated against an occluded airway
• DResistance to airflow measured in the conducting airways

A patient with suspected occupational asthma is referred for serial peak expiratory flow (PEF) monitoring. The recommended monitoring protocol typically requires PEF measurements at least:

• AOnce daily for one week
• BTwice daily for two weeks
• CFour times daily for at least two weeks, including work and non-work periods
• DOnce weekly for six months

The Severinghaus electrode in a blood gas analyzer measures:

• APartial pressure of oxygen (PaO2)
• BPartial pressure of carbon dioxide (PaCO2)
• CpH of arterial blood
• DHemoglobin oxygen saturation (SaO2)