Deck 4: Lung Volumes,airway Resistance,and Gas Distribution Tests

Question 1

A patient with pulmonary fibrosis has lung volumes measured using the open-circuit method and by plethysmography with the following results: Which of the following best explains these results?

A) This is a normal pattern for the patient's diagnosis.
B) The FRC by N₂ washout is erroneously low.
C) The V_TG is erroneously low.
D) The predicted FRC is incorrect.

Answer 1

A

Question 2

During an SBN₂ test,an increased slope of phase III is:

A) Consistent with severe restrictive disease
B) Indicative of uneven distribution of gas within the lungs
C) Usually caused by an accelerated heart rate
D) Diagnostic of increased anatomic dead space

Answer 2

B

Question 3

The reported value for V_TG (FRCpleth)should be:

A) Averaged from three acceptable maneuvers
B) The largest value from three acceptable maneuvers
C) Reproducible within 1%
D) Measured with the subject panting at 5 Hz

Answer 3

A

Question 4

A subject has the following lung volumes measured using a body plethysmograph: These values are consistent with which of the following?

A) An obstructive pattern such as emphysema
B) A restrictive pattern such as sarcoidosis
C) Normal lung volumes
D) A calculation error involving the FRC

Question 5

The following raw data are obtained from spirometry and a He-dilution FRC test (all values have been corrected to BTPS): What is the patient's RV?

A) 0.8 L (BTPS)
B) 1.8 L (BTPS)
C) 2.3 L (BTPS)
D) 2.6 L (BTPS)

Question 6

A subject has the following measurements obtained during pulmonary function testing: These findings are consistent with:

A) Normal pulmonary function
B) Severe obstruction with air trapping
C) Mild restriction
D) A leak during the FRC determination

Question 7

The following data are obtained during a closed-circuit FRC determination: Which of the following is the FRC?

A) 1.32 L BTPS
B) 1.50 L BTPS
C) 1.55 L ATPS
D) 2.17 L ATPS

Question 8

Which of the following combinations are characteristic of a restrictive pattern?

A) Reduced VC,reduced TLC,normal RV/TLC
B) Reduced FRC,elevated TLC,normal RV/TLC
C) Elevated RV,elevated TLC,elevated RV/TLC
D) Reduced FRC,elevated V_TG

Question 9

The following FRC_pleth values are obtained with a body plethysmograph: Maneuver 1: 2.35 L
Maneuver 2: 2.30 L
Maneuver 3: 2.15 L
According to the ATS-ERS standards,what should the technologist's next step be?

A) Report the mean of the three maneuvers
B) Perform another maneuver
C) Report the largest value
D) Report the median value

Question 10

A subject with an FEV₁/FVC ratio of 37% performs a 7-minute N₂ washout test. After 7 minutes,the alveolar N₂ concentration is 5.7%.This is consistent with which
Of the following?

A) Chronic bronchitis
B) Idiopathic pulmonary fibrosis
C) Pneumoconiosis
D) A right-to-left shunt

Question 11

The following raw data are obtained from spirometry and a He-dilution FRC test (all values have been corrected to BTPS): What is the patient's TLC?

A) 5.5 L (BTPS)
B) 6.0 L (BTPS)
C) 4.7 L (BTPS)
D) 7.3 L (BTPS)

Question 12

Calculate the FRC from the closed-circuit method using the following data:

A) 4.50 L (BTPS)
B) 3.99 L (BTPS)
C) 3.77 L (BTPS)
D) 2.24 L (BTPS)

Question 13

To measure FRC in a body plethysmograph,the V_TG should be measured by:

A) Closing the shutter at a point of zero flow
B) Having the patient pant rapidly and deeply
C) Closing the shutter at end-expiration
D) Performing a combined Raw/V_TG maneuver

Question 14

A subject has these lung volumes measured using a body plethysmograph: These values are consistent with:

A) An obstructive pattern such as emphysema
B) A restrictive pattern such as sarcoidosis
C) Normal lung volumes
D) A calculation error involving the FRC

Question 15

A subject with an RV that is 60% of the predicted value and an RV/TLC ratio of approximately 20% would most likely have:

A) An obstructive disease pattern
B) A restrictive disease pattern
C) Combined obstruction and restriction
D) Normal lung function

Question 16

Which of the following is true when comparing dilutional lung volumes with body plethysmography in subjects who have severe obstruction?

A) N₂ washout overestimates TLC.
B) He rebreathing underestimates TLC.
C) Single-breath washout compares favorably with plethysmography.
D) Closed-circuit method overestimates FRC.

Question 17

To measure accurately the V_TG (FRCpleth)_,the patient should be instructed to do which of the following?

A) Breathe normally during closure of the shutter.
B) Pant rapidly and deeply.
C) Pant about once per second.
D) Hold his or her breath as soon as the shutter closes.

Question 18

A subject has the following results from spirometry and N₂ washout FRC determination: Which of the following best explains these findings?

A) The subject has normal lung volumes.
B) The subject has severe air trapping.
C) A leak occurred during the VC test.
D) A leak occurred during the FRC test.

Question 19

The following data are obtained from spirometry and a He dilution FRC test (all values have been corrected to BTPS): What is the patient's RV/TLC ratio?

A) 22%
B) 33%
C) 38%
D) 43%

Question 20

A subject in a plethysmograph has his Raw measured as 2.2 cm H₂O/L/sec at a lung volume of 3.7 L.The calculated sGaw for this patient is which of the following?

A) 0.59 cm H₂O/L/sec/L
B) 0.45 cm H₂O/L/sec/L
C) 0.27 cm H₂O/L/sec/L
D) 0.12 cm H₂O/L/sec/L

Question 21

By performing a combined Raw and V_TG maneuver in a plethysmograph,a subject has the following values determined: This subject's sGaw (specific conductance)would be:

A) 0.04 L/sec/cm H₂O/L
B) 0.17 L/sec/cm H₂O/L
C) 0.67 L/sec/cm H₂O/L
D) 1.50 L/sec/cm H₂O/L

Question 22

What is the correct pant rate for measuring airway resistance or conductance?

A) 1.0 to 1.5 Hz
B) 60 to 90 breaths/min
C) 90 to 120 breaths/min
D) 0.5 to 1.0 Hz