Question 1

The following pulmonary function test data are measured on a 61 year-old man complaining of shortness of breath:

Parameter Predicted Value Measured Value Predicted
FVC (L) 4.22 2.92 69
FEV1 (L) 3.25 2.66 81
FEV1/FVC 77 91
TLC (L) 6.54 3.63 55
RV (L) 2.78 1.79 64
DL,CO (mL/min/mm Hg) 24.2 11.3 47

Which disease process is most consistent with these data?

  1. Cystic fibrosis
  2. Emphysema
  3. Interstitial pulmonary fibrosis
  4. Asthma


Question 2

A patient has the following lung volume data:

Parameter Measured %Predicted
SVC (L) 2.95 71
FRC (L) 1.85 67
RV (L) 1.03 75
TLC (L) 3.98 67

The most likely interpretation of these data is:

  1. Obstructive pattern
  2. Restrictive pattern
  3. Hyperinflation
  4. Normal lung volumes


Question 3

A normal RV/TLC ratio value is indicated by:

  1. 25%
  2. 40%
  3. 45%
  4. 15%


Question 4

A patient has the following results from spirometry and N2 washout FRC determination:

Parameter Predicted Value Measured Value Predicted
VC 4.6L 4.7L 98%
FRC 8.2L 3.8L 216%
RV 4.8L 1.5 L 186%
TLC 10.2L 7.5L 136%
RV/TLC 47% 20%

Which of the following best explains these findings?

  1. The patient has severe hyperinflation
  2. The patient has severe air trapping
  3. The patient has normal lung volumes
  4. The patient has severe restriction


Question 5

A pulmonary function test is performed on a patient with the following results:

Parameter Predicted Actual(Measured)
FVC 3.20L 1.92L
FEV1 2.20L 1.94L
FEV1/FVC% 70% 85%
FEF25-75% 3.90L 2.80L
FRC 2.20L 1.43L
TLC 4.50L 2.84L

Which of the following is the appropriate interpretation for these results?

  1. Combined obstructive and restrictive disease
  2. Mild restrictive disease
  3. Mild obstructive disease
  4. Severe obstructive disease


Question 6

Carbon monoxide is the recommended gas used in determining DLCO because:

  1. It has a greater affinity for HB molecules than O2
  2. It will oxidize the iron atoms in the Hb molecules
  3. Reduces the solubility of O2 in the plasma
  4. It shifts the O2Hb dissociation curve to the right


Question 7

Diffusion studies can be performed by which of the following test?

  1. Single-breath technique (DLCOSB)
  2. FVC
  3. Oxygen consumption
  4. Steady-state technique (DLCOSS)


Question 8

Examples of restrictive disease processes include:

  1. Emphysema
  2. Pulmonary fibrosis
  3. Asthma
  4. Histoplasmosis
  5. ARDS


Question 9

Factors that can limit the rate of diffusion across the Alveolar/Capillary membrane include:

  1. Decreased surface area
  2. Increased distance for gas molecules to travel
  3. Decreased pressure gradients between air and blood
  4. Solubility coefficients of gases in a liquid


Question 10

In patients with emphysema the DL,CO is reduced because of:

  1. Low FEV1
  2. An increase in lung volume
  3. Decreased pulmonary artery pressure
  4. Loss of alveolar-capillary membrane surface area


Question 11

In single-breath diffusion capacity, the recommended time for breath holding is:

  1. 12 seconds
  2. 10 seconds
  3. 7 seconds
  4. 5 seconds


Question 12

Obstructive disorders with air-trapping display which of the following values

  1. Increased RV
  2. Increased VC
  3. Decreased FRC
  4. Normal TLC


Question 13

Patient conditions that result in increased DLCO values include which of the following?

  1. Exercise
  2. Left heart failure
  3. Emphysema
  4. Renal failure
  5. Asthma


Question 14

The movement of oxygen in alveolar gas, across the alveolar-capillary membrane, into the blood, and the exchange of carbon dioxide in the reverse direction is caused by:

  1. Ventilation
  2. Distribution
  3. Osmosis
  4. Diffusion


Question 15

The results of a patient’s spirometry are as follows:

Parameter Predicted Actual %Predicted
FVC 3.0L 1.9L 63%
FEV1 2.09L 1.85L 89%
FEV1/FVC% 70% 97%
FRC 2.50L 1.70L 68%
TLC 4.70L 3.0L 64%

The most appropriate interpretation of the study is:

  1. Patient has emphysema
  2. Patient has sarcoidosis
  3. Patient has asthma
  4. Normal PFT


Question 16

The volume of gas discarded before collecting the alveolar sample when performing a single breath diffusing capacity is called:

  1. Washout volume
  2. Compressible gas volume
  3. Deadspace volume
  4. Back extrapolated volume


Question 17

When performing a DLCOSB, the inspired volume should be at least what percent of the VC to be valid?

  1. 85%
  2. 100%
  3. 70%
  4. 80%


Question 18

When performing the single breath CO diffusion capacity (DLCOSB) test, the patient is instructed to inhale to TLC a mixture of:

  1. 0.1% CO, 10% helium, 20% O2 and remainder air
  2. 0.5% CO, 15% helium and remainder O2
  3. 0.5% CO, 10% helium, and remainder nitrogen
  4. 0.3% CO, 10% helium, and remainder air


Question 19

When preparing a patient for the administration of a diffusing capacity test

  1. The patient should be in the sitting position and wearing nose clips
  2. Supplemental O2 should be worn during a DLCO test
  3. The patient should sit and rest at least 5 minutes prior to the test
  4. The patient should refrain from smoking before the test.
  • The patient should eat a full meal prior to testing


Question 20

Which of the following are characteristic of a restrictive lung disease when measured volumes are compared with predicted volumes?

  1. The VC is increased
  2. The FRC is decreased
  3. The RV is decreased
  4. The RV/TLC ratio is increased


Question 21

Which of the following gas analyzers are typically needed to perform DLCO testing?

  1. CO analyzer
  2. N2 analyzer
  3. He analyzer
  4. CO2 analyzer


Question 22

Which of the following is a normal DLCO measurement?

  1. 30 ml CO/min/mmHg STPD
  2. 25 ml CO/min/mmHg STPD
  3. 35 ml CO/min/mmHg STPD
  4. 20 ml CO/min/mmHg STPD


Question 23

Which of the following is the most likely diagnosis on the basis of the pulmonary function results below?
FVC 80% of predicted
FEV1 59% of predicted
FEV1/FVC% 55% of predicted
FEF 25-75% 40% of predicted
DLCO 95% of predicted

  1. Chronic Bronchitis
  2. Kyphoscolios
  3. Emphysema
  4. Silicosis


Question 24

Which of the following methods can be used to determine lung volumes?

  1. Body plethysmograph
  2. Nitrogen washout study
  3. Bedside spirometry
  4. Helium dilution
Question 25

Which of the following patient conditions can decrease the DLCO?

  1. Decreased HB
  2. Exercise
  3. Supine position
  4. Lung resection