Chapter 5: Pulmonary Function Testing and Bedside Pulmonary Mechanics
Test Bank
MULTIPLE CHOICE
1. Which of the following major forces opposes inspiration?
a. Inspiratory flow
b. Surface tension
c. Airway resistance
d. Respiratory rate
ANS: C
The combination of lung compliance (C) and airway resistance (Raw) is the major force
opposing inspiration, whereas elastic recoil is the force responsible for passive normal
exhalation.
REF: p. 66
2. Pulmonary function testing has been ordered in an infant. Which of the following represents a
real risk to this infant?
a. The infant may require sedation for up to 3 hours.
b. If the infant cries, it will make the test invalid or open to misinterpretation.
c. The gases used for the PFT may be toxic for the infant.
d. The inability to feed the child 24 hours prior to the test
ANS: B
In infant testing, the subject may need to be lightly sedated in the laboratory for 2 to 3 hours
to complete a full set of studies. Sedation carries some risk, and testing should not be viewed
as routine. The NPO guidelines from the hospital sedation policy may allow infants who are
younger than 6 months to receive formula and solids for up to 6 hours, breast milk for up to 4
hours, and clear liquids for up to 2 hours before sedation. Children who are 6 months or older
may receive solids and liquids for up to 6 hours and clear liquids for up to 2 hours before
sedation.
REF: p. 66
3. Why must caution be exercised when using a face mask while performing pulmonary function
testing on neonates?
a. To prevent trigeminal nerve stimulation
b. To avoid necrosis of the facial skin
c. To prevent vagal reflexes
d. To prevent gastric insufflations
ANS: A
A face mask is required when testing neonates and infants. Caution must be exercised because
using a face mask can cause trigeminal nerve stimulation and induce vagal reflexes that may
alter the pattern of heart or respiratory rhythm.
REF: pp. 66-67
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, 4. The respiratory therapist places a face mask on an infant to measure FRC. What should the
therapist do to minimize the presence of air leaks and improve accuracy of the test?
a. Place a nose clip on the infant.
b. Minimize the amount of helium used during the test.
c. Minimize oxygen concentration and increase nitrogen concentration.
d. Apply petroleum jelly on the edges of the mask before applying the mask to the
face.
ANS: D
Applying petroleum jelly to the edges of a disposable mask is helpful for ensuring an airtight
seal with no leaks on the infant's face.
REF: p. 68
5. How is airway resistance calculated?
a. By dividing the airway occlusion pressure by the expiratory flow
b. By dividing the transpulmonary pressure by the expiratory flow
c. By multiplying the expiratory flow by the pressure gradient responsible for
initiating inspiration
d. By multiplying the expiratory occlusion pressure by the transpulmonary pressure
gradient
ANS: A
Airway resistance (Raw) reflects the nonelastic airway and tissue influences resisting gas
flow. Raw is calculated from the ratio of airway occlusion pressure to expiratory flow. Raw is
described in centimeters of water per liter per second (cm H2O/L/s).
REF: p. 68
6. Which of the following factors is the most important determinant of high airway resistance
and air trapping in small infants?
a. The small tidal volume
b. Small diameter of the airways
c. Excessive amount of mucus production
d. The length of the airways
ANS: B
Raw is dependent on the radius, length, and number of airways and varies with volume, flow,
and respiratory frequency. The small diameters of an infant's tracheobronchial tree result in
high resistance to gas flow.
REF: p. 68
7. On the partial expiratory flow–volume loop shown here, identify the point depicting the
“maximal expiratory flow at FRC.”
This study source was downloaded by 100000837848174 from CourseHero.com on 03-01-2022 14:57:27 GMT -06:00
https://www.coursehero.com/file/103516367/c5pdf/
Test Bank
MULTIPLE CHOICE
1. Which of the following major forces opposes inspiration?
a. Inspiratory flow
b. Surface tension
c. Airway resistance
d. Respiratory rate
ANS: C
The combination of lung compliance (C) and airway resistance (Raw) is the major force
opposing inspiration, whereas elastic recoil is the force responsible for passive normal
exhalation.
REF: p. 66
2. Pulmonary function testing has been ordered in an infant. Which of the following represents a
real risk to this infant?
a. The infant may require sedation for up to 3 hours.
b. If the infant cries, it will make the test invalid or open to misinterpretation.
c. The gases used for the PFT may be toxic for the infant.
d. The inability to feed the child 24 hours prior to the test
ANS: B
In infant testing, the subject may need to be lightly sedated in the laboratory for 2 to 3 hours
to complete a full set of studies. Sedation carries some risk, and testing should not be viewed
as routine. The NPO guidelines from the hospital sedation policy may allow infants who are
younger than 6 months to receive formula and solids for up to 6 hours, breast milk for up to 4
hours, and clear liquids for up to 2 hours before sedation. Children who are 6 months or older
may receive solids and liquids for up to 6 hours and clear liquids for up to 2 hours before
sedation.
REF: p. 66
3. Why must caution be exercised when using a face mask while performing pulmonary function
testing on neonates?
a. To prevent trigeminal nerve stimulation
b. To avoid necrosis of the facial skin
c. To prevent vagal reflexes
d. To prevent gastric insufflations
ANS: A
A face mask is required when testing neonates and infants. Caution must be exercised because
using a face mask can cause trigeminal nerve stimulation and induce vagal reflexes that may
alter the pattern of heart or respiratory rhythm.
REF: pp. 66-67
This study source was downloaded by 100000837848174 from CourseHero.com on 03-01-2022 14:57:27 GMT -06:00
https://www.coursehero.com/file/103516367/c5pdf/
, 4. The respiratory therapist places a face mask on an infant to measure FRC. What should the
therapist do to minimize the presence of air leaks and improve accuracy of the test?
a. Place a nose clip on the infant.
b. Minimize the amount of helium used during the test.
c. Minimize oxygen concentration and increase nitrogen concentration.
d. Apply petroleum jelly on the edges of the mask before applying the mask to the
face.
ANS: D
Applying petroleum jelly to the edges of a disposable mask is helpful for ensuring an airtight
seal with no leaks on the infant's face.
REF: p. 68
5. How is airway resistance calculated?
a. By dividing the airway occlusion pressure by the expiratory flow
b. By dividing the transpulmonary pressure by the expiratory flow
c. By multiplying the expiratory flow by the pressure gradient responsible for
initiating inspiration
d. By multiplying the expiratory occlusion pressure by the transpulmonary pressure
gradient
ANS: A
Airway resistance (Raw) reflects the nonelastic airway and tissue influences resisting gas
flow. Raw is calculated from the ratio of airway occlusion pressure to expiratory flow. Raw is
described in centimeters of water per liter per second (cm H2O/L/s).
REF: p. 68
6. Which of the following factors is the most important determinant of high airway resistance
and air trapping in small infants?
a. The small tidal volume
b. Small diameter of the airways
c. Excessive amount of mucus production
d. The length of the airways
ANS: B
Raw is dependent on the radius, length, and number of airways and varies with volume, flow,
and respiratory frequency. The small diameters of an infant's tracheobronchial tree result in
high resistance to gas flow.
REF: p. 68
7. On the partial expiratory flow–volume loop shown here, identify the point depicting the
“maximal expiratory flow at FRC.”
This study source was downloaded by 100000837848174 from CourseHero.com on 03-01-2022 14:57:27 GMT -06:00
https://www.coursehero.com/file/103516367/c5pdf/
