Pilbeam Mech Vent Test Bank Answer Key
Teacher’s Edition
Chapter 01: Basic Terms and Concepts of Mechanical Ventilation
Cairo: Pilbeam’s Mechanical Ventilation: Physiological and Clinical Applications, 7th
Edition
MULTIPLE CHOICE
1. The body’s mechanism for conducting air in and out of the lungs is known as which of the following?
a. External respiration
b. Internal respiration
c. Spontaneous ventilation
d. Mechanical ventilation
ANS: C
The conduction of air in and out of the body is known as ventilation. Since the question asks for the body’s
mechanism, this would be spontaneous ventilation. External respiration involves the exchange of oxygen (O 2)
and carbon dioxide (CO2) between the alveoli and the pulmonary capillaries. Internal respiration occurs at the
cellular level and involves movement of oxygen from the systemic blood into the cells.
2. Which of the following are involved in external respiration?
a. Red blood cells and body cells
b. Scalenes and trapezius muscles
c. Alveoli and pulmonary capillaries
d. External oblique and transverse abdominal muscles
ANS: C
External respiration involves the exchange of oxygen and carbon dioxide (CO 2) between the alveoli and the
pulmonary capillaries. Internal respiration occurs at the cellular level and involves movement of oxygen from
the systemic blood into the cells. Scalene and trapezius muscles are accessory muscles of inspiration. External
oblique and transverse abdominal muscles are accessory muscles of expiration.
3. The graph that shows intrapleural pressure changes during normal spontaneous breathing is depicted by which
of the following?
a.
b.
, c.
d.
ANS: B
During spontaneous breathing, the intrapleural pressure drops from about 5 cm H2O at end-expiration to
about 10 cm H2O at end-inspiration. The graph depicted for answer B shows that change from 5 cm H2O to
10 cm H2O.
4. During spontaneous inspiration alveolar pressure (P A) is about ________________.
a. 1 cm H2O
b. +1 cm H2O
c. 0 cm H2O
d. 5 cm H2O
ANS: A
During normal spontaneous ventilation alveolar pressure will become 1 cm H2O which is the lowest. During
the exhalation of a normal spontaneous breath the alveolar pressure will become +1 cm H 2O.
5. The pressure required to maintain alveolar inflation is known as which of the following?
a. Transairway pressure (PTA)
b. Transthoracic pressure (PTT)
c. Transrespiratory pressure (PTR)
d. Transpulmonary pressure (PL)
ANS: D
The definition of transpulmonary pressure (PL) is the pressure required to maintain alveolar inflation.
Transairway pressure (PTA) is the pressure gradient required to produce airflow in the conducting tubes.
Transrespiratory pressure (PTR) is the pressure to inflate the lungs and airways during positive-pressure
ventilation. Transthoracic pressure (PTT) represents the pressure required to expand or contract the lungs and
the chest wall at the same time.
6. Calculate the pressure needed to overcome airway resistance during positive-pressure ventilation when the
proximal airway pressure (Pawo) is 35 cm H2O and the alveolar pressure (PA) is 5 cm H2O.
a. 7 cm H2O
b. 30 cm H2O
c. 40 cm H2O
d. 175 cm H2O
ANS: B
, The transairway pressure (PTA) is used to calculate the pressure required to overcome airway resistance during
mechanical ventilation. This formula is PTA = Pawo PA.
7. The term used to describe the tendency of a structure to return to its original form after being stretched or acted
on by an outside force is which of the following?
a. Elastance
b. Compliance
c. Viscous resistance
d. Distending pressure
ANS: A
The elastance of a structure is the tendency of that structure to return to its original shape after being stretched.
The more elastance a structure has, the more difficult it is to stretch. The compliance of a structure is the ease
with which the structure distends or stretches. Compliance is the opposite of elastance. Viscous resistance is
the opposition to movement offered by adjacent structures such as the lungs and their adjacent organs.
Distending pressure is pressure required to maintain inflation, for example, alveolar distending pressure.
8. Calculate the pressure required to achieve a tidal volume of 400 mL for an intubated patient with a respiratory
system compliance of 15 mL/cm H2O.
a. 6 cm H2O
b. 26.7 cm H2O
c. 37.5 cm H2O
d. 41.5 cm H2O
ANS: B
ΔC = ΔV/ΔP then ΔP = ΔV/ΔC
9. Which of the following conditions causes pulmonary compliance to increase?
a. Asthma
b. Kyphoscoliosis
c. Emphysema
d. Acute respiratory distress syndrome (ARDS)
ANS: C
Emphysema causes an increase in pulmonary compliance, whereas ARDS and kyphoscoliosis cause decreases
in pulmonary compliance. Asthma attacks cause increase in airway resistance.
10. Calculate the effective static compliance (Cs) given the following information about a patient receiving
mechanical ventilation: peak inspiratory pressure (PIP) is 56 cm H 2O, plateau pressure (Pplat) is 40 cm H2O,
exhaled tidal volume (VT) is 650 mL, and positive end-expiratory pressure (PEEP) is 10 cm H 2O.
a. 14.1 mL/cm H2O
b. 16.3 mL/cm H2O
c. 21.7 mL/cm H2O
d. 40.6 mL/cm H2O
ANS: C
The formula for calculating effective static compliance is Cs = VT/(Pplat EEP).
11. Based upon the following patient information, calculate the patient’s static lung compliance: exhaled tidal
volume (VT) is 675 mL, peak inspiratory pressure (PIP) is 28 cm H2O, plateau pressure (Pplat) is 8 cm H2O, and
PEEP is set at 5 cm H 2O.
a. 0.02 L/cm H2O
, b. 0.03 L/cm H2O
c. 0.22 L/cm H2O
d. 0.34 L/cm H2O
ANS: C
The formula for calculating effective static compliance is Cs = VT/(Pplat EEP).
12. A patient receiving mechanical ventilation has an exhaled tidal volume (VT) of 500 mL and a positive end-
expiratory pressure setting (PEEP) of 5 cm H2O. Patient-ventilator system checks reveal the following data:
Time PIP (cm H2O) Pplat (cm H2O)
0600 27 15
0800 29 15
1000 36 13
The respiratory therapist should recommend which of the following for this patient?
1. Tracheobronchial suctioning
2. Increase in the set tidal volume
3. β adrenergic bronchodilator therapy
4. Increase positive end-expiratory pressure
a. 1 and 3 only
b. 2 and 4 only
c. 1, 2, and 3 only
d. 2, 3, and 4 only
ANS: A
Calculate the transairway pressure (PTA) by subtracting the plateau pressure from the peak inspiratory pressure.
Analyzing the PTA will show any changes in the pressure needed to overcome airway resistance. Analyzing the
Pplateau will demonstrate any changes in compliance. The Pplateau remained the same for the first two checks and
then actually dropped at the 1000-hour check. Analyzing the PTA, however, shows a slight increase between
0600 and 0800 (from 12 to 14 cm H2O) and then a sharp increase to 23 cm H2O at 1000. Increases in PTA
signify increases in airway resistance. Airway resistance may be caused by secretion buildup, bronchospasm,
mucosal edema, and mucosal inflammation. Tracheobronchial suctioning will remove any secretion buildup,
and a β adrenergic bronchodilator will reverse bronchospasm. Increasing the tidal volume will add to the
airway resistance according to Poiseuille’s law. Increasing the PEEP will not address the root of this patient’s
problem; the patient’s compliance is normal.
13. The values below pertain to a patient who is being mechanically ventilated with a measured exhaled tidal
volume (VT) of 700 mL.
Time Peak Inspiratory Plateau Pressure (cm H2O)
Pressure (cm H2O)
0800 35 30
1000 39 34
1100 45 39
1130 50 44
Analysis of this data points to which of the following conclusions?
a. Airway resistance is increasing.
b. Airway resistance is decreasing.
c. Lung compliance is increasing.
d. Lung compliance is decreasing.
ANS: D
Teacher’s Edition
Chapter 01: Basic Terms and Concepts of Mechanical Ventilation
Cairo: Pilbeam’s Mechanical Ventilation: Physiological and Clinical Applications, 7th
Edition
MULTIPLE CHOICE
1. The body’s mechanism for conducting air in and out of the lungs is known as which of the following?
a. External respiration
b. Internal respiration
c. Spontaneous ventilation
d. Mechanical ventilation
ANS: C
The conduction of air in and out of the body is known as ventilation. Since the question asks for the body’s
mechanism, this would be spontaneous ventilation. External respiration involves the exchange of oxygen (O 2)
and carbon dioxide (CO2) between the alveoli and the pulmonary capillaries. Internal respiration occurs at the
cellular level and involves movement of oxygen from the systemic blood into the cells.
2. Which of the following are involved in external respiration?
a. Red blood cells and body cells
b. Scalenes and trapezius muscles
c. Alveoli and pulmonary capillaries
d. External oblique and transverse abdominal muscles
ANS: C
External respiration involves the exchange of oxygen and carbon dioxide (CO 2) between the alveoli and the
pulmonary capillaries. Internal respiration occurs at the cellular level and involves movement of oxygen from
the systemic blood into the cells. Scalene and trapezius muscles are accessory muscles of inspiration. External
oblique and transverse abdominal muscles are accessory muscles of expiration.
3. The graph that shows intrapleural pressure changes during normal spontaneous breathing is depicted by which
of the following?
a.
b.
, c.
d.
ANS: B
During spontaneous breathing, the intrapleural pressure drops from about 5 cm H2O at end-expiration to
about 10 cm H2O at end-inspiration. The graph depicted for answer B shows that change from 5 cm H2O to
10 cm H2O.
4. During spontaneous inspiration alveolar pressure (P A) is about ________________.
a. 1 cm H2O
b. +1 cm H2O
c. 0 cm H2O
d. 5 cm H2O
ANS: A
During normal spontaneous ventilation alveolar pressure will become 1 cm H2O which is the lowest. During
the exhalation of a normal spontaneous breath the alveolar pressure will become +1 cm H 2O.
5. The pressure required to maintain alveolar inflation is known as which of the following?
a. Transairway pressure (PTA)
b. Transthoracic pressure (PTT)
c. Transrespiratory pressure (PTR)
d. Transpulmonary pressure (PL)
ANS: D
The definition of transpulmonary pressure (PL) is the pressure required to maintain alveolar inflation.
Transairway pressure (PTA) is the pressure gradient required to produce airflow in the conducting tubes.
Transrespiratory pressure (PTR) is the pressure to inflate the lungs and airways during positive-pressure
ventilation. Transthoracic pressure (PTT) represents the pressure required to expand or contract the lungs and
the chest wall at the same time.
6. Calculate the pressure needed to overcome airway resistance during positive-pressure ventilation when the
proximal airway pressure (Pawo) is 35 cm H2O and the alveolar pressure (PA) is 5 cm H2O.
a. 7 cm H2O
b. 30 cm H2O
c. 40 cm H2O
d. 175 cm H2O
ANS: B
, The transairway pressure (PTA) is used to calculate the pressure required to overcome airway resistance during
mechanical ventilation. This formula is PTA = Pawo PA.
7. The term used to describe the tendency of a structure to return to its original form after being stretched or acted
on by an outside force is which of the following?
a. Elastance
b. Compliance
c. Viscous resistance
d. Distending pressure
ANS: A
The elastance of a structure is the tendency of that structure to return to its original shape after being stretched.
The more elastance a structure has, the more difficult it is to stretch. The compliance of a structure is the ease
with which the structure distends or stretches. Compliance is the opposite of elastance. Viscous resistance is
the opposition to movement offered by adjacent structures such as the lungs and their adjacent organs.
Distending pressure is pressure required to maintain inflation, for example, alveolar distending pressure.
8. Calculate the pressure required to achieve a tidal volume of 400 mL for an intubated patient with a respiratory
system compliance of 15 mL/cm H2O.
a. 6 cm H2O
b. 26.7 cm H2O
c. 37.5 cm H2O
d. 41.5 cm H2O
ANS: B
ΔC = ΔV/ΔP then ΔP = ΔV/ΔC
9. Which of the following conditions causes pulmonary compliance to increase?
a. Asthma
b. Kyphoscoliosis
c. Emphysema
d. Acute respiratory distress syndrome (ARDS)
ANS: C
Emphysema causes an increase in pulmonary compliance, whereas ARDS and kyphoscoliosis cause decreases
in pulmonary compliance. Asthma attacks cause increase in airway resistance.
10. Calculate the effective static compliance (Cs) given the following information about a patient receiving
mechanical ventilation: peak inspiratory pressure (PIP) is 56 cm H 2O, plateau pressure (Pplat) is 40 cm H2O,
exhaled tidal volume (VT) is 650 mL, and positive end-expiratory pressure (PEEP) is 10 cm H 2O.
a. 14.1 mL/cm H2O
b. 16.3 mL/cm H2O
c. 21.7 mL/cm H2O
d. 40.6 mL/cm H2O
ANS: C
The formula for calculating effective static compliance is Cs = VT/(Pplat EEP).
11. Based upon the following patient information, calculate the patient’s static lung compliance: exhaled tidal
volume (VT) is 675 mL, peak inspiratory pressure (PIP) is 28 cm H2O, plateau pressure (Pplat) is 8 cm H2O, and
PEEP is set at 5 cm H 2O.
a. 0.02 L/cm H2O
, b. 0.03 L/cm H2O
c. 0.22 L/cm H2O
d. 0.34 L/cm H2O
ANS: C
The formula for calculating effective static compliance is Cs = VT/(Pplat EEP).
12. A patient receiving mechanical ventilation has an exhaled tidal volume (VT) of 500 mL and a positive end-
expiratory pressure setting (PEEP) of 5 cm H2O. Patient-ventilator system checks reveal the following data:
Time PIP (cm H2O) Pplat (cm H2O)
0600 27 15
0800 29 15
1000 36 13
The respiratory therapist should recommend which of the following for this patient?
1. Tracheobronchial suctioning
2. Increase in the set tidal volume
3. β adrenergic bronchodilator therapy
4. Increase positive end-expiratory pressure
a. 1 and 3 only
b. 2 and 4 only
c. 1, 2, and 3 only
d. 2, 3, and 4 only
ANS: A
Calculate the transairway pressure (PTA) by subtracting the plateau pressure from the peak inspiratory pressure.
Analyzing the PTA will show any changes in the pressure needed to overcome airway resistance. Analyzing the
Pplateau will demonstrate any changes in compliance. The Pplateau remained the same for the first two checks and
then actually dropped at the 1000-hour check. Analyzing the PTA, however, shows a slight increase between
0600 and 0800 (from 12 to 14 cm H2O) and then a sharp increase to 23 cm H2O at 1000. Increases in PTA
signify increases in airway resistance. Airway resistance may be caused by secretion buildup, bronchospasm,
mucosal edema, and mucosal inflammation. Tracheobronchial suctioning will remove any secretion buildup,
and a β adrenergic bronchodilator will reverse bronchospasm. Increasing the tidal volume will add to the
airway resistance according to Poiseuille’s law. Increasing the PEEP will not address the root of this patient’s
problem; the patient’s compliance is normal.
13. The values below pertain to a patient who is being mechanically ventilated with a measured exhaled tidal
volume (VT) of 700 mL.
Time Peak Inspiratory Plateau Pressure (cm H2O)
Pressure (cm H2O)
0800 35 30
1000 39 34
1100 45 39
1130 50 44
Analysis of this data points to which of the following conclusions?
a. Airway resistance is increasing.
b. Airway resistance is decreasing.
c. Lung compliance is increasing.
d. Lung compliance is decreasing.
ANS: D
