Deck 1: Basic Terms and Concepts of Mechanical Ventilation

Question 1

The patient-ventilator data over the past few hours demonstrates an increased peak inspiratory pressure (PIP)with a constant transairway pressure (P_TA).The respiratory therapist should conclude which of the following?

A) Static compliance (C_S)has increased.
B) Static compliance (C_S)has decreased.
C) Airway resistance (R_aw)has increased.
D) Airway resistance (R_aw )has decreased.

Answer 1

Static compliance (C_S)has decreased.

Question 2

A patient receiving mechanical ventilation has an exhaled tidal volume (V_T)of 500 mL and a positive-end expiratory pressure setting (PEEP)of 5 cm H₂O.Patient-ventilator system checks reveal the following data: The respiratory therapist should recommend which of the following for this patient?
1)Tracheobronchial suctioning
2)Increase in the set tidal volume
3)Beta 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

Answer 2

1 and 3 only

Question 3

Based upon the following patient information calculate the patient's static lung compliance: exhaled tidal volume (V_T)is 675 mL,peak inspiratory pressure (PIP)is 28 cm H₂O,plateau pressure (P_plateau)is 8 cm H₂O,and PEEP is set at 5 cm H₂O.

A) 0.02 L/cm H₂O
B) 0.03 L/cm H₂O
C) 0.22 L/cm H₂O
D) 0.34 L/cm H₂O

Answer 3

0.22 L/cm H₂O

Question 4

The values below pertain to a patient who is being mechanically ventilated with a measured exhaled tidal volume (V_T )of 700 mL. Analysis of this data points to which of the following conclusions?

A) Airway resistance in increasing.
B) Airway resistance is decreasing.
C) Lung compliance is increasing.
D) Lung compliance is decreasing.

Question 5

Calculate the pressure needed to overcome airway resistance during positive pressure ventilation when the proximal airway pressure (P_Aw)is 35 cm H₂O and the alveolar pressure (P_A)is 5 cm H₂O.

A) 7 cm H₂O
B) 30 cm H₂O
C) 40 cm H₂O
D) 175 cm H₂O

Question 6

The pressure required to maintain alveolar inflation is known as which of the following?

A) Transairway pressure (P_TA )
B) Transthoracic pressure (P_TT)
C) Transrespiratory pressure (P_TR)
D) Transpulmonary pressure (P_L)

Question 7

An increase in peak inspiratory pressure (PIP)without an increase in plateau pressure (P_plateau)is associated with which of the following?

A) Increase in static compliance (C_S)
B) Decrease in static compliance (C_S)
C) Increase in airway resistance
D) Decrease in airway resistance

Question 8

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

Question 9

The formula used for the calculation of static compliance (C_S)is which of the following?

A) (Peak pressure (PIP)- EEP)/tidal volume (V_T) C_S = (PIP-EEP)/V_T
B) (Plateau pressure (P_plateau)- EEP/tidal volume (V_T) C_S = (P_plateau - EEP)/V_T
C) Tidal volume/(plateau pressure - EEP) C_S = V_T/(P_plateau - EEP)
D) Tidal volume /(peak pressure (PIP)- plateau pressure (P_plateau )) C_{S =} V_T /(PIP- P_plateau)

Question 10

Calculate airway resistance (R_aw )for a ventilator patient,in cm H₂O/L/sec,when the peak inspiratory pressure (PIP)is 50 cm H₂O,the plateau pressure (P_plateau)is 15 cm H₂O,and the set flow rate is 60 L/min.

A) 0.58 R_aw
B) 1.2 R_aw
C) 35 R_aw
D) 50 R_aw

Question 11

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

Question 12

The graph that shows intrapleural pressure changes during normal spontaneous breathing is depicted by which of the following?

A)
B)
C)
D)

Question 13

Plateau pressure (P_plateau)is measured during which phase of the ventilatory cycle?

A) Inspiration
B) End-inspiration
C) Expiration
D) End-expiration

Question 14

Calculate the effective static compliance (C_s)given the following information about a patient receiving mechanical ventilation: peak inspiratory pressure (PIP)is 56 cm H₂O,plateau pressure (P_plateau)is 40 cm H₂O,exhaled tidal volume (V_T)is 650 mL,and positive-end expiratory pressure (PEEP)is 10 cm H₂O.

A) 14.1 mL/cm H₂O
B) 16.3 mL/ cm H₂O
C) 21.7 mL/cm H₂O
D) 40.6 mL/cm H₂O

Question 15

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

Question 16

The respiratory therapist should expect which of the following findings while ventilating a patient with acute respiratory distress syndrome (ARDS)?

A) An elevated plateau pressure (P_plateau)
B) A decreased elastic resistance
C) A low peak inspiratory pressure (PIP)
D) A large transairway pressure (P_TA)gradient

Question 17

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

Question 18

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

Question 19

The condition that causes pulmonary compliance to increase is which of the following?

A) Asthma
B) Kyphoscoliosis
C) Emphysema
D) Acute respiratory distress syndrome (ARDS)

Question 20

The condition that is associated with an increase in airway resistance is which of the following?

A) Pulmonary edema
B) Bronchospasm
C) Fibrosis
D) Ascites

Question 21

The ventilator that functions most physiologically uses which of the following?

A) Open loop
B) Double circuit
C) Positive pressure
D) Negative pressure

Question 22

Compute the inspiratory time necessary to ensure 100% of the volume is delivered to an intubated patient with a C_s = 60 mL/cm H₂O and the R_aw = 6 cm H₂O/(L/sec).

A) 0.36 sec
B) 0.5 sec
C) 1.4 sec
D) 1.8 sec

Question 23

Use this figure to compute the static compliance (C_S)for an intubated patient with an exhaled tidal volume (V_T)of 500 mL.

A) 14 mL/cm H₂O
B) 20 mL/cm H₂O
C) 33 mL/cm H₂O
D) 50 mL/cm H₂O

Question 24

Use this figure to compute the static compliance for an intubated patient with an inspiratory flow rate set at 70 L/min.

A) 0.2 cm H₂O/(L/sec)
B) 11.7 cm H₂O/(L/sec)
C) 16.7 cm H₂O/(L/sec)
D) 20 cm H₂O/(L/sec)

Question 25

Air accidently trapped in the lungs due to mechanical ventilation is known as which of the following?

A) Plateau pressure (P_plateau)
B) Functional residual capacity (FRC)
C) Extrinsic positive end expiratory pressure (extrinsic PEEP)
D) Intrinsic positive end expiratory pressure (intrinsic PEEP)

Question 26

Calculate the static compliance (C_S),in mL/cm H₂O,when PIP is 26 cm H₂O,plateau pressure (P_plateau)is 19 cm H₂O,baseline pressure is 5 cm H₂O and exhaled tidal volume (V_T)is 425 mL.

A) 16
B) 20
C) 22
D) 30

Question 27

Evaluate the combinations of compliance and resistance and select the combination that will cause the lungs to fill fastest.

A) C_s = 0.1 L/cm H₂O R_aw = 1 cm H₂O/(L/sec)
B) C_s = 0.1 L/cm H₂O R_aw = 10 cm H₂O/(L/sec)
C) C_s = 0.03 L/cm H₂O R_aw = 1 cm H₂O/(L/sec)
D) C_s = 0.03 L/cm H₂O R_aw = 10 cm H₂O/(L/sec)

Question 28

Evaluate the combinations of compliance and resistance and select the combination that will cause the lungs to empty slowest.

A) C_S = 0.05 L/cm H₂O R_aw = 2 cm H₂O/(L/sec)
B) C_S = 0.05 L/cm H₂O R_aw = 6 cm H₂O/(L/sec)
C) C_S = 0.03 L/cm H₂O R_aw = 5 cm H₂O/(L/sec)
D) C_S = 0.03 L/cm H₂O R_aw = 8 cm H₂O/(L/sec)

Question 29

Calculate the inspiratory time necessary to ensure 98% of the volume is delivered to a patient with a C_s = 40 mL/cm H₂O and the R_aw = 1 cm H₂O/(L/sec).

A) 0.04 sec
B) 0.16 sec
C) 1.6 sec
D) 4.0 sec

Question 30

Calculate airway resistance (R_aw)for a ventilator patient,in cm H₂O/L/sec,with the following information: Peak inspiratory pressure (PIP)is 20 cm H₂O,plateau pressure (P_plateau)is 15 cm H₂O,PEEP is 5 cm H₂O,and set flow rate is 50 L/min.

A) 5 R_aw
B) 6 R_aw
C) 10 R_aw
D) 15 R_aw

Question 31

How many time constants are necessary for 95% of the tidal volume (V_T)to be delivered from a mechanical ventilator?

A) 1
B) 2
C) 3
D) 4

Question 32

The statement that describes the alveolus shown in Figure 1-1 is which of the following?
1)Requires more time to fill than a normal alveolus
2)Fills more quickly than a normal alveolus
3)Requires more volume to fill than a normal alveolus
4)More pressure is needed to achieve a normal volume

A) 1 and 3 only
B) 2 and 4 only
C) 2 and 3 only
D) 1,3 and 4

Question 33

Calculate the static compliance (C_S),in mL/cm H₂O,when PIP is 47 cm H₂O,plateau pressure (P_plateau)is 27 cm H₂O,baseline pressure is 10 cm H₂O,and exhaled tidal volume (V_T)is 725 mL.

A) 43 C_S
B) 36 C_S
C) 20 C_S
D) 0.065 C_S

Question 34

The transairway pressure (P_TA)shown in this figure is which of the following?

A) 5 cm H₂O
B) 10 cm H₂O
C) 20 cm H₂O
D) 30 cm H₂O

Question 35

What type of ventilator increases transpulmonary pressure (P_L)by mimicking the normal mechanism for inspiration?

A) Positive pressure ventilation (PPV)
B) Negative pressure ventilation (NPV)
C) High frequency oscillatory ventilation (HFOV)
D) High frequency positive pressure ventilation (HFPPV)