Deck 12: Introduction to Ventilators

Question 1

An open-loop ventilator system can be described as which of the following?

A) Feedback
B) Hierarchical
C) Unintelligent
D) Servo-controlled

Answer 1

C
Unintelligent ventilators are called open-loop systems because they do not respond to changes in the delivery of gas to the patient when there are any problems.

Question 2

A closed-loop ventilator system can be described as which of the following?
1)Feedback
2)Hierarchical
3)Unintelligent
4)Servo-controlled

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

Answer 2

C
A closed-loop ventilator system is an intelligent system that can respond to certain inputs based on programming.This type of system is similar to cruise control on a car.When a parameter is set on the ventilator,the ventilator compares the input with the output and makes certain adjustments.These systems are also called feedback or servo-controlled systems.

Question 3

The main parameter that the ventilator manipulates for any given breath is referred to as which of the following?

A) Control circuit
B) Phase variable
C) Control variable
D) Cycle variable

Answer 3

C
The main parameter or variable controlled by the ventilator for any given breath is referred to as the control variable.A control circuit is part of the internal circuit of a mechanical ventilator and consists of mechanical devices,such as spring-loaded valves,pneumatic systems,or fluidic components.Phase variables are the variables that control the four phases of a breath.A cycle variable is the variable that is being used by the ventilator to end inspiration.

Question 4

The Downs continuous positive airway pressure system uses which of the following to establish positive airway pressure?

A) Weighted ball
B) Magnetic valve
C) Spring-loaded valve
D) Opposing gas flow

Question 5

Which of the following variables ends the inspiratory phase?

A) Cycle
B) Limit
C) Trigger
D) Sensitivity

Question 6

Which of the following is a device that uses a flow resistor to create expiratory pressure?

A) Positive expiratory pressure mask
B) Downs continuous positive airway pressure generator
C) Modern ventilator
D) Fluidic device

Question 7

A separation bubble in a fluidic device does which of the following?

A) Causes a flip-flop to occur
B) Causes a high-pressure vortex
C) Bends the gas jet stream toward the wall
D) Pushes the gas jet stream away from the wall

Question 8

The set tidal volume is 500 mL.During the first breath,the exhaled volume measures 390 mL,with a peak pressure of 18 cm H₂O.The second breath returns 460 mL,with 20 cm H₂O.The third breath has a peak pressure of 22 cm H₂O,with an exhaled volume of 500 mL.This can be described as what type of system?

A) Open-loop
B) Closed-loop
C) Single-circuit
D) Double-circuit

Question 9

Which of the following flow-controlling valves operates by using the principles of electromagnetism?

A) Poppet
B) Stepper motor
C) Proportional solenoid
D) Microprocessor-operated

Question 10

The gas that enters the ventilator from high-pressure sources goes directly to the patient.This is a description of a _____ system.

A) single-circuit
B) double-circuit
C) pneumatic circuit
D) power transmission

Question 11

An iron lung is which type of ventilator?

A) Fluidic
B) Positive-pressure
C) Negative-pressure
D) Positive/negative pressure

Question 12

A patient is receiving a continuous positive airway pressure of 10 cm H₂O via mask from a Downs continuous positive airway pressure generator.During each inspiration,the pressure manometer decreases to 3 cm H₂O.The patient is diaphoretic,tachypneic,and tachycardic. To correct this situation,the respiratory therapist should do which of the following?

A) Increase the gas flow
B) Increase the pressure
C) Tighten the fit of the mask
D) Replace the spring-loaded valve

Question 13

A patient is receiving continuous positive airway pressure from a freestanding,continuous-flow system.The respiratory therapist notices the pressure-release valve venting on each patient exhalation.What action should the respiratory therapist take?

A) Replace the continuous positive airway pressure device
B) Decrease the flow rate
C) Increase the pressure level
D) Remove the pressure-release valve

Question 14

What variable begins the inspiratory phase of a ventilator?

A) Cycle
B) Limit
C) Control
D) Trigger

Question 15

The function of the exhalation valve in the external circuit is to do which of the following?

A) Deflate during inspiration to allow the gas to go to the patient
B) Inflate during inspiration to prevent leaks in the inspiratory circuit
C) Inflate during inspiration to divert gas coming from the ventilator into the patient
D) Inflate during expiration to allow the patient to exhale through the expiratory line

Question 16

Which two of the following basic physical principles are used in the power transmission design of fluidic ventilators?
1)Venturi
2)Bernoulli
3)Beam deflection
4)Wall attachment

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

Question 17

Which of the following is the flow waveform created by a linear-drive piston?

A) Sinusoidal
B) Rectangular
C) Ascending ramp
D) Descending ramp

Question 18

Which type of ventilator creates a sinusoidal pressure waveform pattern of positive and negative pressures?

A) Fluidic
B) Pneumatic
C) Positive-pressure
D) Combined-pressure

Question 19

A patient receiving continuous positive airway pressure of 7.5 cm H₂O via a mask and freestanding system appears to be in distress.The patient is using accessory muscles and is diaphoretic. The manometer is fluctuating between -5 cm H₂O on inspiration and 7.5 cm H₂O on expiration.The most apparent cause of the patient's distress is which of the following?

A) Leak in the system
B) Improper mask fitting
C) Inadequate flow rate
D) Obstruction of the threshold resistor

Question 20

Pneumatic ventilators may incorporate which of the following components for operation?
1)Pistons
2)Air entrainers
3)Flexible diaphragms
4)Internal direct current batteries

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

Question 21

Which of the following variables begins a mandatory breath?

A) Flow
B) Time
C) Volume
D) Pressure

Question 22

Which of the following represents the amount of time for a pressure-targeted ventilator breath to reach the set pressure?

A) Rise time
B) Inspiratory time
C) Total cycle time
D) Inspiratory hold

Question 23

On a mechanical ventilator,pressure triggering is usually set within which of the following ranges?

A) -0.5 to -1.5 cm H₂O
B) -2.0 to 0.5 cm H₂O
C) 0.5 to 2.0 cm H₂O
D) 1.0 to 3.0 cm H₂O

Question 24

The flow,volume,and pressure waveforms characteristic of a pressure-limited,time-cycled breath are represented in which column of the figure?

A) A
B) B
C) C
D) D

Question 25

The maximum safety pressure should be set at _____ cm H₂O when the peak pressure reached during volume-controlled ventilation is 25 cm H₂O.

A) 30
B) 35
C) 40
D) 45

Question 26

Which of the following variables cannot be exceeded during inspiration?

A) Limit
B) Cycle
C) Safety
D) Trigger

Question 27

Which two of the following patient triggers are most common?
1)Flow
2)Neural
3)Volume
4)Pressure

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

Question 28

The figure shows the pressure-time scalar for a pressure-support breath.To alleviate the problem depicted in this figure,the respiratory therapist should do which of the following?

A) Decrease the pressure setting
B) Increase the inspiratory time
C) Add inspiratory sloping
D) Decrease the set volume

Question 29

When the maximum safety pressure setting on an adult ventilator is reached,which of the following occurs?

A) Inspiration is triggered.
B) Flow begins to decrease.
C) Inspiration ends prematurely.
D) Pressure is held until the target volume is delivered.

Question 30

What is the flow rate if the set volume is 550 mL and the inspiratory time is 1.2 second?

A) 27.5 L/min
B) 45.8 L/min
C) 55 L/min
D) 66 L/min

Question 31

Decreased lung compliance during pressure-limited ventilation would cause which of the following?

A) Increased flow rates
B) Increased pressure delivery
C) Decreased volume delivery
D) Decreased inspiratory pressures

Question 32

Improving lung compliance during volume-controlled ventilation would cause a(n)_____ in peak _____.

A) decease; pressure
B) increase; pressure
C) decrease; flow rate
D) increase; flow rate

Question 33

If the base flow is 8 L/min and the flow-trigger setting is 3 L/min,at what flow rate would the ventilator be triggered?

A) 3 L/min
B) 5 L/min
C) 8 L/min
D) 11 L/min

Question 34

The flow,volume,and pressure waveforms characteristic of volume breaths with a sine-like flow pattern are shown in which column of the figure?

A) A
B) B
C) C
D) D

Question 35

With a baseline pressure setting of 6 cm H₂O and a sensitivity setting of -1.5 cm H₂O,inspiration will begin at _____ cm H₂O.

A) -1.5
B) -4.5
C) +1.5
D) +4.5

Question 36

The pressure maintained at the airway during exhalation is known as which of the following?

A) Baseline
B) Proximal
C) Sensitivity
D) Mean airway

Question 37

If the base flow is 10 L/min and the flow-trigger setting is 4 L/min,the flow during the expiratory phase is _____ L/min.

A) 4
B) 6
C) 10
D) 14

Question 38

The flow,volume,and pressure waveforms characteristic of volume breaths with a constant flow are shown in which column of the figure?

A) A
B) B
C) C
D) D

Question 39

The flow,volume,and pressure waveforms characteristic of volume breaths with a descending ramp flow pattern are shown in which column of the figure?

A) A
B) B
C) C
D) D

Question 40

When the maximum safety pressure on a volume ventilator is reached,which of the following occurs?

A) The flow rate begins to taper.
B) Pressure is held until the time cycle is reached.
C) Pressure is held until the ventilator volume cycles.
D) Inspiration ends before the entire volume is delivered.

Question 41

What is the transairway pressure from the information found in the figure?

A) 10 cm H₂O
B) 15 cm H₂O
C) 25 cm H₂O
D) 35 cm H₂O

Question 42

What is the static lung compliance when the returned tidal volume is 460 mL,the positive end-expiratory pressure is 8 cm H₂O,the peak inspiratory pressure is 27 cm H₂O,and the plateau pressure is 18 cm H₂O?

A) 20 mL/cm H₂O
B) 26 mL/cm H₂O
C) 46 mL/cm H₂O
D) 51 mL/cm H₂O

Question 43

What is the compressibility factor for the patient circuit when the ventilator volume is set at 100 mL,the recorded peak inspiratory pressure is 41 cm H₂O,and the measured volume is 68 mL?

A) 0.41 cm H₂O/mL
B) 0.60 cm H₂O/mL
C) 1.66 mL/cm H₂O
D) 2.44 mL/cm H₂O

Question 44

What is the static lung compliance when the returned tidal volume is 700 mL,the positive end-expiratory pressure is 10 cm H₂O,the peak inspiratory pressure is 45 cm H₂O,and the plateau pressure is 35 cm H₂O?

A) 0.160 L/cm H₂O
B) 0.020 L/cm H₂O
C) 0.028 L/cm H₂O
D) 0.735 L/cm H₂O

Question 45

Worsening lung compliance during volume-controlled ventilation would cause which of the following?

A) A decrease in peak pressure
B) An increase in peak pressure
C) A decrease in volume delivery
D) An increase in peak flow rate

Question 46

What is the compressibility factor for the patient circuit when the ventilator volume is set at 200 mL,the recorded peak inspiratory pressure is 72 cm H₂O,and the measured volume is 148 mL?

A) 0.36 cm H₂O/mL
B) 0.49 cm H₂O/mL
C) 2.06 mL/cm H₂O
D) 2.78 mL/cm H₂O

Question 47

Pressure-support ventilation is classified as:
1)Flow cycled
2)Time triggered
3)Volume targeted
4)Pressure targeted
5)Patient triggered

A) 2 and 3
B) 4 and 5
C) 1,4,and 5
D) 1,2,and 3

Question 48

Worsening lung compliance during pressure-controlled ventilation would cause which of the following?

A) A decrease in peak pressure
B) An increase in peak pressure
C) A decrease in volume delivery
D) An increase in peak flow rate

Question 49

What is the volume that will reach the patient when the volume setting is 700 mL,the tubing compliance is 2 mL/cm H₂O,and the measured peak inspiratory pressure is 35 cm H₂O?

A) 770 mL
B) 698 mL
C) 665 mL
D) 630 mL

Question 50

During volume ventilation,peak inspiratory pressure is the pressure needed to overcome which two of the following factors?
1)Muscle pressure
2)Airflow resistance
3)Elastic recoil pressure
4)Transthoracic pressure

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

Question 51

Increasing the functional residual capacity of a spontaneously breathing patient to improve oxygenation can be accomplished by which of the following?

A) Inspiratory plateau
B) Positive end-expiratory pressure
C) Negative end-expiratory pressure
D) Continuous positive airway pressure

Question 52

Plateau pressure may be obtained during volume ventilation by using which of the following?

A) Expiratory pause
B) Inspiratory pause
C) End-expiratory pressure
D) Increased inspiratory time

Question 53

During pressure-targeted ventilation with a set pressure of 24 cm H₂O,the patient coughs.The ventilator responds by in which of the following ways?

A) Inspiration ends immediately.
B) Inspiratory time increases.
C) Inspiration continues with the set pressure.
D) Inspiratory pressure ends at the maximum safety pressure.

Question 54

What is the static lung compliance when the returned tidal volume is 500 mL,the baseline pressure is zero,and the plateau pressure reading is 25 cm H₂O?

A) 0.02 L/cm H₂O
B) 2.0 L/cm H₂O
C) 0.2 L/cm H₂O
D) 2.0 L/cm H₂O

Question 55

Increased transairway pressure is associated with which two of the following changes?
1)Increased airway resistance
2)Decreased airway resistance
3)Increased static compliance
4)Decreased static compliance

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

Question 56

Which of the following is the formula for transairway pressure?

A) Peak inspiratory pressure - Plateau pressure
B) Plateau pressure - Peak inspiratory pressure
C) Positive end-expiratory pressure - Plateau pressure
D) Peak inspiratory pressure - Positive end-expiratory pressure

Question 57

Which of the following flow-termination settings for a pressure-supported breath that has a peak inspiratory flow of 30 L/min would allow enough time for a visible plateau on the pressure-time curve?

A) 5 L/min
B) 20 L/min
C) 20% of peak flow
D) 30% of peak flow

Question 58

Improving lung compliance during pressure-controlled ventilation would cause which of the following?

A) A decrease in peak pressure
B) An increase in peak pressure
C) An increase in volume delivery
D) A decrease in volume delivery

Question 59

The transairway pressure represents the pressure associated with which of the following?

A) Elastic recoil
B) Airflow resistance
C) Tubing compressibility
D) End-expiratory pressure

Question 60

How much volume is lost in the ventilator circuit when the volume is set at 500 mL,the peak inspiratory pressure is 40 cm H₂O,and the tubing compliance is 3 mL/cm H₂O?

A) 380 mL
B) 280 mL
C) 150 mL
D) 120 mL

Question 61

What procedure is used to estimate the amount of air trapped in the patient's lungs and in the patient circuit?

A) Inspiratory pause
B) End-expiratory pause
C) Pressure-control ventilation
D) Pressure-release ventilation

Question 62

Mandatory breaths during pressure-controlled mechanical ventilation (pressure-controlled continuous mandatory ventilation)are cycled into expiration by which of the following?

A) Time
B) Flow
C) Volume
D) Pressure

Question 63

The pressure support level is automatically adjusted by the ventilator to maintain appropriate breathing frequency,tidal volume,and end-tidal carbon dioxide,depending on the patient's pathologic condition.This mode description pertains to which of the following ventilator control types?

A) Adaptive
B) Set-point
C) Knowledge-based
D) Neurally adjusted ventilatory assist

Question 64

The description "a mode where each breath is pressure limited and the pressure-limit level is adjusted automatically between breaths by using ventilatory mechanics to minimize the patient's work of breathing" pertains to which ventilator control type?

A) Servo
B) Optimal
C) Adaptive
D) Auto-set-point

Question 65

Auto-PEEP can be detected without the use of an expiratory pause on which of the following curves?

A) Pressure-time
B) Flow-time
C) Pressure-volume
D) Volume-time

Question 66

Which of the following represents the safe starting point for pressure support of a patient just placed on volume-controlled intermittent mandatory ventilation with the following set and measured parameters: tidal volume,475 mL; peak inspiratory pressure,30 cm H₂O; plateau pressure,10 cm H₂O; and flow rate,45 L/min?

A) 4 cm H₂O
B) 7 cm H₂O
C) 20 cm H₂O
D) 27 cm H₂O

Question 67

Which of the following is the technique that can actively remove gas from a ventilator circuit at the beginning of expiration?

A) Expiratory pause
B) Inspiratory pause
C) Positive end-expiratory pressure
D) Negative end-expiratory pressure

Question 68

Which of the following control modes of ventilation consists of ventilator output automatically following a varying input (e.g.,volume or flow generated by the patient)?

A) Servo
B) Optimal
C) Neural network
D) Knowledge-based

Question 69

Which of the following ventilator modes decreases the effect of airway resistance on the patient's spontaneous breathing?

A) Pressure-support ventilation
B) Pressure-controlled continuous mandatory ventilation
C) Volume-controlled intermittent mandatory ventilation
D) Volume-controlled continuous mandatory ventilation

Question 70

Adult candidates for pressure-support ventilation include patients with which of the following?
1)Nasotracheal tube
2)Minute ventilation <10 L
3)Spontaneous tidal volume <100 mL
4)Spontaneous respiratory rate >20 breaths/min

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

Question 71

Which of the following is a mode of ventilation that is time triggered or patient triggered as well as pressure limited and time cycled?

A) Pressure-support ventilation
B) Pressure-controlled intermittent mandatory ventilation
C) Pressure-controlled continuous mandatory ventilation
D) Dual control continuous mandatory ventilation

Question 72

Which of the following ventilator modes is recommended for patients who have intact respiratory centers and who are breathing spontaneously?

A) Intermittent mandatory ventilation
B) Pressure-support ventilation
C) Pressure-controlled ventilation
D) Continuous mandatory ventilation

Question 73

The mandatory breath begins as a pressure-controlled breath,but it switches to volume control during inspiration because a preset volume is not achieved. This describes which of the following control types?

A) Set-point
B) Adaptive
C) Auto-set-point
D) Knowledge-based

Question 74

The ventilator mode that is either patient triggered or time triggered and allows the patient to breathe spontaneously between mandatory ventilator breaths is known as:

A) Pressure-support ventilation
B) Pressure-controlled ventilation
C) Intermittent mandatory ventilation
D) Continuous mandatory ventilation

Question 75

What does point A represent on the pressure-time scalar shown in the figure?

A) Plateau pressure
B) Maximum safety pressure
C) Positive end-expiratory pressure
D) Auto-PEEP

Question 76

Which of the following control modes of ventilation consists of pressure-limited mandatory breaths that can be automatically adjusted between breaths to achieve a preset tidal volume?

A) Servo
B) Optimal
C) Adaptive
D) Auto-set-point

Question 77

Which of the following ventilator control types consists of the output of the ventilator automatically matching a constant operator-preset input value?

A) Optimal
B) Set-point
C) Auto-set-point
D) Knowledge-based

Question 78

Which of the following is a ventilator mode that allows the ventilator to switch from pressure control to volume control or vice versa?

A) Dual-control mode
B) Flow-control mode
C) Volume-control mode
D) Pressure-control mode

Question 79

Which of the following statements is true concerning mechanical ventilation classification?

A) The names for modes of ventilation are current and accurate.
B) Mode classification should be individualized by manufacturers.
C) Mode classification terminology needs to be clearly defined.
D) All manufacturer mode terminology adheres to Chatburn's system.

Question 80

A dual mode that features a pressure-controlled breath pattern with volume as a conditional variable is which of the following?

A) Tactical control ventilation
B) Pressure-targeted ventilation
C) Pressure-regulated volume control
D) Volume-regulated pressure control