Deck 52: Discontinuing Ventilatory Support

Question 1

Which of the following patients exhibits an acceptable ventilatory demand? V_E PaCO₂

A) 12 60
B) 10 55
C) 8 45
D) 6 60

Answer 1

C

Question 2

Which of the following factors will increase ventilatory demand (workload)?
1) Severe hypoxemia
2) Pulmonary infection
3) Increased compliance
4) Bronchospasm

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

Answer 2

B

Question 3

Which of the following oxygenation measures support a patient's readiness to wean?
1) PaO₂/PAO₂ (a/A) = 0.45
2) PaO₂/FiO₂ (P/F) = 110
3) PAO₂ - PaO₂ = 240 mm Hg
4) Physiologic shunt (Q_s/Q_t) = 12%

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

Answer 3

D

Question 4

You measure the spontaneous rate of breathing and V_T on four patients receiving ventilator support. For which one is successful weaning most likely? Breathing frequency V_T

A) 42 250 ml
B) 22 400 ml
C) 22 350 ml
D) 20 200 ml

Answer 4

B

Question 5

Which of the following signs observed on a mechanically ventilated patient indicate that successful weaning is unlikely?
1) Palpable scalene muscle use during inspiration
2) Palpable abdominal tensing during expiration
3) Presence of an irregular breathing pattern
4) Patient unable to alter breathing pattern on command

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

Question 6

When is ventilator dependence likely to occur?
1) When ventilatory capacity exceeds demand
2) When arterial hypoxemia is present
3) When the patient is malnourished
4) When the cardiovascular system is unstable

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

Question 7

Which of the following is false about the P_0.1 measure?

A) P_0.1 correlates well with central respiratory drive.
B) P_0.1 is the airway pressure measured 100 msec after occlusion.
C) P_0.1 is an effort-dependent measure of respiratory drive.
D) Chronic obstructive pulmonary disease (COPD) patients with a P_0.1 greater than 6 cm H₂O are difficult to wean.

Question 8

Which of the following indicate that an adult patient is ready to be weaned from ventilatory support?
1) PAO₂ - PaO₂ = 430 on 100% O₂
2) V_D/V_T = 0.55
3) MIP = -33 cm H₂O
4) PO₂ = 76 mm Hg on 40% O₂

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

Question 9

A patient has an adequate ventilatory reserve if which of the following is true?

A) Ability to double the resting minute ventilation
B) Normal PaCO₂ and minute ventilation less than 10 L/min
C) MIP = -55 cm H₂O
D) V_D/V_T less than 0.4

Question 10

Which of the following metabolic factors can hinder weaning?
1) Excessive carbohydrate feeding
2) Amino acid-based parenteral nutrition
3) Calorie intake = 1.5 . resting energy expenditure (REE)

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

Question 11

Which of the following indicate that a patient's renal function is adequate for weaning?
1) Urine output = 20 ml/hr
2) No major weight gain
3) No edema present
4) Normal electrolytes

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

Question 12

Which of the following four adult patients receiving ventilatory support is the best candidate for weaning? VC V_E MVV MIF V_D/V_T

A) 12 8 22 -22 0.58
B) 8 8 22 -15 0.40
C) 20 12 18 -22 0.60
D) 12 12 18 -10 0.40

Question 13

Successful weaning is less likely when a patient's work of breathing exceeds what level?

A) 4 J/min
B) 8 J/min
C) 12 J/min
D) 16 J/min

Question 14

Which of the following indicate that an adult patient is ready to be weaned from ventilatory support?
1) VC = 1.9 L
2) Spontaneous rate of 32/min
3) Q_s/Q_t = 8%
4) MIP = -45 cm H₂O

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

Question 15

Which of the following factors can reduce a patient's ventilatory drive?
1) Respiratory alkalosis
2) Metabolic acidosis
3) Depressant drugs
4) Decreased metabolism

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

Question 16

Ventilatory capacity is determined by which of the following?
1) Central nervous system (CNS) drive
2) Trigger level
3) Muscle strength
4) Muscle endurance

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

Question 17

What is the most important prerequisite for weaning a patient from ventilatory support?

A) Improvement in the original problem requiring mechanical ventilation
B) Assurance that the patient's ventilatory demand exceeds the patient's capacity
C) Objective evidence indicating good respiratory muscle endurance
D) Ability to maintain adequate oxygenation with an FiO₂ less than 0.4

Question 18

Above what pressure-time index (PTI) will most patients be unable to sustain spontaneous breathing?

A) 0.03
B) 0.05
C) 0.10
D) 0.15

Question 19

A patient receiving ventilator support has a spontaneous rate of breathing of 26/min and an average V_T of 300 ml. What is this patient's rapid-shallow breathing index?

A) 12
B) 87
C) 105
D) 66

Question 20

What is the least reliable weaning index?

A) Vital capacity (VC)
B) Maximum inspiratory capacity (MIP)
C) Minute ventilation (V_E)
D) Rapid-shallow breathing index (f/V_T)

Question 21

Which method of weaning may be useful to minimize auto-PEEP?

A) Intermittent mandatory ventilation
B) Intermittent mandatory ventilation
C) Continuous positive airway pressure
D) T-piece

Question 22

Which of the following health care disciplines should be involved in the care of a patient who is considered difficult to wean?
1) Physical therapy
2) Speech therapy
3) Social services
4) Occupational therapy

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

Question 23

Which of the following cardiovascular signs would indicate that a patient's cardiovascular status is unstable and that weaning should not begin at this time?

A) Cardiac index of 2.5 L/min/m²
B) Hemoglobin content of 10 g/dl
C) Heart rate of 108/min
D) Systolic blood pressure of 80 mm Hg

Question 24

Which of the following must you verify when considering weaning an obtunded patient?
1) Adequate gag reflex
2) No depressant drugs
3) Adequate cough

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

Question 25

What are some advantages of mandatory minute ventilation (MMV) as a weaning tool?
1) It provides greater control over PaCO₂ than intermittent mandatory ventilation does.
2) It prevents acidemia with acute hypoventilation.
3) It eliminates concerns over depressant drugs.
4) It ensures an efficient pattern of ventilation.

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

Question 26

An alert patient receiving ventilatory support through a demand flow intermittent mandatory ventilation system exhibits clinical signs of an increased work of breathing whenever you try to decrease the mandatory rate below 6/min. In order to aid in weaning this patient, which of the following would you recommend?

A) Apply a low level of pressure support.
B) Apply a high level of inspiratory pressure.
C) Increase the mandatory V_T.
D) Decrease the mandatory V_T.

Question 27

Prerequisites for successful weaning include:
1) psychological readiness.
2) adequate gag and swallow reflexes.
3) ability to follow instructions.
4) adequate cough.

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

Question 28

Which of the following drug categories can depress ventilatory drive and hinder weaning?
1) Analgesics
2) Narcotics
3) Hypnotics
4) Antibiotics

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

Question 29

Which of the following techniques can help to decrease a patient's imposed work of breathing during weaning from ventilatory support?
1) Use of pressure-supported ventilation (PSV)
2) Trigger breath by flow, not pressure
3) Application of small amounts of continuous positive airway pressure (CPAP) or positive end expiratory pressure (PEEP)
4) Use of automatic tube compensation (ATC)

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

Question 30

Which of the following ventilator strategies would you consider as a good alternative to T tube trials when using a rapid weaning protocol?
1) Continuous positive airway pressure (CPAP) with flow-by (flow triggering)
2) Low-level pressure-supported ventilation (PSV)
3) Intermittent mandatory ventilation

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

Question 31

Advantages of adding continuous positive airway pressure (CPAP) to T tube weaning include which of the following?
1) Improved blood oxygenation
2) Decreased work of breathing
3) Compensation for auto-PEEP
4) Faster weaning or extubation

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

Question 32

Common approaches used to wean patients from ventilatory support include which of the following?
1) T tube alternating with mechanical ventilation
2) Pressure-supported ventilation (PSV)
3) Intermittent mandatory ventilation

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

Question 33

A physician is using a pressure support protocol to wean a patient off ventilatory support. The patient is now at a 5 cm H₂O pressure level and has a spontaneous respiratory rate of 21/min. Other cardiovascular and respiratory signs indicate that the patient remains stable. Which of the following actions would you recommend at this point?

A) Switch the patient to 5 cm H₂O continuous positive airway pressure (CPAP) through the endotracheal tube.
B) Extubate the patient and provide supplemental O₂.
C) Switch the patient to intermittent mandatory ventilation at a rate of 2/min.
D) Decrease the pressure support level to 3 cm H₂O.

Question 34

Which of the following ventilator modes can ensure delivery of a preset V_T during spontaneous breathing?
1) Volume support
2) Volume-assured pressure support
3) Mandatory minute ventilation

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

Question 35

An alert patient receiving intermittent mandatory ventilation at a rate of 8/min and V_T of 600 ml has stable vital signs and satisfactory blood gases on an FiO₂ of 0.45. What would you do to initiate weaning for this patient?

A) Lengthen the automatic sigh interval.
B) Decrease the mandatory rate to 5 to 6/min.
C) Increase FiO₂ to 60%.
D) Decrease the V_T to 500 ml.

Question 36

In most weaning protocols, what minimum blood gas parameters are needed to start the process?

A) PaO₂ greater than 70 mm Hg and PaCO₂ less than 50 mm Hg on FiO₂ less than 0.6 and PEEP less than 5 cm H₂O
B) PaO₂ greater than 70 mm Hg and PaCO₂ less than 50 mm Hg on FiO₂ less than 0.4 and PEEP 5 cm H₂O or greater
C) PaO₂ greater than 50 mm Hg and PaCO₂ less than 50 mm Hg on FiO₂ less than 0.6 and PEEP less than 10 cm H₂O
D) PaO₂ greater than 70 mm Hg and PaCO₂ less than 70 mm Hg on FiO₂ less than 0.6 and PEEP 5 cm H₂O or greater

Question 37

A physician orders a T tube trial for a patient receiving ventilatory support in the assist-control mode with an FiO₂ of 0.4. What FiO₂ would you recommend for this patient during the spontaneous breathing period?

A) 0.3
B) 0.4
C) 0.5
D) 0.6

Question 38

Which of the following electrolyte imbalances can hinder weaning from ventilatory support?
1) Hypochloremia
2) Hypomagnesemia
3) Hypokalemia
4) Hyponatremia

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

Question 39

A physician has selected a pressure support protocol to wean a patient off ventilatory support. Which of the following pressure levels would you recommend to begin the weaning process?

A) Pressure sufficient to obtain a V_T of 3 to 5 ml/kg of predicted body weight (PBW)
B) Pressure sufficient to overcome the imposed workload
C) Pressure sufficient to obtain a V_T of 4 to 8 ml/kg PBW
D) Pressure equal to 30% of the volume-cycled peak inspiratory pressure

Question 40

Which of the following is false about noninvasive positive-pressure ventilation (NIV)?

A) NIV can support ventilation without a tracheal airway.
B) NIV should not be used with patients at risk for aspiration.
C) Patients likely to fail weaning are good candidates for NIV.
D) NIV can be used to prevent reintubation when weaning fails.

Question 41

Which of the following weaning methods provides the best respiratory muscle strength conditioning?

A) Pressure-supported ventilation
B) T tube
C) Intermittent mandatory ventilation
D) Volume-assured pressure support

Question 42

What patients are at high risk for postextubation upper airway obstruction?
1) Those with neuromuscular disorders
2) Those who have had major neck surgery
3) Those with infectious masses or abscesses

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

Question 43

Which of the following cardiovascular changes would you consider a bad sign during weaning a patient from ventilatory support?

A) Development of chest pain
B) Increase in both stroke volume and cardiac index
C) Increase in heart rate from 95 to 110/min
D) Fall in blood pressure from 143/95 to 126/88 mm Hg

Question 44

While monitoring a patient during a T tube weaning trial, you notice the following: increased patient agitation; increased heart rate (from 90 to 118/min); increased respiratory rate (from 17 to 33/min with some paradoxical motion); and premature ventricular contractions (PVCs) increasing to an average of 5/min. Which of the following actions would be appropriate at this time?

A) Reconnect the patient to the ventilator with prior settings.
B) Encourage the patient to relax, and continue careful monitoring.
C) Request that the patient be given a stat (immediate) bolus of lidocaine.
D) Request that the patient be given a strong sedative or hypnotic.

Question 45

In considering a patient for endotracheal tube extubation, which of the following procedures would you recommend to determine the risk of postextubation upper airway obstruction?

A) Methylene blue test
B) Pre- and postbronchodilator
C) Cuff leak test
D) Forced vital capacity

Question 46

What is the best way to decrease the work of breathing imposed by an artificial airway on a patient receiving ventilatory support?

A) Provide pressure support.
B) Decrease inspiratory flow.
C) Lower the minute ventilation.
D) Use low rates of breathing.

Question 47

While monitoring a patient being weaned through a T tube protocol, signs indicating that mechanical ventilation should be restored include which of the following?
1) Development of cardiac arrhythmias
2) Asynchronous or paradoxical breathing
3) Development of severe hypotension
4) Moderate rise in respiratory rate

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

Question 48

Which of the following are useful strategies in managing the psychological problems encountered in weaning some patients from ventilator support?
1) Secure a psychiatric consult.
2) Decrease environmental stress.
3) Avoid mental stimulation.
4) Teach relaxation methods.

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

Question 49

Which of the following are advantages of using pressure-supported ventilation for weaning?
1) Guaranteed V_T
2) Reduced work of breathing
3) Respiratory muscle fatigue prevented
4) Better patient comfort and synchrony

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

Question 50

Which of the following is false about artificial tracheal airways and weaning?

A) There are decreases in tube inner diameter (ID) and increases in V_E increase the work of breathing.
B) The added work due to artificial airways can increase ventilator dependence.
C) Artificial airways can increase the work of breathing nearly three-fold.
D) Tracheostomy tubes increase the work of breathing more than can endotracheal tubes.

Question 51

In an effort to determine a patient's need for ventilatory support, which of the following factors increase(s) ventilatory workload?
1) Decreased lung compliance
2) Decreased thoracic compliance
3) Increased airway resistance
4) Artificial airways

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

Question 52

Which of the following are disadvantages of using the T tube method for weaning?
1) More staff time required
2) Abrupt transition sometimes difficult
3) High imposed work of breathing
4) Lack of alarm systems

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

Question 53

While monitoring a patient during a T tube weaning trial, you notice the following: an increase in heart rate from 86 to 100/min; an increase in respiratory rate from 12 to 23/min; an increase in PaCO₂ from 39 to 45 mm Hg; and a decrease in PaO₂ from 82 to 73 mm Hg. Which of the following actions would be appropriate at this time?

A) Reconnect the patient to the ventilator with prior settings.
B) Request that the patient be administered a mild sedative.
C) Suction the patient after manual hyperinflation or oxygenation.
D) Encourage the patient to relax, and continue careful monitoring.

Question 54

Which of the following are disadvantages of using intermittent mandatory ventilation for weaning?
1) Potentially high work of breathing
2) Weaning time possibly prolonged
3) Patient-ventilator asynchrony
4) Higher mean airway pressures

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

Question 55

Which of the following patients are at high risk for severe laryngeal edema after an endotracheal tube extubation?
1) Pediatric burn victim
2) Patient with epiglottitis
3) Smoke inhalation patient
4) Pulmonary fibrosis patient

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

Question 56

A patient whom you are trying to wean below 5 cm H₂O pressure support develops respiratory muscle fatigue. Which of the following would you recommend to overcome this problem?
1) Make sure there is adequate O₂ transport or cardiac output.
2) Make sure that the patient is adequately nourished.
3) Check and replace any depleted electrolytes.
4) Clear secretions and provide bronchodilation.

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

Question 57

Which of the following changes can be expected when weaning a patient through a T tube trial?
1) Increase in respiratory rate of 10/min
2) Increase in heart rate of 15 to 20/min
3) 5 to 10 mm Hg rise in the arterial PCO₂
4) Doubling of the minute ventilation

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

Question 58

What are some factors that indicate a patient's readiness for extubation?
1) Adequate oxygenation or ventilation with spontaneous breathing
2) Minimal risk for upper airway obstruction
3) Adequate airway protection or minimal aspiration risk
4) Adequate clearance of pulmonary secretions

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

Question 59

Who should make the decisions related to terminal weaning?

A) Patient
B) Patient's family and patient's physician
C) Nurse
D) Respiratory therapist

Question 60

Which factors lead to the development of computer-based weaning protocols?
1) Respiratory therapists are unable to successfully wean most patients using protocols.
2) Computer-based weaning protocols are relatively easy to develop.
3) Weaning is time-consuming.
4) Weaning is a labor-intensive process.

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

Question 61

The physician has requested that the respiratory therapist determine a patient's rapid shallow breathing index (RSBI) before placing the patient on PSV. The patient has a respiratory rate of 32/min and VT of 300 ml. What is the patient's RSBI?

A) 107
B) 110
C) 112
D) 114