Deck 44: Respiratory Failure and the Need for Ventilatory Support

Question 1

Which of the following could cause hypercapnic respiratory failure?
1) Smoke inhalation
2) Opiate drug overdose
3) Chronic obstructive pulmonary disease
4) Hypothyroidism

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

Answer 1

D

Question 2

Which of the following clinical signs is most often associated with hypoxemia due to shunt?

A) Diffuse wheezing
B) "White" chest radiograph
C) Stridor
D) Loud P2

Answer 2

B
Explanation: Shunt usually presents with a "white" chest radiograph.

Question 3

Hypercapnic (type II) respiratory failure is a synonym for which one of the following terms?

A) Mismatching
B) Shunt
C) Diffusion impairment
D) Ventilatory failure

Answer 3

D
Explanation: Hypercapnic respiratory failure is also known as ventilatory failure.

Question 4

What happens to the P(A-a)O₂ with mismatch and shunt?

A) It increases withmismatch and decreases with shunt.
B) It decreases with bothmismatch and shunt.
C) It increases with bothmismatch and shunt.
D) It does not change.

Question 5

A patient with an opiate drug overdose is unconscious and exhibits the following blood gas results breathing room air: pH = 7.19; PCO₂ = 89; HCO₃^- = 27; PO₂ = 48. Which of the following best describes this patient's condition?

A) Chronic hypoxemic respiratory failure
B) Chronic hypercapnic respiratory failure
C) Acute hypoxemic respiratory failure
D) Acute hypercapnic respiratory failure

Question 6

Which of the following information best helps to distinguish chronic hypercapnic respiratory failure from acute hypercapnic respiratory failure?

A) Long-standing dyspnea that worsens on exertion
B) Forced expiratory volume in 1 sec to forced vital capacity ratio (FEV₁/FVC) of less than 75% predicted
C) Kidneys retaining bicarbonate to elevate the blood pH
D) Physical signs of hypoxemia, such as cyanosis and clubbing

Question 7

A diagnosis of respiratory failure can be made if which of the following are present?
1) PaO₂ 55 mm Hg, FiO₂ 0.21, P_B 760 mm Hg
2) PaCO₂ 57 mm Hg, FiO₂ 0.21, P_B 760 mm Hg
3) P(A-a)O₂ 45 mm Hg, FiO₂ 1.0, P_B 760 mm Hg
4) PaO₂/FiO₂ 400, P_B 750 mm Hg

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

Question 8

Which of the following are associated with hypercapnic respiratory failure due to respiratory muscle weakness or fatigue?
1) Hyperthyroidism
2) Myasthenia gravis
3) Amyotrophic lateral sclerosis
4) Guillain-Barré syndrome

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 with interstitial lung disease who presents with hypoxemia due to diffusion defect would have which of the following clinical signs?
1) Fine bibasilar crackles
2) Clubbing of the finger nail beds
3) Jugular venous distention
4) Thrombocytopenia

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

Question 10

Which of the following are associated with hypercapnic respiratory failure due to decreased ventilatory drive?
1) Brainstem lesions
2) Encephalitis
3) Hypothyroidism
4) Asthma

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

Question 11

Which of the following is false about the "acute-on-chronic" form of respiratory failure?

A) It usually involves patients with hypoxemic respiratory failure.
B) It is most common in patients with chronic airway obstruction.
C) Bacterial or viral infections are common precipitating factors.
D) Mortality is associated with severity of acidosis.

Question 12

What is the normal P(A-a)O₂ range while breathing room air?

A) 25 to 50 mm Hg
B) 10 to 25 mm Hg
C) Greater than 25 mm Hg
D) Less than 10 mm Hg

Question 13

What is the most common cause of low mixed venous oxygen?

A) Liver disease
B) Cardiac disease
C) Neuromuscular disease
D) Vascular disease

Question 14

What is respiratory failure due to inadequate ventilation?

A) Hypoxemic
B) Hypercapnic
C) Compensated
D) Chronic

Question 15

Which of the following best describes the difference between mismatch and shunt when supplemental oxygen is administered?
a.
Both will respond equally well.
b.
mismatch will respond well but shunt will not.
c.
mismatch will not respond but shunt will respond well.
d.
Neither will respond to the administration of supplemental oxygen.

Question 16

Which of the following can cause hypoxemia?
1) Diffusion impairment
2) Alveolar hypoventilation
3) mismatch
4) Intrapulmonary shunting

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

Question 17

What type of disease is associated with perfusion/diffusion impairment?

A) Liver disease
B) Renal disease
C) Neuromuscular disease
D) Vascular disease

Question 18

What is the optimal treatment of intrapulmonary shunt?

A) Increase the FiO₂.
B) Decrease the FiO₂.
C) Surgery.
D) Alveolar recruitment.

Question 19

Which of the following clinical signs suggest more severe hypoxemia?

A) Tachycardia
B) Cyanosis with polycythemia
C) Central nervous system dysfunction
D) Use of accessory muscles

Question 20

Which of the following indicators are useful in assessing respiratory muscle strength?
1) Maximum voluntary ventilation (MVV)
2) Forced vital capacity (FVC)
3) Dead space-to-tidal volume ratio (V_D/V_T)
4) Maximum inspiratory pressure (MIP)

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

Question 21

Which of the following measures should be used in assessing the adequacy of a patient's alveolar ventilation?
1) PaO₂
2) Arterial pH
3) PaCO₂
4) HCO₃^-

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

Question 22

Which of the following MIP measures taken on an adult patient indicates inadequate respiratory muscle strength?

A) -90 cm H₂O
B) -70 cm H₂O
C) -40 cm H₂O
D) -15 cm H₂O

Question 23

Which of the following measures are useful indicators in assessing the adequacy of a patient's oxygenation?
1) PaO₂-PaO₂
2) PaO₂-to-FiO₂ ratio
3) V_D/V_T
4) Pulmonary shunt

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

Question 24

A patient with a 10-year history of chronic bronchitis and an acute viral pneumonia exhibits the following blood gas results breathing room air: pH = 7.22; PCO₂ = 67; HCO₃^- = 26; PO₂ = 60. Which of the following best describes this patient's condition?

A) Chronic hypoxemic respiratory failure
B) Acute hypercapnic respiratory failure
C) Chronic hypercapnic respiratory failure
D) Acute hypoxemic respiratory failure

Question 25

What is the normal range of maximum inspiratory pressure, or MIP (also called negative inspiratory force, or NIF), generated by adults?

A) -80 to -100 cm H₂O
B) -50 to -80 cm H₂O
C) -30 to -50 cm H₂O
D) -20 to -30 cm H₂O

Question 26

Which of the following measures taken on adult patients indicate unacceptably high ventilatory demands or work of breathing?

A) V_E of 17 L/min
B) Breathing rate of 22/min
C) V_D/V_T of 0.45
D) MIP of -40 cm H₂O

Question 27

You determine that an acutely ill patient can generate an MIP of -18 cm H₂O. Based on this information, what might you conclude?

A) The patient has inadequate respiratory muscle strength.
B) The patient has inadequate alveolar ventilation.
C) The patient has an excessive work of breathing.
D) The patient has an unstable or irregular ventilatory drive.

Question 28

Because an elevated PaCO₂ increases ventilatory drive in normal subjects, the clinical presence of hypercapnia indicates which of the following?
1) Inability of the stimulus to get to the muscles
2) Weak or missing central nervous system response to the elevated PCO₂
3) Pulmonary muscle fatigue

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

Question 29

In patients suffering from acute respiratory acidosis, below what pH level are intubation and ventilatory support generally considered?

A) 7.2
B) 7.3
C) 7.1
D) 7.0

Question 30

A reversible impairment in the response of an overloaded muscle to neural stimulation best describes which of the following?

A) Central respiratory muscle fatigue
B) Transmission respiratory muscle fatigue
C) Contractile respiratory muscle fatigue
D) Chronic respiratory muscle fatigue

Question 31

Common bedside measures used to assess the adequacy of lung expansion include which of the following?
1) VC
2) Respiratory rate
3) V_T
4) V_D/V_T

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

Question 32

A need for some form of ventilatory support is usually indicated when an adult's rate of breathing rises above what level?

A) 35/min
B) 30/min
C) 25/min
D) 20/min

Question 33

What is the normal range for PaO₂/FiO₂?

A) 350 to 450
B) 250 to 350
C) 150 to 250
D) 75 to 150

Question 34

Ventilatory support may be indicated when the VC falls below what level?

A) 45 ml/kg
B) 65 ml/kg
C) 10 ml/kg
D) 30 ml/kg

Question 35

Inadequate respiratory muscle strength is likely when a patient's MVV is which of the following?

A) Less than 2 times the resting V_E
B) Greater than 3 times the resting V_E
C) Less than 200 L/min
D) Greater than 120 L/min

Question 36

Breathing 100% O₂, a patient has a PaO₂-PaO₂ of 60 mm Hg. Based on this information, what might you conclude?

A) The patient has severe hypoxemia.
B) The patient has an excessive work of breathing.
C) The patient has acceptable oxygenation.
D) The patient has inadequate ventilation.

Question 37

Which of the following indicate severely impaired oxygenation requiring high FiO₂s and positive end expiratory pressure?
1) PaO₂-PaO₂ greater than 350 mm Hg on 100% O₂
2) VC less than 10 ml/kg
3) PaO₂/FiO₂ less than 200
4) PaCO₂ greater than 45 mm Hg

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

Question 38

Mr. Adam is in the ICU on an FiO₂ of 100%. An arterial blood gas reveals the following information: pH of 7.18, PaCO₂ of 59 mm Hg, PaO₂ of 65 mm Hg, HCO₃ of 24 mEq/L What action would you recommend?

A) Provide ventilatory support.
B) Put patient on steroids.
C) Give patient chest PT.
D) Put patient on CPAP.

Question 39

Which of the following is the cardinal sign of increased work of breathing?

A) Hyperventilation
B) Retractions
C) Bradycardia
D) Tachypnea

Question 40

Your patient is hypoventilating. Which of the following would be likely findings?

A) A normal P(A-a)O₂ with a marked response to an increase in FiO₂
B) An increases P(A-a)O₂ with a marked response to an increase in FiO₂
C) A normal P(A-a)O₂ with no response to an increase in FiO₂
D) A increased P(A-a)O₂ with no response to an increase in FiO₂

Question 41

In intubated patients, what do sources of increased imposed work of breathing include?
1) Endotracheal tube
2) Ventilator circuit
3) Auto-PEEP

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

Question 42

Strategies to reduce auto-PEEP in mechanically ventilated patients with obstructive lung disease include which of the following?
1) Use high inspiratory flows (60 to 100 L/min).
2) Apply extrinsic PEEP.
3) Use low V_T values (8 to 10 ml/kg).
4) Use high respiratory rates (>25/min).

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

Question 43

Which of the following are causes of hypoxemia?
1) Ventilation/perfusion ( ) mismatch
2) Alveolar hypoventilation
3) Diffusion impairment
4) Increased inspired O₂

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

Question 44

Which of the following patients are at greatest risk for developing auto-PEEP during mechanical ventilation?

A) Those with acute lung injury
B) Those with COPD
C) Those with congestive heart failure
D) Those with bilateral pneumonia

Question 45

The respiratory therapist in the ICU is called to assess a patient with ARDS. The patient is SOB. The x-ray shows "white" chest radiograph and the PAO₂ is 60 mm Hg on an FiO₂ of 100%. Which of the following is indicated?

A) Shunting
B) Alveolar hyperventilation
C) Decreased CO₂
D) Perfusion impairment

Question 46

A patient who just suffered severe closed-head injury and has a high intracranial pressure (ICP) is about to be placed on ventilatory support. Which of the following strategies could help to lower the ICP?

A) Maintain a PaCO₂ from 25 to 30 mm Hg (deliberate hyperventilation).
B) Allow as much spontaneous breathing as possible (SIMV).
C) Maintain a high mean pressure using PEEP levels of 10 to 15 cm H₂O.
D) Maintain a PaCO₂ of 50 to 60 mm Hg (deliberate hypoventilation).

Question 47

A patient develops acute hypercapnic respiratory failure due to muscle fatigue. Which of the following modes of ventilatory support would you consider for this patient?
1) Assist-control ventilation with adequate backup
2) Continuous positive airway pressure
3) Intermittent mandatory ventilation with adequate backup rate
4) Bilevel pressure support by mask

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

Question 48

Which of the following modes of ventilatory support would you recommend for a severely hypoxemic patient with acute lung injury or acute respiratory distress syndrome (ARDS)?

A) Continuous positive airway pressure
B) High V_T volume-cycled ventilation
C) Pressure-controlled ventilation
D) Bilevel pressure support by mask

Question 49

Which of the following is the normal alveolar-to-arterial difference for a 56-year-old female in the emergency department?

A) 12 mm Hg
B) 14 mm Hg
C) 16 mm Hg
D) 18 mm Hg

Question 50

Which of the following modes of ventilatory support would you recommend for a hypoxemic patient with congestive heart failure?

A) Continuous positive airway pressure (CPAP)
B) Intermittent mandatory ventilation (IMV)
C) Inverse-ratio pressure-control ventilation (PCV)
D) High-level pressure support ventilation (PSV)

Question 51

What are some causes of dynamic hyperinflation?
1) Increased expiratory time
2) Increased airway resistance
3) Decreased expiratory flow rate

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

Question 52

When is respiratory muscle fatigue likely to occur?

A) When V_E exceeds 20% of the maximum voluntary ventilation (MVV)
B) When V_E exceeds 40% of the MVV
C) When V_E exceeds 60% of the MVV
D) When V_E exceeds 80% of the MVV