Deck 13: Improving Oxygenation and Management of ARDS

Question 1

The level of applied PEEP should be set at what point on the pressure-volume curve?

A) At the upper inflection point of the inflation curve.
B) Above the lower inflection point of the deflation curve.
C) At the peak inspiration point of the inflation curve.
D) Above the upper inflection point of the deflation curve.

Answer 1

D
The level of applied PEEP should be set 3-4 cm H₂O above the upper inflection point of the deflation limb of the P-V curve to help maintain an open lung.

Question 2

Calculate the pulmonary shunt fraction for a patient with the following data: Pb = 760 mm Hg; Hb = 10 g/dL; respiratory quotient = 0.8; FɪO₂ = 0.6; PₐO₂ = 100 mm Hg; SₐO₂ = 93%; PₐCO₂ = 45 mm Hg; = 36 mm Hg; = 70%.

A) 13%
B) 26%
C) 30%
D) 41%

Answer 2

B

Question 3

An absolute contraindication to PEEP is which of the following?

A) Emphysema
B) Bronchopleural fistula
C) Untreated tension pneumothorax
D) Elevated intracranial pressures

Answer 3

C
An absolute contraindication to PEEP is a tension pneumothorax.PEEP must be used with care in patients with bronchopleural fistulas and elevated intracranial pressures.PEEP also must be used with care in patients with emphysema,because it may increase hyperinflation,which can lead to compression of adjacent capillaries.

Question 4

A patient is being ventilated with a PEEP of 10 cm H₂O and an FɪO₂ of 0.4.The arterial blood gas results show that the patient remains hypoxemic,and the respiratory therapist increases the PEEP to 18 cm H₂O,maintaining the FɪO₂ at 0.4.The patient's static compliance changes from 28 to 22 mL/cm H₂O just after this change.The respiratory therapist should do which of the following?

A) Decrease PEEP to 10 cm H₂O and increase the FɪO₂ to 0.6.
B) Decrease PEEP to 15 cm H₂O and measure static compliance.
C) Keep PEEP at 18 cm H₂O and increase the FɪO₂ to 0.6.
D) Increase PEEP to 20 cm H₂O and measure static compliance.

Question 5

Which of the following is the most appropriate PEEP level for the patient whose information is in the table below?

A) 10 cm H₂O
B) 12 cm H₂O
C) 15 cm H₂O
D) 18 cm H₂O

Question 6

During mechanical ventilation of a patient with CHF,the PₐO₂ = 38 mm Hg and the FɪO₂ = 0.6.If the desired PₐO₂ is 60 mm Hg,the FɪO₂ needs to be changed to which of the following?

A) 0.65
B) 0.75
C) 0.85
D) 0.95

Question 7

What is the optimal PEEP level given the following information?

A) 8 cm H₂O
B) 10 cm H₂O
C) 12 cm H₂O
D) 15 cm H₂O

Question 8

Regardless of the procedure used to establish an appropriate PEEP level,ventilating pressures should not be allowed to exceed which of the following?

A) Upper inflation point on the inspiratory limb (UIPi)
B) 2-3 cm H₂O above the UIPi
C) 30 cm H₂O
D) Lower inflection point on the inspiratory limb

Question 9

Calculate the pulmonary shunt fraction for a patient with the following data: CᴀO₂ = 17 vol%; CₐO₂ = 16.5 vol%; = 11 vol%.

A) 8%
B) 15%
C) 30%
D) 37%

Question 10

What is the Pflₑₓ on the following pressure-volume loop?

A) 10 cm H₂O
B) 15 cm H₂O
C) 19 cm H₂O
D) 23 cm H₂O

Question 11

The level of PEEP that is most appropriate for a patient with the information shown below is which of the following?

A) 8 cm H₂O
B) 10 cm H₂O
C) 12 cm H₂O
D) 15 cm H₂O

Question 12

Assessing the outcome of PEEP at levels set above 15-20 cm H₂O is best done using which of the following?

A) Static compliance measurements
B) Pressure-volume loop graphics
C) Pulmonary artery occlusion pressure
D) Central venous pressure measurements

Question 13

During mechanical ventilation of a patient with COPD,the PₐO₂ = 58 mm Hg and the FɪO₂ = 0.5.If the desired PₐO₂ is 65 mm Hg,the FɪO₂ needs to be changed to which of the following?

A) 0.44
B) 0.56
C) 0.65
D) 0.74

Question 14

PEEP therapy is indicated for patients with which of the following?

A) PₐCO₂ of 95 mm Hg while receiving an FɪO₂ of 0.3
B) PₐCO₂ of 100 mm Hg while receiving an FɪO₂ of 0.8
C) Returned Vᴛ of 600 mL with a Pₚₗₐₜₑₐᵤ of 12 cm H₂O
D) Returned Vᴛ of 800 mL with a Pₚₗₐₜₑₐᵤ of 15 cm H₂O

Question 15

Which of the following patients may benefit from PEEP?

A) COPD
B) Asthma
C) ARDS
D) Cystic fibrosis

Question 16

What is the optimal PEEP level given the following information?

A) 8 cm H₂O
B) 10 cm H₂O
C) 12 cm H₂O
D) 15 cm H₂O

Question 17

Thirty minutes after intubation and initiation of mechanical ventilation,a patient's PₐO₂ = 55 mm Hg and the FɪO₂ = 0.5.To what should the FɪO₂ be set to obtain a PₐO₂ of 80 mm Hg?

A) 0.65
B) 0.75
C) 0.85
D) 0.95

Question 18

Calculate the pulmonary shunt fraction using the following data: Pb = 757 mm Hg; hemoglobin (Hb)= 11 g/dL; FɪO₂ = 0.5; PₐO₂ = 86 mm Hg; PₐCO₂ = 40 mm Hg; SₐO₂ = 91%; = 40 mm Hg; = 71%; respiratory exchange quotient (R)= 0.8.

A) 19%
B) 23%
C) 26%
D) 32%

Question 19

How long after PEEP is increased should all ventilatory and available hemodynamic parameters be measured and calculated?

A) 5 minutes
B) 15 minutes
C) 25 minutes
D) 40 minutes

Question 20

A patient with ARDS has the slow pressure-volume loop shown below.Based on this loop,at what level should PEEP be set?

A) 10 cm H₂O
B) 12 cm H₂O
C) 18 cm H₂O
D) 22 cm H₂O

Question 21

During a patient case study,increasing increments of PEEP showed no significant effects until 15 cm H₂O was used,at which time the PₐO₂ improved markedly.This represents the point at which _______________.

A) cardiac output decreased
B) airway resistance decreased
C) hemoglobin saturation improved
D) alveolar recruitment probably occurred

Question 22

The highest pressure attained during the slow-flow (quasi-static)technique should be ______ cm H₂O.

A) 25
B) 35
C) 45
D) 55

Question 23

"Loose atelectasis," or compression atelectasis,is most often associated with _____________.

A) ALI
B) ARDS
C) anesthesia
D) pulmonary fibrosis

Question 24

The "sigmoid" shape of the static pressure-volume lung recruitment maneuver indicates which of the following?

A) All parts of the lungs open with the same pressure.
B) Independent portions of the lungs open with the same pressure.
C) Dependent portions of the lungs open with different pressures.
D) Lung units open at different times with different pressures.

Question 25

An invasively ventilated patient with ARDS is on PC-CMV,PIP = 30 cm H₂O,PEEP = 12 cm H₂O,FɪO₂ = 1.0.The patient's returned Vᴛ is 320 mL.The ABG results on these settings are: pH 7.3,PₐCO₂ 53 mm Hg,PₐO₂ 62 mm Hg.The patient is placed in the prone position,and after 1 hour,ABG results show: pH 7.38,PₐCO₂ 46 mm Hg,PₐO₂ 83 mm Hg.The respiratory therapist should do which of the following?

A) Keep the patient in the prone position.
B) Place the patient in the supine position.
C) Keep the patient in the prone position and decrease the FɪO₂.
D) Place the patient in the supine position and decrease PEEP.

Question 26

The patient with which of the following assessment findings meets the criteria for beginning weaning from PEEP?

A) PₐCO₂ = 85 mm Hg; FɪO₂ = 0.6; Cₛ = 20 mL/cm H₂O; PEEP = 12 cm H₂O
B) PₐCO₂ = 100 mm Hg; FɪO₂ = 0.9; Cₛ = 22 mL/cm H₂O; PEEP = 10 cm H₂O
C) PₐCO₂ = 150 mm Hg; FɪO₂ = 0.7; Cₛ = 25 mL/cm H₂O; PEEP = 12 cm H₂O
D) PₐCO₂ = 95 mm Hg; FɪO₂ = 0.3; Cₛ = 30 mL/cm H₂O; PEEP = 15 cm H₂O

Question 27

A recruitment maneuver (RM)is being performed on a patient receiving mechanical ventilation with PCV.During the maneuver the mode remains in PCV,rate = 10/min,I:E = 1:2,and PIP = 35 cm H₂O.The following information is documented during the RM:

After the RM,the lungs are reinflated.At what level should the PEEP be set for this patient?

A) 12 cm H₂O
B) 17 cm H₂O
C) 22 cm H₂O
D) 27 cm H₂O

Question 28

In which ventilator mode should a patient receiving a sustained inflation technique be placed?

A) VC-CMV
B) APRV
C) PC-IMV
D) CPAP/spontaneous

Question 29

A patient with extensive infiltrates throughout the right lung should be placed in which of the following positions to improve oxygenation?

A) Left lung down laterally
B) Right lung down laterally
C) Left lung down with right lung 45 degrees from supine
D) Right lung down with left lung 45 degrees from supine

Question 30

Despite the risk,it is still important to use PEEP,because it can prevent alveolar collapse during exhalation and reopening,even when a low Vᴛ is used.It now is theorized that it is important to use the pressure-volume loop to set PEEP _____________________.

A) at the upper inflection point detected during inflation of the lung
B) above the upper inflection point detected during deflation of the lung
C) at the lower inflection point detected during inflation of the lung
D) at the peak inspiration point detected during inflation of the lung

Question 31

The point on a static pressure-volume curve (SPV)where the alveoli begin to open is referred to as which of the following?

A) Lower inflection point on the inflation limb
B) Upper inflection point on the inflation limb
C) Upper inflection point on the deflation limb
D) Lower inflection point on the deflation limb

Question 32

To perform a slow-flow (quasi-static)technique for determining the appropriate PEEP level,the most appropriate ventilator flow setting is which of the following?

A) 2 L/min
B) 6 L/min
C) 10 L/min
D) 14 L/min