Deck 23: Special Techniques in Ventilatory Support

Question 1

An adult patient with ARDS is being ventilated with VC-CMV.The settings are: f = 14 breaths/min;V_T = 375 mL;PEEP = 16 cm H₂O;and F_IO₂ = 0.8.The patient's ABG values are: pH = 7.40;PaCO₂ = 56 mm Hg;PaO₂ = 48 mm Hg;and SaO₂ = 83%;the mean airway pressure is 18 cm H₂O.The patient's physician decides on a trial of HFOV.What initial ventilator settings should be used?

A) Bias flow = 30 L/min;mP_aw = 23 cm H₂O;set power to obtain $\Delta$ P = 76 cm H₂O;f = 6 Hz;T_I = 33%;F_IO₂ = 1.0
B) Bias flow = 35 L/min;mP_aw = 76 cm H₂O;set power to obtain $\Delta$ P = 33 cm H₂O;f = 10 Hz;T_I = 50%;F_IO₂ = 1.0
C) Bias flow = 20 L/min;mP_aw = 18 cm H₂O;set power to obtain $\Delta$ P = 76 cm H₂O;f = 8 Hz;T_I = 33%;F_IO₂ = 1.0
D) Bias flow = 30 L/min;mP_aw = 30 cm H₂O;set power to obtain $\Delta$ P = 56 cm H₂O;f = 6 Hz;T_I = 50%;F_IO₂ = 1.0

Answer 1

Bias flow = 30 L/min;mP_aw = 23 cm H₂O;set power to obtain $\Delta$ P = 76 cm H₂O;f = 6 Hz;T_I = 33%;F_IO₂ = 1.0

Question 2

The HFOV setting that directly affects PaO₂ is the _____________.

A) Power
B) mP_aw
C) Amplitude
D) Bias flow

Answer 2

mP_aw

Question 3

The chest radiograph of a patient just placed on HFOV shows the diaphragm at the level of the seventh rib.Which of the following parameters should be adjusted?

A) mP_aw
B) Power
C) Bias flow
D) Amplitude

Answer 3

mP_aw

Question 4

In the APRV mode,which of the following is considered baseline?

A) P_low
B) P_high
C) T_low
D) T_high

Question 5

Which of the following ventilators is unaffected by the use of heliox,whatever the F_IO₂?

A) Dräger E-4
B) Servo 300
C) Hamilton Galileo
D) Puritan Bennett 840

Question 6

When T_high is set at 5.5 seconds,and the T_low is set at 0.5 seconds;what is the set ventilator rate?

A) 8
B) 10
C) 14
D) 16

Question 7

The advantage of APRV over VC-CMV or PC-CMV is which of the following?

A) It enhances CO₂ elimination.
B) Volume delivery is consistent.
C) Independent lung regions are better ventilated.
D) It reduces the risk of ventilator-induced lung injury.

Question 8

The variable that allows for an unimpeded expiratory gas flow is which of the following?

A) T_low
B) T_high
C) P_low
D) P_high

Question 9

What is the maximum pressure setting for P_high?

A) 25 cm H₂O
B) 30 cm H₂O
C) 35 cm H₂O
D) 40 cm H₂O

Question 10

Weaning from APRV includes which of the following?

A) Increasing the P_high and decreasing the T_high
B) Decreasing the P_high and increasing the T_high
C) Increasing the P_low and decreasing the T_low
D) Decreasing the P_low and increasing the T_low

Question 11

An 80% He:20% O₂ mixture is being delivered to an asthmatic patient by a nonrebreathing mask through an oxygen flow meter set at 8 L/min.What is the actual flow delivered to the patient?

A) 10 L/min
B) 12 L/min
C) 14 L/min
D) 18 L/min

Question 12

A patient being ventilated with APRV has the following settings: P_high = 24 cm H₂O;T_high = 5 sec;P_low = 4 cm H₂O;T_low = 1 sec,F_IO₂ = 0.3.The patient's spontaneous respiratory rate is 10 breaths/min.The current arterial blood gas values are: PaO₂ = 91 mm Hg;PaCO₂ = 62 mm Hg.What should the respiratory therapist recommend for this patient?

A) Increase the P_low to 5.5 cm H₂O.
B) Decrease the T_low to 0.5 sec.
C) Increase the P_high to 40 cm H₂O.
D) Decrease the P_low to 0 cm H₂O.

Question 13

Compared with pressure-controlled inverse ratio ventilation,APRV does which of the following?

A) Decreases the cardiac index
B) Reduces the need for sedation
C) Increases the peak airway pressure
D) Increases the central venous pressure

Question 14

The PaCO₂ can be reduced during HFOV by doing which of the following?

A) Decreasing the amplitude
B) Increasing the frequency
C) Increasing the T_I%
D) Decreasing the cuff leak

Question 15

Observation of chest wall movement,or the "chest wiggle factor," is used to assess the appropriateness of the ___________.

A) mP_aw
B) frequency
C) bias flow
D) power setting

Question 16

Which of the following is an alternative method of respiratory support for patients with ALI/ARDS?

A) IPV
B) ILV
C) HFOV
D) Heliox therapy

Question 17

Which variable in APRV is responsible for the removal of CO₂ from the body?

A) T_low
B) T_high
C) P_low
D) P_high

Question 18

The most common concentration of heliox is ________________.

A) 50% helium:50% oxygen
B) 60% helium:40% oxygen
C) 70% helium:30% oxygen
D) 80% helium:20% oxygen

Question 19

The key property of helium that makes it useful as a therapeutic gas is its ____________.

A) low cost
B) low density
C) low solubility
D) abundance in nature

Question 20

A patient with ALI is being ventilated using APRV with the following settings: P_high = 30 cm H₂O;P_low = 2 cm H₂O;T_high = 6 sec;T_low = 0.8 sec;F_IO₂ = 0.4.The patient's spontaneous rate is 12 breaths/min.The current ABG values are: PaO₂ = 61 mm Hg;PaCO₂ = 43 mm Hg.What change should the respiratory therapist recommend for this patient?

A) Decrease the P_high to 25 mm Hg.
B) Increase the T_high to 8 seconds.
C) Decrease the T_low to 0.5 seconds.
D) Increase the P_low to 5 cm H₂O.