During pressure-targeted ventilation with volume guaranteed for ...

[maegan_martin]

During pressure-targeted ventilation with volume guaranteed for every breath, the set volume is not met. Which of the following phase variables would cycle that breath?
 
  a. Time c. Volume
  b. Flow d. Pressure

Question 2

What is the expiratory time when the tidal volume is 700 mL, the flow rate is 50 L/min, and the inspiratory time-to-expiratory time ratio is 1:3?
 
  a. 0.42 second c. 2.52 seconds
  b. 0.70 second d. 4.67 seconds

[Toya9913]

Answer to Question 1

ANS: C
If the volume is not delivered by the time flow decreases to its set value during pressure-targeted ventilation with volume guaranteed for every breath, the flow continues at the amount set on the flow control until the set tidal volume is delivered. Inspiration becomes volume cycled.

Answer to Question 2

ANS: C
Inspiratory time = Tidal volume (in liters)  Flow rate (in liters/second) = 0.7 L  0.83 L/s = 0.84 s. Expiratory time = 3  Inspiratory time = 3  0.84 = 2.52 s.