During the course of several patient-ventilator system checks a ...

[Yolanda]

During the course of several patient-ventilator system checks a respiratory therapist notices that the patient's peak inspiratory pressure (PIP) is rising, while the plateau pressure (Pplateau) has re-mained the same.
 
  This most likely indicates which of the following?
  a. Decrease in dynamic compliance
  b. Increase in airway resistance
  c. Decrease in static compliance
  d. Increase in elastic recoil of alveolar walls

Question 2

Calculate the volume delivered to the patient when the tubing compliance (CT) is 2.5 mL/cm H2O, the tidal volume (VT) at the exhalation port is 550 mL, and the peak inspiratory pressure (PIP) is 28 cm H2O.
 
  a. 70 mL
  b. 330 mL
  c. 480 mL
  d. 620 mL

[amy.lauersdorf90]

Answer to Question 1

ANS: B
The difference between the peak inspiratory pressure (PIP) and plateau pressure (Pplateau) readings (PIP  Pplateau) is the transairway pressure (PTA). PTA is the amount of pressure required to over-come airway resistance (Raw) (Raw = PTA/Flow). Notice that PTA includes the resistance of the en-dotracheal tube (ET). A higher than expected difference between PIP and Pplateau suggests an in-creased Raw.

Answer to Question 2

ANS: C
Volume lost = PIP  CT and Delivered VT = Measured VT  Volume lost

[Yolanda]

Excellent

[mohan]

TYSM