The acceptable lower limit of PaO2 for a mechanically ventilated ...

[vicky]

The acceptable lower limit of PaO2 for a mechanically ventilated patient with ARDS is which of the following?
 
  a. 50 mm Hg
  b. 60 mm Hg
  c. 70 mm Hg
  d. 80 mm Hg

Question 2

What is the minimum range of time constants necessary for the lungs to empty 98 of the in-spired volume?
 
  a. 1-2
  b. 2-3
  c. 3-4
  d. 4-5

[jjorrostieta]

Answer to Question 1

ANS: B
The lower limits of permissive hypoxemia remain controversial. However, most clinicians agree that a target of PaO2 = 60 mm Hg and SpO2 = 90 are acceptable lower limits.

Answer to Question 2

ANS: C
An expiratory time of at least 3-4 time constants is needed for the lungs to empty 98 of the in-spired volume.