A well-fitted nonrebreathing mask, adjusted so that the patient's ...

[future617RT]

A well-fitted nonrebreathing mask, adjusted so that the patient's inhalation does not deflate the bag (flows approximately 10 L/min), should provide inspired O2 concentrations in what range?
 
  a. 55 to 70
  b. 45 to 60
  c. 75 to 90
  d. 70 to 85

Question 2

A physician orders 2 L/min O2 through a simple mask to a 33-year-old postoperative woman with moderate hypoxemia breathing room air (PaO2 = 52 mm Hg). What would be the correct action at this time?
 
  a. Carry out the physician's prescription ex-actly as written.
  b. Recommend that the mask be changed to a cannula at 2 L/min.
  c. Recommend a flow of at least 5 L/min to washout carbon dioxide (CO2).
  d. Do not apply the O2 until the medical di-rector has been contacted.

[Ashley I]

Answer to Question 1

ANS: A
As indicated in Table 41-3, however, modern disposable nonrebreathing masks normally do not provide much more than approximately 70 O2.

Answer to Question 2

ANS: C
At a flow less than 5 L/min, the mask volume acts as dead space and causes CO2 rebreathing.

[future617RT]

Thanks for the timely response, appreciate it

[gcook]

Great answer, keep it coming