The chest radiograph of a patient just placed on HFOV shows the ...

[wrbasek0]

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. mPaw
  b. Power
  c. Bias flow
  d. Amplitude

Question 2

PaCO2 can be reduced during HFOV by doing which of the following?
 
  a. Decreasing the amplitude
  b. Increasing the frequency
  c. Increasing the TI
  d. Decreasing the cuff leak

[kkenney]

Answer to Question 1

ANS: A
The mPaw directly affects the PaO2 by changing the lung volume. The position of the diaphragm on the chest radiograph correlates with lung expansion. Adequate lung expansion in an adult shows the ninth posterior rib above the level of the diaphragm in the midclavicular line. With this patient, the diaphragm is only at the seventh rib. Therefore, the mPaw needs to be increased to improve lung expansion.

Answer to Question 2

ANS: C
The PaCO2 can be reduced during HFOV by increasing the amplitude, decreasing the frequency, increasing the TI to 50, and increasing the cuff leak.