Which of the following are true statements regarding the volume ...

[tiara099]

Which of the following are true statements regarding the volume of tissue nitrogen excreted dur-ing the N2 washout test for measuring functional residual capacity (FRC)?
 
  1. It is not a factor.
  2. It varies with the length of the test.
  3. It varies with the weight of the patient.
  4. It cannot be correct.
  a. 1 only
  b. 2 and 3 only
  c. 2, 3, and 4 only
  d. 4 only

Question 2

To what should all spirometric values obtained under ambient conditions be converted?
 
  a. Ambient temperature and pressure, satu-rated (ATPS)
  b. Standard temperature and pressure, dry (STPD)
  c. Body temperature, ambient pressure, sat-urated (BTPS)
  d. Ambient temperature and pressure, dry (ATPD)

[ryhom]

Answer to Question 1

ANS: B
The volume of tissue nitrogen excreted (Vtis in milliliters) is directly related to the duration (t in minutes) of the test and weight (W in kilograms) of the patient. A correction for this extra nitro-gen should be made according to the following formula:
Vtis (ml) = (0.1209  0.0665)  (W/70). Vtis (ml) is subtracted from the BTPS-corrected lung volume. The residual volume is the difference between the expiratory reserve volume and the FRC.

Answer to Question 2

ANS: C
All lung volumes and capacities must be reported under BTPS conditions.

[tiara099]

TYSM

[samiel-sayed]

Excellent