You are asked to calibrate an O2 analyzer. Which of the following ...

[Haya94]

You are asked to calibrate an O2 analyzer. Which of the following gases would you use for this procedure? 1. 100 oxygen 2. 50 oxygen 3. 21 oxygen (room air)
 
  a. 1 and 2 only
  b. 1 and 3 only
  c. 2 and 3 only
  d. 1, 2, and 3

Question 2

When performing an Allen test on the left hand of a patient, you notice that the palm, fingers, and thumb remain blanched for more than 15 sec after pressure on the ulnar artery is released. What should you do?
 
  a. Use the brachial site for sampling.
  b. Sample from the contralateral radial artery.
  c. Use the femoral site for sampling.
  d. Perform the Allen test on the right hand.

[todom5090]

Answer to Question 1

ANS: B
To obtain accurate results with an O2 analyzer, the clinician first must calibrate it according to manufacturer's recommendations. Although procedures differ according to the manufacturer, the basic steps are similar, requiring exposure of the sensor to two gases with different O2 concentra-tions, usually 100 O2 and room air (21 O2). In one common procedure, the sensor is first ex-posed to 100 O2. If the analyzer fails to read 100, the device's calibration, or balance control, must be adjusted until it reads 100. Then, the clinician exposes the sensor to room air and con-firms a second reading of 21 (2). The clinician should use the analyzer to measure a pa-tient's FiO2 only after confirming both readings.

Answer to Question 2

ANS: D
Box 19-2 outlines the basic procedure for radial artery puncture of adults.