You can find the answers to these questions in the TMC Test Bank.

1. To ensure the accuracy of a specialty gas analyzer (e.g., CO, He, NO) prior to making a measurement you should:

A. slope the analyzer to a calibrated high gas value
B. leave device on for 5 minute to confirm minimal drift
C. balance the analyzer using a ‘zero’ reference gas
D. perform a two-point calibration (‘zero’ + full scale)

2. Which of the following blood gas sampling errors would tend to result in a falsely high pH?

A. use of a glass syringe
B. ongoing blood metabolism
C. air bubbles in the sample
D. severe erythrocytosis

3. To validate the accuracy of a new blood gas analyzer that will replace an existing in-use device, you would:

A. perform duplicate analysis of a sample on both analyzers
B. review the statistical quality control results of the existing analyzer
C. perform preventative maintenance on the new analyzer
D. complete the electronic self-testing procedure on the new analyzer

4. The best way to avoid arterial blood gas analysis errors associated with blood metabolism is to:

A. analyze the sample immediately
B. place the sample in an ice slush
C. uncap the syringe to get rid of any air
D. use dry (lithium) heparin

5. During an extended self-test of a ventilator, you receive multiple failure warnings, but are allowed to bypass them and complete the test. Which of the following would be your best course of action?

A. document the test results and limit the ventilator use to ‘passed’ functions only
B. take the ventilator out of service and replace it with a fully functional device
C. document the test results and make the ventilator available for full patient use
D. enter the ventilator’s setup program and change the self-test options

6. To standardize a transcutaneous blood gas monitor’s measurements you should:

A. run a two-point calibration using precision gas mixtures
B. expose the sensor to air to confirm ambient PO2 and PCO2
C. compare its readings to a concurrent blood gas sample
D. expose the sensor to blood gas analyzer liquid control media

7. Which of the following blood gas sampling errors would tend to result in a falsely low PCO2?

A. collection in plastic syringe
B. air contamination of sample
C. admixture with venous blood
D. delay in sample analysis

8. You review the following quality control graph (Levy-Jennings chart) for one of a blood gas analyzer’s measurements, with each dot representing a control run and SD = standard deviation. Based on review of this chart, which of the following conclusions can you draw?

A. a shift may be coming
B. a trend has developed
C. the device is in control
D. there is excessive variability

9. Which of the following blood gas sampling errors would tend to result in a falsely low pH?

A. excess liquid heparin
B. use of a glass syringe
C. venous admixture
D. air bubbles in sample

10. A normal 5-foot 3-inch tall RT staff member serves as a biologic control for the PFT lab. Her established FVC is 3.80 L with a SD of ±0.14 L. During quality control testing of a spirometer, she produces the following FVC results:

FVC #1 = 3.74 L
FVC #2 = 3.89 L
FVC #3 = 3.70 L

You should conclude that the

A. the subject’s FVC maneuvers reveal inadequate effort
B. the results are repeatable but not sufficiently accurate
C. the subject’s FVC maneuvers are not sufficiently repeatable
D. the spirometer is performing within acceptable limits

11. To calibrate a portable bedside spirometer you need which of the following equipment?

A. a U-tube water column manometer
B. a mechanical (vane-type) respirometer
C. a large volume (3 L) calibration syringe
D. a precision calibrated flowmeter

12. You review the following quality control graph (Levy-Jennings chart) for one of a blood gas analyzer’s measurements, with each dot representing a control run and SD = standard deviation. Control run #14 (identified by arrow) indicates which of the following?

A. failure of an analyzer component
B. random error/chance occurrence
C. incorrect calibrating gas(es)
D. contaminated buffer solution(s)

13. During a ventilator test, you determine that the delivered volume is substantially less than the set volume. To determine if the ventilator volume setting is out of calibration, you would:

A. measure the volume delivered at the ventilator outlet using a calibrated volumeter
B. perform a manual circuit leak test using a low volume and inspiratory pause
C. compare a variety of inspiratory time settings against a digital stop watch
D. measure the volume delivered at the patient connector using a calibrated volumeter

14. To verify the operation of a pulse oximeter, you would

A. Expose the oximeter sensor to a calibrated high and low O2 gas source
B. Measure the SpO2 on two patients with different ABG saturation values
C. Confirm measurements with high/low HbO2 saturation control media
D. Confirm an SpO2 ≥ 97% and an accurate pulse reading on a normal person

15. The following figure represents the PO2 calibration curves (initial vs. desired) for a manually calibrated blood gas analyzer. To eliminate the difference labeled ‘A’ between the pre-calibration and desired response, you would:

A. change the calibration controls to match the actual (desired) input
B. adjust the offset (balance) so that the low output equals the low input
C. check and replace the PO2 electrode’s membrane
D. adjust the gain (slope) so that the high output equal the high input

16. The following figure is a statistical quality control plot for measurements made by a blood gas analyzer. What type of error is represented by last 10 control runs (right side of plot)?

A. instrument bias
B. computation error
C. instrument imprecision
D. random error

17. Which of the following can cause a hemoximeter’s HbO2 reading to be falsely low?

A. dirty analysis chamber
B. high fetal Hb levels
C. elevated bilirubin levels
D. sickle-cell anemia

18. Which of the following can cause a hemoximeter’s HbO2 reading to be falsely high?

A. incomplete hemolysis
B. presence of vascular dyes
C. sickle-cell anemia
D. elevated bilirubin levels

19. When performing a leak test on a volume ventilator, you should

A. open the breathing circuit to the atmosphere
B. set the flow control at maximum
C. set the high pressure limit at maximum
D. set the tidal volume at 2 L

20. Upon inspection of a FVC graph obtained on an adult patient using a portable spirometer, you observe an ‘S’ shaped curve. This most likely indicates which of the following?

A. coughing during the maneuver
B. poor effort at the start of the breath
C. breathing during the maneuver
D. prematurely stopping exhalation

21. How often should you conduct blood gas or hemoximetry calibration verification using control media?

A. at least one control should be analyzed every 8 hours
B. at least one control should be analyzed every hour
C. at least three control should be analyzed every 8 hours
D. at least one control should be analyzed every 24 hours

22. The following figure is a statistical quality control plot for measurements made by a blood gas analyzer. Control run #14 (identified by the arrow) should prompt which of the following actions?

A. send the sample out for proficiency testing
B. rerun the sample on a different analyzer
C. repair or replace the applicable components
D. dispose of all control media from the same batch

23. To conduct a manual leak test on a ventilator circuit, you would:

A. trigger a small volume/inspiratory pause breath into an occluded circuit
B. trigger a large volume/high flow breath into a test lung
C. trigger a small volume/inspiratory pause breath through an open circuit
D. fill the circuit with water and observe if there is any leakage

24. The low FIO2 alarm on a ventilator with a built-in galvanic fuel cell O2 analyzer keeps activating. After you check and confirm source gas connections and the delivered FIO2 (using a separate O2 analyzer), your attempt to calibrate the built-in analyzer fails. Which of the following should you do NEXT?

A. change the battery
B. recalibrate the analyzer
C. replace the fuel cell
D. re-membrane the electrode

25. After a patient performs a forced vital capacity (FVC) maneuver, you observe the following volume vs. time plot on the screen of a portable spirometer. What validity error does this plot indicate?

A. too slow a start to forced exhalation
B. coughing during the maneuver
C. breathing during the maneuver
D. premature end to expiration

26. You are checking an ICU ventilator and observe that the exhaled volume is significantly less than the set volume. To determine if this problem is due to an inaccurate ventilator volume control, you should measure the volume at the:

A. machine outlet
B. patient connector
C. exhalation valve
D. water collection bottle

27. Following prescribed daily quality control procedures in your blood gas lab, you run a control solution through the blood gas analyzer. You note that two successively PCO2 readings fall outside the acceptable range. Which of the following actions is appropriate at this time?

A. report results after compensating for the deviation
B. replace the PCO2 electrode and recalibrate the analyzer
C. analyze another control solution for comparison
D. perform a two-point calibration and rerun the control

28. You suspect that an arterial blood gas sample obtained on an ICU patient is venous blood. Which of the following would be the best way to confirm this suspicion?

A. compute the alveolar-arterial O2 gradient or P(A-a)O2
B. cross-check the results against the patient’s SpO2
C. compute the patient’s P/F ratio (PaO2/FIO2)
D. interview the nurse who obtained the sample

29. While checking a galvanic fuel cell oxygen analyzer, you determine that the device fails to read 100% when exposed to pure oxygen. Which of the following actions would be correct?

A. check the silica crystals
B. change the analyzer’s fuel cell
C. replace the analyzer’s batteries
D. check the barometric pressure

You can find the answers to these questions in the TMC Test Bank.