Which blood gas analyzer electrode uses a separate reference electrode?

(Answer to Q. 1)  ANS: B
The reference half-cell produces a constant potential, regardless of sample pH. The difference in potential between the two electrodes is proportional to the H+ concentration of the sample, which is displayed on a voltmeter calibrated in pH units.

(Answer to Q. 2)  ANS: C
In most units, the media used to calibrate the gas electrodes are precision mixtures of oxygen and carbon dioxide.

(Answer to Q. 3)  ANS: B
The primary parameters of pH, PCO2, and PO2 in a blood sample are measured with a blood gas analyzer.

(Answer to Q. 4)  ANS: B
The most common site for sampling is the heel, specifically the lateral aspect of the plantar sur-face. Before any puncture is done the site should be properly warmed to arterialize the skin and clean with an antiseptic solution to prevent infections.

(Answer to Q. 5)  ANS: D
To guide practitioners in providing quality care, the AARC has published Clinical Practice Guideline: Capillary Blood Gas Sampling for Neonatal and Pediatric Patients. Modified excerpts from the AARC guideline appear on p. 379.