CAP blood gas survey--1981 and 1982.

The results of the 1982 CAP Blood Gas Survey, in which fluorocarbon-based emulsion specimens were used, are compared to the 1981 results, in which aqueous specimens were used. Interinstrument differences exist with all three analytes, pH PCO2, and PO2. There was little difference in interlaboratory precision of pH and PCO2 determinations in the two surveys. The coefficients of variation for PO2 determination were lower in 1982 than in 1981. This is attributed to the oxygen buffering capacity of fluorocarbon. Without a reference method for measuring blood pH, PCO2, and PO2, precision and interinstrument differences can be measured, but accuracy cannot.