Quality specifications for pH and blood gases

This presentation is built upon experience with use of blood gas results in clinical work during 25 years, experience from the external quality control of 120 blood-gas-analyzers participating in the Norwegian Control Survey 1984-1991, and at last 3 different pH/blood gas inter-analyzer comparisons in Oslo and Bergen in 1980, 1990 and 1992. It is discussed the pure biological variations of the three parameters pH, pCO2 and pO2 as well as the variations in results caused by preanalytical and analytical factors. My proposal for goal of quality for determinations of blood gases (the pure analytical variations, given as EA, Error Allowable) are; pH: 0.02 units on all levels as SD, pCO2: 1-2% (CV) depending on level and the clinical situation. pO2: 2-4% (CV) depending on the level and clinical situation.