A flexible and versatile program for blood-gas quality control

A quality control program which related quality control data to maintenance procedures has been developed. Whole blood tonometered at three levels of pCO2 and pO2 is used as the quality control material. A key feature of the program is that control values are independent of barometric pressure. The recording format consolidates results at all levels for each constituent, and permits direct comparison with maintenance procedures or electrode changes. The tonometry system consists of a precision gas mixer, Corning Model 192, and a two-channel syringe tonometer, Corning Model 184. This system provides several advantages for quality control, including: (1) use of Levy-Jenning charts with constant "mean values" for tonometered blood; (2) evaluation of electrode linearity over a wide range of partial pressures; and (3) multiple values for each parameter tested. Recovery of theoretical values over a broad range of partial pressure allows more accurate assessment of proportional response for assignment of pO2 "correction factors." Differences between instruments may also be investigated in closer detail.