Use of Carbon Dioxide- and Oxygen-Tonometered Phosphate— Bicarbonate—Chloride—Glycerol—Water Mixtures for Calibration and Control of pH, pco2 and pO2 Electrode Systems

[摘要] Calibration of pH, p co2, and p o2 electrode systems of modern blood—gas analyzers, designed with one sample cuvet for measurement, is mostly performed separately with buffer solutions and gas mixtures. We describe the development of solutions of known pH, p co2 and p o2 for doing such calibrations simultaneously, containing phosphate, bicarbonate, and chloride in glycerol—water mixtures as solvent. A method is suggested for computing the relation between pH and log p CO2 of these solutions in equilibrium with carbon dioxide gas. It is demonstrated that a solution of phosphate (Na2HPO4, KH2PO4, each 25.mmol/liter), bicarbonate (NaHCO3, 30 mmol/ liter), and chloride (NaCI, 30 mmol/ liter) in glycerol-water mixture (3/7 by vol) and equilibrated with CO2 in air (4 vol/100 vol) and CO2 in nitrogen (8 vol/100 vol), respectively, makes possible accurate and simultaneous calibration of the pH, p co2, p o2 electrodes of a Corning Model 165 blood—gas analyzer. Similar solutions may also be used for quality—control of blood—gas measurement.

[学科分类] 过敏症与临床免疫学