Reliabilityof the Determinationof Whole-BloodOxygen Affinityby Means of Blood-Gas Analyzers and Multi-WavelengthOximeters

Determination of the oxygen affinity of human whole blood with the help of blood-gas analyzers and multi-wavelength oximeters is compared with an accurate method for recording hemoglobin oxygen dissociation curves (Gun Chem 1982;28:1 287-92). Pso (oxygen tension at half saturation; S02 = 50%) and Hill’s n (Iog [S02/(1- S02)]/log P02) were determined in blood of 24 healthy donors. Three slightly different procedures were used for determination of P50 on the basis of P02, pH, and S02 measured with each of four different blood-gas analyzer/oximeter combinations. These methods were not able to discriminate between high and low values for P50 within the normal reference interval, but never failed to detect the high oxygen affinity of blood stored for 12 days, reflected in low values of Pso. The methods thus proved suitable for detecting clinically signifi