Ralston A C, Webb R K, Runciman W B
Department of Anaesthesia and Intensive Care, Royal Adelaide Hospital, South Australia.
Anaesthesia. 1991 Mar;46(3):202-6. doi: 10.1111/j.1365-2044.1991.tb09410.x.
There is no absolute reference for oxygen saturation, although multiwavelength in vitro oximeters are accepted as the 'gold standard'. Regardless of whether fractional or functional saturation is used by manufacturers to calibrate their oximeters, evaluation against fractional saturation is recommended since this is the clinically relevant variable. The use of standard notation and comparisons based on bias and precision is recommended. The accuracy of pulse oximetry is intrinsically limited by the use of only two wavelengths, and is dependent on the initial calibration population. The empirical algorithms used to convert the signal to its 'readout value' and the quality control of hardware may both be important sources of variability between oximeters. Change in blood temperature may introduce errors in pulse oximeter and in vitro oximeter saturation readings, but these will be clinically insignificant. Changes in blood pH should not decrease pulse oximetry accuracy.
尽管多波长体外血氧计被公认为“金标准”，但血氧饱和度并没有绝对的参考标准。无论制造商使用分数饱和度还是功能饱和度来校准其血氧计，建议根据分数饱和度进行评估，因为这是临床相关变量。建议使用标准符号并基于偏差和精密度进行比较。脉搏血氧测定法的准确性本质上受到仅使用两个波长的限制，并且取决于初始校准人群。用于将信号转换为其“读数”值的经验算法以及硬件的质量控制都可能是血氧计之间变异性的重要来源。血液温度的变化可能会在脉搏血氧计和体外血氧计饱和度读数中引入误差，但这些在临床上并不显著。血液pH值的变化不应降低脉搏血氧测定法的准确性。
