脉搏血氧仪具有连续、无创、快速、准确监测人体动脉血氧饱和度和心率的功能,现已在临床上发挥重要作用。脉搏血氧饱和度检测法结合分光光度测定法和容积描记法2个基本方法,用红光和红外光同时对手指及耳垂等组织照射和检测。红外光和红光的容积描记图的波幅比值,随动脉血氧饱和程度而变化。目前使用的脉搏血氧仪基本上采用的是传统的脉搏血氧饱和度检测方法,由于其结果受到测量原理,测量条件及个体差异等多方面因素影响,精度不能令人满意。文章从动态光谱的观点出发,通过分析传统脉搏血氧测量原理中产生误差的原因,从理论上推导出实现高精度脉搏血氧测量的方法。动态光谱方法在原理上具有抑制或克服个体差异和测量条件对检测光谱影响的优点。采用该方法可以消除脉搏血氧饱和度测量的理论上的绝大部分误差。
The pulse oximeter used to measure patienfs oxygen saturation non-invasively and continuously, has numerous applications in clinic care. The pulse oximetry measurement combines two basic methods, spectrophotometry and photoplethysmography (PPG), The red light and the infrared light are exposed to the ear lobe, finger or other tissue with fluctuation of artery blood, and then detected. The amplitude ratio of the photoplethysmography waveform of red light and infrared light varies with the oxygen saturation of blood. The measuring principle of the pulse oximeter is based on traditional test method, its accuracy is not gratifying due to various factors influencing the measurement result, such as the principle, measuring condition, and individual discrepancy. In the present paper a new pulse oximetry based on dynamic spectroscopy is introduced, It can promote the accuracy of the pulse oximeter evidently. The dynamic spectroscopy method is able to eliminate the interference of individual discrepancy and measuring condition in principle. This new method can eliminate the measurement error of pulse oximetry theoretically.