Goldman J M, Petterson M T, Kopotic R J, Barker S J
Masimo Corporation, 2852 Kelvin Avenue, Irvine, CA 92614, USA.
J Clin Monit Comput. 2000;16(7):475-83. doi: 10.1023/a:1011493521730.
To describe a new pulse oximetry technology and measurement paradigm developed by Masimo Corporation.
Patient motion, poor tissue perfusion, excessive ambient light, and electrosurgical unit interference reduce conventional pulse oximeter (CPO) measurement integrity. Patient motion frequently generates erroneous pulse oximetry values for saturation and pulse rate. Motion-induced measurement error is due in part to widespread implementation of a theoretical pulse oximetry model which assumes that arterial blood is the only light-absorbing pulsatile component in the optical path.
Masimo Signal Extraction Technology (SET) pulse oximetry begins with conventional red and infrared photoplethysmographic signals, and then employs a constellation of advanced techniques including radiofrequency and light-shielded optical sensors, digital signal processing, and adaptive filtration, to measure SpO2 accurately during challenging clinical conditions. In contrast to CPO which calculates O2 saturation from the ratio of transmitted pulsatile red and infrared light, Masimo SET pulse oximetry uses a new conceptual model of light absorption for pulse oximetry and employs the discrete saturation transform (DST) to isolate individual "saturation components" in the optical pathway. Typically, when the tissue under analysis is stationary, only the single saturation component produced by pulsatile arterial blood is present. In contrast, during patient motion, movement of non-arterial components (for example, venous blood) can be identified as additional saturation components (with a lower O2 saturation). When conditions of the Masimo model are met, the saturation component corresponding to the highest O2 saturation is reported by the instrument as SpO2.
The technological strategies implemented in Masimo SET pulse oximetry effectively permit continuous monitoring of SpO2 during challenging clinical conditions of motion and poor tissue perfusion.
描述美西公司开发的一种新型脉搏血氧测定技术和测量模式。
患者运动、组织灌注不良、环境光线过强以及电外科设备干扰会降低传统脉搏血氧仪（CPO）测量的完整性。患者运动经常会产生关于饱和度和脉搏率的错误脉搏血氧测定值。运动引起的测量误差部分归因于一种理论脉搏血氧测定模型的广泛应用，该模型假设动脉血是光路上唯一吸收光的搏动成分。
美西信号提取技术（SET）脉搏血氧测定法从传统的红色和红外光电容积脉搏波信号开始，然后采用一系列先进技术，包括射频和光屏蔽光学传感器、数字信号处理和自适应滤波，以在具有挑战性的临床条件下准确测量SpO2。与通过透射搏动性红光和红外光的比率计算氧饱和度的CPO不同，美西SET脉搏血氧测定法使用一种新的脉搏血氧测定光吸收概念模型，并采用离散饱和度变换（DST）来分离光路上的各个“饱和度成分”。通常，当被分析的组织静止时，光路上仅存在由搏动性动脉血产生的单一饱和度成分。相比之下，在患者运动期间，非动脉成分（例如静脉血）的移动可被识别为额外的饱和度成分（氧饱和度较低）。当满足美西模型的条件时，仪器将报告与最高氧饱和度对应的饱和度成分作为SpO2。
美西SET脉搏血氧测定法中实施的技术策略有效地允许在运动和组织灌注不良的具有挑战性的临床条件下持续监测SpO2。
