Pichler Gerhard, Grossauer Karin, Peichl Elisabeth, Gaster Andrea, Berghold Andrea, Schwantzer Gerold, Zotter Heinz, Müller Wilhelm, Urlesberger Berndt
Medical University of Graz, Department of Pediatrics, Division of Neonatology, Auenbruggerplatz 30, 8036 Graz, Austria.
J Biomed Opt. 2009 Jan-Feb;14(1):014014. doi: 10.1117/1.3076193.
One of the problems of near-infrared-spectroscopy (NIRS) measurements is low reproducibility. The aim of the present study was to introduce quality criteria to increase reproducibility of peripheral NIRS measurements. In a prospective cohort study in 40 neonates, repeated NIRS measurements were performed on the calf. During five "reapplication" periods (of NIRS optodes), five "measurements" (venous occlusions) were performed. Tissue oxygenation index (TOI), mixed venous oxygenation (SvO2), fractional oxygen extraction (FOE), hemoglobin flow (Hbflow), oxygen delivery (DO2), and oxygen consumption (VO2) were assessed. Measurements with linear changes during venous occlusions were included for further analysis (first quality criterion: R(2)>0.95). The second quality criterion was the equation 0 < or = TOI-SvO2 < or = (SaO2-SvO2)x0.2. Variance components and mean standard deviations were analyzed after introduction of the quality criteria. Variance components of reapplication and measurement decreased after introduction of the second quality criterion (TOI: 46.6-35.0%, SvO2: 76.8-38.2%, FOE: 73.1-37.5%, Hbflow: 70.3-51.9%, DO2: 71.5-52.7%, and VO2: 70.9-63.8%). Mean standard deviations of TOI (6.6+/-3.0 to 4.7+/-3.2%), SvO2 (11.1+/-4.8 to 5.7+/-3.9%), FOE (11.3+/-4.8 to 5.9+/-4.0%), Hbflow (4.3+/-2.0 to 2.9+/-1.6 micromol100 mLmin), and DO2 (17.8+/-7.6 to 11.4+/-6.2 micromol100 mLmin) decreased significantly, too. Only 12% of measurements fulfilled both quality criteria. With the introduction of two quality criteria, test-retest variability of peripheral NIRS measurements decreased significantly and reproducibility increased significantly.
近红外光谱（NIRS）测量的问题之一是重现性低。本研究的目的是引入质量标准以提高外周NIRS测量的重现性。在一项针对40名新生儿的前瞻性队列研究中，对小腿进行了重复的NIRS测量。在NIRS光极的五个“重新应用”阶段中，进行了五次“测量”（静脉闭塞）。评估了组织氧合指数（TOI）、混合静脉氧合（SvO2）、氧提取分数（FOE）、血红蛋白流量（Hbflow）、氧输送（DO2）和氧消耗（VO2）。纳入静脉闭塞期间呈线性变化的测量值进行进一步分析（第一个质量标准：R(2)>0.95）。第二个质量标准是等式0≤TOI - SvO2≤(SaO2 - SvO2)×0.2。引入质量标准后分析了方差成分和平均标准差。引入第二个质量标准后，重新应用和测量的方差成分降低（TOI：46.6 - 35.0%，SvO2：76.8 - 38.2%，FOE：73.1 - 37.5%，Hbflow：70.3 - 51.9%，DO2：71.5 - 52.7%，VO2：70.9 - 63.8%）。TOI（6.6±3.0至4.7±3.2%）、SvO2（11.1±4.8至5.7±3.9%）、FOE（11.3±4.8至5.9±4.0%）、Hbflow（4.3±2.0至2.9±1.6 μmol/100 mL/min）和DO2（17.8±7.6至11.4±6.2 μmol/100 mL/min）的平均标准差也显著降低。只有12%的测量符合两个质量标准。通过引入两个质量标准，外周NIRS测量的重测变异性显著降低，重现性显著提高。
