Near-infrared spectroscopy devices can measure peripheral tissue oxygen saturation (StO<sub>2</sub>). This study aims to compare StO<sub>2</sub> using INVOS® and different O3™ settings (O3<sup>25:75</sup> and O3<sup>30:70</sup>). Twenty adults were recruited. INVOS® and O3™ probes were placed simultaneously on 1 side of forearm. After baseline measurement, the vascular occlusion test was initiated. The baseline value, rate of deoxygenation and reoxygenation, minimum and peak StO<sub>2</sub>, and time from cuff release to peak value were measured. The parameters were compared using ANOVA and Kruskal-Wallis tests. Bonferroni’s correction and Mann-Whitney pairwise comparison were used for post hoc analysis. The agreement between StO<sub>2</sub> of devices was evaluated using Bland-Altman plots. INVOS® baseline value was higher (79.7 ± 6.4%) than that of O3<sup>25:75</sup> and O3<sup>30:70</sup> (62.4 ± 6.0% and 63.7 ± 5.5%, respectively, <i>p</i> < 0.001). The deoxygenation rate was higher with INVOS® (10.6 ± 2.1%/min) than with O3<sup>25:75</sup> and O3<sup>30:70</sup> (8.4 ± 2.2%/min, <i>p</i> = 0.006 and 7.5 ± 2.1%/min, <i>p</i> < 0.001). The minimum and peak StO<sub>2</sub> were higher with INVOS®. No significant difference in the reoxygenation rate was found between the devices and settings. The time to reach peak after cuff deflation was faster with INVOS® (both <i>p</i> < 0.001). Other parameters were similar. There were no differences between the different O3™ settings. There were differences in StO<sub>2</sub> measurements between the devices, and these devices should not be interchanged. Differences were not observed between O3™ device settings.
Evaluation of Different Near-Infrared Spectroscopy Devices for Assessing Tissue Oxygenation with a Vascular Occlusion Test in Healthy Volunteers
