Evaluation of Different Near-Infrared Spectroscopy Devices for Assessing Tissue Oxygenation with a Vascular Occlusion Test in Healthy Volunteers

Near-infrared spectroscopy devices can measure peripheral tissue oxygen saturation (StO(2)). This study aims to compare StO(2) using INVOS (R) and different O3 (TM) settings (O3(25:75) and O3(30:70)). Twenty adults were recruited. INVOS (R) and O3 (TM) 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(2), 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(2) of devices was evaluated using Bland-Altman plots. INVOS (R) baseline value was higher (79.7 +/- 6.4%) than that of O3(25:75) and O3(30:70) (62.4 +/- 6.0% and 63.7 +/- 5.5%, respectively, p < 0.001). The deoxygenation rate was higher with INVOS (R) (10.6 +/- 2.1%/min) than with O3(25:75) and O3(30:70) (8.4 +/- 2.2%/min, p = 0.006 and 7.5 +/- 2.1%/min, p < 0.001). The minimum and peak StO(2) were higher with INVOS (R). 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 (R) (both p < 0.001). Other parameters were similar. There were no differences between the different O3 (TM) settings. There were differences in StO(2) measurements between the devices, and these devices should not be interchanged. Differences were not observed between O3 (TM) device settings.