Reproducibility of glycocheck measurements in patients under general anesthesia with muscle relaxants: A prospective observational study.

purposeTo evaluate the inter- and intraobserver reproducibility of sublingual microcirculatory indices measured using the GlycoCheck system, including the perfused boundary region (PBR), vascular density (VD), and red blood cell filling (RBCF), in patients under general anesthesia without any motion artifacts.

methodsFifty patients who received general anesthesia for laparoscopic gastrointestinal surgery were included in this study. After the induction of general anesthesia, the leading observer and one of the five subobservers took two and one measurements of sublingual microcirculation with the GlycoCheck system, respectively. Inter- and intraobserver reproducibility was assessed using intraclass correlation coefficients (ICC). Interobserver reproducibility was calculated using the first measurements of the leading observer and subobservers, and intraobserver reproducibility was calculated using two consecutive measurements of the leading observer.

resultsThe interobserver reproducibility of a single measurement was poor for all three parameters. The interobserver ICCs for PBR were 0.13 [95% CI: -0.15, 0.39], for VD was - 0.01 [95%CI: -0.29, 0.27], and for RBCF were 0.31 [95%CI: -0.45, 0.78]. The intraobserver ICCs for PBR was 0.32 [95% CI: 0.05, 0.55] for all 50 cases, 0.17 [95% CI: -0.25, 0.53] for the first 25 cases, and 0.46 [95% CI: 0.09, 0.72] for the second 25 cases. The Bland-Altman plots indicated that the measurement errors were random.

conclusionIn patients under general anesthesia, single PBR, VD, and RBCF measurements using the GlycoCheck system showed poor interobserver reproducibility. Although the intraobserver reproducibility of PBR measurements was poor, improving measurement proficiency might improve reproducibility. Further research is required to establish measurement methods that achieve better reproducibility and adequate observer training.