Objective evaluation of facial flushing for mesenteric traction syndrome diagnosis during laparotomy: a prospective observational pilot study.

BACKGROUND: We aimed to evaluate the concordance between facial flushing assessment using an objective color sensor and subjective visual assessment in patients with mesenteric traction syndrome (MTS), to inform the design of a future large-scale study that incorporates objective diagnostic tools. METHODS: In this prospective pilot study, we enrolled adult patients who underwent pancreatectomy. Anesthesiologists assessed the degree of facial flushing subjectively using a scale of levels 0–2. Simultaneously, the Nix color sensor objectively measured the facial redness (a-value) at four facial points. Heart rate and arterial blood pressure were also recorded. Based on the anesthesiologist’s diagnosis, patients were categorized into either the MTS or non-MTS group. We compared the ratio of changes in a-value, heart rate, and blood pressure between the two groups, and their thresholds were also calculated. RESULTS: We included 38 patients: 14 in the MTS group and 24 in the non-MTS group. The MTS group showed significantly higher median change ratio in a-value (0.45 vs. 0.25, P = 0.02) and heart rate (0.45 vs. 0.23, P < 0.01) and a greater decrease in mean arterial pressure (-0.26 vs. -0.14, P = 0.01) than the non-MTS group. Subjective flushing levels correlated with MTS diagnosis (P < 0.01). While the Nix sensor detected flushing in some subjectively undiagnosed cases, one patient in the non-MTS group met all three objective thresholds. CONCLUSION: Objective evaluation of facial flushing using a color sensor is feasible and may enhance conventional assessment methods. To further improve the accuracy of objective evaluation, this pilot study may lead to a larger-scale study including blood tests.