iThermonitor: A wearable non-invasive high-precision alternative to traditional temperature monitoring in thoracoscopic surgery of lateral decubitus position

In thoracoscopic surgery, temperature monitoring is essential but traditionally relies on invasive methods such as esophageal or rectal thermometry, which risk mucosal injury and patient discomfort. This trial evaluates the iThermonitor, a wireless wearable axillary thermometer, as a non-invasive alternative aiming to minimize procedural trauma while maintaining clinical accuracy. We enrolled 80 adult patients scheduled for thoracoscopic surgery under general anesthesia between December 1, 2023, to May 31, 2024. Axillary temperature (iThermonitor) and lower esophageal temperature (reference standard) were recorded every 3 minutes. The primary endpoint was the agreement between devices (± 0.5 °C). Among 3536 temperature pairs, 93.96% of iThermonitor readings were within ± 0.5 °C of lower esophageal values (95% CI: 91.94–95.85%), with strong correlation (Pearson r = 0.75, P < 0.0001). The device demonstrated high diagnostic accuracy for hypothermia (<36.0 °C; AUC = 0.876). Esophageal probes caused bloodstaining in 73.8% of cases, whereas iThermonitor-related skin redness (45%) resolved postoperatively. The iThermonitor is a reliable and accurate non-invasive alternative to traditional invasive temperature monitoring methods in thoracoscopic surgery. It effectively detects perioperative hypothermia and offers significant patient-centered benefits, including enhanced comfort and safety.