Background: This prospective method-comparison study evaluated a support-surface-integrated under-mattress contactless sensor during general anaesthesia with spontaneous breathing. Methods: In adult surgical patients, we assessed agreement with standard reference monitors for heart and respiratory rates and examined whether a ventilation-related chest wall movement index tracked within-individual tidal volume changes. To minimise artefacts, the analyses were restricted to periods without clinician contact or visible body movements. Results: Heart rate and respiratory rate agreed with reference monitors within prespecified allowable differences. The ventilation-related index showed moderate directional tracking of tidal volume change. Conclusions: These findings provide foundational evidence of signal validity under controlled intraoperative conditions. Further studies should evaluate accuracy, data availability, and robustness during routine perioperative care, including care interactions and patient movement.
Tanaka et al. (Mon,) studied this question.