AI-supported non-invasive measurement for intraoperative hypotension reduction in major orthopedic and trauma surgery : study protocol for a randomized clinical trial

Background: Intraoperative hypotension (IOH) is a common complication in non-cardiac surgeries, with significant impacts on postoperative outcomes such as acute kidney injury (AKI), myocardial injury after non-cardiac surgery (MINS), and postoperative cognitive dysfunction (delirium). Traditional non-invasive blood pressure monitoring often results in blind gaps through the discontinuous measurement, potentially missing critical hypotensive events. This study investigates the efficacy of a non-invasive, continuous AI-supported technology using the Hypotension Prediction Index (HPI) system, designed to predict and mitigate IOH, in reducing the incidence and severity of IOH and related complications in major orthopedic and trauma surgeries. Methods/design: This monocentric, randomized, prospective interventional trial will be conducted at the University Hospital Giessen. The study will include patients aged 45 years and older undergoing major orthopedic or trauma surgeries. Participants will be randomized into two groups: an intervention group receiving hemodynamic management using the ClearSight system in combination with a HPI-based treatment algorithm and a control group receiving standard care. The patients from the standard group also receive continuous cardiac output monitoring; however, this will be blinded to the anesthesiologist, to ensure the comparability of the measured hemodynamic parameters. The primary endpoint is the incidence, duration and severity of IOH, which is defined as MAP < 65 mmHg for at least one minute and which is calculated as the area under MAP < 65 mmHg and the time-weighted average (TWA) of MAP < 65 mmHg. Secondary endpoints include the occurrence of postoperative AKI (measured by KDIGO criteria), MINS (measured by high-sensitivity troponin I assays), and postoperative delirium. The study aims to recruit 150 patients, accounting for potential dropouts, to provide sufficient power to detect differences in the primary and secondary endpoints. Conclusion: This study aims to demonstrate improved intraoperative hemodynamic stability, with a reduction of hypotension and a reduced incidence of postoperative complications, potentially setting a new standard for non-invasive continuous monitoring in orthopedic and trauma patients.