Brain-targeted goal-directed therapy in high-risk patients undergoing major elective surgery: Study protocol for the BRAIN-PROMISE randomized trial

Background: Perioperative complications can lead to increased morbidity and mortality, diminished patient's quality of life, and substantial economic burden. Elderly and frail patients are particularly vulnerable, facing higher risks of postoperative cognitive dysfunction and delirium. Perioperative choices and anaesthesia management, including hemodynamic monitoring, anaesthesia depth, and fluid therapy can significantly impact long-term outcomes. Near-infrared spectroscopy (NIRS) is a technique for measuring regional oxygen saturation of brain tissue (rSO2) during surgery. Monitoring cerebral perfusion through rSO2 could estimate perfusion changes, identify early tissue hypoxia, and mitigate postoperative complications. Nonetheless, there is a lack of studies exploring NIRS-based hemodynamic optimization protocols in high-risk surgical populations. Object: This prospective randomized controlled trial has been designed to evaluate whether NIRS-targeted goaldirected therapy can reduce rSO2 drop episodes and improve outcomes in high-risk elderly patients undergoing major surgery. Methods: This randomized controlled trial will enroll hypertensive elderly patients aged >= 65 or with a clinical frailty score >= 5, undergoing moderate to high-risk surgery under general anaesthesia. Participants will be randomized 1:1 to either NIRS-targeted management or standard care, with NIRS monitoring applied to both groups but only guiding intervention in the experimental group, and with anesthesiologist blinded to NIRS value in control group. Primary outcomes include the overall incidence of perioperative complications at 30 days, secondary outcomes assess cognitive dysfunction, delirium, length of stay and mortality at 90 days. Conclusions: This study presents an innovative approach on the effectiveness of NIRS-targeted goal directed for improving perioperative outcomes in high-risk elderly patients undergoing general anaesthesia. Trial registration: clinicaltrials.gov registration, n. NCT04266574,