Abstract
<title>Abstract</title> <p> <bold>Background:</bold> Emergence agitation (EA) remains a common, potentially harmful complication after general anesthesia for prolonged laparoscopic oncologic surgery. Sevoflurane, a widely used inhalational anesthetic, is associated with higher EA risk. Remimazolam, an ultra-short-acting benzodiazepine, may reduce EA owing to favorable hemodynamic stability and a distinct recovery profile compared with sevoflurane. We aim to test whether remimazolam-based total intravenous anesthesia (RTIVA) decreases EA incidence versus sevoflurane-based inhalational anesthesia (SINH). <bold>Methods:</bold> This single-center, assessor-blinded, randomized controlled trial will enroll 108 adults (≥18 years, ASA II–III) scheduled for elective laparoscopic radical resection of gastric or colorectal cancer with expected duration ≥2 hours. Participants will be randomized 1:1 to RTIVA (remimazolam infusion + remifentanil) or SINH (sevoflurane + remifentanil). Perioperative management is standardized across groups. The primary outcome is incidence of EA in the post-anesthesia care unit (PACU), defined as Ricker sedation agitation scale (RSAS) ≥5, assessed by blinded observers from PACU arrival to discharge. Secondary outcomes include severe agitation (RSAS = 7), extubation time, time to BIS ≥80, time to full emergence, PACU length of stay, analgesic/antiemetic needs, use of flumazenil, postoperative nausea/vomiting within 24 h, postoperative delirium during hospitalization, QoR-15 on postoperative day 1, perioperative TNF-α and IL-6, intraoperative hemodynamics, hospital length of stay, and safety events (hypotension, bradycardia, resedation, hypoxemia, intraoperative awareness). <bold>Discussion:</bold> This study will contribute to evaluating the efficacy and safety of remimazolam for preventing EA in patients undergoing laparoscopic radical resection for gastric or colorectal cancer. The results may provide preliminary clinical evidence informing evidence-based anesthetic practice for this high-risk patient group. <bold>Trial registration:</bold> Chinese Clinical Trial Registry, <bold/> ChiCTR2500095670. Registered on January 10, 2025, https://www.chictr.org.cn/showproj.html?proj=256625. </p>