Remimazolam Versus Propofol for Maintenance of Anaesthesia During Major Hepatectomy Under Low Central Venous Pressure

Low central venous pressure management is commonly used during major hepatectomy toreduce bleeding from the hepatic veins. However, fluid restriction and the effects ofgeneral anesthetics may increase the risk, depth, or duration of intraoperativehypotension. Remimazolam may cause less hypotension than propofol, but evidence duringmajor hepatectomy under low central venous pressure management remains limited.This is an investigator‐initiated, single‐center, two‐arm, parallel‐group, randomizedsuperiority trial. The study will enroll 224 adults scheduled for elective resection ofat least three Couinaud liver segments. Participants will be assigned in a 1:1 ratio toreceive remimazolam or propofol for maintenance of total intravenous anesthesia. Bothgroups will receive a common etomidate‐based induction regimen, the same target depth ofanesthesia, continuous invasive arterial pressure monitoring, and standardized protocolsfor low central venous pressure management and treatment of hypotension.The primary observation period is the complete period of liver parenchymal transectionduring low central venous pressure management. The primary outcome integrates the depthand duration of mean arterial pressure below 65 mmHg during this period. Additionalassessments will examine vasopressor use, blood loss, transfusion, recovery, organcomplications, myocardial injury, and adverse events. Participants will be followedthrough postoperative day 30.The attending anesthesiologist cannot be blinded because remimazolam and propofol differin appearance, preparation, and administration. Participants will remain unaware of theirassigned treatment until postoperative outcome assessment is complete. Postoperativeassessors, arterial pressure data reviewers, clinical outcome adjudicators, and theprimary statistician will remain blinded to treatment allocation.