Comparison of the Effects of Remimazolam and Sevoflurane on Intraoperative Hemodynamics in Patients Undergoing Off-Pump Coronary Artery Bypass Surgery: A Retrospective Observational Study

Purpose This study was conducted to compare the efficacy and safety of remimazolam with those of sevoflurane in patients undergoing off-pump coronary artery bypass (OPCAB) surgery. Methods This study was a single-center, retrospective observational study. Adult patients who underwent OPCAB surgery between April 2023 and July 2024 and received sevoflurane or remimazolam for maintenance of general anesthesia were included. The primary outcome was intraoperative average blood pressure (ABP). Secondary outcomes were amounts of norepinephrine and other vasopressors used during surgery, intraoperative heart rate (HR), fluid balance, central venous O₂ saturation (S_CVO₂), score of Intensive Care Delirium Screening Checklist (ICD-SC) during the intensive care unit (ICU) stay, occurrence of postoperative acute kidney injury (AKI) and duration of ICU stay. All postoperative complications during the hospitalization period were evaluated. Results Thirty-six patients were included. Eighteen patients were administered remimazolam and 18 patients were administered sevoflurane for maintenance of general anesthesia. Intraoperative ABP was significantly higher in the remimazolam group than in the sevoflurane group (73±4 mmHg vs 69±6 mmHg, <i>P</i>=0.015). The amount of intraoperative norepinephrine was significantly smaller in the remimazolam group than in the sevoflurane group (910±638 μg vs 2041±927 μg, <i>P</i><0.001). There were no differences in other outcomes and incidences of postoperative complications. Conclusion In OPCAB surgery, patients who received remimazolam for maintenance of general anesthesia achieved significantly higher average blood pressure than those who received sevoflurane, even though the amount of intraoperative norepinephrine was significantly smaller in the patients who received remimazolam than in the patients who received sevoflurane.