Response Surface Model Between Remimazolam and Sevoflurane; Comparison of the Minto and the Greco Model
This prospective randomized open-label study aims to investigate the pharmacodynamic interaction between remimazolam and sevoflurane during general anesthesia using response surface modeling. Although remimazolam has favorable hemodynamic stability compared with propofol, its hypnotic effect may be less predictable and poorly correlated with conventional sedation monitoring indices such as the bispectral index (BIS). In clinical practice, remimazolam and sevoflurane are often combined during induction and maintenance of anesthesia; however, the optimal interaction between these agents remains unclear. This study will evaluate whether the interaction between remimazolam and sevoflurane is synergistic, additive, or infra-additive using two representative response surface interaction models: the Minto model and the Greco model. BIS values and predicted effect-site concentrations will be analyzed using NONMEM software.
• Adults aged 20 to 80 years
• Scheduled for elective surgery under general anesthesia at Pusan National University Yangsan Hospital
• American Society of Anesthesiologists (ASA) physical status I or II
• Able to provide written informed consent