Comparison of remimazolam and sevoflurane on requirement of inotropes and vasopressors in cardiopulmonary bypass surgery: a propensity-score-matched retrospective cohort study

BACKGROUND: There are no data showing that remimazolam can mitigate circulatory inhibition after cardiopulmonary bypass. We investigated whether remimazolam reduced the requirement of vasoactive agents compared with sevoflurane in cardiac patients. METHODS: Cardiac patients who underwent cardiopulmonary bypass surgery between May 2021 and April 2024 were reviewed. Patients who received remimazolam were matched with those who received sevoflurane using propensity scores in a 1:1 ratio. The primary outcome was overall incidence of inotrope and vasopressor infusion. The secondary outcome included ventilation time, duration of intensive care unit (ICU), hospital mortality, and changes in mean arterial pressure and heart rate. RESULTS: Among 276 patients, 100 remained after the matching. Intraoperative use of dobutamine was lower in the remimazolam group than in the sevoflurane group (12% and 92%, respectively, P<0.001). Additionally, noradrenaline was administered less frequently in the remimazolam group (56% and 96%, respectively, P<0.001). Despite less use of vasoactive agents, mean arterial pressure after cardiopulmonary bypass was significantly higher in the remimazolam group. Upon ICU admission, the ratio of patients receiving dobutamine and noradrenaline was also lower in the remimazolam group. The ventilation times tended to be shorter in the remimazolam group, but there were no differences in ICU stay durations and in-hospital deaths between two groups. CONCLUSIONS: Remimazolam use was associated with a reduced need for inotrope and vasopressor after cardiopulmonary bypass. However, no improvements in clinical outcomes were observed. Prospective studies are required to verify whether remimazolam is preferable to conventional anesthetics during cardiac surgery.