Abstract / Summary
Background and Objectives: Robot-assisted direct-to-implant breast reconstruction involves procedural factors that may affect intraoperative hemodynamics, including prolonged surgery, semi-sitting positioning, and subcutaneous carbon dioxide insufflation. This study compared vasopressor requirements and hemodynamic profiles between remimazolam-based total intravenous anesthesia (TIVA) and propofol–sevoflurane anesthesia. Materials and Methods: This retrospective cohort study included 46 patients who underwent robot-assisted direct-to-implant breast reconstruction. Of these, 20 received propofol–sevoflurane anesthesia, and 26 received remimazolam-based TIVA. The primary outcome was total intraoperative norepinephrine consumption. Secondary outcomes included vasopressor infusion duration, time from induction to vasopressor initiation, incidence of hypotension, hemodynamic profiles analyzed using linear mixed-effects models, postoperative pain scores, and reconstructive outcomes. Results: Total norepinephrine consumption was significantly lower in the remimazolam group than in the propofol–sevoflurane group (median, 123.2 [interquartile range, 62.4–176.4] vs. 580.0 [338.8–790.4] µg; p < 0.001). The remimazolam group also had a shorter vasopressor infusion duration (67.7 ± 40.0 vs. 176.3 ± 66.4 min; p < 0.001), a longer vasopressor-free interval from induction (median, 140 vs. 25 min; log-rank p < 0.001), and a lower incidence of hypotension, defined as mean arterial pressure (MAP) < 65 mmHg (46.2% vs. 80.0%; p = 0.032). After adjustment for age, body mass index, and anesthesia time, remimazolam-based anesthesia remained associated with lower norepinephrine consumption (B = −515.4 µg; p < 0.001). MAP and heart rate (HR) showed no significant between-group differences over time, and neither the estimated duration nor time-weighted average (TWA) below MAP 65 mmHg differed significantly. Conclusions: In this retrospective cohort, a remimazolam-based TIVA strategy was associated with lower recorded intraoperative norepinephrine use than a propofol–sevoflurane strategy. No significant between-group differences in serial MAP or HR were detected. These associations warrant confirmation in prospective trials with standardized protocols.