Impact of the Combination of Remimazolam and Volatile Anesthetics on Circulatory Dynamics in Free-Flap Reconstruction Surgery for Oral Cancer: A Retrospective Comparison With Desflurane and Sevoflurane

Background Patients who undergo free-flap reconstruction surgery for oral cancer are often elderly and require prolonged surgical procedures, making intraoperative circulatory management critical. We investigated the suitability of combining remimazolam besylate (remimazolam), which has minimal circulatory depressant effects, with inhalational anesthetics for maintenance anesthesia in comparison to maintenance using inhalational anesthetics alone. Methodology A retrospective analysis was conducted of patients who underwent oral tumor resection, neck dissection, and free-flap reconstruction surgery at a single institution between October 1, 2020, and April 30, 2022. Patients were divided into the following three groups according to anesthetic use: remimazolam and desflurane combination (Des+R), desflurane monotherapy (Des), and sevoflurane monotherapy (Sevo). Vital signs, vasopressor use, blood loss, and presence or absence of flap complications requiring reoperation were compared. Results Data from 47 patients (Des+R, n = 14; Des, n = 18; Sevo, n = 15) were analyzed. The mean arterial pressure in Des+R was significantly higher than in Des before reconstruction and higher than in both Des and Sevo during vascular anastomosis. Continuous vasopressor use was significantly less frequent in the Des+R group (pre-reconstruction: 21% vs. 77% and 60%, p = 0.006; vascular anastomosis: 28% vs. 72% and 66%, p = 0.04). Ephedrine use was greater in the Des group (p = 0.02), while phenylephrine use did not differ (p = 0.8). Blood loss was greater in Des+R than in Sevo (p = 0.04). Reoperations due to flap complications (thrombosis, hematoma, necrosis) were performed in Des+R (two patients, three times), Des (three patients, three times), and Sevo (three patients, five times). Conclusions In free-flap reconstruction surgery for oral cancer, the combination of desflurane and remimazolam anesthesia maintained higher blood pressure and stable hemodynamics while reducing vasopressor requirements. Given the small sample size and retrospective design, no definitive conclusions about superiority can be drawn. Well-designed prospective studies with standardized vasopressor protocols and assessment of postoperative flap complications are needed to further evaluate the suitability of this combination.