A retrospective comparative study of anesthesia with remimazolam and remifentanil versus dexmedetomidine and remifentanil for transcatheter aortic valve replacement

Remimazolam, an ultrashort-acting benzodiazepine, allows for rapid and reliable arousal. Rapid awakening using remimazolam may be beneficial in transcatheter aortic valve replacement (TAVR), as it allows rapid detection of neurologic deficits. The purpose of this study was to compare arousal time and outcomes between monitored anesthesia care (MAC) with remimazolam and remifentanil and conventional MAC with dexmedetomidine, propofol, and remifentanil. This study was a single center retrospective study. All TAVR cases performed under MAC (MAC-TAVR) at our institution between 2019 and 2021 were included. Patients were classified by anesthesia method into remimazolam and dexmedetomidine groups. Among 258 MAC-TAVR patients, 253 were enrolled. After propensity score matching, 76 patients were assigned to each group. The time from end of drug-administration to arousal [20.0 (16.0, 24.0) min vs. 38.5 (30.0, 56.3) min, p < 0.0001] and the time from attempted-arousal to arousal [1.0 (1.0, 1.0) min vs. 12.5 (3.0, 26.8) min, p < 0.0001] were significantly shorter in the remimazolam group. There was no significant difference in the length of ICU stay [2.0 (2.0, 2.0) days vs. 2.0 (2.0, 2.0) days, p = 0.157] and postoperative hospital stay [6.0 (4.0, 9.0) days vs. 5.0 (4.0, 8.0) days, p = 0.262]. Trial registration: Clinical trial number: R03-123, Registry URL: https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000051635 Registration number: UMIN000045195, Principal investigator's name: Atsuhiro Kitaura, Date of registration: 20 August 2021.