Recovery of memory retention after anesthesia with remimazolam: an exploratory, randomized, open, propofol-controlled, single-center clinical trial

Abstract

Purpose Remimazolam, a newly developed ultra-short-acting benzodiazepine, provides early recovery of consciousness but its effects on memory recovery are unclear. This study examined memory recovery after emergence from general anesthesia using remimazolam. Methods Seventy-four patients undergoing breast surgery between October 2021 and March 2022 were enrolled and randomly assigned to receive propofol (control group) or remimazolam as general anesthetic during surgery. The primary endpoint was the number of posters patients remembered 24 h after surgery (among four posters shown after recovering from anesthesia) as an assessment of memory retention. The secondary endpoints were the recall of a numeric character patients had been shown just before anesthetic induction, as an assessment of retrograde amnesia 24 h after surgery. Results Sixty-six patients (propofol, 32; remimazolam, 34) were assessed. Patients in the remimazolam group remembered significantly fewer posters shown to them after surgery than those in the propofol group (0 [0 − 2] vs. 2 [1 − 3], p < 0.001). In the remimazolam group, the patients who received flumazenil remembered a higher number of posters than those who did not receive flumazenil (3 [1 − 4] vs. 0 [0 − 0], p < 0.001). All patients remembered all events that occurred during the preoperative period as well as the numeric character. Conclusion Patients recovering from remimazolam anesthesia without receiving flumazenil do not remember events after regaining consciousness. IRB Kyushu University School of Medicine Hospital Institutional Review Board (IRB) (approval number: 20212006). Trial registration This clinical trial was registered with the University Hospital Medical Information Network (UMIN) Center on September 28, 2021 (UMIN-CTR: UMIN000045593). Implication statement Memory recovery is slower following emergence from remimazolam than from propofol anesthesia.

Remimazolam Pilot for Office-Based Dental Sedation: Adverse Events, Awareness and Outcomes

“…Our induction time, procedure time and time to meet discharge criteria was relatively short, lending itself to the officebased setting. We did not reverse any of the patients with flumazenil, a practice often utilized in order to expedite awakening and return of psychomotor function and memory retention [38,39]. Although we did not report any significant adverse events in this pilot study, it is possible that larger studies are needed to detect occurrences of sentinel, life threatening adverse events which occur at a low incidence.…”

An ultra-short-acting benzodiazepine in thalamic nucleus reuniens undermines fear extinction via intermediation of hippocamposeptal circuits

“…Remimazolam as a novel ultrashort-acting benzodiazepine possesses a distinctive pharmacological profile that remains partially understood, particularly in vivo. While it demonstrates remarkable efficacy as an anesthetic in clinical settings, individuals recovering from remimazolam-induced anesthesia often experience robust amnesia even after consciousness is restored 68 . However, there is a lack of consistent animal studies 69 , 70 addressing the effects of remimazolam on general learning and memory, highlighting the need for further research to elucidate its intricate impacts on mnemonic processes.…”

Comparison of Remimazolam–Flumazenil versus Propofol for Recovery from General Anesthesia: A Systematic Review and Meta-Analysis

“…Following the removal of 35 duplicate records through automated and manual methods, an additional 41 records were excluded after reviewing their titles and abstracts, as they did not meet the inclusion criteria. Upon reviewing the full-text articles of the remaining records, we excluded 13 studies for various reasons: they were not randomized controlled trials [32][33][34][35][36][37], did not set up a propofol group [38,39], did not have routine flumazenil usage in the remimazolam group [19,[40][41][42], or did not have outcomes we wanted [43]. Ultimately, nine studies meeting the criteria were included [44][45][46][47][48][49][50][51][52].…”

“…set up a propofol group [38,39], did not have routine flumazenil usage in the remimazolam group [19,[40][41][42], or did not have outcomes we wanted [43]. Ultimately, nine studies meeting the criteria were included [44][45][46][47][48][49][50][51][52].…”