Comparison of bispectral index and patient state index as measures of sedation depth during surgeries using remimazolam tosilate

Electroencephalographic and Cardiovascular Assessments of Isoflurane-Anesthetized Dogs

This study investigated the use of frontal electroencephalography (EEG) to monitor varying levels of isoflurane anesthesia in dogs. The patient state index (PSI), burst suppression ratio (SR), and waveforms, were continuously recorded while mean arterial blood pressure (MBP), heart rate, responses to electric stimuli, and subjective anesthetic "depth" were assessed every 3 min. At deep anesthesia (2.5× MAC - 3.2%), the PSI (6.5 ± 10.8) and MBP (45.6 ± 16.4 mmHg) were the lowest, and SR was the highest (78.3 ± 24.0%). At 1× MAC (1.3%), the PSI and MBP increased significantly to 47.8 ± 12.6 and 99.8 ± 13.2, respectively, and SR decreased to 0.5 ± 2.5%. The EEG was predominantly isoelectric at 2×-2.5× MAC, indicating unconsciousness and unresponsiveness. As anesthesia lightened, waveforms transitioned to flatter and faster activity patterns with a response to noxious stimuli, suggesting regained consciousness. The PSI and MBP exhibited a stronger correlation (ρ = 0.8098, p = 0.001) than the relationship of PSI with heart rate (ρ = -0.2089, p = 0.249). Five of the six dogs experienced rough recovery, possibly due to high SR and low MBP. These findings suggest that EEG monitoring in dogs can be a valuable tool for the real-time tracking of brain states and can be used to guide the management of isoflurane anesthesia.

Electroencephalographic Features of Elderly Patients during Anesthesia Induction with Remimazolam: A Substudy of a Randomized Controlled Trial

BACKGROUND

Although remimazolam is used as a general anesthetic in elderly patients due to its hemodynamic stability, the electroencephalogram characteristics of remimazolam are not well known. The purpose of this study was to identify the electroencephalographic features of remimazolam-induced unconsciousness in elderly patients and compare them with propofol.

METHODS

Remimazolam (n = 26) or propofol (n = 26) were randomly administered for anesthesia induction in surgical patients. The hypnotic agent was blinded only to the patients. During the induction of anesthesia, remimazolam was administered at a rate of 6 mg · kg-1 · h-1, and propofol was administered at a target effect-site concentration of 3.5 μg/ml. The electroencephalogram signals from eight channels (Fp1, Fp2, Fz, F3, F4, Pz, P3, and P4, referenced to A2, using the 10 to 20 system) were acquired during the induction of anesthesia and in the postoperative care unit. Power spectrum analysis was performed, and directed functional connectivity between frontal and parietal regions was evaluated using normalized symbolic transfer entropy. Functional connectivity in unconscious processes induced by remimazolam or propofol was compared with baseline. To compare each power of frequency over time of the two hypnotic agents, a permutation test with t statistic was conducted.

RESULTS

Compared to the baseline in the alpha band, the feedback connectivity decreased by averages of 46% and 43%, respectively, after the loss of consciousness induced by remimazolam and propofol (95% CI for the mean difference: -0.073 to -0.044 for remimazolam [P < 0.001] and -0.068 to -0.042 for propofol [P < 0.001]). Asymmetry in the feedback and feedforward connectivity in the alpha band was suppressed after the loss of consciousness induced by remimazolam and propofol. There were no significant differences in the power of each frequency over time between the two hypnotic agents (minimum q value = 0.4235).

CONCLUSIONS

Both regimens showed a greater decrease in feedback connectivity compared to a decrease in feedforward connectivity after loss of consciousness, leading to a disruption of asymmetry between the frontoparietal connectivity.

EDITOR’S PERSPECTIVE

The dose of remimazolam combined with sufentanil for the induction of general anesthesia in obese patients undergoing bariatric surgery: an up-and-down sequential allocation trial

Background and purpose: Remimazolam is a newly developed benzodiazepine drug with water-soluble, esterase degradation, and ultra-short-acting properties. The dose for general anesthesia induction in obese patients was not known. This study aimed to determine the optimal dose of remimazolam in combination with sufentanil for the induction of general anesthesia in obese patients. Methods: It was a prospective observational study. We recruited 46 patients scheduled for bariatric surgery from October 2022 to December 2023. One patient refused to provide informed consent, and six patients were receiving psychotropic medication. Thirty-nine patients were enrolled. The Modified Observer's Assessment of Alertness/Sedation (MOAA/S) scale was used to assess the patient's response. The dose of sufentanil was 0.5 µg/kg (lean body weight [LBW]). The initial dose of remimazolam was 0.3 mg/kg (LBW). The dose of remimazolam was modified using the up-and-down allocation technique. Successful sedation (negative group) was characterized by achieving a MOAA/S score ≤ 1 within 3 min of commencing remimazolam infusion. If negative, the next patient received a low-level dose at a ratio of 0.9. Failed sedation (positive group) was defined as a MOAA/S score of >1 within 3 min of commencing remimazolam infusion. The patients in the positive group received propofol 0.5 mg/kg as a remedial measure, and the next dose was increased to a higher level. The primary outcome was to determine the half-effective dose (ED50) and 95% effective dose (ED95) of remimazolam in combination with sufentanil 0.5 µg/kg for induction in obese patients. The secondary outcome was to determine the occurrence of adverse effects such as hypotension, hypertension, and intraoperative awareness. Results: The ED50 and ED95 values of remimazolam (LBW) combined with sufentanil (0.5 µg/kg) (LBW) were 0.115 mg/kg (95% CI: 0.072-0.137) and 0.179 mg/kg (95% CI: 0.150-0.434), respectively, and the time of loss of consciousness in the negative group was 120.13 ± 25.03 s. The cardiovascular system was stable during the induction period. The incidence of post operative nausea and vomiting (PONV) was 38.5% in 39 patients. Respiratory depression, allergic reaction, intraoperative awareness, and delayed emergence were not observed in any patient. Conclusion: Remimazolam combined with sufentanil (0.5 µg/kg) (LBW) can be effectively used for general anesthesia induction in obese patients. The ED50 and ED95 values of remimazolam (LBW) were 0.115 mg/kg and 0.179 mg/kg, respectively. Clinical Trial Registration: www.chictr.org.cn, identifier ChiCTR2200065602.

Comparative Efficacy of Intraoperative Patient State Index vs. Bi-Spectral Index in Patients Undergoing Elective Spine Surgery with Neuromonitoring Under General Anaesthesia: A Randomized Controlled Trial

Objective

Various electroencephalogram-based monitors have been introduced to objectively quantify anaesthesia depth. However, limited data are available on their comparative clinical efficacy in various surgical procedures. Therefore, we planned this study to compare the relative efficacy of patient state index (PSI) vs. Bi-spectral index (BIS) assessment in patients undergoing elective spine surgery under general anaesthesia.

Methods

This prospective, parallel-group, single-center study included patients undergoing major spine surgery with neuromonitoring. Patients were randomized into two groups, i.e., group B (undergoing surgery under BIS monitoring) and group P (undergoing surgery under PSI monitoring). The primary objective was to compare the time to eye opening after stopping anaesthetic drug infusions.

Results

The mean propofol dose required for induction in group B was 130.45±26.579, whereas that in group P, it was 139.28±17.86 (P value 0.085). The maintenance doses of propofol and fentanyl required for surgery were also comparable between the groups. Time to eye opening was 12.2±4.973 in group B and 12.93±4.19 in group P, with a P value of 0.2664 (U-statistic-684.50).

Conclusion

The intraoperative PSI and BIS had similar clinical efficacy in terms of the dose of propofol required for induction, time of induction, maintenance dose of propofol and fentanyl, time of eye opening, and recovery profile in patients undergoing elective spine surgery under neuromonitoring.

Remimazolam anesthesia in pediatric patients undergoing cardiac catheterization for congenital heart disease: a retrospective observational study

BACKGROUND

Benzodiazepines are used in pediatric patients with congenital heart disease (CHD) because of their mild hemodynamic depressant effects. A novel short-acting benzodiazepine, remimazolam, is expected to be suitable for these patients. We examined the characteristics of remimazolam anesthesia in pediatric patients with CHD undergoing cardiac catheterization.

METHODS

This single-center retrospective study included pediatric patients undergoing cardiac catheterization for CHD. The primary outcome was the remimazolam dose for loss of consciousness. Secondary outcomes included the mean maintenance remimazolam dose, recovery time from anesthesia, predicted remimazolam concentration at emergence, decrease in blood pressure and heart rate, vasopressor administration during anesthesia, electroencephalogram index (bispectral index: BIS or patient state index: PSI), and life-threatening adverse events.

RESULTS

Thirty-nine patients, aged 2 months to 16 years, were included. Thirty-three patients received a median [interquartile] midazolam dose of 0.10 [0.10-0.10] mg.kg-1 in the pre-anesthesia room. The remimazolam dose for loss of consciousness was 0.34 [0.26-0.45] mg.kg-1. The mean maintenance dose was 1.0 [0.8-1.4] mg.kg-1.h-1. The recovery time was 15 [12-17] min. The predicted remimazolam concentration at emergence was 0.4-1.2 µg.ml-1 in 3-6-year-old patients. Blood pressure and heart rate decreased by 30% in 15 and 6 patients, respectively. Vasopressors were administered as a bolus in 8 patients. The BIS or PSI did not fall ≤ 60 or ≤ 50, respectively, in 51% of patients before tracheal intubation. No life-threatening adverse events were reported.

CONCLUSIONS

Remimazolam is a good alternative anesthetic agent for pediatric patients undergoing cardiac catheterization for CHD.

Remimazolam Use in Cardiac Anesthesia: A Narrative Review

Remimazolam, a novel ultra-short-acting intravenous benzodiazepine, has garnered recent attention for its use as a general anesthetic. This narrative review aims to summarize and analyze the available literature on the effects of remimazolam use in cardiac surgical patients, including its effects on hemodynamics, safety in patients with baseline myocardial dysfunction, and impact on postoperative management including time to emergence and extubation. Finally, there is discussion regarding potential drawbacks of adopting remimazolam as a routine anesthetic for cardiac surgery.

Determination of the effective dose of remimazolam combined with sufentanil for inhibiting body movement during surgical abortion: An up-and-down sequential allocation trial

BACKGROUND

Remimazolam, a recently developed anesthetic characterized by its rapid and ultra-short-acting properties, exhibits pharmacological attributes that make it potentially suitable for painless surgical abortion procedures. The objective of this study was to determine the effective dose of remimazolam when administered in combination with sufentanil, with the intention of inhibiting body movement during surgical abortion. Additionally, a secondary objective was to assess the recovery profile from general anesthesia.

METHODS

The study enrolled a total of 25 healthy women aged 20 to 40, with a body mass index between 18 and 28 kg/m2, in their first trimester of pregnancy (up to 12 weeks), and American Society of Anesthesiologists status I and II. Anesthesia induction was initiated by administering sufentanil at a dose of 0.1 μg/kg. The modified Dixon up-and-down method was employed to determine the induction dose of remimazolam for each patient.

RESULTS

The 50% and 95% effective dose of remimazolam for inhibitory effects of body movement was estimated using centered isotonic regression to be 0.145 mg/kg (95% CI: 0.115, 0.207), and 0.242 mg/kg (95% CI: 0.232, 0.620), respectively. Five out of 25 (20%) experienced hiccups, with 1 patient having persistent hiccups until the end of the surgery. The mean time to first eye-opening was 51.4 ± 20.5 seconds, and the time to obey verbal command was 54.5 ± 20.6 seconds. Upon arrival at the postanesthesia care unit, 95.7% of the patients achieved a Modified Aldrete score ≥ 9.

CONCLUSIONS

The 50% and 95% effective dose of remimazolam for inhibiting body movement during surgical abortion when used in combination with 0.1 μg/kg of sufentanil were 0.145 mg/kg and 0.242 mg/kg, respectively.

Comparison of remimazolam tosilate and propofol during induction and maintenance of general anesthesia in patients undergoing laparoscopic cholecystectomy: a prospective, single center, randomized controlled trial

BACKGROUND

Remimazolam tosilate (RT) is a new, ultrashort-acting benzodiazepine. Here, we investigated the efficacy and safety of RT for general anesthesia in patients undergoing Laparoscopic Cholecystectomy (LC).

METHODS

In this study, 122 patients undergoing laparoscopic cholecystectomy were randomly allocated to receive either remimazolam tosilate (Group RT) or propofol group (Group P). RT was administered as a slow bolus of 0.3 mg kg- 1 for induction, followed by 1.0-2.0 mg kg- 1 h- 1 for maintenance of general anesthesia. Propofol was started at 2 mg kg- 1 and followed by 4-10 mg kg- 1 h- 1 until the end of surgery. The primary outcome was the time to bispectral index (BIS) ≤ 60. The secondary outcome included the time to loss of consciousness (LoC), and the time to extubation. Adverse events were also assessed.

RESULTS

A total of 112 patients were recruited for study participation. Among them, the time to BIS ≤ 60 in Group RT was longer than that in Group P (Group RT: 89.3 ± 10.7 s; Group P: 85.9 ± 9.7 s, P > 0.05). While the time to LoC comparing remimazolam and propofol showed no statistical significance (Group RT: 74.4 ± 10.3 s; Group P: 74.7 ± 9.3 s, P > 0.05). The time to extubation in Group RT was significantly longer than that in Group P (Group RT: 16.0 ± 2.6 min; Group P: 8.8 ± 4.3 min, P < 0.001). Remimazolam tosilate had more stable hemodynamics and a lower incidence of hypotension during general anesthesia.

CONCLUSIONS

Remimazolam tosilate can be safely and effectively used for general anesthesia in patients undergoing Laparoscopic Cholecystectomy. It maintains stable hemodynamics during induction and maintenance of general anesthesia compared with propofol. Further studies are needed to validate the findings.

TRIAL REGISTRATION

Chictr.org.cn ChiCTR2300071256 (date of registration: 09/05/2023).

Target-controlled infusion of remimazolam effect-site concentration for total intravenous anesthesia in patients undergoing minimal invasive surgeries

Background

Although pharmacokinetic and pharmacodynamic models of remimazolam have been developed, their clinical application remains limited. This study aimed to administer a target-controlled infusion (TCI) of remimazolam at the effect-site concentration (Ce) in patients undergoing general anesthesia and to investigate the relationship of the remimazolam Ce with sedative effects and with recovery from general anesthesia.

Methods

Fifty patients aged 20-75 years, scheduled for minimally invasive surgery under general anesthesia for less than 2 h, were enrolled. Anesthesia was induced and maintained using Schüttler's model for effect-site TCI of remimazolam. During induction, the remimazolam Ce was increased stepwise, and sedation levels were assessed using the Modified Observer's Assessment of Alertness/Sedation (MOAA/S) scale and bispectral index (BIS). Following attainment of MOAA/S scale 1, continuous infusion of remifentanil was commenced, and rocuronium (0.6 mg/kg) was administered for endotracheal intubation. The target Ce of remimazolam and the remifentanil infusion rate were adjusted to maintain a BIS between 40 and 70 and a heart rate within 20% of the baseline value. Approximately 5 min before surgery completion, the target Ce of remimazolam was reduced by 20-30%, and anesthetic infusion ceased at the end of surgery. Nonlinear mixed-effects modeling was employed to develop pharmacodynamic models for each sedation level as well as emergence from anesthesia.

Results

The remimazolam Ces associated with 50% probability (Ce50) of reaching MOAA/S scale ≤4, 3, 2, and 1 were 0.302, 0.397, 0.483, and 0.654 μg/mL, respectively. The Ce50 values for recovery of responsiveness (ROR) and endotracheal extubation were 0.368 and 0.345 μg/mL, respectively. The prediction probabilities of Ce and BIS for detecting changes in sedation level were 0.797 and 0.756, respectively. The sedation scale significantly correlated with remimazolam Ce (r = -0.793, P < 0.0001) and BIS (r = 0.914, P < 0.0001). Age significantly correlated with Ce at MOAA/S1 and ROR.

Conclusion

Effect-site TCI of remimazolam was successfully performed in patients undergoing general anesthesia. The remimazolam Ce significantly correlated with sedation depth. The Ce50 for MOAA/S scale ≤1 and ROR were determined to be 0.654 and 0.368 μg/mL, respectively.

Comparison of efficacy and safety of equivalent doses of remimazolam versus propofol for gastroscopy anesthesia in elderly patients

Remimazolam, a novel intravenous anesthetic, has been proven to be safe and efficacious in the gastroscopy setting among the elderly. However, reports comparing the effectiveness and safety of using equivalent doses of remimazolam with propofol have not been seen. The aim of this study was to compare the sedation efficacy and safety of the 95% effective doses (ED95) of remimazolam versus propofol combined with sufentanil in the gastroscopy setting among the elderly. In the first step of this two-step study, a modified up-and-down method was used to calculate the ED95 of remimazolam and propofol when combined with 0.1 µg/kg sufentanil in inhibiting body movement of elderly patients undergoing gastroscopy. In the second step, ED95 of both agents calculated in the first step were administered, endpoints of efficacy, safety, and incidence of adverse events were compared. A total of 46 individuals completed the first step. The ED95 of remimazolam was 0.163 mg/kg (95% CI 0.160-0.170 mg/kg), and that of propofol was 1.042 mg/kg (95% CI 1.007-1.112 mg/kg). In the second step, 240 patients completed the trial. The anesthetic effective rates of the remimazolam group and the propofol group were 78% and 83%, respectively, with no statistical difference (P = 0.312). Patients in the remimazolam group had more stable circulatory functions (P < 0.0001) and a lower incidence of pain on injection (3.3% vs. 19.5%, P < 0.0001). The incidence of hypotension was low in the remimazolam versus propofol group (15.6% vs. 39.0%, P < 0.0001). Overall adverse event was low in the remimazolam versus propofol group (21.3% vs. 62.7%, P < 0.0001).In this study, we found that when anesthesia was administered to elderly gastroscopy patients based on 95% effective doses of remimazolam and propofol, remimazolam was as effective as propofol, but was safer with a lower incidence of adverse events.Study registration: Chinese Clinical Trial Registry, ChiCTR2000034234. Registered 29/06/2020, https://www.chictr.org.cn .

Comparison of recovery profiles between total intravenous anaesthesia with propofol or remimazolam reversed with flumazenil in patients undergoing breast surgery: A randomised controlled trial

BACKGROUND

Remimazolam, a short acting benzodiazepine, is being used for general anaesthesia. The results of studies comparing recovery after propofol with that of remimazolam are inconsistent. Given that flumazenil reverses the sedative effects of remimazolam, we hypothesised that it would speed up recovery from remimazolam general anaesthesia.

OBJECTIVES

The aim of this trial was to compare the speed of recovery from general anaesthesia between propofol and remimazolam reversed with flumazenil in patients undergoing minimally invasive breast surgery.

DESIGN

Randomised, single-centre, double-blind controlled trial.

SETTING

A tertiary teaching hospital in South Korea from August 2022 to December 2022.

PATIENTS

Adult patients (≥19 years of age) about to undergo general anaesthesia for scheduled breast cancer surgery.

INTERVENTIONS

Patients were randomly allocated to either the propofol or the remimazolam/flumazenil group. The emergence process was monitored by only one anaesthesiologist.

MAIN OUTCOME MEASURES

The primary outcome was the time to eye opening to command during recovery from the general anaesthesia. Time to removal of the supraglottic airway (SGA) time to discharge, and the Riker sedation agitation scale (SAS) score (1 to 4) during emergence were compared as secondary outcomes.

RESULTS

The remimazolam group had a significantly shorter mean time to eye opening than the propofol group [127 ± 51 vs. 314 ± 140 s; mean difference 187 s (95% confidence interval (CI), 133 to 241 s; P  < 0.001]. The remimazolam group also had shorter times to SGA removal [169 ± 51 vs. 366 ± 149 s; mean difference 198 s (95% CI, 140 to 255 s); P  < 0.001] and time to discharge from the operating room [243 ± 55 vs. 449 ± 159 s; mean difference 206 s (95% CI, 145 to 267 s); P  < 0.001]. The SAS scores during emergence also differed significantly, with 1 patient in the propofol group and 25 in the remimazolam group attaining scores of 4 ( P  < 0.001).

CONCLUSION

Administration of remimazolam with flumazenil may be a promising option for patients undergoing breast cancer surgery, providing faster recovery and better SAS scores than propofol during emergence from general anaesthesia.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT05435911).

Remimazolam-based anesthesia in a patient with hypertrophic obstructive cardiomyopathy undergoing radical colorectal cancer surgery: A case report

BACKGROUND

The goal of anesthesia in patients with hypertrophic obstructive cardiomyopathy (HOCM) is to reduce the risk of left ventricular outflow tract obstruction triggered by anesthetics. Remimazolam is a newly developed anesthetic that has been reported to have superior hemodynamic stability. There have been no reports on the completion of non-cardiac surgery with remimazolam in patients with HOCM.

METHODS

Here we report the case of a 49-year-old man diagnosed with hypertrophic obstructive cardiomyopathy who underwent resection of colon cancer with remimazolam and remifentanil anesthesia. A bolus 0.3 mg/kg remimazolam was administered for anesthesia induction, and then adjusted to 2 mg/kg/h to maintain anesthesia. Set the pain threshold index to 50 to auto-control the infusion speed of remifentanil.

RESULTS

No hypotension occurred during anesthesia, and norepinephrine was not administered. After conversion to open surgery, the patient's blood pressure elevated and reduced with urapidil and esmolol.

CONCLUSION

In this patient with HOCM, remimazolam and remifentanil provided adequate anesthesia for induction and maintenance to complete the right hemicolectomy.

Safety and efficacy of remimazolam tosilate combined with low-dose fentanyl for procedural sedation in obese patients undergoing gastroscopy: study protocol for a single-centre, double-blind, randomised controlled trial

INTRODUCTION

Obese patients are susceptible to hypoxaemia during procedural sedation. Propofol combined with low-dose opioids is commonly used as a sedation strategy, but it can exacerbate hypoxaemia by causing cardiopulmonary depression and airway obstruction, especially in obese patients. Remimazolam, a novel ultra-short-acting benzodiazepine, has minimal accumulative effects and less cardiorespiratory depression. This study aims to evaluate the safety and efficacy of combining remimazolam tosilate with low-dose fentanyl as an alternative option for procedural sedation in obese patients undergoing gastroscopy.

METHODS AND ANALYSIS

This randomised controlled trial (RCT) will be conducted in the Endoscopy Centre of the First Affiliated Hospital of Xiamen University, recruiting 174 participants scheduled for painless gastroscopy with a body mass index of 30-39.9 kg×m-2. All patients will be randomly divided into two groups in a 1:1 ratio. The sedation strategy of the intervention group is remimazolam tosilate combined with fentanyl, while the control group is propofol combined with fentanyl. The primary outcome is the incidence of hypoxaemia and the secondary outcomes include the time to ambulation, need for airway manoeuvres and rescue sedation, sleep quality, the incidence of sedation failure, adverse events and the cost of sedatives. All statistical tests will be performed using IBM SPSS V.20.0 statistical software. A p value<0.05 is considered statistically significant.

ETHICS AND DISSEMINATION

This RCT was reviewed and approved by the Ethics Committee of the First Affiliated Hospital of Xiamen University (Scientific Research Ethics Review 2022, No.093). The results will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ChiCTR2200067076.

Safety and efficacy of remimazolam for general anesthesia in elderly patients undergoing laparoscopic cholecystectomy: a randomized controlled trial

Introduction

There is insufficient evidence regarding the efficacy and safety of remimazolam in elderly patients. Therefore, this study evaluated the differences in the anesthesia characteristics and perioperative hemodynamic profiles of elderly patients receiving total intravenous anesthesia with remimazolam or propofol.

Methods

Eighty-four patients aged >65 years with an American Society of Anesthesiologists physical status of I-III were randomly assigned to Group R (receiving remimazolam, n = 42) or Group P (receiving propofol, n = 42). In Group R, remimazolam was initiated at a rate of 6 mg/kg/h until loss of consciousness (LOC) was achieved and maintained at 1 mg/kg/h subsequently. In Group P, 1.0-1.5 mg/kg of propofol was injected for 1 min and maintained at 100 μg/kg/min subsequently. The maintenance infusion rate was adjusted to maintain an appropriate depth of anesthesia until the end of the surgery. The primary outcome was the time to LOC. The depth of anesthesia scores and hemodynamic profiles were recorded perioperatively.

Results

The time to LOC was significantly longer in Group R (120 s) than in Group P (60 s) (p < 0.001). The time to eye-opening (Group R, 10 min; Group P, 10 min; p = 0.056), the incidence of maintenance of hemodynamic changes within 20% of the peri-anesthetic values, and treatments for hemodynamic instability did not differ significantly between the groups. The depth of anesthesia scores did not differ significantly between the groups; however, the scores were higher in Group R than those in Group P before endotracheal intubation. The hemodynamic parameters did not differ significantly at any time point. The time to extubation was longer in Group R (12 min) than that in Group P (10 min) (p = 0.007). Similarly, the time to discharge from the operating room was significantly longer in Group R (15 min) compared to Group P (12 min) (p = 0.018).

Conclusion

Remimazolam does not exhibit a comparable effect to propofol in terms of anesthesia induction and recovery. However, it demonstrates a similar effect to propofol regarding intraoperative anesthesia depth and hemodynamic profile in elderly patients undergoing remifentanil-based total intravenous anesthesia.

Total intravenous anesthesia management with simultaneous use of remimazolam and propofol: A case series of three patients

Remimazolam is an ultra-short-acting benzodiazepine anesthetic agent. Because of pharmacodynamic interactions in the sedation effect between benzodiazepines and propofol, the combination of remimazolam and propofol may allow for a dose reduction of each agent while providing effective sedation for general anesthesia. We experienced three cases in which general anesthesia was induced with remimazolam and maintained with relatively small doses of remimazolam and propofol target-controlled infusion. In all cases, electroencephalogram changes associated with sedation induced by remimazolam were carefully observed during anesthesia induction before administration of propofol. The time required for recovery from anesthesia was 8-13 min. This is the first report in which remimazolam and propofol were concomitantly used for general anesthesia based on the concept of pharmacodynamic interaction. This anesthetic combination may be beneficial in reducing doses of each anesthetic and avoiding delayed recovery from anesthesia, although further study is needed to confirm this.