Effect of Remimazolam Tosilate on Respiratory Depression in Elderly Patients Undergoing Gastroscopy: A Multicentered, Prospective, and Randomized Study

Remimazolam for sedation in gastrointestinal endoscopy: A comprehensive review

Worldwide, a majority of routine endoscopic procedures are performed under some form of sedation to maximize patient comfort. Propofol, benzodiazepines and opioids continue to be widely used. However, in recent years, Remimazolam is gaining immense popularity for procedural sedation in gastrointestinal (GI) endoscopy. It is an ultra-short-acting benzodiazepine sedative which was approved by the Food and Drug Administration in July 2020 for use in procedural sedation. Remimazolam has shown a favorable pharmacokinetic and pharmacodynamic profile in terms of its non-specific metabolism by tissue esterase, volume of distribution, total body clearance, and negligible drug-drug interactions. It also has satisfactory efficacy and has achieved high rates of successful sedation in GI endoscopy. Furthermore, studies have demonstrated that the efficacy of Remimazolam is non-inferior to Propofol, which is currently a gold standard for procedural sedation in most parts of the world. However, the use of Propofol is associated with hemodynamic instability and respiratory depression. In contrast, Remimazolam has lower incidence of these adverse effects intra-procedurally and hence, may provide a safer alternative to Propofol in procedural sedation. In this comprehensive narrative review, highlight the pharmacologic characteristics, efficacy, and safety of Remimazolam for procedural sedation. We also discuss the potential of Remimazolam as a suitable alternative and how it can shape the future of procedural sedation in gastroenterology.

Remimazolam has similar anesthetic effect and superior safety compared to propofol in elderly patients: A meta-analysis of randomized controlled trials

BACKGROUND

The superiority between remimazolam and propofol for anesthesia is controversial in elderly patients (≥60 years). This meta-analysis aimed to systematically compare anesthetic effect and safety profile between remimazolam and propofol in elderly patients under any surgery.

METHODS

Cochrane Library, Web of Science, and PubMed were searched until December 25, 2023 for relevant randomized controlled trials.

RESULTS

Ten studies with 806 patients receiving remimazolam (experimental group) and 813 patients receiving propofol (control group) were included. Time to loss of consciousness [standard mean difference (SMD) (95% confidence interval (CI): 1.347 (-0.362, 3.055), p = 0.122] and recovery time [SMD (95% CI): -0.022 (-0.300, 0.257), p = 0.879] were similar between experimental and control groups. Mean arterial pressure at baseline minus 1 min after induction [SMD (95% CI): -1.800 (-3.250, -0.349), p = 0.015], heart rate at baseline minus 1 min after induction [SMD (95% CI): -1.041 (-1.537, -0.545), p < 0.001], incidences of hypoxemia [relative risk (RR) (95% CI): 0.247 (0.138, 0.444), p < 0.001], respiratory depression [RR (95% CI): 0.458 (0.300, 0.700), p < 0.001], bradycardia [RR (95% CI): 0.409 (0.176, 0.954), p = 0.043], hypotension [RR (95% CI): 0.415 (0.241, 0.714), p = 0.007], and injection pain [RR (95% CI): 0.172 (0.113, 0.263), p < 0.001] were lower in the experimental group compared to the control group. Postoperative nausea and vomiting was not different between groups [RR (95% CI): 1.194 (0.829, 1.718), p = 0.341]. Moreover, this meta-analysis displayed a low risk of bias, minimal publication bias, and good robustness.

CONCLUSION

Remimazolam shows comparative anesthetic effect and better safety profile than propofol in elderly patients under any surgery.

ED50 and ED95 of Remimazolam Tosilate Combined with Different Doses of Fentanyl in Elderly Patients for Painless Gastroscopy

Background

The novel short-acting benzodiazepine drug, remimazolam tosilate, has been employed for sedation during endoscopic procedures. The optimal loading dosage of remimazolam tosilate in gastroscopy for elderly patients when co-administered with fentanyl remains unclear. Therefore, the primary objective of our research was to ascertain the median effective dose (ED50) and the 95% effective dose (ED95) of remimazolam tosilate in combination with various fentanyl dosages for elderly patients undergoing painless gastroscopy.

Methods

Seventy-five patients aged ≥65 years and American Society of Anesthesiologists (ASA) class I-III were recruited to undergo elective painless gastroscopy. All patients were randomized assigned to group F1, group F2, and group F3, and were injected intravenously with different doses of fentanyl (0.5 ug/kg, 1 ug/kg, and 1.5 ug/kg) 3 minutes prior to the administration of remimazolam tosilate, respectively. The initial preset dose of remimazolam tosilate was 0.3 mg/kg in group F1, 0.2 mg/kg in group F2, 0.15 mg/kg in group F3. The dose gradient was 0.02 mg/kg per group according to the up-and-down sequential method. Probibt regression model was employed to determine the ED50 and ED95 of remimazolam tosilate.

Results

The ED50 of remimazolam tosilate in group F3 was lower than that in group F1 and F2 (0.095 [0.088-0.108] mg/kg vs 0.162 [0.153-0.171] mg/kg; 0.258 [0.249-0.266] mg/kg, p < 0.05). The ED95 of remimazolam tosilate was 0.272 mg/kg (95% CI: 0.264-0.295 mg/kg) in group F1, 0.175 mg/kg (95% CI: 0.167-0.200 mg/kg) in group F2 and 0.109 mg/kg (95% CI: 0.101-0.135 mg/kg) in group F3. The total dosage of remimazolam tosilate decreased gradually with the increasing of fentanyl (p < 0.001). The frequency of injection pain was higher in group F1 compared to groups F2 and F3 (p < 0.05). The patients in group F3 had a lower incidence of hypotension than in groups F1 and F2 (p < 0.05). There was no respiratory depression, intraoperative consciousness, dizziness or delirium in the three groups.

Conclusion

The concurrent use of fentanyl reduces the dosage of remimazolam tosilate required for sedative gastroscopy in elderly patients in a dose-dependent manner. Moreover, 1.5 ug/kg fentanyl combined with remimazolam tosilate may reduce the incidence of hypotension and injection pain. These findings should be confirmed in a large-scale study.

Remimazolam versus propofol for sedation in gastrointestinal endoscopic procedures: a systematic review and meta-analysis

BACKGROUND

Propofol has a favourable efficacy profile in gastrointestinal endoscopic procedures, however adverse events remain frequent. Emerging evidence supports remimazolam use in gastrointestinal endoscopy. This systematic review and meta-analysis compares remimazolam and propofol, both combined with a short-acting opioid, for sedation of adults in gastrointestinal endoscopy.

METHODS

We searched MEDLINE, Embase, and Cochrane databases for randomised controlled trials comparing efficacy-, safety-, and satisfaction-related outcomes between remimazolam and propofol, both combined with short-acting opioids, for sedation of adults undergoing gastrointestinal endoscopy. We performed sensitivity analyses, subgroup assessments by type of short-acting opioid used and age range, and meta-regression analysis using mean patient age as a covariate. We used R statistical software for statistical analyses.

RESULTS

We included 15 trials (4516 subjects). Remimazolam was associated with a significantly lower sedation success rate (risk ratio [RR] 0.991; 95% confidence interval [CI] 0.984-0.998; high-quality evidence) and a slightly longer induction time (mean difference [MD] 9 s; 95% CI 4-13; moderate-quality evidence), whereas there was no significant difference between the sedatives in other time-related outcomes. Remimazolam was associated with significantly lower rates of respiratory depression (RR 0.41; 95% CI 0.30-0.56; high-quality evidence), hypotension (RR 0.43; 95% CI 0.35-0.51; moderate-quality evidence), hypotension requiring treatment (RR 0.25; 95% CI 0.12-0.52; high-quality evidence), and bradycardia (RR 0.42; 95% CI 0.30-0.58; high-quality evidence). There was no difference in patient (MD 0.41; 95% CI -0.07 to 0.89; moderate-quality evidence) and endoscopist satisfaction (MD -0.31; 95% CI -0.65 to 0.04; high-quality evidence) between both drugs.

CONCLUSIONS

Remimazolam has clinically similar efficacy and greater safety when compared with propofol for sedation in gastrointestinal endoscopies.

Remimazolam versus propofol for sedation in gastrointestinal endoscopy and colonoscopy within elderly patients: a meta-analysis of randomized controlled trials

PURPOSE

Propofol has become the sedative of choice for endoscopy and colonoscopy. However, it has shown associations with various adverse effects, specifically in the geriatric population. In contrast, remimazolam is a novel benzodiazepine, demonstrating a superior clinical safety profile. Hence, this systematic review and meta-analysis aims to clarify the efficacy and safety of remimazolam versus propofol in elderly patients (≥ 60 years) undergoing gastrointestinal endoscopic and colonoscopy procedures.

METHODS

Electronic databases including PubMed, Cochrane Library, ScienceDirect, and Google Scholar were explored from inception till January 7, 2024. The Cochrane Risk of Bias Tool for Randomized Controlled Trials (RoB-2) was utilized to evaluate the quality of each included study reported in this meta-analysis.

RESULTS

Seven randomized control trials were included, resulting in the pooling of 1,466 patients (remimazolam: 731 patients; propofol: 735 patients). Propofol demonstrated a significantly lower time to loss of consciousness (P < 0.00001, 4 studies, 784 patients) and a greater sedation success after first dose (P = 0.05, 5 studies, 1,271 patients). Remimazolam reported a significantly lower risk of bradycardia (P = 0.02, 5 studies, 1,323 patients), hypoxemia (P < 0.00001, 6 studies, 1,389 patients), and pain on injection site (P < 0.00001, 5 studies, 1,184 patients). No statistically significant differences in sedation time, number of supplemental doses, procedural parameters, and other adverse outcomes were reported.

CONCLUSION

As per the results of our analyses, propofol demonstrated comparatively superior efficacy, however, remimazolam demonstrated comparatively superior safety. The debatable evidence generated from this meta-analysis may not currently be powerful enough to advocate for the use of remimazolam in elderly patients undergoing gastrointestinal procedures; hence, further comprehensive studies are necessary in order to arrive at a robust conclusion.

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 .

Safety and efficacy comparison of remimazolam and propofol for intravenous anesthesia during gastroenteroscopic surgery of older patients: A meta-analysis

BACKGROUND

Remimazolam is characterized by rapid action and inactive metabolites. It is used as the general anesthetic for many clinical surgeries. In this study, we performed a meta-analysis to evaluate whether remimazolam is superior to propofol for gastroenteroscopy in older patients.

AIM

To compare the adverse events and efficacy of remimazolam and propofol during gastroenteroscopy in older adults.

METHODS

The PubMed, Web of Science, the Cochrane Library databases were queried for the relevant key words "remimazolam," "and propofol," "and gastrointestinal endoscopy or gastroscopy." The search scope was "Title and Abstract," and the search was limited to human studies and publications in English. Seven studies wherein remimazolam and propofol were compared were included for the meta-analysis.

RESULTS

We selected seven randomized controlled trials involving 1445 cases for the analysis. Remimazolam reduced the hypotension (relative risk, RR = 0.44, 95%CI: 0.29-0.66, P = 0.000), respiratory depression (RR = 0.46, 95%CI: 0.30-0.70, P = 0.000), injection pain (RR = 0.12, 95%CI: 0.05-0.25, P = 0.000), bradycardia (RR = 0.37, 95%CI: 0.24-0.58, P = 0.000), and time to discharge [weighted mean difference (WMD) = -0.58, 95%CI: -0.97 to -0.18, P = 0.005], compared to those after propofol administration. No obvious differences were observed for postoperative nausea and vomiting (RR = 1.09, 95%CI: 0.97-1.24, P = 0.151), dizziness (RR = 0.77, 95%CI: 0.43-1.36, P = 0.361), successful sedation rate (RR = 0.96, 95%CI: 0.93-1.00, P = 0.083), or the time to become fully alert (WMD = 0.00, 95%CI: -1.08-1.08, P = 0.998).

CONCLUSION

Remimazolam appears to be safer than propofol for gastroenteroscopy in older adults. However, further studies are required to confirm these findings.

The safety of remimazolam versus propofol in gastroscopic sedation: a meta-analysis

BACKGROUND

This meta-analysis was designed to compare the safety and efficiency of remimazolam with those of propofol in patients undergoing gastroscope sedation.

METHODS

We searched PubMed, Cochrane Library, Embase, Ovid, Wanfang Database, China National Knowledge Infrastructure, SINOMED, and ClinicalTrials.gov for studies that reported on remimazolam versus propofol for gastroscope sedation from establishment to February 25, 2023. The sedative efficiency and the incidence of adverse events were assessed as outcomes. Version 2 of the Cochrane risk-of-bias assessment tool was used to assess the risk of bias. Review Manager 5.4 and STATA 17 were used to perform all statistical analyses.

RESULTS

A total of 26 randomized controlled trials involving 3,641 patients were included in this meta-analysis. The results showed that remimazolam had a significantly lower incidence of respiratory depression (risk ratio [RR] = 0.40, 95% confidence interval [CI]: 0.28-0.57; p < 0.01, GRADE high), hypoxemia (RR = 0.34, 95% CI: 0.23-0.49; p < 0.01, GRADE high), bradycardia (RR = 0.34, 95% CI: 0.23-0.51; p < 0.01, GRADE high), dizziness (RR = 0.45, 95% CI: 0.31-0.65; p < 0.01, GRADE high), injection site pain (RR = 0.06, 95% CI: 0.03-0.13; p < 0.01, GRADE high), nausea or vomiting (RR = 0.79, 95% CI: 0.62-1.00; p = 0.05, GRADE moderate), and hypotension (RR = 0.36, 95% CI: 0.26-0.48; p < 0.01, GRADE low).

CONCLUSIONS

Remimazolam can be used safely in gastroscopic sedation and reduces the incidence of respiratory depression, hypoxemia, bradycardia, injection site pain, and dizziness compared with propofol, and doesn't increase the incidence of nausea and vomiting.

Remimazolam and Remifentanil Use Induced Severe Respiratory Depression and Laryngeal Spasm During Intravenous Sedation and Analgesia: A Case Report

INTRODUCTION

Intravenous sedation and analgesia are widely used in minor surgeries. Remifentanil and remimazolam are advantageous in this setting because of their rapid onset of action, and short duration of action leading to a rapid recovery. However, the two drugs combined need to be titrated to avoid airway-related adverse events.

CASE PRESENTATION

This article reports a case of severe respiratory depression and severe laryngeal spasm induced by remifentanil and remimazolam when they were used for analgesia and sedation in a patient undergoing oral biopsy.

CONCLUSION

We aim to improve awareness about the safety of these drugs among anesthesiologists and increase their ability to manage the risk associated with their use.

Comparison of oxygen reserve index according to the remimazolam or dexmedetomidine for intraoperative sedation under regional anesthesia-A single-blind randomized controlled trial

Introduction

We aimed to evaluate the difference in intraoperative oxygen reserve index (ORi) between the sedatives remimazolam (RMMZ) and dexmedetomidine (DEX).

Methods

Seventy-eight adult patients scheduled for sedation under regional anesthesia were randomly assigned to either the DEX (n = 39) or RMMZ (n = 39) group. The primary outcome was the difference in perioperative ORi between the groups. The secondary outcomes included respiratory depression, hypo- or hypertension, heart rate (HR), blood pressure, respiratory rate and postoperative outcomes. Additionally, the number of patients who experienced a decrease in intraoperative ORi to < 50% and the associated factors were analyzed.

Results

The ORi was significantly higher in the RMMZ group at 15 min after sedation maintenance. There were no significant differences in respiratory depression between the two groups. The intraoperative HR was significantly higher in the RMMZ group after the induction of sedation, 15 min after sedation maintenance, and at the end of surgery. No other results were significantly different between the two groups. The incidence of a decrease in intraoperative ORi to < 50% was significantly higher in the DEX group. Factors associated with a decrease in the intraoperative ORi to < 50% were diabetes mellitus, low baseline peripheral oxygen saturation (SpO2), and DEX use. In the receiver operating characteristic curve analysis for a decrease in the intraoperative ORi to < 50%, the cutoff baseline SpO2 was 97%.

Conclusion

RMMZ is recommended as a sedative for patients with a low baseline SpO2 and intraoperative bradycardia. Further studies should be conducted to establish the criteria for a significant ORi reduction.

Remimazolam and serious adverse events: A scoping review

Remimazolam is anticipated to be an interesting anaesthetic and sedative. It combines the pharmacodynamic properties of midazolam with pharmacokinetic properties similar to remifentanil. However, worrisome case reports of anaphylaxis, delayed emergence and re-sedation have emerged recently and necessitate further investigation.PubMed (including MEDLINE) and EMBASE were searched for all studies reporting serious adverse events where remimazolam was administered for sedation or anaesthesia.Thirty-six case reports and 73 trials were identified, involving a total of 6740 patients who received remimazolam. Hypotension was reported in 911 cases, delayed emergence in 68 cases, anaphylaxis in 10 cases and re-sedation in 8 cases. The incidence of hypotension seems to be lower compared with other anaesthetics, even in high-risk patients.Delayed emergence might be related to the metabolism of remimazolam through carboxylesterase 1 (CES1), a tissue esterase predominant in the liver. There is significant interindividual variation, and it is inhibited by flavonoids, fatty acids and alcohol. Individual benzodiazepine sensitivity has also been reported. A higher BMI, older age and low plasma albumin concentration are risk factors for delayed emergence. Anaphylaxis might be related to a non-IgE-mediated effect of the excipient dextran-40 or a partially IgE-mediated reaction to remimazolam itself. Resedation has been reported after flumazenil reversal and is explained by the specific pharmacokinetic properties of flumazenil and remimazolam. Reversal by flumazenil should be reserved for and used carefully in patients with delayed emergence.

VISUAL ABSTRACT

http://links.lww.com/EJA/A864 .

Efficacy and safety of remimazolam besilate for sedation in outpatients undergoing impacted third molar extraction: a prospective exploratory study

BACKGROUND

Dental treatments often cause anxiety, fear, and stress in patients. Intravenous sedation is widely used to alleviate these concerns, and various agents are employed for sedation. However, it is important to find safer and more effective sedation agents, considering the adverse effects associated with current agents. This study aimed to investigate the efficacy and safety of remimazolam besilate (hereinafter called "remimazolam") and to determine the optimal dosages for sedation in outpatients undergoing dental procedures.

METHODS

Thirty-one outpatients aged 18-65 years scheduled for impacted third molar extraction were included in the study. Remimazolam was administered as a single dose of 0.05 mg/kg followed by a continuous infusion at a rate of 0.35 mg/kg/h, with the infusion rate adjusted to maintain a sedation level at a Modified Observer's Assessment of Alertness/Sedation (MOAA/S) score of 2-4. The primary endpoint was the sedation success rate with remimazolam monotherapy, and the secondary endpoints included induction time, recovery time, time until discharge, remimazolam dose, respiratory and circulatory dynamics, and frequency of adverse events.

RESULTS

The sedation success rate with remimazolam monotherapy was 100%. The remimazolam induction dose was 0.08 (0.07-0.09) mg/kg, and the anesthesia induction time was 3.2 (2.6-3.9) min. The mean infusion rate of remimazolam during the procedure was 0.40 (0.38-0.42) mg/kg/h. The time from the end of remimazolam administration to awakening was 8.0 (6.7-9.3) min, and the time from the end of remimazolam administration to discharge was 14.0 (12.5-15.5) min. There were no significant respiratory or circulatory effects requiring intervention during sedation.

CONCLUSIONS

Continuous intravenous administration of remimazolam can achieve optimal sedation levels without significantly affecting respiratory or circulatory dynamics. The study also provided guidance on the appropriate dosage of remimazolam for achieving moderate sedation during dental procedures. Additionally, the study findings suggest that electroencephalogram monitoring can be a reliable indicator of the level of sedation during dental procedural sedation with remimazolam.

TRIAL REGISTRATION

The study was registered in the Japan Registry of Clinical Trials (No. jRCTs061220052) on 30/08/2022.

Procedural sedation analgesia in the elderly patient

Elderly patients are perceived as a high-risk group for procedural sedation. Procedural sedation analgesia (PSA) is generally safe in older adults. What is not acceptable is undertreating pain or inadequately sedating a stable patient. All the usual precautions should be taken. One should consider any comorbidities that could make the patient more at risk of adverse reactions or complications. Older patients may be at higher risk for oxygen desaturation, but they usually respond quickly to supplemental oxygen. Geriatric patients usually require lower doses of medications. They tend to be more sensitive to medications, with slower metabolism, less physiologic reserve to handle side effects, and a smaller volume of distribution. The use of drugs for sedation in elderly patients requires careful consideration of their age-related changes in physiology and pharmacokinetics. The choice of drug should be based on the patient's medical condition, comorbidities, and potential adverse effects. Moreover, the administration should be done by trained personnel with close monitoring of vital signs and level of consciousness to prevent complications such as respiratory depression.

Remimazolam for Sedation During Fiberoptic Intubation in an Adolescent

In specific clinical scenarios, fiberoptic intubation (FOI) may be the preferred technique for airway management and endotracheal intubation. In addition to topical anesthesia of the airway, sedation is frequently necessary, especially in younger patients, to facilitate the procedure. The goal is to facilitate the procedure by providing sedation, anxiolysis, and analgesia with maintenance of spontaneous ventilation. Remimazolam is a novel benzodiazepine with a short half-life and limited context sensitive half-life that can be titrated by continuous infusion. These novel properties may make it a suitable agent for sedation during FOI of the trachea. We report the novel use of a combination of remimazolam and remifentanil infusions to provide sedation during FOI in an adolescent. The basic pharmacology of remimazolam is presented and previous reports of its use for sedation during FOI are reviewed.