Remimazolam tosilate in upper gastrointestinal endoscopy: A multicenter, randomized, non-inferiority, phase III trial

Safety and effectiveness of the combination of remimazolam tosilate and propofol in gastroscopy: a multicenter, randomized controlled, single-blind clinical trial

Remimazolam tosilate (RT) is a new short-acting γ-aminobutyric acid A (GABAA) receptors agonist. However, its optimal use mode and dosage still remain unclear. This study aimed to examine the safety and effectiveness of the combination of RT and propofol in gastroscopy. This was a prospective, single-blind, randomized, multicenter, parallel-group study. All eligible 256 patients were randomized into the following 3 groups. Patients were anesthetized with propofol (Group P), RT (Group R) or the combination of RT and propofol (Group RP). The primary efficacy endpoints were: body movement score; satisfaction of gastroscopy doctors; success rate of sedation and effects on sleep status. Sedation induction time, time to be fully alert and adverse events were also recorded. The probability of complete immobility was lower in group R (33.73%) than in group P (86.67%) and RP (83.13%). The rate of doctors' satisfaction was much lower in group R (28.92%) than in group P (77.78%) and RP (72.29%). The success rate of sedation and sleep outcome score has no difference in the three groups. The time to adequate sedation was longer in group RP (77.27 ± 18.63 s) than in group P (64.47 ± 24.36 s), but much shorter than that in group R (102.84 ± 46.43s). The time to be fully alert was shorter in group R (6.30 ± 1.52 min) and RP (6.54 ± 1.13 min) than in group P (7.87 ± 1.08 min). The proportion of sedative hypotension was significantly higher in group P (41.11%) than in group R (1.20%) and group RP (3.61%) (p < 0.001). The incidence of respiratory depression was much higher in group P (17.78%) than in group R (no patient) and group RP (1.2%). The incidence of adverse events was lower in groups R (4.82%) and RP (9.64%) than in group P (31.11%). The combination of RT and propofol takes effect quickly, makes patients alert quickly, provides a sufficient depth of sedation, reduces body movement, does not inhibit circulation and respiratory function, does not affect sleep, and is the preferred mode for gastroscopy doctors and anesthesiologists.

Determination of the 95% effective dose of remimazolam tosylate in anesthesia induction inhibits endotracheal intubation response in senile patients

Background and Purpose: The prevalence of elderly patients prompts anesthesiologists to determine the optimal dose of medication due to the altered pharmacokinetics and pharmacodynamics of this population. The present study aimed to determine the 95% effective dose (ED₉₅) of remimazolam tosylate in anesthesia induction to inhibit endotracheal intubation-related cardiovascular reaction in frail and non-frail senile patients. Methods: A prospective sequential allocation dose-finding study of remimazolam tosylate was conducted on 80 elderly patients who received general anesthesia between May and June 2022 at the First Affiliated Hospital of Nanchang University. The initial dose was 0.3 mg/kg. The blood pressure and heart rate fluctuations during intubation were either <20% (negative cardiovascular response) or ≥20% (positive cardiovascular response). If positive, the dose of the next patient was increased by 0.02 mg/kg, while if negative, it was reduced by 0.02 mg/kg according to the 95:5 biased coin design (BCD). The ED₉₅ and 95% confidence intervals (CIs) were determined using R-Foundation isotonic regression and bootstrapping methods. Results: The ED₉₅ of remimazolam tosylate to inhibit the response during tracheal intubation was 0.297 mg/kg (95% CI: 0.231-0.451 mg/kg) and 0.331 mg/kg (95% CI: 0.272-0.472 mg/kg) in frail and non-frail senile patients, respectively. Conculation and Implications: The CI of the two groups overlap, and no difference was detected in the ED₉₅ of remimazolam tosylate in inhibiting endotracheal intubation-related cardiovascular response in frail and non-frail senile patients. These results suggested that remimazolam tosylate is an optimal anesthesia inducer for all elderly patients. Clinical Trial Registration: https://www.chictr.org.cn, identifier ChiCTR2200055709.

Efficacy and safety of remimazolam tosilate versus propofol in patients undergoing day surgery: a prospective randomized controlled trial

BACKGROUND

Remimazolam tosilate (RT) is a novel short-acting GABA (A) receptor agonist that has a rapid recovery from procedural sedation and can be fully reversed by flumazenil. To date, there have been relatively few articles comparing RT and propofol for general anesthesia. This study aimed to assess the efficacy and safety of RT with or without flumazenil compared with propofol in general anesthesia for day surgery.

METHODS

115 patients scheduled for day surgery were randomized into three groups: RT (n = 39), RT + flumazenil (n = 38) and propofol (n = 38). The primary endpoints were anesthesia induction time and time until fully alert. Anesthesia success rate, bispectral index (BIS) values, injection pain, opioid and vasopressor dosages, postoperative recovery profiles and perioperative inflammatory and cognitive changes were assessed. Any adverse events were recorded.

RESULTS

Induction times were similar among the three groups (P = 0.437), but the median time until fully alert in patients treated with RT was longer than that of the propofol or RT + flumazenil groups (17.6 min vs. 12.3 min vs. 12.3 min, P < 0.001). The three groups had comparable postoperative recovery quality and inflammatory and cognitive state changes (P > 0.05). Smaller percentages of patients who received RT (26.3%) and RT + flumazenil (31.6%) developed hypotension during anesthesia maintenance compared with propofol (68.4%), and consequently less ephedrine (P < 0.001) and phenylephrine (P = 0.015) were needed in the RT group. Furthermore, serum triglyceride levels were lower (P < 0.001) and injection pain was much less frequent in the RT with or without flumazenil groups compared with the propofol group (5.3% vs. 0% vs. 18.4%).

CONCLUSION

RT permits rapid induction and comparable recovery profile compared with propofol in general anesthesia for day surgery, but has a prolonged recovery time without flumazenil. The safety profile of RT was superior to propofol in terms of hypotension and injection pain.

TRIAL REGISTRATION

The study was registered at Chinese Clinical Trial Registry http://www.chictr.org.cn/ (Registration date: 19/7/2021; Trial ID: ChiCTR2100048904).

Study Protocol of a Multicenter, Randomized, Single-Blind Trial: Efficacy and Safety of Remimazolam Tosylate for Sedation in ICU Patients

INTRODUCTION

Pharmacodynamic and pharmacokinetic studies in animal experiments and a phase 1 study suggested remimazolam tosylate as an effective and safe sedation/anesthetic agent. However, the effects and safety dose of remimazolam for light sedation in intensive care unit (ICU) patients are not clear and should be confirmed in a phase 2 study.

METHODS

Sixty ICU patients requiring sedation treatment and undergoing mechanical ventilation will be enrolled and randomly assigned to a high dose group (HD group, 30 cases) and a low dose group (LD group, 30 cases) in a 1:1 ratio. Patients in both groups will be sedated using remimazolam tosylate in a primary dose of 0.08 mg/kg and a range of 0-2.0 mg/kg/h after randomization. Dose adjustment will be made at the range of every 0.1 mg/kg/h in the LD group and 0.2 mg/kg/h in the HD group to maintain the target Richmond Agitation and Sedation Score (RASS) at - 2 to + 1. The primary outcome will be the proportion of subjects that meet the following conditions: the time within the range of RASS (- 2 to + 1) accounts for 70% of the study drug administration time; without other rescue treatments. Secondary outcomes including the percentage time to reach the sedation goal; the proportion of subjects receiving rescue sedation and/or analgesic, and the mean dose of rescue drug throughout the study period; duration of mechanical ventilation; recovery time to full consciousness and nursing scores. Evaluations of safety including adverse events (AEs), serious AEs, physical examination, laboratory examination, etc. OUTCOME: The results of this study will provide crucial information for the use of remimazolam tosylate for ICU sedation.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT05152303.

Efficacy of continuous intravenous remimazolam versus midazolam in the extraction of impacted wisdom teeth: protocol of a randomised controlled trial

INTRODUCTION

Benzodiazepines such as midazolam are widely used to moderately sedate patients during impacted wisdom tooth extraction to reduce anxiety in outpatient surgery. This present protocol was designed to determine whether continuous intravenous remimazolam, a new ultrashort-acting benzodiazepine, produces superior postoperative recovery quality to that of midazolam in patients undergoing extraction of impacted wisdom teeth.

METHODS AND ANALYSIS

This study is a multicentre randomised controlled trial conducted at Peking Union Medical College Hospital, Beijing Anzhen Hospital and Beijing Shijitan Hospital in China. Approximately 150 participants undergoing extraction of impacted mandibular wisdom teeth will be randomly allocated to two groups (remimazolam and midazolam). The participants will be administered standard interventions to ensure they achieve a sedation level of III on the Ramsay sedation scale during the treatment. Preoperative and anaesthesia management and surgical techniques will be standardised for all participants. The primary outcome is recovery time for complete alertness and the secondary outcomes are anterograde amnesia during and after surgery, and interruption during operation for poor compliance or safety concerns.

ETHICS AND DISSEMINATION

This study has been approved by the Ethics Review Committee of Peking Union Medical College Hospital (approval number: ZS-3142), Beijing Anzhen Hospital (approval number: KS2022082) and Beijing Shijitan Hospital (approval number: 2023-4).

TRIAL REGISTRATION NUMBER

NCT05350085.

Perioperative management and drug selection for sedated/anesthetized patients undergoing MRI examination: A review

In recent years, magnetic resonance imaging (MRI) technology has become an indispensable imaging tool owing to significant improvements in MRI that have opened up new diagnostic perspectives. Due to the closed environment, long imaging time, and need to remain still during the examination process, the examiner may cannot cooperate with the completion of the examination of the procedure, which increases the need for deep sedation or anesthesia. Achieving this can sometimes be challenging, especially in the special nontraditional environment of MRI equipment (unfamiliar and narrow spaces, away from patients, strong magnetic fields) and in special populations requiring sedation/anesthesia during examinations, which pose certain challenges for the perioperative anesthesia management of MRI. A simple "checklist" is necessary because it allows the anesthesiologist to become familiar with the particular environment and human and material resources as quickly as possible. For the choice of sedative/anesthetic, the traditional drugs, such as midazolam and ketamine, are still used due to the ease of administration despite their low sedation success rate, prolonged recovery, and significant adverse events. Currently, dexmedetomidine, with respiratory drive preservation, propofol, with high effectiveness and rapid recovery, and sevoflurane, which is mild and nonirritating, are preferred for sedation/anesthesia in children and adults undergoing MRI. Therefore, familiarity with the perioperative management of patient sedation and general anesthesia and drug selection in the MRI environment is critical for successful surgical completion and for the safe and rapid discharge of MRI patients receiving sedation/anesthesia.

Remimazolam Compared to Propofol During Hysteroscopy: A Safety and Efficacy Analysis

INTRODUCTION

Propofol is the main drug used to induce sedation for endoscopic procedures, and few drugs had shaken its dominant clinical use for a decade until the development of remimazolam. Remimazolam has been demonstrated to perform well in post-marketing studies on sedation for colonoscopy or other procedures requiring short periods of sedation. This study aimed to establish whether remimazolam was effective and safe for inducing sedation for hysteroscopy.

METHODS

One hundred patients who were scheduled to undergo hysteroscopy were randomly assigned to receive induction with remimazolam or propofol. A dose of 0.25 mg/kg remimazolam was administered. Propofol was started at 2-2.5 mg/kg. Before remimazolam or propofol induction, 1 μg/kg fentanyl was infused. Hemodynamic parameters, vital signs, and bispectral index (BIS) values were measured and adverse events recorded to evaluate safety. We comprehensively evaluated the efficacy and safety of the two drugs by the success rate of induction, fluctuation of vital signs, depth of anesthesia, adverse reactions, recovery time, and other indicators.

RESULTS

Information on 83 patients was successfully recorded and carefully documented. The success rate of sedation in the remimazolam group (group R) was 93%, which was lower than for the propofol group (group P) (100%), but there was no statistically significant difference between the two groups. The incidence of adverse reactions in group R (7.5%) was significantly lower than that in group P (67.4%), and the results were statistically significant (P < 0.01). The fluctuation of vital signs in group P was more severe after induction, especially in patients with cardiovascular diseases.

CONCLUSIONS

Remimazolam avoids the injection pain produced by propofol sedation, has a better pre-sedation experience, had the advantage of stable hemodynamics after injection compared to propofol, and a lower respiratory depression rate in the study patients.

The safety and efficacy of remimazolam tosylate for induction and maintenance of general anesthesia in pediatric patients undergoing elective surgery: Study protocol for a multicenter, randomized, single-blind, positive-controlled clinical trial

Introduction: Remimazolam is an ultra-short-acting benzodiazepine sedative agent commonly used in general anesthesia, procedural sedation, and intensive care unit (ICU) sedation. This study aimed to explore the efficacy and safety of remimazolam versus propofol for the induction and maintenance of general anesthesia in preschool-age children undergoing elective surgery. Methods and analysis: In this multicenter, randomized, single-blind, positive-controlled non-inferior clinical trial, one hundred ninety-two children aged 3-6 years will be randomly allocated as a 3:1 ratio into two groups: Group R with an intravenous dose of remimazolam 0.3 mg/kg for the induction of anesthesia followed by a constant infusion rate of remimazolam 1-3 mg/kg/h to maintain anesthesia, and Group P with an intravenous dose of propofol 2.5 mg/kg for the induction of anesthesia followed by a constant infusion rate of propofol 4-12 mg/kg/h to maintain anesthesia. The primary outcome will be the rate of the successful induction and maintenance of anesthesia. The secondary outcomes will include the time to LoC, the Bispectral Index (BIS) value, awakening time, extubation time, post-anesthesia care unit (PACU) discharge time, usage of additional sedative drugs during the induction period, usage of remedial drugs in PACU, emergence delirium, pain in PACU, behavior scores at day 3 after surgery, parental and anesthesiologists' satisfaction, and adverse events. Ethics and dissemination: This study has been approved by the ethics review boards at all participating hospitals. The Ethics Committee of the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University (Reference No. LCKY 2020-380, November 13, 2020) is the central ethics committee.

Comparison of Remimazolam Tosilate and Etomidate on Hemodynamics in Cardiac Surgery: A Randomised Controlled Trial

Background

Remimazolam tosilate (RT) is a new ultrashort-acting γ-aminobutyric acid subtype A (GABA_A) agonist, with the characteristics of rapid onset and offset, minimal cardiorespiratory depression. Currently, few studies have compared the effect of RT and etomidate on hemodynamics during anesthesia induction. Here, we aimed to compare the hemodynamic effects of different doses of RT and etomidate for anesthesia induction in patients undergoing cardiac surgeries.

Methods

Patients were recruited from January to September 2022 in this single-center, prospective, randomized, double-blind trial. A total of 117 patients undergoing selective valve replacement surgery were randomly divided into low-dose RT (0.2 mg/kg) group (group LR), high-dose RT (0.3 mg/kg) group (group HR), or etomidate (1.5 mg/kg) group (group E), respectively. The primary outcome was hemodynamic fluctuations (mean arterial pressure fluctuation value [∆MAP]; heart rate fluctuation value [∆HR]) during anesthesia induction. Secondary outcomes included the incidence of adverse drug reactions (injection pain and myoclonus) and adverse cardiovascular events, vital signs at different time points and the cumulative doses of vasoactive drugs.

Results

The hemodynamic fluctuations (∆MAP) in group LR and group E were significantly lower than that in group HR. In addition, the incidence of hypotension and the cumulative norepinephrine doses in group E and group LR were also significantly lower than that in group HR. Furthermore, the incidence of injection pain and myoclonus in group LR and group HR were less frequently recorded compared with group E. There were no significant differences in terms of ∆HR, tachycardia, hypertension, severe bradycardia, vital signs at different time points, lactic acid and blood glucose between both groups.

Conclusion

Compared with etomidate, low-dose RT (0.2mg/kg) can not only provide stable hemodynamic parameters but also cause fewer adverse reactions when used for anesthesia induction in patients with cardiac disease.

Remimazolam as the Primary Agent for Sedation During Cardiac Catheterization in Three Patients With Comorbid Cardiac Conduction Abnormalities

General anesthesia or procedural sedation may be required to ensure immobility, facilitate completion of the procedure, and ensure patient comfort during diagnostic or therapeutic procedures in the cardiac catheterization suite. Although propofol and dexmedetomidine are two of the more commonly chosen agents, concerns regarding their impact on inotropic, chronotropic or dromotropic function may limit their applicability based on underlying patient comorbid conditions. We present three patients with comorbid conditions involving pacemaker (natural or implanted) function or cardiac conduction which impacted the choice of agent for procedural sedation during procedures in the cardiac catheterization suite. Remimazolam, a novel ester-metabolized benzodiazepine, was used as the primary agent for sedation in an effort to limit detrimental effects on chronotropic and dromotropic function which may be seen with propofol or dexmedetomidine. Remimazolam's potential utility in procedural sedation is discussed, previous reports of its use are reviewed, and dosing algorithms are presented.

Effect of remimazolam tosilate on the incidence of hypoxemia in elderly patients undergoing gastrointestinal endoscopy: A bi-center, prospective, randomized controlled study

Background: Remimazolam tosilate is a new ultra-short-acting benzodiazepine sedative medicine. In this study, we evaluated the effect of remimazolam tosilate on the incidence of hypoxemia during sedation in elderly patients undergoing gastrointestinal endoscopy. Methods: Patients in the remimazolam group received an initial dose of 0.1 mg/kg and a bolus dose of 2.5 mg of remimazolam tosilate, whereas patients in the propofol group received an initial dose of 1.5 mg/kg and a bolus dose of 0.5 mg/kg of propofol. Patients received ASA standard monitoring (heart-rate, non-invasive blood pressure, and pulse oxygen saturation) during the entire examination process. The primary outcome was the incidence of moderate hypoxemia (defined as 85%≤ SpO₂< 90%, >15s) during the gastrointestinal endoscopy. The secondary outcomes included the incidence of mild hypoxemia (defined as SpO₂ 90%-94%) and severe hypoxemia (defined as SpO₂< 85%, >15s), the lowest pulse oxygen saturation, airway maneuvers used to correct hypoxemia, patient's hemodynamic as well as other adverse events. Results: 107 elderly patients (67.6 ± 5.7 years old) in the remimazolam group and 109 elderly patients (67.5 ± 4.9 years old) in the propofol group were analyzed. The incidence of moderate hypoxemia was 2.8% in the remimazolam group and 17.4% in the propofol group (relative risk [RR] = 0.161; 95% confidence interval [CI], 0.049 to 0.528; p < 0.001). The frequency of mild hypoxemia was less in the remimazolam group, but not statistically significant (9.3% vs. 14.7%; RR = 0.637; 95% CI, 0.303 to 1.339; p = 0.228). There was no significant difference in the incidence of severe hypoxemia between the two groups (4.7% vs. 5.5%; RR = 0.849; 95% CI, 0.267 to 2.698; p = 0.781). The median lowest SpO₂ during the examination was 98% (IQR, 96.0%-99.0%) in patients in the remimazolam group, which was significantly higher than in patients in the propofol group (96%, IQR, 92.0%-99.0%, p < 0.001). Patients in the remimazolam group received more drug supplementation during endoscopy than patients in the propofol group (p = 0.014). There was a statistically significant difference in the incidence of hypotension between the two groups (2.8% vs. 12.8%; RR = 0.218; 95% CI, 0.065 to 0.738; p = 0.006). No significant differences were found in the incidence of adverse events such as nausea and vomiting, dizziness, and prolonged sedation. Conclusion: This study explored the safety of remimazolam compared with propofol during gastrointestinal endoscopy in elderly patients. Despite the increased supplemental doses during sedation, remimazolam improved risk of moderate hypoxemia (i.e., 85%≤ SpO₂ < 90%) and hypotension in elderly patients.

The difference in mean arterial pressure induced by remimazolam compared to etomidate in the presence of fentanyl at tracheal intubation: A randomized controlled trial

Background: Combined use of hypnotic and opioids during anesthesia inductions decreases blood pressure. Post-induction hypotension (PIHO) is the most common side effect of anesthesia induction. We aimed to compare the difference in mean arterial pressure (MAP) induced by remimazolam with that induced by etomidate in the presence of fentanyl at tracheal intubation. Methods: We assessed 138 adult patients with American Society of Anesthesiologists physical status I-II who underwent elective urological surgery. Patients were randomly allocated to receive either remimazolam or etomidate as alterative hypnotic in the presence of fentanyl during anesthesia induction. Comparable BIS values were achieved in both groups. The primary outcome was the difference in the MAP at tracheal intubation. The secondary outcomes included the characteristics of anesthesia, surgery, and adverse effects. Results: The MAP was higher in the etomidate group than in the remimazolam group at tracheal intubation (108 [22] mmHg vs. 83 [16] mmHg; mean difference, -26; 95% confidence interval [CI], -33 to -19; p < 0.0001). Heart rate was significantly higher in the etomidate group than in the remimazolam group at tracheal intubation. The patients' condition warranted the administration of ephedrine more frequently in the remimazolam group (22%) than in the etomidate group (5%) (p = 0.0042) during anesthesia induction. The remimazolam group had a lower incidence of hypertension (0% vs. 9%, p = 0.0133), myoclonus (0% vs. 47%, p < 0.001), and tachycardia (16% vs. 35%, p = 0.0148), and a higher incidence of PIHO (42% vs. 5%, p = 0.001) than the etomidate group during anesthesia induction. Conclusion: Remimazolam was associated with lower MAP and lower heart rate compared to etomidate in the presence of fentanyl at tracheal intubation. Patients in the remimazolam group had a higher incidence of PIHO, and their condition warranted the administration of ephedrine more frequently than in the etomidate group during anesthesia induction.

Effects of opioid-free propofol or remimazolam balanced anesthesia on hypoxemia incidence in patients with obesity during gastrointestinal endoscopy: A prospective, randomized clinical trial

There are presently no consensuses on the optimal sedation strategy for obese patients during gastrointestinal endoscopy. This study aim to explore the effects of opioid-free propofol or remimazolam balanced anesthesia on hypoxemia incidence in patients with obesity. A total of 264 patients were randomized to remimazolam + esketamine group (group R) or propofol + esketamine group (group P). Anesthesia in group P was administrated by propofol, esketamine and in group R by remimazolam, esketamine. The primary outcome was incidence of hypoxemia. Secondary outcomes were the time to loss of consciousness (LoC) and to recovery and the incidence of intraoperative and postoperative adverse reactions. We found the incidence of mild hypoxemia in group R was similar to that in group P (14.2% vs. 11.5%, p = 0.396). The incidence of severe hypoxemia in group R was significantly lower than Group P (4.2% vs. 9.2%, p = 0.019). The time to LoC in group R was longer than group P [Median (interquartile range, IQR): 53 s (45 to 61) vs. 50 s (42 to 54), p = 0.001]. The time to recovery from anesthesia in group R was less than group P [Median (IQR): 48 min (41 to 58) vs. 55.5 min (46 to 67), p<0.001]. There was no significant difference in the incidence of adverse events (p > 0.05 for all). We concluded that compared with propofol combined with esketamine, remimazolam combined with esketamine can reduce the incidence of severe hypoxemia during gastrointestinal endoscopy in obese patients. Clinical Trial Registration: www.chictr.org.cn, Identifier: ChiCTR2200065575.

Efficacy and safety of remimazolam-based sedation for intensive care unit patients undergoing upper gastrointestinal endoscopy: a cohort study

BACKGROUND

Remimazolam is a novel ultra-short-acting sedative, but its safety and adverse events (AEs) in high-risk patients in the intensive care unit (ICU) setting remain unknown.

METHODS

This was a single-center, retrospective study that compared remimazolam to propofol and midazolam in patients undergoing upper gastrointestinal endoscopy. The primary outcome was the incidence of treatment-related AEs. The secondary outcomes were the time to extubation, the length of ICU stay, and the average cost of sedative per case.

RESULTS

Of the 88 patients analyzed, 47 were treated with remimazolam (mean dose, 7.90±4.84 mg), and 41 were treated with propofol (21.19±17.98 mg) or midazolam (3.08±2.17 mg). There was no statistically significant difference in the average duration of the endoscopic procedure (35.89±13.37 min vs. 44.51±21.68 min, P=0.133) or the time to extubation (15.00±9.75 h vs. 20.59±18.71 h, P=0.211) in the remimazolam group (group I) compared to the propofol or midazolam group (group II). ICU stays (5.40±2.93 d vs. 4.63±3.31 d, P=0.072) and treatment-related AEs (48.61% vs. 51.38%, P=0.056) were similar between groups. The average cost of sedative per case was significantly lower in the group I than in the group II (RMB 16.07±10.58 yuan vs. RMB 24.37±15.46 yuan, P=0.016).

CONCLUSION

Remimazolam-based sedation was noninferior to the classic sedatives and had lower average cost per case, indicating that it may be used as a promising sedative for high-risk patients during endoscopic procedures in the ICU setting.

Efficacy and safety of remimazolam tosylate for sedation during upper gastrointestinal endoscopy: study protocol for a multicenter randomized controlled trial

BACKGROUND

Gastrointestinal endoscopy has been associated with difficult experiences and can leave patients with an unpleasant impression. Propofol and midazolam are the most commonly used intravenous anesthetics for sedation during gastrointestinal endoscopy. However, cardiac and pulmonary adverse events are the primary concerns associated with the use of these sedatives. Remimazolam tosylate is an ultra-short-acting benzodiazepine drug with a mild inhibitory effect on the respiratory and circulatory systems. These properties qualify remimazolam tosylate to be used as a replacement for propofol or midazolam as a sedative during gastrointestinal endoscopy. This study aims to describe the efficacy and safety of remimazolam tosylate as a sedative for upper gastrointestinal endoscopy.

METHODS

A multicenter, randomized, single-blind, parallel-controlled, noninferiority clinical study will be conducted to evaluate the efficacy and safety of remimazolam tosylate as a sedative during upper gastrointestinal endoscopy. Participants (n = 1800) will be randomized to receive remimazolam tosylate at 0.15 mg/kg (experimental group 1), remimazolam tosylate at 0.2 mg/kg (experimental group 2), or propofol at 1.5 mg/kg (control group). Procedure success will be assessed and defined as the completion of upper gastrointestinal endoscopy without the administration of a rescue sedative agent or more than two top-up doses of the trial drug in any 5-min period after initial administration. Sedation quality will be evaluated using the Modified Observer's Assessment of Alertness/Sedation score. Adverse events will be recorded to evaluate safety.

DISCUSSION

This study will determine the optimal dosage of remimazolam tosylate during upper gastrointestinal endoscopy and will describe its efficacy and safety. These findings may contribute to a more comfortable and safer experience for patients compared with that when the conventional sedative propofol is used.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04727034. Registered on February 18, 2021.

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

Background

Remimazolam tosilate (RT) is a new type of γ-aminobutyric acid subtype A (GABA_A) receptor agonist, having the possibility to be an ideal sedative drug for procedural sedation. At present, there are few studies on the effect of RT on respiratory depression in elderly patients. We aimed to evaluate the effect of RT on respiratory depression in elderly patients undergoing gastroscopy.

Methods

This prospective, randomized, single-blinded trial recruited patients from eight centers in China between May 2022 and July 2022. A total of 346 elderly patients undergoing gastroscopy were randomly divided into RT group (0.2 mg/kg) or propofol group (1.5 mg/kg), respectively. The primary outcome was the incidence of respiratory depression. Secondary outcomes include the incidence of sedative-related adverse events, the success rate of sedation, time to fully alert, time to loss of consciousness (LOC), time to ready for discharge, as well as the the patients, endoscopists and anethetists' satisfaction.

Results

The incidence of respiratory depression was significantly reduced in the RT group compared with the propofol group (9.8% vs 17.9%, P=0.042). The time of LOC and fully alert in the RT group were longer than that in the propofol group (P < 0.05). The incidences of hypotention (50.9% vs 32.4%, P=0.001) and hypotension requiring treatment (5.8% vs 1.7%, P=0.031) were significantly higher in the propofol group than that in the RT group. The incidence and severity of injection pain were more frequently recorded in the propofol group than that in the RT group (40.5% vs 12.1%, P<0.05). There were no statistically significant differences between the two groups in terms of sedation success rates, time to ready for discharge, endoscopists and anethetists' satisfaction and other sedative-related adverse events.

Conclusion

RT may be a suitable alternative sedative agent for elderly patients undergoing gastroscopy due to its safety profile.

Sedation efficacy of different dose of remimazolam with sufentanil for nerve block in young and elderly patients: a randomized, controlled study

Purpose

Anxiety and pain commonly occur during nerve block, we aimed to investigate the sedation efficacy of different doses of remimazolam with sufentanil in young and elderly patients.

Methods

In this randomized trial, patients aged 18–85 years who underwent nerve block was enrolled. All patients received sufentanil 0.08 μg/kg for analgesia. Young patients (age < 65 years) were randomized into the control group (Group C, 0.9% saline), medium-dose remimazolam (Group M, 0.06 mg/kg) and high-dose remimazolam group (Group H, 0.08 mg/kg). Elderly patients (age ≥ 65 years) were randomized into the Group C, low-dose remimazolam group (Group L, 0.04 mg/kg) and Group M. Primary outcome was the success rate of procedure sedation. Respiratory depression and hypoxia were the interested safety outcomes.

Results

Ninety young and 114 elderly patients were enrolled, respectively. In comparison with Groups C and M, young patients in Group H had the highest success rate of procedure sedation (80.0 vs. 73.3 vs. 43.3%, P = 0.006). Elderly patients in Groups M and L had similar success rates of procedure sedation, which were significantly higher than that in Group C (78.9 vs. 78.9 vs. 50.0%, P = 0.007). In elderly patients, the incidence of respiratory depression and hypoxia tended to be higher in Group M than those in Groups L and C (both P < 0.001).

Conclusion

Remimazolam 0.08 mg/kg provided the best sedation efficacy in young patients while remimazolam 0.04 mg/kg with the trend of less respiratory adverse events was more optimal for elderly patients.

Trial registration

http://www.chictr.org.cn/showproj.aspx?proj=122016.

The 50% and 95% effective doses of remimazolam tosilate with adjuvant sufentanil for sedation in patients with liver cirrhosis undergoing oesophagogastric varices screening endoscopy

WHAT IS ALREADY KNOWN AND OBJECTIVE

Sedation is routinely provided for patients undergoing gastrointestinal endoscopy. Remimazolam tosilate is a novel and short-acting sedative agent that has been used for sedation during endoscopic procedures. The optimal dose of remimazolam in gastrointestinal endoscopy for patients with liver cirrhosis has not been elucidated.

BACKGROUND

To determine the effective dose of remimazolam tosilate with adjuvant sufentanil for sedation in patients with liver cirrhosis undergoing oesophagogastric varices screening endoscopy.

MATERIAL AND METHODS

Patients aged 18-65 years with liver cirrhosis undergoing screening endoscopy for oesophagogastric varices were recruited. Sufentanil 0.15 μg/kg was given intravenously at 2 min before administration of remimazolam tosilate. The initial dose of remimazolam was 0.1 mg/kg and adjusted by 0.025 mg/kg as a step size, based on the Dixon and Massay up-and-down sequential method. Inclusion of patients was stopped after eight crossovers and the calculated median effective dose (ED₅₀ ) of remimazolam for successful endoscopy was obtained by calculating the mean of midpoint of all crossovers. Furthermore, a probit regression was applied to establish the dose-response curve of remimazolam and further assess the 95% effective dose (ED₉₅ ) of remimazolam.

RESULTS

The calculated ED₅₀ of remimazolam for successful endoscopy using the mean of midpoint of all crossovers was 0.097 mg/kg (95% CI, 0.004-0.099 mg/kg). Using the probit regression analysis, the ED₅₀ and ED₉₅ of remimazolam for successful endoscopy was 0.097 mg/kg (95% CI, 0.004-0.099 mg/kg) and 0.107 mg/kg (95% CI, 0.103-0.336 mg/kg), respectively. No adverse events were observed throughout the study period.

CONCLUSIONS

This pilot study suggests that the ED₅₀ and ED₉₅ of remimazolam tosilate with adjuvant sufentanil for sedation in liver cirrhosis patients undergoing oesophagogastric varices screening endoscopy was 0.097 and 0.107 mg/kg, respectively.

Remimazolam versus propofol for deep sedation/anaesthesia in upper gastrointestinal endoscopy in elderly patients: A multicenter, randomized controlled trial

BACKGROUND AND OBJECTIVE

Propofol is the most commonly used sedative in gastrointestinal endoscopic procedures, but is associated with cardiorespiratory suppression, particularly in elderly patients. Remimazolam is a new short-acting GABA(A) receptor agonist with minimal impact on cardiorespiratory suppression, and may be a viable alternative in elderly patients undergoing endoscopic procedures.

METHODS

This multicenter, randomized controlled trial was conducted between September 2020 and September 2021. Elderly patients (65-85 years of age) scheduled to undergo upper gastrointestinal endoscopy were randomized in 1:1 ratio to receive remimazolam tosilate (300 mg/h) or propofol (3 g/h) in addition to 50-μg fentanyl, until the Modified Observer's Assessment of Alertness/Sedation Scale (MOAA/S) reached ≤1. MOAA/S was maintained at 0 or 1 throughout the procedure using 2.5 mg remimazolam or 0.5 mg/kg propofol boluses in the two groups, respectively. The primary outcome was the rate of hypotension (defined as systolic blood pressure at ≤90 mmHg or > 30% decline vs. the baseline). Bradycardia was defined as heart rate ≤50 per minute; respiratory depression was defined as respiratory rate <8 per minute and/or SpO₂  < 90%.

RESULTS

A total of 400 patients (161 men and 239 women; 70.4 ± 4.6 years of age) were enrolled (200 patients per group). Average body mass index was 22.2 ± 2.4 kg/m² . The rate of hypotension was 36.5% in the remimazolam group and 69.6% in the propofol group (p < 0.001). The remimazolam group also had a lower rate of bradycardia (1.5% vs. 8.5%, p < 0.001), respiratory depression (4.5% vs. 10.0%, p < 0.05) and pain at the injection site (0% vs. 12.0%, p < 0.001).

CONCLUSION

Remimazolam was associated with a lower rate of hypotension in elderly patients undergoing upper gastrointestinal endoscopy under deep sedation/anaesthesia than propofol.

Remimazolam: An Updated Review of a New Sedative and Anaesthetic

Remimazolam (CNS7056) is a novel benzodiazepine for intravenous sedation; it has an ultra-short duration of action and was recently approved for use in procedural sedation and general anaesthesia. It acts on γ-aminobutyric acid type A receptors and is rapidly converted into an inactive metabolite by tissue esterase enzymes. Remimazolam has been successfully used in endoscopic inspection or surgery and general anaesthesia induction and maintenance with fast and predictable onset and recovery times, high procedure success rates, and minor respiratory and hemodynamic fluctuations and without serious drug-related adverse reactions. If needed, the effects of remimazolam can be reversed by flumazenil, which allows prompt termination of sedation. Although remimazolam has great potential for sedation in patients admitted to intensive care units, future studies are needed to evaluate its efficacy and safety in patients requiring sedation for a long period, and numerous studies are warranted to explore the optimal dose in different application scenarios. The review aimed to provide an introduction to the process of remimazolam synthesis and its current clinical uses and future clinical developments.

The effective doses of remimazolam besylate in the procedural sedation of endoscopic retrograde cholangiopancreatography

This study aimed to determine the values of the half-effective dose (ED50) and 95% effective dose (ED95) of remimazolam besylate used in the procedural sedation of endoscopic retrograde cholangiopancreatography (ERCP). Sixty patients who fulfilled the inclusion and exclusion criteria of this study were selected. Sufentanil was administered intravenously and remimazolam besylate was administered 2 min later. ERCP treatment was feasible when the modified alertness/sedation (MOAA/S) score was ≤2. If choking or movement occurred during duodenoscope placement, it was considered as a positive reaction. The dose was increased in the next patient; otherwise, it was considered as a negative reaction, and the dose was reduced in the next patient. The ED50 and ED95 values and 95% confidence interval (CI) of remimazolam besylate were calculated by Probit regression analysis. All 60 patients completed the trial. The ED50 and ED95 values of remimazolam besylate were 0.196 and 0.239 mg/kg, respectively, for the procedural sedation of ERCP. The time of MOAA/S score ≤ 2 was (82.58 ± 21.70) s, and the mean time of awakening was (9.03 ± 5.64) min. Transient hypotension was observed in two patients without medical intervention. The ED50 and ED95 values of remimazolam besylate used in the procedural sedation of ERCP were 0.196 and 0.239 mg/kg, and the dose of the medications has definite efficacy and good safety.

First dose-ranging study of remimazolam in Japanese patients undergoing gastrointestinal endoscopy: Phase II investigator-initiated clinical trial

OBJECTIVES

Remimazolam, an ultra-short-acting benzodiazepine, has been used for procedural sedation in the United States. We conducted an investigator-initiated clinical trial to determine the appropriate dose of remimazolam required for sedation during gastrointestinal endoscopy in Japanese subjects.

METHODS

In this single-center, open-label, uncontrolled, phase II trial, a three-stage cohort investigated the appropriate initial and additional doses of remimazolam required for gastrointestinal endoscopy. This study was designed with advice from the Pharmaceuticals and Medical Devices Agency. The initial and additional doses were 2 mg and 1 mg/dose, 3 mg and 1 mg/dose, and 5 mg and 2 mg/dose in cohorts 1, 2, and 3, respectively. Each cohort included 10 cases of upper gastrointestinal endoscopy and colonoscopy. The primary end-point was the success rate of sedation during gastrointestinal endoscopy.

RESULTS

Sedation was successful in all gastrointestinal endoscopies in cohorts 1 and 2. In cohort 1, sedation was achieved in five (25.0%) and 10 (50.0%) participants with the initial dose and total dose (initial dose + additional dose ≤ the initial dose of the next cohort), respectively, before endoscopy. In cohort 2, sedation was achieved in 11 (55.0%) and 18 (90.0%) participants with the initial dose and total dose, respectively, before endoscopy. No patient in either cohort lost consciousness or required flumazenil or manual ventilation.

CONCLUSION

Initial and additional doses of 3 mg and 1 mg/dose of remimazolam, respectively, were shown to be effective and safe for sedation during gastrointestinal endoscopy in Japanese patients.

Efficacy and Safety of the Remimazolam-Alfentanil Combination for Sedation During Gastroscopy: A Randomized, Double-blind, Single-center Controlled Trial

PURPOSE

Propofol infusion is a popular single drug of choice for sedation in the gastrointestinal endoscopy suite. Drug combinations are more beneficial than single-drug regimens in gastroscopy sedation. However, the cardiopulmonary complications of propofol sedation raise concern. Remimazolam is a novel, ultra-short-acting benzodiazepine sedative, and alfentanil is a weak opioid. During endoscopic procedures, remimazolam is an effective and safe sedative procedure. No synergistic effect has been reported when remimazolam was combined with alfentanil in gastroscopy sedation. Here, we evaluated the effective dose, sedative efficacy, and safety of the remimazolam-alfentanil combination in gastroscopy sedation and compared the results with those of the propofol-alfentanil combination.

METHODS

This study was conducted in two parts. In Part 1, Dixon's up-and-down method (sequential distribution) was adopted for determining the 95% effective dose (ED95) (95% CI) and 95% CI of remimazolam combined with 5 µg/kg alfentanil. In Part 2, after obtaining the predictive remimazolam ED95, 161 patients were randomized into the remimazolam group (remimazolam-alfentanil) and the propofol group (propofol-alfentanil). The effectiveness of the drug combinations was measured according to successful sedation parameters. Changes in vital signs and the appearance of adverse events were used to assess the safety of drug combinations. Evaluation of patient and physician satisfaction was included as quality indicators of treatment.

RESULTS

Baseline demographic and clinical characteristics were comparable between the 2 parts of the study. The ED95 of remimazolam in inhibiting a positive response to gastroscopy placement into the pharyngeal cavity was 0.33 mg/kg (95% CI, 0.289 to 1.023). The procedure success rate was 97.53% in the remimazolam group and 97.50% in the propofol group. The difference in the success rate of the procedure between the remimazolam and propofol groups was 0.03% (95% CI, -2.5 to 2.4). However, the incidence of injection pain, hypotension, respiratory depression, and dizziness was lower in the remimazolam group compared with the propofol group (P < 0.05). Furthermore, patients from the propofol group were more likely to be drowsy, and their work efficiency was reduced the day after leaving the hospital, whereas patients in the remimazolam group were less affected (P < 0.05).

IMPLICATIONS

The ED95 of remimazolam was 0.33 mg/kg when it was combined with alfentanil (5 µg/kg) for gastroscopy sedation. The sedation strategy of remimazolam-alfentanil has noninferior efficacy, fewer adverse effects, and a better postoperative recovery process than propofol-alfentanil for patients undergoing gastroscopy. Chinese Clinical Trials Registry identifier: ChiCTR2100051565.

Profile of Remimazolam in Anesthesiology: A Narrative Review of Clinical Research Progress

Remimazolam is a novel short-acting γ-aminobutyric acid (GABA) receptor agonist with typical characteristics of benzodiazepine sedative drugs, nonorgan-dependent metabolism, long-term infusion without accumulation, and no injection pain. It is quite different from the other current sedative drugs and has broad prospects for application. It has been established that the metabolites of remimazolam are inactive, and the interactions with other drugs are weak with slight cardiopulmonary suppressive effects, showing good effectiveness and safety. During the 2-year period that it has been on the market, remimazolam has been used in multiple clinical scenarios, such as the induction and maintenance of general anesthesia and sedation in outpatient minor procedures or examinations. However, it's use has also prompted widespread concern around the world. Therefore, given its short- and rapid-acting, controllable characteristics remimazolam deserves in-depth study in order for it to be used in fast-track surgery, comfort diagnosis and treatment. Notably, such agents might be of great significance, especially in elderly individuals, patients with critical diseases or patients with liver and kidney insufficiency. The current study reviews recent clinical studies (2015-2022) on remimazolam and summarizes the characteristics of its applications. Specifically, the use of remimazolam in some specific populations are described. This study attempts to provide scientific support for the clinical application of this novel sedative drug in the field of anesthesia.

Efficacy and Safety of Remimazolam Besylate Combined with Alfentanil in Painless Gastroscopy: A Randomized, Single-Blind, Parallel Controlled Study

Background

The efficacy and adverse reactions of remimazolam besylate (RB) in combination with alfentanil in patients with painless gastroscopy remain unclear.

Objective

The aim of the study is to observe the efficacy and adverse reactions of RB in combination with alfentanil in patients with painless gastroscopy RB.

Methods

All patients were randomly divided into two groups: RB combined with the alfentanil group (research group) and propofol combined with the alfentanil group (control group). After full oxygen inhalation and electrocardiographic monitoring, the research group was given 10 μg/Kg alfentanil + RB 0.2 mg/kg intravenously, and the control group was given 10 μg/Kg alfentanil + propofol 1.5 mg/kg. If there is a clinical need, the research group was given 2.5 mg/additional RB, whereas the control group was treated with an additional 0.5 mg/kg propofol. Main outcome measures were as follows: The vital endpoints including diachronic changes in heart rate (HR), blood pressure (BP), respiratory rate (RR), blood oxygen saturation (SPO₂), end-expiratory carbon dioxide (etCO₂), IPI, modified observer's assessment of alert/sedation (MOAA/S), time-related endpoints, perioperative adverse events, endoscopy, and anesthesiologist satisfaction, and 24-hour follow-up of adverse reactions, IPI scores, and satisfaction were recorded.

Results

The HR and BP of the patients in the research group and the control group decreased, with a greater decrease in the control group, and the difference was statistically significant (p < 0.05). The values of RR, PETCO₂, and IPI in the research group and the control group decreased to the lowest at 2-3 min but the decrease in the control group was more significant. Furthermore, there was no significant difference in the time from the completion of administration to 4 minutes of IPI and the total examination time, but the awakening time in the research group was slightly longer than that in the control group, and the difference was statistically significant (p < 0.05). The incidences of respiratory depression and hypotension during the operation were shown to be markedly smaller in the investigation relative to the control team, and the difference was statistically significant (p < 0.05), whereas the occurrence of cough, movements, and singultus was more common in the investigations, and the difference was statistically significant (p < 0.05). The results of the 24-hour follow-up showed that the adverse reactions such as nausea, dizziness, fatigue, abdominal pain, and abdominal distension were much less frequent in the study team, and the difference was statistically significant (p < 0.05), and the patient satisfaction was higher than in the control group, and the difference was statistically significant (p < 0.05). The regression results showed that age, sedative, and total dose of analgesia had significant effects on the results, and the covariance coefficient of sedative was 1.57 of IPI score in the research group higher than that of the control group.

Conclusions

RB combined with alfentanil can provide safe and effective sedation for patients undergoing painless gastroscopy. Compared with propofol, RB and alfentanil for injection can avoid large hemodynamic fluctuations and deep sedation, and have fewer adverse reactions. However, the cases involved in this study are all from a single-center data, which requires further multicenter research and conformation.

New sedatives and analgesic drugs for gastrointestinal endoscopic procedures

Procedural sedation has become increasingly common in endoscopy. Sedatives and analgesics induce anxiolysis and amnesia. In addition, an appropriate level of sedation is necessary for safe procedures including therapeutic endoscopy. Midazolam and propofol are the most commonly used drugs in sedative endoscopy. In recent years, the need to ascertain the safety and effectiveness of sedation has increased in practice. Therefore, new sedatives and analgesic drugs for optimal sedative endoscopy, have recently emerged. This article reviews the characteristics of sedatives and analgesics, and describes their clinical use in gastrointestinal endoscopy.

Sedative effect of remimazolam combined with alfentanil in colonoscopic polypectomy: a prospective, randomized, controlled clinical trial

Background

Remimazolam is a newer benzodiazepine with properties of rapid onset, short duration of action, and fast recovery. Our study was to evaluate the effects of different doses of remimazolam combined with alfentanil in colonoscopic polypectomy.

Methods

One hundred twenty patients were randomly divided into four groups: alfentanil and propofol (AP) group, alfentanil and remimazolam 0.1 mg/kg (AR1 group), 0.15 mg/kg (AR2 group), or 0.2 mg/kg (AR3 group). Patients in the four groups received alfentanil 10 μg/kg, followed by propofol 2 mg/kg and three dosages of remimazolam. Modified Observer's Assessment of Alertness and Sedation (MOAA/S) scale, heart rate (HR), oxygen saturation (SpO₂), respiratory rate (RR), bispectral index (BIS) values and mean arterial pressure (MAP) were collected at intervals of 5 min and analyzed at different time points: before anesthesia (T0), 5 min (T1), 10 min (T2), 15 min after anesthesia (T3) and at the end of surgery (T4). The average MAP was calculated utilizing the average of all MAP values. The primary outcome was the success rate of sedation. Secondary outcomes included time to full alert and adverse events.

Results

The success rate of sedation was 100% among the four groups. The incidence of hypotension was significantly decreased (all P < 0.05) and the average MAP was higher in AR1-AR3 groups than AP group (all P < 0.001). None of the patients developed bradycardia or hypertension during surgery in all study groups. BIS values were higher (all P < 0.001) and the time to full alert was statistically shorter in AR1-AR3 groups (all P < 0.05) compared with the AP group. The MOAA/S score in AR1 was higher than AR2 (P < 0.05) and the AR3 group (P < 0.05) at T1 and BIS values in the AR1 group were significantly higher than AR3 group (P < 0.05) at T4.

Conclusions

Remimazolam combined with alfentanil have a non-inferior sedative effect than propofol during the colonoscopic polypectomy. Moreover, this combination of two short-acting drugs might be a safer alternative.

Trial registration

The clinical trial was registered on (16/05/2021, ChiCTR2100046492).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01805-3.

The hemodynamic stability of remimazolam compared with propofol in patients undergoing endoscopic submucosal dissection: A randomized trial

Objective

Hypotension is common in propofol anesthesia. Whether remimazolam could reduce intraoperative hypotension remains unknown. We therefore tested the primary hypothesis that remimazolam reduces the incidence of intraoperative hypotension compared with propofol in adult patients undergoing endoscopic submucosal dissection (ESD) surgery.

Materials and methods

We conducted a prospective trial to compare patients who received either remimazolam or propofol bolus induction and thereafter intravenous infusion. The hemodynamic parameters were measured using CNAP® Monitor 500 system. Our primary analysis was to compare the incidence of hypotension defined as systolic blood pressure below 90 mmHg between remimazolam and propofol during the whole anesthesia period.

Results

The incidence of hypotension decreased by 50%, from 67.9% in propofol group to 32.1% in remimazolam group (p &lt; 0.01). Patients received less amount of intraoperative phenylephrine in the remimazolam group than the propofol group (0 [0–40] μg vs. 80 [0–200] μg, p &lt; 0.01). Time-weighted average and cumulative time of hypotension was lower in remimazolam group compared with propofol group (p &lt; 0.05). Cardiac output continuously measured by CNAP was preserved much better in remimazolam group compared with propofol group (p = 0.01), while systemic vascular resistance did not differ between the groups. The median time from discontinuation until full alertness was 4 [3–11.8] min in the remimazolam group compared with 15 [12.0–19.8] min in the propofol group (p &lt; 0.01).

Conclusion

Remimazolam has better hemodynamic stability than propofol in adult patients undergoing ESD surgery. The benefits of remimazolam on hemodynamic stability and hypotension prevention may be partly contributed to its better preservation of cardiac output.

Clinical Trial Registration

[http://www.chictr.org.cn/com/25/showproj.aspx?proj=61104], identifier [ChiCTR2000037975].

Efficacy and Safety of Remimazolam Besylate versus Dexmedetomidine for Sedation in Non-Intubated Older Patients with Agitated Delirium After Orthopedic Surgery: A Randomized Controlled Trial

Purpose

The purpose of the present study was to investigate the efficacy and safety of remimazolam besylate compared with dexmedetomidine for the relief of agitated delirium in non-intubated older patients after orthopedic surgery.

Patients and methods

Seventy-five patients were randomly divided into two groups. Patients assigned to the remimazolam group received a loading dose of 0.075 mg/kg remimazolam besylate over 1 minute, followed by a continuous infusion of 0.1 to 0.3 mg/kg/h. Subjects randomized to the dexmedetomidine group received a loading infusion of 0.5 μg/kg dexmedetomidine over 10 minutes, followed by a maintenance dose of 0.2 to 0.7 μg/kg/h. Meanwhile, RASS score-guided dose titration was followed. To assess the efficacy of the study drugs in terms of time to resolution of agitation, time to first achievement of target sedation, percentage of time within the target sedation range, and time to delirium resolution. Safety of the sedatives was evaluated by adverse events during hospitalization.

Results

Time to resolution of agitation did not differ between the two groups. The time to first achievement of target sedation was 19.0 (9.5 to 31.0) minutes for remimazolam besylate vs 43.5 (15.0 to 142.5) minutes for dexmedetomidine (P < 0.001). Percentage of time within the target sedation range was 77.8% for remimazolam besylate-treated patients and 67.4% for dexmedetomidine-treated patients (P = 0.001). Patients in the remimazolam group had longer time to delirium resolution (29.5 [21.3 to 32.5] hours) than those in the dexmedetomidine group (22.8 [18.9 to 28.5] hours) (P = 0.042). Patients sedated with remimazolam besylate had more oversedation (P = 0.036) but less hypotension (P = 0.007).

Conclusion

Compared with dexmedetomidine, remimazolam besylate was equally effective in relieving agitation, and resulted in earlier achievement of sedation goal and more controllable sedation. Remimazolam may be an ideal agent for obtaining rapid tranquillisation.

Anesthesia for digestive tract endoscopy

PURPOSE OF REVIEW

Nonoperating room anesthesia for digestive tract endoscopy has its own specificities and requires practical training. Monitoring devices, anesthetic drugs, understanding of procedures and management of complications are critical aspects.

RECENT FINDINGS

New data are available regarding risk factors for intra- and postoperative complications (based on anesthesia registries), airway management, new anesthetic drugs, techniques of administration and management of advances in interventional endoscopy procedures.

SUMMARY

Digestive tract endoscopy is a common procedure that takes place outside the operating room most of the time and has become more and more complex due to advanced invasive procedures. Prior evaluation of the patient's comorbidities and a good understanding of the objectives and constraints of the endoscopic procedures are required. Assessing the risk of gastric content aspiration is critical for determining appropriate anesthetic protocols. The availability of adequate monitoring (capnographs adapted to spontaneous ventilation, bispectral index), devices for administration of anesthetic/sedative agents (target-controlled infusion) and oxygenation (high flow nasal oxygenation) guarantees the quality of sedation and patient' safety during endoscopic procedures. Knowledge of the specificities of each interventional endoscopic procedure (endoscopic retrograde cholangiopancreatography, submucosal dissection) allows preventing complications during anesthesia.

Total intravenous anesthesia induced and maintained by a combination of remimazolam and remifentanil without a neuromuscular blocking agent: a prospective, observational pilot study

Background

A novel short-acting benzodiazepine, Remimazolam, has recently been approved for general anesthesia and sedation. Hence, we investigated the feasibility and safety of remimazolam during the induction and maintenance of general anesthesia without using a neuromuscular blocking agent (NMBA) in patients undergoing hysteroscopic surgery.

Methods

This prospective observational study included 38 patients undergoing hysteroscopic surgery. Remimazolam and remifentanil were the main anesthetic agents without an NMBA, and a supraglottic airway was inserted to protect the airway. The induction time, amount of each anesthetic agent used during anesthesia, intraoperative bispectral index (BIS) hemodynamic parameters, and recovery profiles were measured.

Results

General anesthesia was successfully administered to 37 patients using remimazolam and remifentanil without NMBA. The induction doses of remimazolam and remifentanil were 0.4 mg/kg (interquartile range [IQR] 0.34–0.47 mg/kg) and 1.07 μg/kg (IQR, 0.90–1.29 μg/kg), respectively. Additionally, the maintenance doses of remimazolam and remifentanil were 1.14 mg/kg/h (IQR, 0.88–1.55 mg/kg/h) and 0.06 μg/kg/min (IQR, 0.04–0.08 μg/kg/min), respectively. Intraoperative BIS values had risen temporarily > 60 in eight patients (21.6%) despite administration of 2 mg/kg/h of remimazolam; thus, they were treated with supplementary midazolam. The median recovery time was 7 min (IQR, 5–8 min) after 40 min (IQR, 40.0–57.5 min) of total mean anesthesia time. There was no correlation between the infusion dose of remimazolam and recovery profiles, such as recovery time, final BIS of anesthesia, modified observer assessment of alertness/sedation (OAA/S) scale or post-anesthesia recovery (PAR) score when arriving at the PACU, and length of stay in the PACU (all P > 0.05).

Conclusion

Remimazolam can be combined with remifentanil without an NMBA in female patients who undergo hysteroscopic surgery, during which a supraglottic airway is a feasible method to protect the airway.

Trial registration

The study protocol was registered at ClinicalTrials.gov (NCT05025410) on 27/08/2021.

Pre-procedural Preparation and Sedation for Gastrointestinal Endoscopy in Patients with Advanced Liver Disease

Gastrointestinal endoscopy in patients with advanced liver disease poses various challenges, a major one being procedural sedation and its associated considerations. While sedation during endoscopy can improve patient comfort, decrease anxiety, and facilitate procedural completion, in patients with advanced liver disease, it is also associated with substantial and unique risks due to alterations in drug metabolism and other factors. As such, the choice of sedative agent(s) and related logistics may require careful inter-disciplinary planning and individualized considerations. Furthermore, a large proportion of agents require dose reductions and particular monitoring of the vital signs, level of consciousness, and other indices. In the present review, we provide a contemporary overview of procedural sedation considerations, commonly used intravenous sedatives, and second-line as well as novel sedatives for gastrointestinal endoscopy in patients with advanced liver disease.

Remimazolam tosilate compared with propofol for gastrointestinal endoscopy in elderly patients: a prospective, randomized and controlled study

Background

Remimazolam tosilate (HR7056, RT), a novel ultrashort-acting benzodiazepine, can be used for procedural sedation and general anaesthesia. However, few studies have focused on the sedative effect of RT during gastrointestinal endoscopy in elderly patients. The purpose of this study is to compare the sedative effect of RT and propofol for gastrointestinal endoscopy in elderly patients.

Methods

A total of 82 patients aged ≥65 years with an American Society of Anaesthesiologists (ASA) grade I-II and a body mass index (BMI) of 18.0 to 30.0 kg/m² who were scheduled for gastrointestinal endoscopy from Jan 2021 to Aug 2021 were selected and randomly divided into a RT group and a propofol group. Alfentanil 5 μg/kg was used for analgesia in both groups. The RT group was given remimazolam tosilate 0.15 mg/kg with supplemental doses of 0.05 mg/kg as need, while the propofol group was given propofol 1.5 mg/kg with supplemental doses of 0.5 mg/kg. The supplemental doses were determined by the modified observational alertness/sedation assessment (MOAA/S) score and the patients’ body movements. Sedative effects, such as the time to loss of consciousness (LOC) (MOAA/S score ≤ 1), successful sedation in one dose, number of supplemental doses after successful induction, and recovery time, were evaluated. Sedation-related side effects, such as injection pain, haemodynamic events and respiratory depression, were also noted. Postoperative nausea and vomiting (PONV), visual analogue scale (VAS) scores at rest, remedial analgesics, and dizziness or headache were recorded. In addition, patients’ satisfaction and physician’s satisfaction of the procedure were compared between the two groups.

Results

Data from 77 patients were analysed. The success rate of sedation in both groups was 100%. The time to LOC (MOAA/S score ≤ 1) in the RT group was longer than that in the propofol group (20.7 ± 6.1s vs. 13.2 ± 5.2s, P < 0.001). There were fewer patients in the RT group reporting injection pain than that in the propofol group (0/39 vs. 5/38, P = 0.025). Haemodynamic events and respiratory depression in the RT group were less frequent than those in the propofol group ((6/39 vs. 17/38, P = 0.005), (2/39 vs. 9/38, P = 0.026), respectively). The number of supplemental doses after successful induction in the RT group was greater than that in the propofol group (4/9/11/13/1/1 vs. 8/4/18/6/2/0 requiring 0, 1, 2, 3, 4 or 5 supplemental doses, P = 0.014). The characteristics of the patients enrolled, postoperative parameters of the patients, and patients’ and physician’s satisfaction of the procedure were comparable in the two groups.

Conclusions

Compared with propofol, RT can be safely and effectively used for gastrointestinal endoscopy sedation in elderly patients, and the incidence of sedation-related adverse reactions, especially haemodynamic events and respiratory depression, is lower. When RT is used, the number of supplemental doses after successful induction may increase slightly.

Trial registration

Chictr.org.cn ChiCTR2000040498. Retrospectively registered (date of registration: December 1, 2020).

Review of remimazolam and sedatives in the intensive care unit

Remimazolam is a novel intravenous ultra-short acting benzodiazepine that has the potential of being a safe and effective new sedative for use in intensive care unit (ICU) settings. Because remimazolam metabolizes rapidly by being hydrolyzed to an inactive metabolite (CNS 7054) through non-specific tissue esterase activity, specific dosing adjustment for older adults and for patients with renal or hepatic impairment patients (except for those with severe hepatic impairment) is not required. In addition, research has shown that remimazolam may be reversed by administration of flumazenil, as its half time was sufficiently short compared to flumazenil. It shows a lower incidence of cardiorespiratory depression, less injection pain, and no fatal complications such as propofol infusion syndrome and malignant hyperthermia of inhalational anesthetics. Future studies to study the suitability of remimazolam for managing the sedation of ICU patients who need sedation for a long time over several days is required.

Effect of remimazolam tosilate on early cognitive function in elderly patients undergoing upper gastrointestinal endoscopy

BACKGROUND AND AIM

Remimazolam tosilate (RT) is under evaluation as a sedative for endoscopic procedures. Herein, we aimed to evaluate safety including cognition recovery of RT administered in elderly patients undergoing upper gastrointestinal endoscopy and assess its safety dosage.

METHODS

Ninety-nine patients presenting for upper gastrointestinal endoscopy were randomized to receive 0.1 mg/kg RT (R1) or 0.2 mg/kg RT (R2), or propofol (P). Cognitive functions (memory, attention, and executive function) were measured via neuropsychological tests conducted before sedation and 5 min after recovery to full alertness. Adverse events were also assessed.

RESULTS

There were no statistical differences between postoperative and baseline results for R1 group and P group, whereas those for R2 group revealed worsened postoperative cognitive functions (immediate recall and short delay recall) than baseline (P < 0.05). Compared with P group, Scores demonstrated worse restoration of immediate recall in R1 group, immediate recall, short-delayed recall, and attention function in R2 group (P < 0.05). Patients in R2 group had a longer sedation time (12.09 vs 8.27 vs 8.21 min; P < 0.001) and recovery time (6.85 vs 3.82 vs 4.33 min; P < 0.001) than that in R1 group and P group. Moreover, the incidence of hypotension was 3.0% in R1 group, whereas it was 21.2% in R2 group and 48.5% in P group (P < 0.05).

CONCLUSION

The addition of 0.1 mg/kg RT as an adjunct to opiate sedation for upper gastrointestinal endoscopy not only achieves more stable perioperative hemodynamics but also achieves acceptable neuropsychiatric functions in elderly patients.

Remimazolam: pharmacological characteristics and clinical applications in anesthesiology

A novel ultra-short-acting benzodiazepine (BDZ), remimazolam (CNS 7056), has been designed by ‘soft drug’ development to achieve a better sedative profile than that of the current drugs. Notably, the esterase linkage in remimazolam permits rapid hydrolysis to inactivate metabolites by non-specific tissue esterase and induces a unique and favorable pharmacological profile, including rapid onset and offset of sedation and a predictable duration of action. Similar to other BDZs, its sedative effects can be reversed using flumazenil, a BDZ antagonist. The pharmacokinetics and pharmacodynamics of remimazolam are characterized by relatively high clearance, small steady-state volume of distribution, short elimination half-life, short context-sensitive half-life, and fast onset and recovery, indicating rapid elimination, minimal tissue accumulation, and good control. In addition, remimazolam possesses a superior safety profile, including low liability for cardiorespiratory depression and injection pain, making it a preferred hypnotic agent in various clinical settings. Early clinical investigations suggest that remimazolam is well tolerated and effective for procedural sedation and for induction and maintenance of general anesthesia. To date, however, the clinical use of remimazolam has been confined to a few volunteer studies and a limited number of clinical investigations. Therefore, further studies regarding its recovery issues or postoperative complications, characteristics of electroencephalogram changes, and cost-benefit analyses are required to facilitate its widespread use.

Efficacy and Safety of Remimazolam Tosilate versus Propofol for General Anesthesia in Cirrhotic Patients Undergoing Endoscopic Variceal Ligation

Introduction

The best candidate intravenous anesthetic agent for patients with liver cirrhosis undergoing endoscopic variceal ligation (EVL) remains unclear. Remimazolam tosilate (RT) is a new type of benzodiazepine with quick onset, rapid recovery, and no accumulation. Here, we investigated the efficacy and safety of RT for general anesthesia in cirrhotic patients undergoing EVL.

Methods

Patients undergoing EVL were randomly classified into the remimazolam tosilate (group R) and the propofol group (group P). RT was administered as a slow bolus of 0.2 mg/kg for induction and followed by 1.0–2.0 mg/kg/h for maintenance of general anesthesia. Propofol was started at 2 mg/kg, followed by 4–10 mg/kg/h until the end of surgery. Flumazenil was routinely administered to group R and the same volume of saline was given to group P immediately after surgery. The efficacy and safety of RT for general anesthesia during EVL were compared with propofol.

Results

All patients in the two groups had satisfactory anesthetic effects and the efficacy rates were 100%. The time to loss of consciousness (LoC) was longer in group R than in group P (P > 0.05). The return of consciousness (RoC) time, extubation time, and transfer time in group R were significantly shorter than that in group P (P < 0.05). The incidence of intraoperative hypotension and postoperative low SpO₂ in group R were lower than that in the group P (P < 0.05). There were no significant differences between the two groups with respect to the satisfaction degree of patients and operators (P > 0.05).

Conclusion

Remimazolam tosilate can provide satisfactory anesthetic effects for surgery. Group R patients recovered faster and had a shorter PACU stay time than group P patients. Moreover, RT decreased the incidence of hypotension and low SpO₂. RT was a safer and more effective alternative for general anesthesia in cirrhotic patients undergoing EVL than propofol.

Sedation/analgesia techniques for nonoperating room anesthesia: new drugs and devices

PURPOSE OF REVIEW

The purpose of this article is to review new drugs and devices for nonoperating room anesthesia (NORA).

RECENT FINDINGS

Remimazolam is an ultra-short-acting, water-soluble intravenous benzodiazepine with a fast onset and offset that has been approved recently for use in procedural sedation. Phase III trials have established the effectiveness of remimazolam sedation compared with placebo and midazolam in gastrointestinal endoscopy and bronchoscopy. More research is required investigating remimazolam in real-world NORA settings, including comparisons with propofol sedation. Oliceridine is a μ-agonist with selectivity for the G protein pathway and low potency for β-arrestin recruitment. As such it may be associated with less nausea, vomiting and respiratory depression than traditional opioids used. Although no studies have been published about oliceridine use in NORA to date, results from surgical studies indicate a potential place in nonoperating room practice. Research continues into alternative methods of drug delivery, such as patient-controlled sedation but no new devices are described.

SUMMARY

Further studies are required before these new drugs and devices are embraced in NORA.

The Efficacy and Safety of Remimazolam Tosilate versus Etomidate-Propofol in Elderly Outpatients Undergoing Colonoscopy: A Prospective, Randomized, Single-Blind, Non-Inferiority Trial

Objective

The optimal sedation regime during endoscopy remains controversial, especially for elderly outpatients. In this study, we compared the efficacy and safety between remimazolam tosilate (RT) and etomidate-propofol (EP) in elderly outpatients undergoing colonoscopy.

Methods

A total of 260 elderly outpatients undergoing sedative colonoscopy were randomized into two groups. Patients in the RT group received a 0.075-mg/kg maintenance dose of remimazolam following an initial dose of 0.15 mg/kg, whereas patients in the EP group (10 mL:20 mg etomidate plus 10 mL:100 mg propofol) received a 0.05-mL/kg maintenance dose following an initial dose of 0.1 mL/kg to maintain a Modified Observer’s Assessment of Alertness/Sedation score of ≤3 during the procedure. The primary endpoint was the success of the procedure. Secondary endpoints included time metrics, hemodynamics, consumption of fentanyl, etomidate, propofol, and remimazolam, intraoperative body movement, patient and endoscopist satisfaction scores, supplemental dose of sedative and fentanyl, and incidence and severity of adverse events.

Results

The procedure success rate was 96.52% in the RT group and 100% in the EP group. The difference in procedure success rate between the RT and EP groups was −3.48% (95% confidence interval: −6.81%, −0.15%). Four patients in the RT group required rescue midazolam. Compared with patients in the RT group, the onset time of the EP group was significantly lower (p < 0.05), whereas time to fully alert (p = 0.001), ready for discharge (p = 0.001), and hospital discharge (p = 0.002) were all significantly higher in the EP group. However, there were no significant differences in procedure time (p = 0.846) or cecal intubation time (p = 0.320) between the two groups. Although the frequency of intraoperative body movement was higher in the RT group, the difference was not significant (p = 0.508). There were no significant differences in patients’ demographic and baseline characteristics, supplemental doses of sedative and fentanyl, or patient and endoscopist satisfaction scores (p > 0.05). Muscular tremor and pain on injection were recorded more frequently in the EP group (p < 0.05). However, there were no significant differences in hypoxia, respiratory depression, or incidence of postoperative nausea and vomiting. The severity of adverse events was all mild (grade 1) across both groups.

Conclusion

RT may have non-inferior efficacy and a higher safety profile than EP in elderly outpatients undergoing colonoscopy, which suggests that RT may be more suitable for elderly outpatients undergoing colonoscopy.

A comprehensive review of remimazolam for sedation

Benzodiazepines are one of the most commonly used medications in the field of anesthesia. They offer excellent anxiolytic and amnestic properties ideal for the perioperative period when patient anxiety is understandably heightened. Remimazolam has presented a favorable alternative to some of the common intravenous anesthetic agents used given its fast onset of action, high safety profile, and reasonably short duration of action. The drugs within the four classes of benzodiazepines, 2-keto-benzodiazepines, 3-hydroxy-benzodiazepines, triazolo-benzodiazepines, and 7-nitro-benzodiazepines provide varying degrees of anxiolysis, sedation, and amnesia. This is provided by the benzodiazepine molecule binding and causing a conformational change to the chloride ion channel to cause hyperpolarization and thus inhibition of the central nervous system. Each type of benzodiazepine has a preferred role within the realm of medicine. For instance, diazepam is used for the treatment of seizures and anxiety. Midazolam's anxiolytic and anterograde amnestic properties are taking advantage of during the perioperative period. Lorazepam is beneficial for anxiety and status epilepticus. Remimazolam, currently in phase II and III clinical trials, has demonstrated a very short during of action and low context-sensitive half-time, allowing for its rapid removal even during a prolonged infusion. Much of its properties may be credited to being a soft drug, meaning it is a metabolically active drug that is rapidly inactivated in the body. This provides anesthesiologists and other practitioners administering it with a more predictable sedative. These properties have the potential to push it towards becoming the drug of choice for premedication during the perioperative period and sedation in the ICU. Furthermore, remimazolam does not seem to rely on any specific organ to be metabolized. The drug's ester moiety makes it a substrate for non-specific tissue esterase enzymes, meaning its metabolism and elimination are not impaired in patients with hepatic and/or renal disease. Its addictive potential closely resembles that of its parent compound, midazolam. Reports of its adverse reactions include headache and somnolence after an involuntary movement during infusion. Benzodiazepines are a great adjunct to anesthetic care. Remimazolam's safety profile, pharmacokinetics, pharmacodynamics, and potential practical use make it quite favorable in this regard. It has the potential to equip anesthesiologists and other medical practitioners with a more predictable medication that has a good safety profile. However, further large clinical trials will provide us with a better understanding of the advantages and disadvantages of remimazolam.

Effect of remimazolam besylate compared with propofol on the incidence of delirium after cardiac surgery: study protocol for a randomized trial

Background

Delirium is an acute cognitive disorder that presents with fluctuation in cognition, apathy, and non-organized thinking, resulting in increased morbidity, mortality, intensive care unit (ICU) stay, and total healthcare costs. In patients undergoing cardiac surgery, delirium also increases the risk of postoperative complications, such as respiratory insufficiency, sternum instability, and need for re-operation of the sternum. This study aims to understand the incidence of delirium in patients after cardiac surgery in patients sedated with remimazolam besylate versus propofol.

Methods

In this prospective, double-blind, randomized controlled clinical trial, we aim to recruit 200 patients undergoing cardiac surgery between January 1, 2021, and December 31, 2021, who will be randomized to receive either remimazolam besylate or propofol infusions postoperatively, until they are extubated. The primary outcome is the incidence of delirium within 5 days after surgery. Secondary outcomes include the time of delirium onset, duration of delirium, ICU length of stay, hospital length of stay, and mechanical ventilation time.

Discussion

The key objective of this study is to assess whether remimazolam besylate reduces the incidence of delirium in patients after cardiac surgery compared to propofol sedation. In this preliminary randomized controlled clinical trial, we will test the hypothesis that the use of remimazolam besylate lowers the incidence of delirium when compared to propofol in patients undergoing cardiac surgery.

Trial registration

chictr.org.cn ChiCTR2000038976. Registered on October 11, 2020

Efficacy and Safety of Remimazolam in Endoscopic Sedation-A Systematic Review and Meta-Analysis

Background: The aim of this systematic review and meta-analysis was to investigate the efficacy and safety of remimazolam in clinical endoscopic procedure sedation.

Methods: The authors searched the databases of PubMed, Embase, and Cochrane Library for studies published until January 2, 2021, that reported remimazolam sedation for endoscopic procedures. The sedative efficiency and the incidence of adverse events were assessed as outcomes. Cochrane Review Manager Software 5.3 was used to perform the statistical analyses.

Results: Seven relevant studies involving a total of 1,996 patients were identified. We conducted a meta-analysis of the different controls used in the studies, that is, the placebo, midazolam, and propofol. The results demonstrated that remimazolam had a strong sedative effect, and its sedative efficiency was significantly higher than that of placebo [OR = 0.01, 95% CI: (0.00, 0.10), I² = 30%, p <0.00001]. The sedative efficiency of remimazolam was significantly higher than that of midazolam [OR = 0.12, 95% CI: (0.08, 0.21), I² = 0%, p < 0.00001] but lesser than that of propofol [OR = 12.22, 95% CI: (1.58, 94.47), I² = 0%, p = 0.02]. Regarding the adverse events, remimazolam is associated with a lower incidence of hypotension than placebo and midazolam. Similarly, remimazolam was associated with a lower incidence of hypotension and hypoxemia than propofol.

Conclusions: Remimazolam is a safe and effective sedative for patients undergoing endoscopic procedures. The sedative efficiency of remimazolam was significantly higher than that of midazolam but slightly lower than that of propofol. However, the respiration and circulation inhibitory effects of remimazolam were weaker than those of midazolam and propofol.

Remimazolam: Non-Clinical and Clinical Profile of a New Sedative/Anesthetic Agent

A program to identify novel intravenous sedatives with a short and predictable duration of action was initiated in the late 1990's by Glaxo Wellcome. The program focussed on the identification of ester-based benzodiazepine derivatives that are rapidly broken down by esterases. Remimazolam was identified as one of the lead compounds. The project at Glaxo was shelved for strategic reasons at the late lead optimization stage. Via the GSK ventures initiative, the program was acquired by the small biotechnology company, TheraSci, and, through successive acquisitions, developed as the besylate salt at CeNeS and PAION. The development of remimazolam besylate has been slow by industry standards, primarily because of the resource limitations of these small companies. It has, however, recently been approved for anesthesia in Japan and South Korea, procedural sedation in the United States, China, and Europe, and for compassionate use in intensive care unit sedation in Belgium. A second development program of remimazolam was later initiated in China, using a slightly different salt form, remimazolam tosylate. This salt form of the compound has also recently been approved for procedural sedation in China. Remimazolam has the pharmacological profile of a classical benzodiazepine, such as midazolam, but is differentiated from other intravenous benzodiazepines by its rapid conversion to an inactive metabolite resulting in a short onset/offset profile. It is differentiated from other intravenous hypnotic agents, such as propofol, by its low liability for cardiovascular depression, respiratory depression, and injection pain. The benzodiazepine antagonist flumazenil can reverse the effects of remimazolam in case of adverse events and further shorten recovery times. The aim of this review is to provide an analysis of, and perspective on, published non-clinical and clinical information on 1) the pharmacology, metabolism, pharmacokinetics, and pharmacodynamic profile of remimazolam, 2) the profile of remimazolam compared with established agents, 3) gaps in the current understanding of remimazolam, 4) the compound's discovery and development process and 5) likely future developments in the clinical use of remimazolam.

Safety and efficacy of remimazolam compared with propofol in induction of general anesthesia

BACKGROUND

Remimazolam is a new ultra-short acting benzodiazepine anesthetic which has predictable sedative duration and rapid recovery in gastrointestinal endoscopy. Propofol is a commonly used intravenous anesthetic in clinical work which also has rapid action, short action time and rapid recovery. To date, there have been relatively few articles comparing the two for general anesthesia induction. So we conducted a randomized trial to evaluate whether remimazolam is superior to propofol during anesthesia induction in terms of the efficacy and safety.

METHODS

One hundred and eighty nine ASA I or II patients scheduled for elective surgery were divided into four groups: remimazolam 0.2mg/kg (group R1), 0.3mg/kg(group R2), 0.4mg/kg(group R3), and propofol group(group P). All patients were anesthetized with single shot of experimental drugs during induction period. Efficacy was measured by completing the induction of anesthesia without rescue sedation and safety was defined as no severe adverse events.

RESULTS

Success induction rates in remimazolam groups were 89%(group R1), 94%(group R2) and 100%(group R3) while success induction rate in group P was 100%. Hypotension rates during induction were lower in R1 group (13%) and R2 group (24%) compared with group P (44%). Hypotension rate in R3 group (34%) was similar to propofol (44%). Injection site pain in group P was 27% while no pain was observed in remimazolam groups.

CONCLUSIONS

Remimazolam is a safe and effective sedative drug during induction with less adverse effects for general anesthesia in ASA I or II patients.

Sedation outcomes for remimazolam, a new benzodiazepine

Remimazolam is a new ultrashort-acting benzodiazepine with fast onset, quick recovery, and few side effects, such as hypotension and respiratory depression. It is expected to be safe and effective for a wide range of patients undergoing intravenous sedation for dental procedures. The aim of this literature review was to evaluate clinical and sedation outcomes for remimazolam, including method of administration, level of sedation at the dose required, and clinical adverse events. An electronic literature search of databases was conducted, and eight articles were selected for inclusion in this review. Onset time from drug administration to optimal sedation level was faster for remimazolam (around 1.5-6.4 min) than for midazolam. Recovery time was significantly shorter for remimazolam than for midazolam and propofol. A study comparing various doses of remimazolam with midazolam found no significant difference in safety. Comparison of a remimazolam group with a propofol group showed that incidences of hypotension (13.0% vs 42.9%, respectively) and respiratory depression (1.1% vs 6.9%, respectively) were significantly lower for remimazolam. Remimazolam appears to be an ideal sedative.

Efficacy and safety of remimazolam besylate versus propofol during hysteroscopy: single-centre randomized controlled trial

Background

Remimazolam besylate is a newer benzodiazepine with characteristics of quick onset of effects, short maintenance and recovery times without accumulation in tissues. This trial was conducted to confirm the efficacy and safety of remimazolam besylate versus propofol during hysteroscopy.

Methods

Patients undergoing hysteroscopy were randomly assigned to either the remimazolam (Group R) or the propofol group (Group P). Group R was administered an induction dose of 0.2 mg/kg and a maintenance dosage of 1.0 mg/kg/h. In Group P, propofol was started at 1.5–2.0 mg/kg and then maintained at 3.0–6.0 mg/kg/h. After remimazolam besylate or propofol induction, remifentanil was infused using a target-controlled infusion system with a target concentration of 1.5 ng/ml and titrated during the procedure. The incidence rates of injection pain, low oxygen saturation (SpO₂) and adverse effects in both groups were compared.

Results

Eighty-two patients were included in this study. The incidence of adverse events in Group R (3.7%) was significantly lower than that in Group P (36.6%) (p < 0.001). The incidence of injection pain in Group P (80.5%) was much higher than that in Group R (2.4%) (p < 0.001). The incidence of other adverse events, such as low SpO₂, bradycardia, and hypotension in Group R was lower than that in Group P (p < 0.05).

Conclusions

Remimazolam besylate proves to be a safer alternative for anesthesia during hysteroscopy. Moreover, adverse events caused by propofol, such as low SpO₂ and injection pain, are largely avoided.

Trial registration

This study was approved by the Clinical Research Ethics Committee of Mengcheng County No. 1 People’s Hospital (2020MYL20003) and registered at http://www.chictr.org.cn (15/09/2020, ChiCTR-2000038252). The study protocol followed the CONSORT guidelines. The study protocol was performed in the relevant guidelines.

Emerging Approaches in Intravenous Moderate and Deep Sedation

Successful pharmacological innovations that have made a difference in daily practice are rare in the world of anesthesia and sedation. After many years of research, it seems that we finally have two new drug innovations that are likely to change the paradigm of moderate and deep sedation. These are oliceridine and remimazolam. Both have been in development for over a decade. Oliceridine was synthesized in a lab as an entirely new molecule. It is a biased μ- receptor agonist that acts preferentially on the G-protein pathway (which is responsible for analgesia). At least in lower doses, it has minimal effect on the beta-arrestin pathway, which is responsible for unwanted effects of μ-opioid receptor activation such as respiratory depression and gastrointestinal dysfunction. Like any other μ- receptor agonist, it produces appropriate dose-dependent analgesia. Remimazolam is structurally similar to midazolam; however, it has an additional ester linkage that delivers the kinetics of remifentanil. As a result, while pharmacodynamically identical to midazolam, remimazolam is metabolized by ester hydrolysis and subsequently its elimination is rapid and predictable. The present review discusses the two drugs in detail with a particular emphasis on their potential role in moderate and deep sedation.

Induction and maintenance of procedural sedation in adults: focus on remimazolam injection

Introduction: Procedural sedation (PS) is a humane way to help patients get through painful medical procedures by the administration of sedative drugs combined with analgesics. However, each of the currently used medications has certain shortcomings, urging the search for a new drug. Remimazolam, a novel benzodiazepine, is an ultra-short-acting hypnotic agent invented out of the 'soft drug' development.Areas covered: This presented review provides an overview of the drugs used in clinical practice for the induction and maintenance of procedural sedation in adults, focusing on the newly investigated benzodiazepine remimazolam. Literature search was conducted using the MEDLINE and ClinicalTrial.gov databases from January 2007 to December 2020.Expert opinion: Based on the reported clinical trials so far, remimazolam has demonstrated its effectiveness and safety with promising properties including rapid onset, short duration of action, predictable and consistent recovery profile, metabolism almost unaffected by liver or renal function, with non or minimal cardiorespiratory depression, and availability with a reversal drug. With marketing approval received recently, remimazolam is expected to have a place in the practice for procedural sedation in the near future if its efficacy and safety are further confirmed by more clinical trials and post-market analyses.