Association between remimazolam and postoperative delirium in older adults undergoing elective cardiovascular surgery: a prospective cohort study

Incidence and predictors of postoperative delirium following remimazolam administration: a systematic review and meta-analysis of 29 randomized trials

BACKGROUND

Postoperative delirium is a significant and common complication in surgical patients, particularly in vulnerable populations such as the elderly. Remimazolam, a novel benzodiazepine, has been introduced as an anesthetic agent with a favorable pharmacokinetic profile. However, its potential association with postoperative delirium remains unclear. This study aims to systematically synthesize available evidence on the incidence of delirium following remimazolam administration in surgical patients. We sought to identify significant moderators of delirium incidence and to explore predictors of delirium through meta-regression analysis.

METHODS

A comprehensive literature search was conducted across multiple databases, including PubMed, Scopus, Web of Science, Cochrane Library, and Google Scholar, up to May 20, 2024. The search was updated on Feb 2nd, 2025. Randomized trials were selected based on predefined criteria, and data on patient characteristics, surgical details, and delirium incidence were extracted. A meta-analysis was performed to calculate the pooled incidence rate of delirium, and subgroup and meta-regression analyses were conducted to identify incidence rate moderators.

RESULTS

A total of 29 RCTs, including 2,435 patients, were analyzed. The pooled incidence of postoperative delirium following remimazolam administration was 5% (95%CI: 3-7%). ASA III-IV patients had a delirium rate of 19% (95%CI: 15-23%) compared to 1% (95%CI: 0-1%) for ASA I-II. Age was a key factor, with children showing the highest rate (11%, 95%CI: 3-19%), followed by elderly patients (8%, 95%CI: 4-13%), while adults had the lowest (1%, 95%CI: 0-2%). Delirium incidence was highest in oncologic (16%, 95%CI: 0-34%) and orthopedic surgeries (12%, 95%CI: 9-14%), and lowest in gastrointestinal and endoscopic procedures (0%, 95%CI: 0-1%). High-dose remimazolam was linked to the lowest delirium incidence, while moderate doses had higher rates. Meta-regression identified surgery type as the primary predictor, with orthopedic surgery having the highest risk compared to laparoscopic and abdominal procedures (coefficient = 0.081, p = 0.03).

CONCLUSIONS

Postoperative delirium occurs in 5% of surgical patients following remimazolam administration. Key moderators include ASA classification, age, surgery type, and anesthetic dosing. Remimazolam may be safely used in surgical patients, particularly when higher doses are administered, but caution is warranted in high-risk populations such as elderly patients and those undergoing complex surgical procedures.

The Effects of Remimazolam and Inhalational Anesthetics on the Incidence of Postoperative Hyperactive Delirium in Geriatric Patients Undergoing Hip or Femur Surgery Under General Anesthesia: A Retrospective Observational Study

Background and Objectives: Postoperative delirium (POD) is a transient but significant complication in geriatric patients following hip or femur surgery. POD occurs in 19-65% of patients after hip surgeries, with notable risks associated with augmented morbidity, mortality, and prolonged hospitalization. The perioperative administration of benzodiazepines, particularly midazolam, is associated with an increased incidence of POD. Remimazolam, a novel ultra-short-acting benzodiazepine, has potential benefits, such as hemodynamic stability and ease of reversal, but its effect on POD occurrence remains unclear. Materials and Methods: This retrospective study investigated patients who were aged 65 years old and older who underwent hip or femur surgery. Following the application of exclusion criteria, 502 patients were grouped according to whether anesthesia was maintained with remimazolam (R group) or sevoflurane (S group). Data regarding patients' baseline characteristics, anesthetic details, and postoperative outcomes, including the incidence of POD, were gathered and analyzed. Propensity score matching and logistic regression were conducted to identify factors associated with POD and compare outcomes between the two groups. Results: Among the 502 patients, POD was observed in 161 (32%). The POD incidence was not statistically significantly different between the groups (p = 1.000). A multivariable logistic regression analysis indicated that remimazolam was not a determinant of POD (p = 0.860), whereas being male and polypharmacy were (p = 0.022; p = 0.047). Initial disparities in age and comorbid conditions between the groups were rectified through matching, demonstrating that remimazolam had a similar POD risk to sevoflurane. Conclusions: This study showed that remimazolam did not exacerbate the risk of POD in elderly patients undergoing hip or femur surgery. Remimazolam is a reliable anesthetic option for this vulnerable demographic. Also, this study's results indicated that polypharmacy and being male are POD risk factors, suggesting that meticulous perioperative medication management may help alleviate the risk of POD.

Remimazolam in Cardiac Anesthesia: Analysis of Recent Data

Interest in remimazolam has surged in recent years, thanks to its advantageous pharmacologic profile. This ultra-short-acting benzodiazepine is noted for its rapid onset and termination of action, organ-independent elimination, availability of a reversal agent, and excellent hemodynamic stability. Although the use of remimazolam has been explored in various anesthesia settings and procedures, data on its application in cardiovascular anesthesia and catheterization laboratory procedures remain limited. This review evaluates the latest literature to assess remimazolam's role in cardiovascular anesthesia across different settings and procedures. The analysis shows that remimazolam offers anesthesia without significant hemodynamic instability and a reduced need for vasopressors, with an incidence of perioperative adverse events comparable to that of other agents. These findings are relevant for both the induction and maintenance of general anesthesia in catheterization laboratory procedures and general anesthesia in elective cardiac surgery. Although further research is needed to fully understand remimazolam's role in cardiovascular anesthesia, its favorable hemodynamic and safety profile suggests that it is a promising option for cardiac anesthesiologists in both the catheterization laboratory and the operating room.

The impact of remimazolam compared to propofol on postoperative delirium: a systematic review and meta-analysis

INTRODUCTION

The administration of benzodiazepines has been linked to the occurrence of postoperative delirium (POD) among patients undergoing surgery. In this review, we aim to appraise the current controversy regarding the role of remimazolam in POD.

EVIDENCE ACQUISITION

A systematic review and meta-analysis of randomized controlled trials was conducted to examine the effects of remimazolam administration on postoperative delirium compared to propofol from inception to April 2024. We conducted a comprehensive search of PubMed, EMBASE, Cochrane Library, Web of Science, Wanfang, and ZhiWang Chinese databases. In the fixed-effects and random-effects statistical models, pooled risk ratios (RRs) or mean differences, 95% CIs, and P values were estimated for endpoints. The trial sequential analysis was used for sensitivity analysis.

EVIDENCE SYNTHESIS

Among the 479 records screened, 11 randomized controlled trials with 1682 patients were eligible for inclusion. POD did not differ between groups (RR,0.82; 95% CI 0.53-1.26; P=0.36; df=10; I2=42%). There were no statistically significant differences between groups in the incidence of nausea and vomiting, hypoxemia, and length of stay. However, remimazolam had a lower incidence of hypotension and bradycardia than propofol. Analyses of subgroups did not reveal a difference in delirium based on the type of surgery, assessment timing, or definition of cognitive impairment. This result has been supported by the trial sequential analysis.

CONCLUSIONS

Based on the available evidence, perioperative remimazolam administration is not associated with a significant rise in the incidence of POD.

Anesthesia management using remimazolam for coronary artery bypass grafting and aortic valve replacement in a patient with severe cardiac dysfunction: A case report

Remimazolam, a short-acting benzodiazepine approved for use in general anesthesia in Japan in 2020, has cardiovascular stability superior to conventional anesthetics. Anesthesia management using remimazolam of a patient with impaired cardiac function and several complications is reported. A man in his 50s with hypertension, diabetes mellitus, and chronic kidney disease (G 5) on dialysis came to our hospital with a chief complaint of exertional dyspnea and chest tightness, and a close examination showed stenoses of three coronary arteries. The patient was managed under anesthesia using remimazolam as a sedative because anesthetics could easily induce circulatory failure. Cardiopulmonary bypass was initiated without causing any circulatory failure, and coronary artery bypass grafting and aortic valve replacement were performed. The patient was successfully weaned with a small dose of catecholamine. Remimazolam was selected for this patient because of its minimal effect on cardiac rhythm, and the anesthesia was safely administered.

Retrospective comparison of the effects of remimazolam and dexmedetomidine on postoperative delirium in elderly patients undergoing orthopedic surgery of the lower extremities under spinal anesthesia

PURPOSE

Remimazolam is often used for perioperative sedation due to its rapid onset and offset. However, the possible association between remimazolam and postoperative delirium (POD) remains undetermined. The present study evaluated whether remimazolam increased the incidence of POD compared with dexmedetomidine in elderly patients undergoing orthopedic surgery of the lower extremities.

METHODS

This retrospective study included patients aged ≥ 65 years who had undergone orthopedic surgery of the lower extremities under spinal anesthesia from January 2020 to November 2022 and were sedated with continuous intravenous infusion of dexmedetomidine or remimazolam. The incidence of POD was assessed through a validated comprehensive review process of each patient's medical records. The effect of remimazolam on the occurrence of POD compared with dexmedetomidine was evaluated by propensity score weighted multivariable logistic models.

RESULTS

A total of 447 patients were included in the final analysis. The crude incidence of POD within 3 days after surgery was 7.5% (17/226) in the dexmedetomidine group and 11.8% (26/221) in the remimazolam group, increasing to 9.7% (22/226) and 15.8% (35/221), respectively (p = 0.073), within 5 days. The multivariable models showed that, compared with dexmedetomidine, intraoperative sedation with remimazolam significantly increased the occurrence of POD within 3 days (odds ratio [OR] 2.21, 95% confidence interval [CI] 1.31 to 3.82, p = 0.003) and 5 days (OR 2.10, 95% CI 1.32 to 3.40, p = 0.002).

CONCLUSION

Compared with dexmedetomidine, remimazolam infusion may be associated with a higher risk of POD in elderly patients undergoing orthopedic surgery of the lower extremities under spinal anesthesia.

Remimazolam Use in Cardiac Anesthesia: A Narrative Review

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

Effects of Surgery on Hemodynamics and Postoperative Delirium in Stanford Type A Aortic Dissection

Objective

To investigate the impact of surgical intervention on hemodynamic parameters and postoperative delirium in Stanford Type A aortic dissection patients.

Methods

A retrospective analysis was conducted on 139 patients who underwent surgery for Stanford Type A aortic dissection from February 2022 to February 2024. Hemodynamic parameters, including maximum ascending aortic diameter (MAAD), left ventricular end-diastolic diameter (LVEDd), and ejection fraction (LVEF), were compared pre- and post-surgery. Patients were divided into two groups based on delirium occurrence postoperatively: Group A (n=49, with delirium) and Group B (n=90, without delirium). Differences in surgical factors and intensive care conditions were analyzed, and risk factors for postoperative delirium were identified. Group sizes differ due to retrospective categorization based on observed outcomes rather than controlled sampling.

Results

① Hemodynamic parameters: Postoperative MAAD and LVEDd were significantly reduced, while LVEF increased compared to preoperative levels (P < 0.05). ② Surgical and postoperative conditions: Group A had longer surgery, cardiopulmonary bypass, and deep hypothermic circulatory arrest times than Group B (P < 0.05). ③ Univariate analysis of baseline data: Group A had higher rates of patients aged ≥60, hypertension, history of stroke, and elevated preoperative D-dimer levels (P < 0.05). ④ Multivariate logistic analysis: Independent risk factors for postoperative delirium included age ≥60, hypertension, history of stroke, surgery time >6 hours, cardiopulmonary bypass time >3 hours, and deep hypothermic circulatory arrest time >40 minutes (OR > 1, P < 0.05).

Conclusion

Surgical treatment of Stanford Type A aortic dissection has a good effect, significantly improving long-term cardiac function. However, the incidence of postoperative delirium is relatively high and is closely related to factors such as age, hypertension, history of stroke, surgery time, cardiopulmonary bypass time, and deep hypothermic circulatory arrest time.

Efficacy and safety of remimazolam tosylate for patients undergoing off-pump coronary artery bypass grafting: a study protocol for a non-inferiority randomised controlled trial in China

INTRODUCTION

Maintaining haemodynamic stability is crucial but challenging during the induction and maintenance of general anaesthesia (GA) in patients undergoing off-pump coronary artery bypass grafting (OPCABG). Remimazolam tosylate is a novel ultra-short-acting benzodiazepine with minimal cardiovascular depression. Currently, non-inferior studies comparing the haemodynamic changes induced by remimazolam and etomidate are limited. This study aims to assess the efficacy and safety of remimazolam tosylate for the induction and maintenance of GA in patients undergoing OPCABG.

METHOD AND ANALYSIS

This two-armed non-inferiority randomised controlled trial will include 88 patients aged 18-75 years who are scheduled for OPCABG. Patients will be randomly assigned in a 1:1 ratio to receive either remimazolam tosylate or etomidate and propofol for anaesthesia induction and maintenance. The primary outcome will be the fluctuation of mean artery pressure during anaesthesia induction. Secondary outcomes will include adverse events, adverse drug reactions, the cumulative dosage of vasoactive drugs, vital signs and bispectral index values at different time points, lengths of postoperative mechanical ventilation and tracheal intubation, lengths of intensive care unit stay and hospital stay and hospital mortality. Analyses will be conducted using both the intention-to-treat approach and the per-protocol approach.

ETHICS AND DISSEMINATION

This study was approved by the Ethics Committee of Zibo Central Hospital (No. 2024001). The trial results will be submitted to an international peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ChiCTR.gov.cn: ChiCTR2400079615.

The efficacy and safety of remimazolam tosilate compared with propofol for endoscopic retrograde cholangiopancreatography under monitored anesthesia care: A single-center randomized controlled clinical trial

BACKGROUND

Although remimazolam tosilate is an ultra-short-acting benzodiazepine that causes less respiratory and circulatory depression than propofol, studies evaluating its efficacy and safety during endoscopic retrograde cholangiopancreatography (ERCP) are limited. This study aimed to compare the efficacy and safety of remimazolam and propofol for ERCP performed under monitored anesthesia care (MAC).

METHODS

This study is a randomized controlled clinical trial featuring a noninferiority design. A total of 102 eligible patients undergoing ERCP under MAC were randomly assigned to either the remimazolam tosilate group (R group) or the propofol group (P group) in a 1:1 ratio. Patients in the R group were sedated with remimazolam tosilate, while those in the P group received propofol, both under MAC. The primary efficacy endpoint was the success rate of ERCP completion under MAC. Secondary outcomes included the time to loss of consciousness, sedative effects, and perioperative adverse events at various time points for patients in both groups.

RESULTS

Baseline characteristics of both groups were similar. The successful completion rate for ERCP under MAC was 100 % in the R group and 96.1 % in the P group, resulting in a difference of 3.92 % (95 % CI: -2%, 10 %). This difference met the pre-established criterion of being greater than -8%. The total number of norepinephrine infusions, as well as the incidence of intravenous injection pain, post-induction hypotension, post-induction bradycardia, intraoperative hypotension, respiratory depression, and hypoxemia, were significantly lower in the R group compared to the P group. Conversely, the total number of phloroglucinol uses, body movements, and instances of rapid gastrointestinal peristalsis were significantly higher in the R group than in the P group.

DISCUSSION

Remimazolam-based MAC for ERCP exhibited non-inferior efficacy compared to propofol-based MAC, while also resulting in fewer circulatory and respiratory adverse events during the procedures. Nevertheless, future studies with larger sample sizes are required to evaluate the utility of remimazolam in elderly patients.

Age-Related Response to Remimazolam among Older Patients Undergoing Orthopedic Surgery: A Single-Center Prospective Observational Study

Background and Objectives: Remimazolam, an ultra-short-acting benzodiazepine, is increasingly used in procedural sedation and general anesthesia. It is characterized by rapid onset of action, inactive metabolites, no delay in recovery, and few adverse events. Its hemodynamic and respiratory stability are comparable to other anesthetics, and it is safe in high-risk and geriatric patients. Materials and Methods: This prospective, observational study enrolled 110 geriatric patients (aged 65 to 85 years) scheduled for primary total knee arthroplasty (TKA). The patients were divided into the old (65 to <75 years; n = 52) and the elderly (75 to 85 years; n = 47) geriatric groups. All surgical and anesthetic methods were applied in the same manner, and TKA was performed by one surgeon. Remimazolam was infused at 6 mg/kg/h for 3 min and then at 1 mg/kg/h until the end of surgery The primary study endpoint was the requirement for flumazenil; secondary endpoints were the times to reach a bispectral index (BIS) < 60 and >80, as well as the rate of apnea occurrence. Results: Flumazenil administration was similar in both groups. There were no differences in the time to reach BIS < 60 or the rate of apnea occurrence. Recovery characteristics, including the time to reach BIS > 80 and the achievement of full consciousness, were also comparable between the groups. Conclusions: Remimazolam is well-tolerated in geriatric patients undergoing orthopedic surgery, with minimal age-related differences in response. These results suggest that remimazolam is an appropriate anesthetic for geriatric patients, even with similar dosing strategies. It provides effective anesthetic depth with no significant increases in adverse outcomes during orthopedic surgery.

The effect of two different modes of anaesthesia maintenance on postoperative delirium in elderly patient with low preoperative mini-cog score

BACKGROUND

Postoperative delirium is a common distressing symptom experienced following laparoscopic cholecystectomy. The study aimed to investigate the influence of a low preoperative Mini-Cog testing score and 2 different anesthesia methods: total intravenous anaesthesia (TIVA) versus sevoflurane, on postoperative delirium in elderly patients undergoing laparoscopic cholecystectomy.

METHODS

A total of 84 patients over 60 years old who underwent laparoscopic cholecystectomy between March 1and - October 1 2023 were included in the study. Patients with a Mini-Cog score of 0-2 were considered to have low and possibly impaired neurocognitive function. We invastigated the effects of preoperative Mini-Cog score and the two anesthesia methods used on the incidence of postoperative delirium.

RESULTS

The proportion of patients with low Mini-Cog score in the preoperative period was 17.9%. Sevoflurane and TIVA was used in 41 and 43 patients respectively. The incidence of postoperative delirium in patients with low preoperative Mini-Cog scores was 66.7% at postoperative 0 h and 33.3% at the 1st hours. Postoperative delirium was found to be statistically higher in patients with low Mini-cog scores than in those with negatively-screened for Mini-cog scores (p: 0.01-0.035). In patients using sevoflurane, the incidence of postoperative delirium was 26.8% and 24.4% at the 0 and 1st hours, respectively. This was found to be statistically higher than in patients receiving TIVA (p: 0.036 - 0.010).

CONCLUSION

Low Mini-Cog score was an indicator of a higher risk of early postoperative delirium. Sevoflurane is more likely to cause postoperative delirium than TIVA.

TRIAL REGISTRATION

The study was registered on ClinicalTrials.gov (Identifier: NCT06597812) .

Effects of remimazolam versus dexmedetomidine on recovery after transcatheter aortic valve replacement under monitored anesthesia care: a propensity score-matched, non-inferiority study

BACKGROUND

Minimalist transcatheter aortic valve replacement (TAVR) under monitored anesthesia care (MAC) emphasizes early recovery. Remimazolam is a novel benzodiazepine with a short recovery time. This study hypothesized that remimazolam is non-inferior to dexmedetomidine in terms of recovery after TAVR.

METHODS

In this retrospective observational study, remimazolam was compared to dexmedetomidine in patients who underwent TAVR under MAC at a tertiary academic hospital between July 2020 and July 2022. The primary outcome was timely recovery after TAVR, defined as discharge from the intensive care unit within the first day following the procedure. Propensity score matching was used to compare timely recovery between remimazolam and dexmedetomidine, applying a non-inferiority margin of -10%.

RESULTS

The study included 464 patients, of whom 218 received remimazolam and 246 received dexmedetomidine. After propensity score matching, 164 patients in each group were included in the analysis. Regarding timely recovery after TAVR, remimazolam was non-inferior to dexmedetomidine (152 of 164 [92.7%] in the remimazolam group versus 153 of 164 [93.3%] in the dexmedetomidine group, risk difference [95% CI]: -0.6% [-6.7%, 5.5%]). The use of remimazolam was associated with fewer postoperative vasopressors/inotropes (21 of 164 [12.8%] vs. 39 of 164 [23.8%]) and temporary pacemakers (TPMs) (76 of 164 [46.3%] vs. 108 of 164 [65.9%]) compared to dexmedetomidine.

CONCLUSIONS

In patients undergoing TAVR under MAC, remimazolam was non-inferior to dexmedetomidine in terms of timely recovery. Remimazolam may be associated with better postoperative recovery profiles, including a lesser need for vasopressors/inotropes and TPMs.

[Remimazolam-Update on basic pharmacologic principles and clinical potential]

In recent years the still relatively new short-acting benzodiazepine remimazolam has been approved and clinically implemented in several countries and regions. Remimazolam is also now approved in the EU and the market launch in Germany is expected in the not too distant future. This is therefore a good point in time to summarize the current evidence for various areas of application, including general anesthesia, sedation and intensive care medicine as well as different dosing schemes.

Comparison of remimazolam and desflurane in emergence agitation after general anesthesia for nasal surgery: a prospective randomized controlled study

BACKGROUND

Remimazolam is an ultrashort-acting benzodiazepine. Few studies have evaluated the effects of remimazolam-based total intravenous anesthesia (TIVA) on emergence agitation (EA). This study aimed to compare the incidence and severity of EA between TIVA using remimazolam and desflurane.

METHODS

This prospective randomized controlled study enrolled 76 patients who underwent nasal surgery under general anesthesia. Patients were randomized into two groups of 38 each: desflurane-nitrous oxide (N2O) (DN) and remimazolam-remifentanil (RR) groups. The same protocol was used for each group from induction to emergence, except for the use of different anesthetics during maintenance of anesthesia according to the assigned group: desflurane and nitrous oxide for the DN group and remimazolam and remifentanil for the RR group. The incidence of EA as the primary outcome was evaluated using three scales: Ricker Sedation-Agitation Scale, Richmond Agitation-Sedation Scale, and Aono's four-point agitation scale. Additionally, hemodynamic changes during emergence and postoperative sense of suffocation were compared.

RESULTS

The incidence of EA was significantly lower in the RR group than in the DN group in all three types of EA assessment scales (all P < 0.001). During emergence, the change in heart rate differed between the two groups (P = 0.002). The sense of suffocation was lower in the RR group than in the DN group (P = 0.027).

CONCLUSIONS

RR reduced the incidence and severity of EA in patients undergoing nasal surgery under general anesthesia. In addition, RR was favorable for managing hemodynamics and postoperative sense of suffocation.

Effectiveness of remimazolam in preventing postoperative delirium in elderly patients with proximal femoral fractures

PURPOSE

Elderly patients with proximal femoral fractures are known to be a high-risk group for postoperative delirium (POD). The aim of this study was to determine the association of the benzodiazepine drug remimazolam with POD in elderly patients with proximal femoral fractures.

METHODS

In this single-center retrospective observational study, we included patients aged 65 years or older who underwent general anesthesia for proximal femoral fractures. We collected data for the incidence of POD within 3 days after surgery. We also obtained data for complications, preoperative blood examinations, maintenance anesthetic and intraoperative vital data. The occurrence of POD in patients who received remimazolam for general anesthesia (remimazolam group) was compared to that in patients who received general anesthesia with other anesthetic agents (other group). We finally conducted a multivariate analysis to assess the independent association of remimazolam with the risk of POD.

RESULTS

A total of 230 patients, including 54 patients who received remimazolam for maintenance anesthesia, were included in this study. The incidence of POD in the patients was 26.1%. The incidence of delirium within 3 days after surgery was significantly lower in the remimazolam group than in the other group (14.8% vs. 29.5%, p  =  0.03). The multivariate analysis showed that the use of remimazolam independently reduced the occurrence of POD (adjusted odds ratio  =  0.42, p  =  0.04).

CONCLUSION

This retrospective observational study showed that the use of remimazolam is independently associated with a reduced incidence of POD. Remimazolam may be considered as an option to reduce POD in elderly patients with proximal femoral fractures.

Remimazolam: its clinical pharmacology and evolving role in anesthesia and sedation practice

PURPOSE OF REVIEW

Remimazolam is a novel benzodiazepine anesthetic/sedative, designed as a rapidly metabolized carboxylic acid. Since its recent launch, the role of remimazolam in modern anesthesia and sedation practice is still evolving. This review aims to outline the clinical pharmacology and clinical utility of remimazolam to elucidate its potential advantages and limitations.

RECENT FINDINGS

Remimazolam is "short-acting" but not ultra-short-acting compared with propofol based on context-sensitive decrement times. But compared to propofol, the availability of the benzodiazepine antagonist, flumazenil, is considered an advantage, particularly in certain emergency situations such as in patients with difficult airways. However, because flumazenil is shorter acting than remimazolam when remimazolam accumulates or is present in a high concentration, the reappearance of remimazolam sedation may occur after the initial reversal of anesthesia/sedation from flumazenil administration. Although it is beneficial that remimazolam causes less respiratory depression and hypotension than propofol, serious respiratory depression and hypotension can still occur. Remimazolam administration causes minimal or no pain on injection. Remimazolam is associated with less postoperative nausea and vomiting than inhaled anesthetics, but propofol is clearly superior in this regard. The anesthetic/sedative effects may be prolonged by severe hepatic impairment; remimazolam tolerance can occur in long-term benzodiazepine users.

SUMMARY

Remimazolam may be beneficial to use in procedural sedation and general anesthesia for patients with difficult airways or hemodynamic instability. Further clinical studies with remimazolam are warranted to identify the potential benefits in other settings and patient populations.

Effects of Remimazolam versus Sevoflurane on Hemodynamics in Patients Undergoing Coil Embolization of Cerebral Aneurysm: A Prospective Randomized Controlled Trial

Background: Cerebral aneurysm coil embolization is often performed under general anesthesia to prevent patient movement and sudden high blood pressure. However, the optimal anesthetic agent remains uncertain. This study aimed to determine whether maintaining anesthesia with remimazolam in patients undergoing coil embolization could avoid hypotension or hypertension compared to sevoflurane. Methods: Thirty-three adult patients participated in this single-blinded, randomized controlled trial. Patients in Group R were induced and maintained with remimazolam, whereas those in Group S received propofol and sevoflurane. Results: The use of remimazolam significantly reduced the incidence of intraoperative hypotension events (33.3% vs. 80.0%; p = 0.010) but did not change the incidence of hypertension events (66.7% vs. 73.3%; p = 0.690). Patients in Group R maintained a significantly higher range of maximal (100.2 ± 16.6 vs. 88.1 ± 13.5 mmHg; p = 0.037) and minimal (69.4 ± 6.6 vs. 63.4 ± 4.8 mmHg; p = 0.008) mean arterial blood pressure than those in Group S during the intervention. Conclusions: This is the first study to demonstrate the feasibility of maintaining general anesthesia with remimazolam in patients undergoing cerebral aneurysm coil embolization. The findings suggest that remimazolam may maintains better hemodynamic stability, reducing the incidence of hypotensive events without compromising patient safety.

Remimazolam for anesthesia and sedation in cardiac surgery and for cardiac patients undergoing non-cardiac surgery: a systematic-narrative hybrid review

INTRODUCTION

Remimazolam, an ultra-short-acting benzodiazepine recognized and approved as an anesthetic and sedative in multiple countries, offers a distinctive pharmacokinetic profile, boasting advantages such as rapid onset, short action duration, and rapid recovery. These attributes may contribute to enhanced hemodynamic stability and a diminished risk of respiratory depression compared to other sedatives.

EVIDENCE ACQUISITION

We conducted the first comprehensive systematically structured narrative review to evaluate the role and potential application of remimazolam in cardiac surgery. Twenty-one studies published from 2021 to 2023 delved into remimazolam's application in open cardiac surgery, cardiac catheterization or electrophysiology laboratories, and high-risk cardiovascular patients undergoing non-cardiac surgery.

EVIDENCE SYNTHESIS

Overall, remimazolam usage was apparently linked to potentially superior hemodynamic stability compared to other hypnotic drugs. However, findings regarding the reduction in postoperative delirium incidence with remimazolam and the doses of remimazolam for anesthesia induction and maintenance were inconsistent across the studies.

CONCLUSIONS

Though remimazolam has demonstrated potential safety, efficacy, and ease-of-use for both anesthesia induction and maintenance in cardiac surgery patients and high-risk cardiovascular patients undergoing non-cardiac surgery, further research is imperative to delve into specific patient subgroups (e.g., the elderly or emergent procedures) so as to ascertain optimal dose ranges to suit diverse clinical scenarios.

Remimazolam for simultaneous percutaneous mitral valve clip and percutaneous left atrial appendage closure in an elderly patient with impaired cardiac function: A case report

Remimazolam is a short-acting benzodiazepine sedative with a short half-life and little circulatory depression. The safe use of remimazolam in the anesthetic management of an elderly patient with impaired cardiac function is reported. The patient's hemodynamics remained stable, and the patient was managed without serious complications. Remimazolam may be an option for sedation in elderly patients with reduced cardiac function.

The Effects of Appropriate Perioperative Exercise on Perioperative Neurocognitive Disorders: a Narrative Review

Perioperative neurocognitive disorders (PNDs) are now considered the most common neurological complication in older adult patients undergoing surgical procedures. A significant increase exists in the incidence of post-operative disability and mortality in patients with PNDs. However, no specific treatment is still available for PNDs. Recent studies have shown that exercise may improve cognitive dysfunction-related disorders, including PNDs. Neuroinflammation is a key mechanism underlying exercise-induced neuroprotection in PNDs; others include the regulation of gut microbiota and mitochondrial and synaptic function. Maintaining optimal skeletal muscle mass through preoperative exercise is important to prevent the occurrence of PNDs. This review summarizes current clinical and preclinical evidence and proposes potential molecular mechanisms by which perioperative exercise improves PNDs, providing a new direction for exploring exercise-mediated neuroprotective effects on PNDs. In addition, it intends to provide new strategies for the prevention and treatment of PNDs.

Effect of remimazolam versus propofol anesthesia on postoperative delirium in neurovascular surgery: study protocol for a randomized controlled, non-inferiority trial

BACKGROUND

Remimazolam is a short-acting benzodiazepine newly approved for the induction and maintenance of general anesthesia. Remimazolam emerges as an ideal drug for the neurosurgical population due to its rapid emergence, enabling early neurological assessment, and its ability to maintain perfusion pressure, which is crucial for preventing cerebral ischemia. However, the use of benzodiazepine has been associated with an increased risk of postoperative delirium (POD). There is currently limited evidence about the relationship between remimazolam-based total intravenous anesthesia (TIVA) and POD.

METHODS

In this double-blind, randomized, non-inferiority trial, we plan to include 696 adult patients with American Society of Anesthesiologists physical status class I to III, undergoing elective neurovascular surgery under general anesthesia. After informed consent, the patients will be randomized to receive either remimazolam or propofol-based TIVA with a 1:1 ratio. The primary outcome is the incidence of POD within 5 days after surgery. Secondary outcomes include subtypes, number of positive assessments and severity of POD, emergence agitation, intraoperative awareness and undesirable patient movement, intraoperative hypotension, and postoperative cognitive function. The data will be analyzed in modified intention to treat.

DISCUSSION

This trial will evaluate the effect of remimazolam on the development of POD compared to propofol anesthesia. The results of this trial will provide evidence regarding the choice of optimal anesthetics to minimize the risk of POD in neurosurgical patients.

TRIAL REGISTRATION

The study protocol was prospectively registered at the Clinical trials ( https://clinicaltrials.gov , NCT06115031, principal investigator: Jiseon Jeong; date of first registration: November 2, 2023, before the recruitment of the first participant.

Anaesthetic efficacy and postinduction hypotension with remimazolam compared with propofol: a multicentre randomised controlled trial

Remimazolam, a short-acting benzodiazepine, may be used for induction and maintenance of total intravenous anaesthesia, but its role in the management of patients with multiple comorbidities remains unclear. In this phase 3 randomised controlled trial, we compared the anaesthetic efficacy and the incidence of postinduction hypotension during total intravenous anaesthesia with remimazolam vs. propofol. A total of 365 patients (ASA physical status 3 or 4) scheduled for elective surgery were assigned randomly to receive total intravenous anaesthesia with remimazolam (n = 270) or propofol (n = 95). Primary outcome was anaesthetic effect, quantified as the percentage of time with Narcotrend® Index values ≤ 60, during surgery (skin incision to last skin suture), with a non-inferiority margin of -10%. Secondary outcome was the incidence of postinduction hypotensive events. Mean (SD) percentage of time with Narcotrend Index values ≤ 60 during surgery across all patients receiving remimazolam (93% (20.7)) was non-inferior to propofol (99% (4.2)), mean difference (97.5%CI) -6.28% (-8.89-infinite); p = 0.003. Mean (SD) number of postinduction hypotension events was 62 (38.1) and 71 (41.1) for patients allocated to the remimazolam and propofol groups, respectively; p = 0.015. Noradrenaline administration events (requirement for a bolus and/or infusion) were also lower in patients allocated to remimazolam compared with propofol (14 (13.5) vs. 20 (14.6), respectively; p < 0.001). In conclusion, in patients who were ASA physical status 3 or 4, the anaesthetic effect of remimazolam was non-inferior to propofol.

Preliminary Experience With Remimazolam for Procedural Sedation and as an Adjunct to General Anesthesia During Diagnostic and Interventional Cardiac Procedures

Background

Remimazolam is a benzodiazepine which, like midazolam, has sedative, anxiolytic, and amnestic properties. Ester metabolism results in a half-life of 5 - 10 min, a limited context sensitive half-life, and rapid recovery when the infusion is discontinued.

Methods

Following the Institutional Review Board (IRB) approval, we performed a retrospective chart review of patients who received remimazolam in the cardiac catheterization, cardiac magnetic resonance imaging (MRI), and electrophysiology suites. The primary objective was to assess efficacy and safety. The secondary objective was to describe bolus and infusion dosing of remimazolam and the need for adjunctive agents to optimize procedural sedation conditions.

Results

The study cohort included 26 patients with a median age of 18 years and a total of 33 anesthetic encounters. The most common procedures were endomyocardial biopsy or isolated hemodynamic assessment (right or left heart catheterization). Remimazolam was the primary agent for sedation in 82% of the procedures. The majority of cases (25 encounters, 76%) included a bolus dose of remimazolam prior to the start of an infusion. For those patients who received a starting bolus dose, dosing typically ranged between 30 and 110 µg/kg. Continuous infusion rates of remimazolam varied from 5 to 20 µg/kg/min. No adverse hemodynamic or respiratory effects were noted. Midazolam, fentanyl, and dexmedetomidine were the most frequently used adjunctive agents. One patient required transition to general anesthesia due to the need for a surgical intervention based on the findings of the cardiac catheterization. All other patients were effectively sedated.

Conclusions

Our preliminary experience demonstrates that remimazolam effectively provided sedation for diagnostic and therapeutic cardiovascular procedures. Future studies are needed to further define dosing parameters for both bolus dosing and continuous infusion as well as to compare remimazolam to other commonly used for procedural sedation in patients with congenital and acquired heart disease.

The Role of Remimazolam in Neurosurgery and in Patients With Neurological Diseases: A Narrative Review

Remimazolam is a novel ultrashort-acting benzodiazepine that produces sedation by acting as a positive allosteric modulator of the gamma-amino butyric acid-A receptor. Its high water solubility and metabolism via tissue esterases allow for a rapid onset of sedation/anesthesia and prompt arousal despite prolonged use. In addition, the effects of remimazolam can be reversed with flumazenil. This narrative review discusses the role of remimazolam in patients undergoing neurosurgical and neuroradiological procedures, specifically its role during awake craniotomies and compatibility with neuromonitoring. Considerations for remimazolam use in patients with neurological diseases are also highlighted. In addition, the impact of remimazolam on postoperative excitation, risk for postoperative delirium, and delayed neurocognitive recovery are discussed. Although there seems to be a clinical promise for remimazolam based on limited case studies and our own institutional experience of its use, further clinical investigation is warranted to understand the potential impact of remimazolam on surgical and neurological outcomes.

Remimazolam Anaphylaxis during Induction of General Anesthesia Confirmed by Provocation Test-A Case Report and Literature Review

Background: Remimazolam besylate, a newly developed drug, is linked to various anaphylaxis cases. We present a case of remimazolam anaphylaxis confirmed using a provocation test. Case: A 51-year-old female patient was scheduled for humeral pinning. General anesthesia was induced using remimazolam, rocuronium, and remifentanil. After tracheal intubation, the patient experienced decreased blood pressure, increased heart rate, and a systemic rash. Epinephrine was administered repeatedly, and the patient's vital signs stabilized. Acute phase tryptase levels were within normal limits. After four weeks, intradermal test results were negative. When remimazolam was administered intravenously for the provocation test, facial swelling, flushing, and coughing occurred, which improved with epinephrine. The culprit drug was identified as remimazolam using a provocation test. Conclusions: When anaphylaxis occurs during anesthesia induction, remimazolam should not be ruled out as the causative drug. If the skin test result for remimazolam is negative, a provocation test should be considered. The provocation test should be initiated cautiously at a low dose under careful patient monitoring.

Comparison of the Incidence of Postoperative Acute Kidney Injury Following the Administration of Remimazolam or Sevoflurane in Elderly Patients Undergoing Total Knee Arthroplasty: A Randomized Controlled Trial

BACKGROUND

We evaluated the incidence of postoperative acute kidney injury (AKI) and complications when remimazolam (RMMZ) or sevoflurane (SEVO) were used in elderly patients undergoing total knee arthroplasty.

METHODS

Seventy-eight participants aged ≥65 were randomly allocated to either the RMMZ or SEVO group. The primary outcome was the incidence of AKI on postoperative day (POD) 2. The secondary outcomes included intraoperative heart rate (HR), blood pressure (BP), total drug administered, emergence time, postoperative complications on POD 2, and hospital length of stay (HLOS).

RESULTS

The incidence of AKI was comparable between the RMMZ and SEVO groups. The doses of intraoperative remifentanil, vasodilators, and additional sedatives were significantly higher in the RMMZ group than in the SEVO group. Overall intraoperative HR and BP tended to remain higher in the RMMZ group. The emergence time in the operating room was significantly faster in the RMMZ group; however, the time required for an Aldrete score ≥ 9 was comparable between the RMMZ and SEVO groups. Postoperative complications and HLOS were comparable between the RMMZ and SEVO groups.

CONCLUSION

RMMZ may be recommended for patients who are expected to decrease in intraoperative vital signs. However, stable hemodynamics with RMMZ were not sufficient to influence the prevention of AKI.