Using Etomidate and Midazolam for Screening Colonoscopies Results in More Stable Hemodynamic Responses in Patients of All Ages

Optimizing sedation in gastroscopy: a study on the etomidate/propofol mixture ratio

Objective

Propofol and etomidate are the most commonly used sedative agents in procedural sedation, each with its own advantages and disadvantages. However, there remains considerable controversy regarding the optimal ratio for the mixture of these two drugs, warranting further investigation. Therefore, this study aims to investigate the optimal ratio for combining propofol and etomidate during gastroscopy.

Methods

This study is a prospective, double-blinded, randomized controlled clinical trial. One hundred and sixty-two patients from July 2019 to December 2022 were evenly classified into three groups using a random number table as follows: (1) P group (propofol); (2) EP1 group (5 mL etomidate +10 mL propofol); (3) EP2 group (10 mL etomidate +10 mL), 54 patients per group. The medications, including a pre-sedation dose of 50 μg/kg dezocine followed by sedatives, ceasing when the patient's eyelash reflex vanished, indicating adequate sedation. Mean arterial pressure (MAP), heart rate (HR), and peripheral oxygen saturation (SpO2) measurements taken before anesthesia (T1), immediately after the administration of sedatives (T2), immediately gastroscopic insertion (T3) and immediately recovery (T4) were determined. Additional, perioperative related outcomes and adverse events were also recorded.

Results

The EP2 group exhibited a higher MAP at T2 compared to the P and EP1 groups (p < 0.05). Calculated decreases in MAP revealed values of 19.1, 18.8, and 13.8% for the P, EP1, and EP2 groups at T2, respectively. Adverse events: Group EP2 exhibited a significantly lower hypotension incidence (11.1%) compared to the Propofol group (50%) and EP1 (31.5%). Concerning injection pain, Group EP2 also showing a significant decrease in comparison to P and EP1 groups (p < 0.05).

Conclusion

The use of a mixture of 10 mL etomidate and 10 mL propofol (at a 1:1 ratio) combined with dezocine for painless gastroscopy demonstrates hemodynamic stability, a low incidence of adverse reactions.

Clinical Trial Registration

https://www.chictr.org.cn/showproj.html?proj=39874.

The need to monitor emerging issues in etomidate usage: the misuse or abuse potential

Since 2011, the misuse or abuse of etomidate has gradually increased when propofol was designated a controlled drug under the Narcotics Control Act in Korea. Accordingly, the Ministry of Food and Drug Safety announced that etomidate would be under the 'Regulation on the designation of drugs that may cause concerns of misuse or abuse' rule in June 2020, which is less stringent than the Narcotics Control Act. Therefore, this review investigates potential misuse or abuse cases of etomidate to consider strengthening its management. A literature search was conducted to compare etomidate with other sedatives in their efficacy and side effects, as well as identify the adverse health outcomes, abuse cases, and analytical methods of etomidate. Etomidate has an equal or higher sedative efficacy and lower risk of adverse cardiopulmonary events than propofol. However, major adverse effects of etomidate include adrenocortical suppression and unproven associated deaths, as well as myoclonus requiring pre-treatment. Although the issue of abuse and misuse of etomidate is emerging in recent years, there are few academic reports on these issues and analytical methods in the forensic field. In order to effectively manage the misuse or abuse of etomidate, it is necessary to continuously monitor related cases with great interest and to be more intensively studied on its abuse potential.

Effects of dexmedetomidine combined with etomidate on postoperative cognitive function in older patients undergoing total intravenous anaesthesia: a randomized, double-blind, controlled trial

BACKGROUND

Etomidate has been advocated for anesthesia in older and critically ill patients because of its hemodynamic stability. Clinical studies have shown that dexmedetomidine has neuroprotective and anti-inflammatory properties and improves postoperative cognitive dysfunction in older patients. The present study was to evaluate the effects of the combination of etomidate and dexmedetomidine with different anaesthesia time on postoperative cognitive function in older patients.

METHODS

A total of 132 older patients undergoing ureteroscopic holmium laser lithotripsy were randomly divided into EN group and ED group equally. Patients whose surgery time was less than or equal to 1 h in each group were allocated to short-time surgery group (EN1 group and ED1 group), and whose surgery time was more than 1h were allocated to long-term surgery group (EN2 group and ED2 group). The primary outcome was the score of the Mini-Mental State Examination. The secondary outcomes were State-Trait Anxiety Inventory scores, Riker sedation agitation scores, Zung Self-Rating Depression Scale scores, the memory span for Arabic numerals, the plasma concentrations of S-100 calcium-binding protein B and neuron specific enolase, the time to spontaneous respiration, recovery, and extubation.

RESULTS

The MMSE scores at t2-3 were higher in ED1 and ED2 groups than in EN1 and EN2 groups (p<0.05). Compared with ED1 and ED2 groups, the ZSDS scores, the S-AI scores and the T-AI scores at t1-2 were higher in EN1 and EN2 groups (p<0.05), respectively. The recalled Arabic numbers at t1-3 were higher in ED2 group than in EN2 group (p<0.05). The plasma concentration of S-100β at t1-2 in EN1 group and t1-3 in EN2 group were higher than that in ED1 and ED2 groups (p<0.05), respectively. Compared with ED1 and ED2 groups, the plasma concentrations of NSE were higher at t1-3 in EN1 group and t1-4 in EN2 group (p<0.05), respectively.

CONCLUSION

The administration of dexmedetomidine could improve postoperative cognitive dysfunction, emergence agitation, depression and anxiety, attenuate the plasma concentrations of S-100β and NSE in older patients undergoing total intravenous anaesthesia with etomidate.

TRIAL REGISTRATION

Registration number: ChiCTR1800015421, Date: 29/03/2018.

Etomidate versus propofol for sedation in gastrointestinal endoscopy: A systematic review and meta-analysis of outcomes

BACKGROUND

Propofol is increasingly being used for sedation in gastrointestinal endoscopy; however, owing to its side effects, an alternative drug is needed. We aimed to compare the safety, satisfaction, and efficacy outcomes of etomidate versus propofol in patients undergoing gastrointestinal endoscopy, including advanced endoscopic procedures.

METHODS

We systematically searched Embase, PubMed, Cochrane Central Register of Controlled Trials, CINAHL (via EBSCO), China National Knowledge Infrastructure, and Web of Science (1946-April 2020) databases for randomized controlled trials of gastrointestinal endoscopy (upper gastrointestinal endoscopy, colonoscopy, and advanced endoscopy) using etomidate or propofol as sedatives. We pooled odds ratios (ORs) for the safety profile and patient and anesthesiologist satisfaction using mixed-effects conditional logistic models and standardized mean differences for efficiency outcomes using random-effects models.

RESULTS

Twenty-four studies involving 3875 patients were included. Compared with propofol, etomidate resulted in significantly reduced apnea (OR: 0.22; 95% confidence interval [CI]: 0.13-0.37; P < .001), hypoxemia (OR: 0.43; 95% CI: 0.35-0.54; P < .001), hypotension (OR: 0.20; 95% CI: 0.11-0.36; P < .001), and bradycardia (OR: 0.52; 95% CI: 0.30-0.91; P = .02) but led to increased myoclonus (OR: 8.54; 95% CI: 5.20-14.01; P < .001) and lowered anesthesiologist satisfaction (OR: 0.60; 95% CI: 0.39-0.91; P = .02).

CONCLUSION

Etomidate may be a good alternative to propofol for gastrointestinal endoscopy, especially advanced endoscopy. Etomidate appears to be safe as an inducer for hemodynamically unstable patients or older adult patients undergoing gastrointestinal endoscopy.

Discharge readiness after remimazolam versus propofol for colonoscopy: A randomised, double-blind trial

BACKGROUND

Remimazolam is an ultrashort-acting benzodiazepine that is potentially a practical option for procedural sedation in colonoscopy.

OBJECTIVE

To test the hypothesis that remimazolam could provide a noninferior discharge time to propofol for ambulatory colonoscopy.

DESIGN

A prospective, randomised, double-blind, noninferiority clinical trial.

SETTING

Ambulatory endoscopy centre.

PATIENTS

A total of 132 adult participants undergoing ambulatory colonoscopy were enrolled.

INTERVENTIONS

Participants were randomly assigned in a 1 : 1 ratio to receive propofol or remimazolam for sedation.

MAIN OUTCOME MEASURES

The primary outcome was discharge time after a colonoscopy, assessed using the Modified Postanaesthetic Discharge Scoring System scale. Secondary outcomes included induction time, emergence time, the extent of recovery upon arrival in the postanaethesia care unit, fatigue, endoscopist and patient satisfaction and adverse events.

RESULTS

The median discharge time was 24 min in the remimazolam group versus 21 min in the propofol group, with a difference of 2 min [95% confidence interval (CI), 0 to 4 min], meeting the criteria for noninferiority. Injection pain occurred in 11 of 66 (17%) participants receiving remimazolam versus 32 of 66 (49%) participants receiving propofol ( P  < 0.001); hypotension occurrence was 20% versus 47%, ( P  < 0.001), respectively, and bradycardia 6% versus 20%, ( P  = 0.019), respectively. Compared with propofol, the patient satisfaction score was higher in the remimazolam group ( P  < 0.001).

CONCLUSION

For sedation in ambulatory colonoscopy, compared with propofol, remimazolam provides a noninferior discharge time. Furthermore, remimazolam is associated with less injection pain, lower risks of hypotension and bradycardia, and improved patient satisfaction.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, identifier: ChiCTR2100048678.

Intravenous anesthesia with different doses of propofol combined with etomidate for painless colonoscopy in elderly obese patients: Effectiveness and impact on neurocognitive disorders

BACKGROUND

Painless colonoscopy in elderly obese patients is an invasive examination and requires good anesthesia and analgesia. Intravenous anesthesia with propofol combined with etomidate has good analgesic and sedative effects. However, there is no uniform standard for propofol dosage.

AIM

To investigate the effectiveness of intravenous anesthesia with different doses of propofol compounded with etomidate for painless colonoscopy in elderly obese patients and the effect on neurocognitive disorders.

METHODS

One hundred and twelve elderly obese patients who underwent painless colonoscopy at our hospital from January 2021 to March 2022 were selected and divided into either a control group or a study group (56 patients each) according to the odd-even nature of admission serial number. The control group (odd serial number) underwent intravenous anesthesia with a regular dose of propofol and etomidate for intravenous anesthesia, and the study group (even serial number) was given a small dose of propofol with etomidate for intravenous anesthesia. The anesthetic effect, time of colonoscopy, heart rate (HR) at different time points in the perioperative period, mean arterial pressure (MAP), incidence of adverse effects, use of anesthetic drugs, and cognitive function (Mini-mental State Examination [MMSE] score) before and after surgery were compared between the two groups.

RESULTS

There was no statistically significant difference in the onset of anesthesia, anesthesiologist's satisfaction with anesthesia, or colonoscopy time between the two groups, and the time to awakening and post-awakening observation room stay were significantly shorter in the study group than in the control group (P < 0.05). HR and MAP at T1 and T2 were lower than those at T0 in both groups (P < 0.05), and HR and MAP at all time points did not differ significantly between the two groups (P > 0.05). The dosage of propofol in the study group was significantly less than that of the control group (P < 0.05), though the dosage of etomidate and the number of propofol additions were not significantly different between the two groups. The incidence of adverse reactions in the study group (8.93%) was significantly lower than that in the control group (23.21%; P < 0.05). The postoperative 1-h MMSE score was lower than the preoperative score in both groups, but it was significantly higher in the study group than in the control group (P < 0.05).

CONCLUSION

The use of intravenous anesthesia with low-dose propofol with etomidate in painless colonoscopy in elderly obese patients can ensure the effectiveness of anesthesia, improve the quality of postoperative awakening, reduce adverse effects, and mitigate the impact on cognitive function.

Etomidate affects spatial learning and memory and neuronal apoptosis of rats via MAPK/ERK pathway

OBJECTIVE

To observe the effect of etomidate on spatial learning and memory and neuronal apoptosis in rats of different ages.

METHODS

The rats of different ages were divided into 3 age groups: juvenile (21-day old), adult (~3-months old) and elderly (~19-months old). Then, rats with similar age within a group were randomly divided into three subgroups, with 10 rats in each group. The experimental subgroups were intraperitoneally injected with etomidate (emulsion formulated, i.p. injection) at a dose of 5 mg/kg; the solvent control subgroups were given intraperitoneal injection of vehicle emulsion; and blank control subgroups received laparoscopic injection of normal saline. The rats' learning and memory ability was tested by Morris water maze. The tissue sections of each group's hippocampus were analyzed by H&E staining. The apoptosis of hippocampal cells was detected by TUNEL staining. MAPK expression in hippocampus was tested by Western blot.

RESULTS

Etomidate significantly extended the escape latency and reduced the platform crossings and the swimming time at original platform of juvenile rats, indicating that the spatial learning and memory function of juvenile rats can be affected by etomidate. However, etomidate had no effect on spatial learning and memory in adult and elderly rats. There were no obvious abnormalities in number of neurons and morphology of vertebral cells in the hippocampus of all experimental subgroups when compared with those of corresponding blank control subgroups. There was no statistically significant difference in apoptosis index of the hippocampal tissue between the experimental subgroups and corresponding blank control subgroups (P>0.05). Within juvenile group, the expression of p-ERK in the hippocampus of experimental subgroup was remarkably lower than that of solvent control subgroup and blank control subgroup (P<0.05), while there were no significant differences in p-p38 and p-JNK expressions among the three subgroups of juvenile rats (P>0.05). The expressions of p-ERK, p-p38 and p-JNK in adult and elderly rats were not affected by etomidate.

CONCLUSION

Etomidate may have certain effects on spatial learning and memory in juvenile rats but not in adult and elderly rats. Etomidate affects neither the number of neurons in the CA1 area of the hippocampus nor the morphology of vertebral cells and did not cause the apoptosis of nerve cells. The mechanism of etomidate influence on the spatial learning and memory function of young rats may connect with the inhibition of MAPK/ERK pathway.

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.

Comparison of the Effectiveness of Various Drug Interventions to Prevent Etomidate-Induced Myoclonus: A Bayesian Network Meta-Analysis

Background

Myoclonic movement is a very common but undesirable phenomenon during the induction of general anesthesia using etomidate. Such movement may cause unnecessary problems. Currently, there is an increasing number of drugs for preventing etomidate-induced myoclonus (EM). However, direct comparisons of various drugs are lacking, and this interferes with clinical decision-making. Our network meta-analysis (NMA) aimed to compare the efficacy of different drugs for the prevention of moderate-to-severe general myoclonus.

Methods

Using several biomedical databases, randomized controlled trials (RCTs) published in English from inception to August 22, 2021 were searched. Among the various interventions, we selected nine types of intervention drugs (dexmedetomidine, etomidate, lidocaine, NMDA receptor antagonist, κ opioid receptor agonist, μ opioid receptor agonist, muscle relaxant, gabapentin, and midazolam) for comparison, according to the number of studies. Bayesian NMA was performed using STATA16 and R softwares. The relative risk of EM was assessed using risk ratios (RRs) and the corresponding 95% confidence intervals (CI).

Results

A total of 31 RCTs (3209 patients) were included. NMA results showed that, compared with a placebo, etomidate (RR 4.0, 95%CI 2.1–7.8), κ opioid receptor agonist (RR 2.9, 95%CI 1.9–4.6), μ opioid receptor agonist (RR 3.1, 95%CI 2.3–4.3), NMDA receptor antagonist (RR 1.7, 95%CI 1.0–2.8), dexmedetomidine (RR 2.4, 95%CI 1.5–3.9), lidocaine (RR 2.1, 95%CI 1.2–3.9), and midazolam (RR 2.2, 95%CI 1.5–3.2) can significantly reduce the risk of EM. In contrast, the effects of muscle relaxants (RR 2.1, 95%CI 0.81–5.3) and gabapentin (RR 2.8, 95%CI 0.92–9.3) were inconclusive. Further subgroup analyses showed that preoperative low-dose etomidate, μ-opioid receptor agonist, and κ-opioid receptor agonist were significantly better than other interventions in the prevention of moderate to severe EM.

Conclusion

Preoperative use of small doses of etomidate or opioids may be the most effective way to avoid EM, especially moderate and severe EM, which makes anesthesia induction safer, more stable, and aligns better with the requirements of comfortable medicine.

Systematic Review Registration

[https://www.crd.york.ac.uk/prospero/], [CRD4202127706].

Hypotension during propofol sedation for colonoscopy: an exploratory analysis

BACKGROUND

Intraoperative and postoperative hypotension occur commonly and are associated with organ injury and poor outcomes. Changes in arterial blood pressure (BP) during procedural sedation are not well described.

METHODS

Individual patient data from five trials of propofol sedation for colonoscopy and a clinical database were pooled and explored with logistic and linear regression. A literature search and focused meta-analysis compared the incidence of hypotension with propofol and alternative forms of procedural sedation. Hypotensive episodes were characterised by the original authors' definitions (typically systolic BP <90 mm Hg).

RESULTS

In pooled individual patient data (n=939), 36% of procedures were associated with episodes of hypotension. Longer periods of propofol sedation and larger propofol doses were associated with longer-lasting and more-profound hypotension. Amongst 380 patients for whom individual BP measurements were available, 107 (28%) experienced systolic BP <90 mm Hg for >5 min, and in 89 (23%) the episodes exceeded 10 min. Meta-analysis of 18 RCTs identified an increased risk ratio for the development of hypotension in procedures where propofol was used compared with the use of etomidate (two studies; n=260; risk ratio [RR] 2.0 [95% confidence interval: 1.37-2.92]; P=0.0003), remimazolam (one study; n=384; RR 2.15 [1.61-2.87]; P=0.0001), midazolam (14 studies; n=2218; RR 1.46 [1.18-1.79]; P=0.0004), or all benzodiazepines (15 studies; n=2602; 1.67 [1.41-1.98]; P<0.00001). Hypotension was less likely with propofol than with dexmedetomidine (one study; n=60; RR 0.24 [0.09-0.62]; P=0.003).

CONCLUSIONS

Hypotension is common during propofol sedation for colonoscopy and of a magnitude and duration associated with harm in surgical patients.

Application of etomidate and propofol mixture in hematoma removal in patients with intracranial epidural hematoma

OBJECTIVE

To innvestigate the application of etomidate and propofol mixture in the evacuation of hematoma in patients with epidural hematoma.

METHODS

98 patients with epidural hematoma were randomly divided into two groups: the joint group (n=49, anesthesia induction with etomidate and propofol) and the etomidate group (n=49, anesthesia induction with etomidate) using a random number table. Hemodynamics, stress response and cerebral oxygen metabolism were compared between the two groups at T0 (pre-anesthesia induction), T1 (after endotracheal intubation), T2 (10 min after the beginning of the operation) and T3 (the end of the operation). Adverse reactions were also analyzed.

RESULTS

Compared with T0, the mean arterial pressure (MAP) at T1, T2 and T3 in the joint group decreased first and then increased, and the MAP at T1 was significantly lower than that in the etomidate group (P<0.05). Compared with T0, blood oxygen saturation of internal jugular vein bulb (SjvO₂) increased in T1-T3 groups, and SjvO₂ in the joint group was higher than that in the etomidate group (all P<0.05). Compared with T0, cerebral oxygen uptake rate (CERO₂) in the T1-T3 groups decreased significantly, and CERO₂ at T3 in the joint group was higher than that in the etomidate group (all P<0.05). Compared with T0, the levels of cortisol and superoxide dismutase (SOD) at T3 in the two groups were significantly lower, but those in the etomidate group were higher than those in the combination group (all P<0.05). There was no significant difference in the incidence of postoperative anesthesia-related adverse reactions between the two groups (P>0.05).

CONCLUSION

Etomidate has less effect on hemodynamics and stress reaction during intravenous anesthesia, but its combination with propofol can improve cerebral oxygen metabolism to a certain extent with fewer adverse reactions.

Discovery of the EL-0052 as a potential anesthetic drug

As a γ-aminobutyric acid A receptor (GABA_AR) inhibitor, etomidate fulfills several characteristics of an ideal anesthetic agent, such as rapid onset with rapid clearance and high potency, along with cardiovascular stability. Unfortunately, etomidate has been reported to inhibit CYP11B1 at hypnotic doses, which is associated with a marked increase in patient deaths due to this unexpected off-target effect. In this study, molecular docking was used to simulate the binding mode of etomidate with GABA_AR and CYP11B1. Based on the in-depth analysis of the binding mode, strong electron-withdrawing group on the C4 position of the imidazole ring was introduced to reduce the charge density of the nitrogen, which is beneficial in reducing the coordination bond between the imidazole nitrogen and heme iron in CYP11B1, as well as in reducing the adrenocortical suppression. Based on the results of ADMET property prediction, MEP analysis, and molecular docking simulation, 4-fluoroetomidate (EL-0052) was designed and synthesized. In vivo studies in rats and mice confirmed that EL-0052 had the efficacy similar to etomidate, but without adrenocortical suppression. These findings suggested that EL-0052 was superior to etomidate and support the continued development of EL-0052 as a preclinical candidate as an anesthetic.