Relationship Between Remimazolam and Etomidate in Induction of General Anesthesia

The Interaction Between Remimazolam and Etomidate During Induction of General Anesthesia Was Studied by Isoradiometric Analysis

In modern anesthesia practice, anesthesiologists often need to choose a combination of multiple drugs according to the specific conditions and surgical needs of patients, which can not only achieve more fine anesthesia management, but also improve perioperative safety and patient comfort. In clinical practice, anesthesiologists will use etomidate combined with a small dose of remimazolam for anesthesia induction to obtain more stable hemodynamics, prevent intraoperative awareness, and relieve anxiety.However, what is the best dose ratio of etomidate combined with remimazolam, the current literature does not give clear indicators.

Study Overview

• Status: Not yet recruiting
• Conditions: Drug Interactions; Induction Anesthesia
• Intervention / Treatment: Drug: Etomidate; Drug: Remimazolam; Drug: Remimazolam-etomidate

Detailed Description

The experiment was divided into two steps. Step 1: Patients were randomly divided into group A (remimazolam induction group) and group B (etomidate induction group) according to the random number table, and group A was selected according to the literature. In group B, the initial dose was 0.2mg/kg, and 0.120mg/kg, and the ratio of successive doses was 1:0.8 and 1: 0.6, the ED50 of group A and group B was calculated by the sequential method, and the calculated remimazolam and etomidate were used as the initial doses of subgroups Step 2: According to the random number table, the patients were divided into group C (0.25ED50 remimazolam +0.75ED50 etomidate), group D (0.5ED50 remimazolam +0.50ED50 etomidate), group E (0.75ED50 remimazolam +0.25ED50 etomidate), and the dose of remimazolam in each group was fixed. The ED50 of etomidate in group C, group D and group E were calculated by sequential method.

Anesthesia methods: One hundred and twenty-five patients of both sexes, aged 18-60 yr, of American Society of Anesthesiologists physical status I-II, BIM: 18-30kg/m2, undergoing general anesthesia in the Second Hospital of Shanxi Medical University, were selected. Before operation, the patients were required to fast and drink, and had not received special preoperative medication. After the patient entered the room, blood pressure, heart rate, oxygen saturation and BIS were monitored and oxygen inhalation was given to the mask for 5L/min. After the tripartite verification was correct, intravenous access was established in the patient's upper limb, fluid infusion was opened, anesthesia was induced, remimazolam and etomidate were injected directly and slowly intravenously, and remimazolam and etomidate were injected for more than 10s according to the dosage of each group. Two drugs were injected at an interval of 10s or more. After the completion of one drug injection, 5ml normal saline was used to flush the tube, and the score was scored 2 minutes after intravenous injection. BIS value of 45-60 was considered as a positive response, and the dose gradient of the next patient was reduced. The observation was calculated as the first patient with positive to negative turning point, and the observation ended when the next patient with positive to negative reaction at the seventh turning point. The secondary outcome measures were the incidence of adverse reactions, changes in heart rate and blood pressure. At the end of the observation, if the patient showed a negative reaction, 0.08mg/kg etomidate was added for sedation, and then sufentanil and rocuronium were given for tracheal intubation in turn, and then surgery was performed.The demographic data of the patients were collected, including: gender, age, height, weight, BIM Statistical methods: probit model was used to calculate ED50 of each group, and the drug correlation coefficient was introduced as 1/(actual dose of remimazolam/ED50 of remimazolam + actual dose of etomidate/ED50 of etomidate). The measurement data with normal distribution were expressed as mean ± standard deviation (x±s). The measurement data with normal distribution between group A and group B were compared by two independent sample t test, and the comparison between group C, group D and group E was compared by one-way analysis of variance. Graphpad prism software was used to make five groups of sequential experimental plots and iso-radiation analysis plots when P<0.05 was considered statistically significant.

• Study Type: Interventional
• Enrollment (Estimated): 125
• Phase: Early Phase 1

Contacts and Locations

Study Locations

• China
  • Shanxi
    • Taiyuan, Shanxi, China, 030001
      • Second Hospital of Shanxi Medical University
      • Contact: Zheng Guo M.B.,Ph.D.; Phone Number: +863513365790; Email: guozheng713@yahoo.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Both sexes
2. aged 18-60 yr
3. ASA physical status I-II
4. BIM: 18-28kg/m²

Exclusion Criteria:

1. allergic to remimazolam and etomidate
2. in pregnancy or lactation
3. serious cardiovascular diseases, long-term alcoholism
4. used sedative drugs or opioids within 24 hours
5. severe mental illness and myasthenia gravis -

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Group A (remimazolam induction group); The ED50 of group A was calculated by sequential method	Drug: Etomidate; Group A was induced with etomidate, the initial dose was 0.120mg/kg, and the ratio of adjacent doses was 1:0.6
Experimental: Group B (etomidate induction group); The ED50 of group B was calculated by sequential method	Drug: Remimazolam; Group B was induced with remimazolam, the initial dose was 0.20mg/kg, and the ratio of adjacent doses was 1:0.8
Experimental: group C (0.25ED50 remimazolam +0.75ED50 etomidate); The ED50 of etomidate in group C were calculated by sequential method.	Drug: Remimazolam-etomidate; In group C, 0.25ED50 remimazolam +0.75ED50 etomidate was used as the initial measurement In group D, 0.5ED50 remimazolam +0.5ED50 etomidate was used as the initial measurement In group E, 0.75ED50 of remimazolam +0.25ED50 of etomidate was used as the initial measurement
Experimental: Group D (0.5ED50 remimazolam +0.5ED50 etomidate); The ED50 of etomidate in group Dwere calculated by sequential method.	Drug: Remimazolam-etomidate; In group C, 0.25ED50 remimazolam +0.75ED50 etomidate was used as the initial measurement In group D, 0.5ED50 remimazolam +0.5ED50 etomidate was used as the initial measurement In group E, 0.75ED50 of remimazolam +0.25ED50 of etomidate was used as the initial measurement
Experimental: Group E (0.75ED50 remimazolam +0.25 etomidate); The ED50 of etomidate in group E were calculated by sequential method.	Drug: Remimazolam-etomidate; In group C, 0.25ED50 remimazolam +0.75ED50 etomidate was used as the initial measurement In group D, 0.5ED50 remimazolam +0.5ED50 etomidate was used as the initial measurement In group E, 0.75ED50 of remimazolam +0.25ED50 of etomidate was used as the initial measurement

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The ED50 value of etomidate in Group A	The sequential method was used to calculate the median effective dose of etomidate in group A. When the patient's BIS value was between 45 and 60, it was considered a positive response. For the next patient, the dose was reduced by one dose gradient; conversely, if it was a negative response, the dose was increased by one dose gradient. The observation was stopped when the first patient reached the positive-negative turning point, and the next patient with the positive-negative reaction was reached for the seventh turning point. The ED50 of each group was calculated using the probit model.	one week
The ED50 value of Remimazolam in Group B	The sequential method was used to calculate the median effective dose of remimazolam in group B. A positive reaction was defined as a patient's BIS value ranging from 45 to 60. For the next patient, the dose was reduced by one dose gradient if it was a positive reaction, and increased by one dose gradient if it was a negative reaction. The observation was stopped when the next patient with the 7th positive-negative reaction point was reached. The ED50 of each group was calculated using the probit model.	one week
Group C D E: etomidate ED50	The sequential method was adopted to calculate the median effective dose of etomidate for groups C, D, and E separately. A patient was considered to have a positive response if their BIS value was between 45 and 60. For the next patient, the dose was reduced by one dose gradient if it was a positive response, and increased by one dose gradient if it was a negative response. The observation was ended when the next patient with the 7th positive-negative response was reached. The ED50 of each group was calculated using the probit model.	three weeks
Isoradiation pattern	The ED50 determined for groups A and B was plotted on the isoradiogram. The ED50 of etomidate and its 95% confidence interval were plotted on the horizontal axis, and the ED50 of remimazolam and its 95% confidence interval were plotted on the vertical axis. The two ED50 were connected to form an additive line, and the confidence interval was connected to form an additive line with 95% confidence interval. When the two drugs were used together, the effect intensity of the compound drugs fell on the additive line (or within the confidence interval), indicating that the two drugs had additive effect. On the left side of the addition line and confidence interval, it indicated that the two drugs had synergistic effect. If it falls on the right side, it is antagonistic.	24 hours
drug correlation coefficient	The drug correlation coefficient = 1/(actual dose of remimazolam/ED50 of remimazolam + actual dose of etomidate/ED50 of etomidate).	24 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
muscle tremor	Side effects of etomidate	5 weeks
Bradycardia	The heart rate was less than 45 beats per minute	5 weeks
hypotension	Blood pressure is lower than the baseline by 20%.	5 weeks

Collaborators and Investigators

• Sponsor: Second Hospital of Shanxi Medical University

Study record dates

Study Major Dates

• Study Start (Estimated): June 12, 2025
• Primary Completion (Estimated): June 19, 2025
• Study Completion (Estimated): July 19, 2025

Study Registration Dates

• First Submitted: May 19, 2025
• First Submitted That Met QC Criteria: June 8, 2025
• First Posted (Actual): June 10, 2025

Study Record Updates

• Last Update Posted (Actual): June 10, 2025
• Last Update Submitted That Met QC Criteria: June 8, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: etomidate; remimazolam; Isoradiation analysis
• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Anesthetics; Central Nervous System Depressants; Hypnotics and Sedatives; Anesthetics, Intravenous; Anesthetics, General; Etomidate
• Other Study ID Numbers: yuewei20250519

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No