Median Effective Dose of Remimazolam for Sedation in Elderly Patients

Median Effective Dose of Remimazolam for Sedation in Elderly Patients Undergoing Lower Limb Surgery Under Spinal Anesthesia

Currently used drugs for monitored general anesthesia include propofol, midazolam, and dexmedetomidine. Each drug has different advantages and disadvantages. Remimazolam causes a relatively small decrease in blood pressure, and it has no injection pain. In addition, remimazolam has a very short onset time, and even after the continuous infusion, the onset of remimazolam is fast, and even after continuous injection, the effect disappeared very quickly due to the short context-sensitive half time. And through continuous infusion, the patient's depth of anesthesia can be maintained constant. In addition, the short duration of action and the ability to quickly reverse the effect of flumazenil suggest that remimazolam can be used effectively under general anesthesia as well as under general anesthesia. Remimazolam can be used as a continuous infusion for general anesthesia. However, it has also been reported to be used for sedation by continuous infusion or divided intravenous infusion. However, the effective maintenance dose of remimazolam for sedation without mechanical ventilation has not been established. In addition, age might be an important factor for determining the appropriate dose of remimazolam.

In this study, we aim to identify the median effective dose of remimazolam for maintaining sedation in elderly patients undergoing lower limb surgery under spinal anesthesia.

Study Overview

• Status: Completed
• Conditions: Sedative
• Intervention / Treatment: Drug: Remimazolam

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Phase 4

Contacts and Locations

Study Locations

• Korea, Republic of
  • Seoul, Korea, Republic of, 05505
    • Asan Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 65 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• age: equal or older than 20 years
• ASA PS: 1-3
• patients who are scheduled to undergo lower limb surgery under spinal anesthesia with sedation using remimazolam

Exclusion Criteria:

• Patients who refuse to participate in this study
• Patients with hypersensitivity to benzodiazepine or flumazenil
• Patients with severe renal/hepatic disease
• Patients with drug/alcohol abuse
• Patients who take antidepressants, anticonvulsants, psychoactive drugs chronically
• Patients with difficulty in communication
• Patients with severe obstructive sleep apnea or other airway problems
• Patients contraindicated to regional anesthesia
• Patients judged to be inappropriate for this study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: old-old group; a group of patients who are equal or older than 75 years	Drug: Remimazolam; A loading dose of remimazolam is 1mg/kg/hr. When sedation is achieved, the dose of remimazolam is adjusted to the assigned dose. The maintenance dose of remimazolam begins at 1.0mg/kg/hr. When the maintenance is not successful during the surgery, the maintenance dose will be increased by 0.1-0.2mg/kg/hr in the next patient. When the maintenance is successful, the dose will be decreased by 0.1-0.2mg/kg/hr. (maximal dose: 2mg/kg/hr)
Active Comparator: young-old group; a group of patients who are 60 to 74 years old	Drug: Remimazolam; A loading dose of remimazolam is 1mg/kg/hr. When sedation is achieved, the dose of remimazolam is adjusted to the assigned dose. The maintenance dose of remimazolam begins at 1.0mg/kg/hr. When the maintenance is not successful during the surgery, the maintenance dose will be increased by 0.1-0.2mg/kg/hr in the next patient. When the maintenance is successful, the dose will be decreased by 0.1-0.2mg/kg/hr. (maximal dose: 2mg/kg/hr)
Active Comparator: young adult group; a group of patients who are 20-59 years old	Drug: Remimazolam; A loading dose of remimazolam is 1mg/kg/hr. When sedation is achieved, the dose of remimazolam is adjusted to the assigned dose. The maintenance dose of remimazolam begins at 1.0mg/kg/hr. When the maintenance is not successful during the surgery, the maintenance dose will be increased by 0.1-0.2mg/kg/hr in the next patient. When the maintenance is successful, the dose will be decreased by 0.1-0.2mg/kg/hr. (maximal dose: 2mg/kg/hr)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
success or failure of sedation maintenance	MOAA/S score of 3 or less (MOAA/S: Modified Observer's Alertness/Sedation scale) Awake (5) - Unresponsive (0)	throughout the surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
respiratory depression	respiratory rate equal or less than 6 time per minute	throughout the surgery

Collaborators and Investigators

• Sponsor: Asan Medical Center
• Investigators: Principal Investigator: Won Uk Koh, Asan Medical Center

Study record dates

Study Major Dates

• Study Start (Actual): May 10, 2022
• Primary Completion (Actual): October 28, 2022
• Study Completion (Actual): October 28, 2022

Study Registration Dates

• First Submitted: May 12, 2022
• First Submitted That Met QC Criteria: July 19, 2022
• First Posted (Actual): July 21, 2022

Study Record Updates

• Last Update Posted (Actual): April 21, 2023
• Last Update Submitted That Met QC Criteria: April 19, 2023
• Last Verified: April 1, 2023

More Information

Terms related to this study

• Other Study ID Numbers: 2021-1869

Drug and device information, study documents

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