Effects of Remimazolam on Breathing Patterns, Respiratory Drive, and Inspiratory Effort in Mechanically Ventilated Patients

November 11, 2026 updated by: Jian-Xin Zhou, Capital Medical University

Sedatives and analgesics are usually given for analgesic, anxiolytic, or sedating purposes for patients with critical illness, while they inevitably inhibit respiratory and circulatory function. Sometimes, patients receive deep sedation to induce hypoventilation or suppress spontaneous respiratory effort. The sedation level in clinical practice is usually assessed with subjective sedation scoring systems, such as the Richmond Agitation Sedation Scale (RASS). However, studies have found that sedation depth based on RASS is not a reliable marker of respiratory drive during critical illness. In recent years, researchers have proposed to monitor the effects of sedatives and analgesics on respiratory indicators and to implement lung-protective sedation, such as airway occlusion pressure (P0.1), airway occlusion pressure (Pocc). However, different pharmacological characteristics, different depths of sedation, and different sedation regimens among different sedatives and analgesics make a great difference in their effects on respiration. Remimazolam is a new benzodiazepine sedative developed by adding a methyl propionate side chain to the structure of midazolam. As an organic weak base, remimazolam forms a salt with benzenesulfonic acid, which enhances its solubility and stability. The sedative effect of remimazolam primarily occurs through binding to γ-aminobutyric acid type A (GABAA) receptors, opening chloride channels, promoting chloride ion influx, hyperpolarizing neuronal membranes, and thereby suppressing neuronal excitability. The drug acts rapidly, achieving maximum sedation within three minutes after administration. Research on adverse effects of remimazolam remains limited, particularly regarding its impact on respiratory function. Therefore, this study aims to investigate the effects of remimazolam on breathing patterns, respiratory drive, and inspiratory effort in mechanically ventilated patients.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
20

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • China
      • Beijing, China
        • Beijing Tiantan Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion criteria:

  • Patients admitted to the ICU after surgery under general anesthesia;
  • Patients with an artificial airway and receiving assisted ventilation in pressure support mode;
  • Patients expected to achieve a sedation depth corresponding to a Richmond Agitation and Sedation Scale (RASS) score of -2 to +1;

Exclusion Criteria:

  • Patients with brainstem tumors or neuromuscular disorders;
  • Patients unable to undergo RASS assessment due to various reasons, such as history of psychiatric disorders (schizophrenia, mania, delirium, cognitive impairment), status epilepticus, or coma;
  • Patients with known or suspected allergy or contraindication to any component of the study drug or opioids;
  • Severe hepatic dysfunction (Child-Pugh class C);
  • Chronic kidney disease (estimated glomerular filtration rate < 60 ml/min/1.73 m²);
  • Mean arterial pressure (MAP) < 65 mmHg, or requiring norepinephrine infusion > 0.5 μg/kg/min to maintain MAP ≥ 65 mmHg;
  • Age <18 years old;
  • Pregnant or breastfeeding women;
  • Body mass index (BMI) <18 kg/m² or >30 kg/m²

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Remimazolam

The investigators conducted a single-arm, prospective physiological trial to assess the respiratory effects of remimazolam. The study enrolled 20 patients receiving invasive mechanical ventilation. Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h. The primary outcomes were changes in breathing pattern (respiratory rate (RR), tidal volume (VT), and minute ventilation (Vmin)), respiratory drive (airway occlusion pressure (P0.1)), and inspiratory effort (pressure muscle index (PMI) and airway occlusion pressure (ΔPocc)) after 0.15 mg/kg/h infusion of remimazolam.
Drug: Remimazolam

Remimazolam will be infused at 0.15，0.175，0.20，0.225，0.25，0.275, 0.3 mg/kg/h in sequence for 30 minutes at each dose.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Tidal volume
Time Frame: At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes

The change in tidal volume 30 minutes after remimazolam was infused at a rate of 0.15mg/kg/h compared to the baseline level without the use of sedative drugs.
At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes
Respiratory rate
Time Frame: At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes

The change in respiratory rate 30 minutes after remimazolam was infused at a rate of 0.15mg/kg/h compared to the baseline level without the use of sedative drugs.
At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes
Minute ventilation
Time Frame: At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes

The change in minute ventilation 30 minutes after remimazolam was infused at a rate of 0.15mg/kg/h compared to the baseline level without the use of sedative drugs.
At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes
Airway occlusion pressure (P0.1)
Time Frame: At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes

The change in P0.1 30 minutes after remimazolam was infused at a rate of 0.15mg/kg/h compared to the baseline level without the use of sedative drugs.
At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes
Pressure muscle index (PMI)
Time Frame: At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes

The change in PMI 30 minutes after remimazolam was infused at a rate of 0.15mg/kg/h compared to the baseline level without the use of sedative drugs.
At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes
Airway occlusion pressure (Pocc)
Time Frame: At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes

The change in Pocc 30 minutes after remimazolam was infused at a rate of 0.15mg/kg/h compared to the baseline level without the use of sedative drugs.
At baseline (before sedation with remimazolam) and 0.15 mg/kg/h remimazolam continuous infusion for 30 minutes

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Respiratory rate
Time Frame: Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, respiratory rate was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)

Changing trends in respiratory rate during remimazolam infusion from 0.15 mg/kg/h to 0.3 mg/kg/h
Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, respiratory rate was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)
Tidal volume
Time Frame: Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, tidal volume was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)

Changing trends in tidal volume during remimazolam infusion from 0.15 mg/kg/h to 0.3 mg/kg/h
Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, tidal volume was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)
Minute ventilation
Time Frame: Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, minute ventilation was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)

Changing trends in minute ventilation during remimazolam infusion from 0.15 mg/kg/h to 0.3 mg/kg/h
Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, minute ventilation was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)
P0.1
Time Frame: Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, P0.1 was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)

Changing trends in P0.1 during remimazolam infusion from 0.15 mg/kg/h to 0.3 mg/kg/h
Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, P0.1 was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)
PMI
Time Frame: Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, PMI was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)

Changing trends in PMI during remimazolam infusion from 0.15 mg/kg/h to 0.3 mg/kg/h
Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, PMI was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)
Pocc
Time Frame: Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, Pocc was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)

Changing trends in Pocc during remimazolam infusion from 0.15 mg/kg/h to 0.3 mg/kg/h
Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, Pocc was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h)
Richmond Agitation and Sedation Scale (RASS) score
Time Frame: Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, RASS score was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h).

Changing trends in RASS score during remimazolam infusion from 0.15 mg/kg/h to 0.3 mg/kg/h. The RASS scale ranges from -5 to +4. The lower the score, the deeper the level of sedation.
Remimazolam was initiated at 0.15 mg/kg/h and increased it by 0.025 mg/kg/h every 30 minutes, up to a maximum of 0.3 mg/kg/h, RASS score was measured after each infusion rate adjustment (0.15，0.175，0.20，0.225，0.25, 0.275, 0.3mg/kg/h).

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Capital Medical University

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Jian-Xin Zhou, Capital Medical University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
May 10, 2023

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 31, 2024

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
March 31, 2025

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
November 6, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 11, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
November 12, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 12, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 11, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • KY2023-182-04

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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings