ClinicalTrials.gg
CompletedNCT07303985Updated Apr 15, 2026

The Effects of Remimazolam on Cerebral Blood Flow Following General Anesthesia Induction

A Phase 3 interventional study of Remimazolam and Propofol (Group P) in Cerebral Blood Flow, sponsored by Jun Zhang. Completed at 1 site in China. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-04-15.

Sponsored by Jun Zhang · Phase 3, Interventional, and Prevention

Phase
Phase 3
Study type
Interventional
Enrollment
52
Allocation
Randomized
Ages
18 Years and older
Sex
All
01

Study summary

This study will enroll 40 subjects aged 18 years or older scheduled for elective surgery under general anesthesia with endotracheal intubation. Basic medical history information will be collected. Subjects will be divided into two groups of 20 each: a remimazolam group and a propofol group. The study period will span from one day before surgery to one day after surgery. The study will assess middle cerebral artery cerebral blood flow following general anesthesia induction and postoperative anesthesia recovery.

Read the detailed description

A significant reduction in cerebral blood flow (CBF) frequently occurs following general anesthesia induction. This decrease in CBF can lead to a reduction in the delivery of oxygen and glucose to brain tissue. If the magnitude or duration of this reduction exceeds the compensatory capacity of cerebral autoregulation, it can result in an imbalance between cerebral oxygen supply and demand, thereby increasing the risk of cerebral ischemia and neurological injury. Patients who are elderly, have hypertension, a history of cerebrovascular disease (e.g., stroke, intracranial arterial stenosis), or pre-existing brain injury are at higher risk for pronounced CBF reduction after induction, making them more susceptible to postoperative cognitive dysfunction, exacerbation of existing deficits, or new ischemic events. This underscores the urgent need to identify effective and safe therapeutic strategies to mitigate this risk.

Remimazolam is a novel benzodiazepine agent, structurally derived from midazolam with the introduction of a metabolically labile methyl propionate side chain. It similarly acts on the GABAA receptor, promoting chloride ion influx and inhibiting neuronal electrical activity. Administered intravenously for sedation and hypnosis, it is characterized by rapid onset, short duration of action, rapid recovery, minimal accumulation, and metabolism independent of hepatic or renal pathways. Previous studies indicate that benzodiazepines generally lack significant cardiovascular depressant effects and are associated with a lower incidence of hemodynamic instability during anesthesia induction. However, the specific impact of remimazolam on CBF following general anesthesia induction remains unclear.

Therefore, to further elucidate the effects of this novel benzodiazepine, remimazolam-which reportedly lacks significant cardiovascular depression-on CBF post-induction, we propose the following strategies for our clinical study: (1) compare remimazolam with the commonly used agent propofol for anesthesia induction; (2) administer remimazolam as an intravenous bolus of 0.3 mg/kg and propofol at 2 mg/kg for induction; (3) implement goal-directed fluid management during the peri-induction period; (4) utilize ultrasound to monitor blood flow in the middle cerebral artery; and (5) assess postoperative recovery parameters. Through this comprehensive approach, we aim to determine whether remimazolam offers a protective or optimizing effect on CBF during general anesthesia induction, thereby providing an empirical foundation for its routine clinical use in this context.

02

Conditions studied

  • Cerebral Blood Flow

Keywords

  • Remimazolam
  • Propofol
  • Cerebral blood flow
03

In context

Lead sponsor

Jun Zhang is the lead sponsor of 21 studies on the registry; 2 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Patients who have signed the form and are willing to comply with the study protoco
  • Age greater than 18 years
  • classification I to II
  • Scheduled for elective surgery
  • Undergoing general anesthesia with endotracheal intubation
  • No history of cerebrovascular disease, carotid artery stenosis, or traumatic brain injury.

Exclusion criteria

Exclusion Criteria:

  • History of intracranial lesions, carotid artery stenosis, or traumatic brain injury
  • Allergy or to remimazolam or propofol.
Terms in these criteria, in plain language(3)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

ASA physical status

The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

05

Study design

Phase
Phase 3
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Triple (Participant, Care provider, Outcomes assessor)
Enrollment
52 participants (actual)

Study arms

  • Other
    Propofol

    Propofol is used as the sedative agent during the anesthesia induction period.

    Drug: Propofol (Group P)

  • Experimental
    Remimazolam

    Remimazolam is used as the sedative agent during the anesthesia induction period.

    Drug: Remimazolam

Interventions

  • Remimazolam is used as the sedative agent during the anesthesia induction period (administer remimazolam as an intravenous bolus of 0.3 mg/kg for induction).

    Also known as: Experimental

  • Propofol is used as the sedative agent during the anesthesia induction period (administer propofol at 2 mg/kg for induction).

    Also known as: Comparator

06

What researchers measure

Primary outcomes

  1. Peak systolic blood flow velocity (PS)

    Peak systolic blood flow velocity (PS) in the middle cerebral artery following general anesthesia induction (at 1, 3, 5, and 10 minutes after endotracheal intubation). Peak systolic blood flow velocity (PS) is the maximum speed of blood flow recorded during the systolic phase of the cardiac cycle, typically measured in centimeters per second (cm/s). Peak systolic blood flow velocity (PS) normal values are vessel-specific and age-dependent. In healthy adults, the commonly cited reference range for the middle cerebral artery (MCA) is approximately 80-120 cm/s. This value decreases with age. For other intracranial arteries, PS is generally lower (e.g., 40-80 cm/s for vertebrobasilar arteries). Physiological factors like hematocrit and gender also cause minor variations. Clinically, PS values above 140-200 cm/s in the MCA often indicate significant pathology such as vasospasm or stenosis.

    Time frame: 1, 3, 5, and 10 minutes after endotracheal intubation.

Secondary outcomes

  1. The resistance index (RI) of the middle cerebral artery

    The resistance index (RI) of the middle cerebral artery (MCA) is a hemodynamic parameter. It reflects downstream cerebrovascular resistance and is defined by the formula: RI = (Peak Systolic Velocity - End-Diastolic Velocity) / Peak Systolic Velocity. A normal RI in the MCA for healthy adults typically ranges from 0.50 to 0.70 (or 50-70%). Values are influenced by age, with neonates and infants having higher normal values (often up to 0.80-0.85) which decrease toward adult levels with maturation. In elderly individuals, a slight increase may be observed due to reduced vascular compliance. An elevated RI (\>0.80) generally indicates increased distal vascular resistance, which can be caused by intracranial hypertension, severe microangiopathy, or brain death. A very low RI (\<0.50) may suggest a hyperemic state or proximal stenosis.

    Time frame: 1, 3, 5, and 10 minutes after endotracheal intubation

  2. Mean blood flow velocity (MV)

    Mean blood flow velocity (MV), often referred to as Time-Averaged Maximum Velocity (TAMV), is a key hemodynamic parameter measured by Doppler ultrasound. It represents the average speed of the fastest-moving blood cells within a vessel over one complete cardiac cycle. For the middle cerebral artery (MCA) in healthy adults, the normal MV typically ranges from 40 to 65 cm/s. This value is age-dependent, being higher in children and gradually decreasing with advancing age. A sustained MV outside this range, particularly when asymmetric compared to the contralateral side, can indicate pathological conditions such as stenosis, hyperemia, or impaired autoregulation. Its calculation integrates both systolic and diastolic flow, making it a stable indicator of overall cerebral perfusion.

    Time frame: 1, 3, 5, and 10 minutes after endotracheal intubation

  3. Pulsatility index (PI)

    The Pulsatility Index (PI) is a dimensionless hemodynamic parameter derived from Transcranial Doppler (TCD) ultrasound. It quantifies the pulsatility of the blood flow waveform, reflecting downstream cerebrovascular resistance. It is calculated using the formula: PI = (Peak Systolic Velocity - End-Diastolic Velocity) / Mean Velocity. For the middle cerebral artery (MCA) in healthy adults, the normal PI typically ranges from 0.70 to 1.10. Age significantly influences this value; neonates have a much higher normal PI (often \>1.50), which decreases to adult levels during childhood. An elevated PI (\>1.20) generally indicates increased distal resistance, which can be caused by intracranial hypertension or small vessel disease. Conversely, a very low PI (\<0.60) may suggest a hyperdynamic state or proximal stenosis.

    Time frame: 1, 3, 5, and 10 minutes after endotracheal intubation

  4. Postoperative recovery time

    post-anesthesia care unit (PACU) length of stay. There is no single universal "normal value" for Post-Anesthesia Care Unit (PACU) length of stay, as it is highly dependent on the type of surgery, anesthesia technique, institutional protocols, and patient-specific factors. For straightforward, outpatient, or minor inpatient surgeries, a typical stay often ranges from 30 minutes to 2 hours. The primary discharge criteria are based on standardized scoring systems, most commonly the Aldrete score or its modifications. Patients must achieve a predetermined score (usually ≥9 out of 10) indicating stable vital signs, adequate oxygenation, intact consciousness, and controlled pain and nausea before discharge to a ward or home. Prolonged stays beyond expected benchmarks are used as a quality indicator to identify and address potential complications like postoperative nausea and vomiting, pain, or hemodynamic instability.

    Time frame: During the post-anesthesia care unit (PACU)

  5. Postoperative cognitive score

    Postoperative cognitive score was assessed by the Mini-Mental State Examination, MMSE). MMSE is a standardized, 30-point questionnaire used to screen for cognitive impairment. It assesses five key domains: orientation (to time and place), registration and recall of words, attention and calculation (e.g., serial sevens), language abilities (naming, repetition, comprehension, reading, writing), and visual construction (copying a pentagon). Administration involves a trained examiner asking the patient specific questions in a quiet setting, typically taking 5-10 minutes. One point is awarded for each correct task, with a maximum total score of 30. Results are interpreted based on the total score: 27-30 suggests normal cognition, 24-26 indicates mild cognitive impairment, 19-23 signifies moderate impairment, and a score ≤18 points to severe impairment.

    Time frame: On the first postoperative day.

07

Study locations

1 site
  • Fudan University Shanghai Cancer Centre
    Shanghai, China
08

References and documents

Individual participant data

Plan to share: No — The data sets are available from the corresponding author on reasonable request

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Apr 15, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT07303985
Lead sponsor
Jun Zhang
Responsible party
Jun Zhang (Professor, Fudan University) — Sponsor-investigator
First posted
Dec 26, 2025
Start date
Dec 29, 2025
Primary completion
Feb 28, 2026
Completion
Mar 1, 2026
Last update
Apr 15, 2026

Study contacts

Jun Zhang
principal investigator · Fudan University Shanghai Cancer Centre

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Studies of the drug tested here: Remimazolam

Start the discussion