How remifentanil changes propofol-induced burst suppression.

Influence of Variable Plasma Concentrations of Remifentanil on Burst Suppression (BS) Event Rate in Electroencephalographic (EEG) Recordings of Human Subjects Undergoing Total Intravenous General Anesthesia (TIVA) Under Propofol

Not applicable Interventional University of Chile · NCT06237101

We will test whether different doses of remifentanil change the propofol concentration needed to produce burst suppression in adults (18–60) having elective surgery.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment20 (estimated)
Ages18 Years to 60 Years
SexAll
SponsorUniversity of Chile Academic / other
Locations2 sites (Santiago, RM and 1 other locations)
Trial IDNCT06237101 on ClinicalTrials.gov

What this trial studies

Adult patients (ASA I–II) undergoing low- or intermediate-risk elective surgery receive sequential remifentanil and propofol while frontal EEG is recorded. After loss of consciousness, patients are randomized to a medium or high remifentanil effect-site concentration and propofol infusion rates are adjusted to determine the concentration that produces burst suppression. Burst suppression thresholds (propofol concentrations) are compared between the remifentanil dose groups. Routine monitoring and neuromuscular blockade are used to facilitate standardized airway management and surgical conditions.

Who should consider this trial

Good fit: Adults aged 18–60 with ASA physical status I or II scheduled for low- or intermediate-risk elective surgery who are free of neurologic/psychiatric disease and not taking psychoactive drugs or opioids.

Not a fit: Patients with neurologic or psychiatric disorders, altered baseline consciousness, significant organ dysfunction, BMI over 35, current opioid or psychoactive drug use, or propofol allergy are excluded and would not benefit from participation.

Why it matters

Potential benefit: If successful, this could help anesthesiologists tailor anesthetic dosing to reduce unnecessary propofol exposure while maintaining appropriate EEG suppression.

How similar studies have performed: Prior work has shown that opioids can modify EEG patterns and interact with propofol, but direct randomized data specifically testing remifentanil's facilitation of propofol-induced burst suppression are limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* American Society of Anesthesiology I or II
* Elective surgery of low or intermediate risk

Exclusion Criteria:

* Neurological disease
* Psychiatric disease
* Use of psychoactive drugs or opioids
* Altered basal state of consciousness
* Allergy to propofol
* Body mass index \> 35 kg/m2
* Pre-existing renal, cardiac and/or hepatic dysfunction
* Patient's refusal to participate

Where this trial is running

Santiago, RM and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Anesthesia, IntravenousElectroencephalographyBurst Suppression
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.