Comparison of Modulations of Motor Brain Activity and SedLine After Median Nerve Stimulation in General Anesthesia

NCT07267403 | Recruiting

• 1 other identifier: STIM-PSI
• Study Type: interventional
• Target: 48
• Locations: 1 country
• Sites: 1

Brief Summary

To this date, no monitoring device can reliably detect episodes of accidental awakening during general anesthesia. One promising approach is the use of electroencephalography (EEG) to detect movement attempts via a brain-computer interface (BCI). Previous work has shown that combining a BCI with painless median nerve stimulation can detect cerebral motor activity under light propofol sedation. However, clinical data are still lacking regarding the persistence or otherwise of a cerebral motor response (neural synchronization, or ERS) induced by this stimulation during general anesthesia. In this new study, the aim is to simultaneously record the EEG centered on the motor cortex and the signal from the SedLine Patient State Index (PSI) to better characterize the evolution of cerebral motor activity before, during general anesthesia, and up to awakening. This approach will allow us to explore the complementarity of the two signals for future automated detection of residual states of consciousness during surgery. Preliminary data from a previous protocol (STIM-MOTANA) allowed to develop an EEG classification algorithm based on Riemannian geometry, capable of inferring a patient's state of consciousness from cortical responses induced by median nerve stimulation. The objective of this new study is also to compare the sensitivity of this algorithm with that of PSI, in order to assess its potential as a complementary - or even alternative - indicator of the level of consciousness under general anesthesia. Investigators hypothesize that it is possible to detect, using EEG, specific brain signatures related to median nerve stimulation, including during propofol-induced general anesthesia. Specifically, neuronal desynchronization and resynchronization phases (ERD/ERS), well characterized in wakefulness or light sedation, could partially persist at higher propofol concentrations. Parallel PSI recording will allow analyzing to what extent these EEG modulations are related to classically measured levels of consciousness, and to validate the relevance of the new algorithm based on Riemannian geometry as a tool for detecting intra-operative arousals.

Conditions

Accidental Awareness During General Anesthesia

Outcome Measures

Primary Outcomes (1)

• Motor activity modulations (ERD/ERS) patterns

  Detection of motor activity modulations (ERD/ERS) induced by median nerve stimulation by means of a EEG algorithm

  During the entire anesthesia

Study Arms (1)

Sedation by intravenous anesthesia with propofol concentration target.

EXPERIMENTAL

Any patient undergoing surgery requiring the use of sedation by intravenous anesthesia with propofol concentration target.

Device: EEG Headset; Device: SD LTM STIM (Micromed); Device: SedLine®

Interventions

EEG Headset DEVICE

64-electrode device (including 16 on the motor cortex), placed on the scalp. The EEG measurement is performed using OpenViBE software, in conjunction with an Eego amplifier (64 electrodes, ANT Neuro), both CE certified.

Sedation by intravenous anesthesia with propofol concentration target.

SD LTM STIM (Micromed) DEVICE

Median nerve stimulation: applied to the right forearm using two ECG electrodes positioned at the wrist (palmar side), allowing painless transcutaneous stimulation (intensity 3 to 14 mA; pulse duration: 0.1 ms; frequency: 5 Hz). The stimulator used is a SD LTM STIM model (Micromed), CE certified.

Sedation by intravenous anesthesia with propofol concentration target.

SedLine® DEVICE

Anesthetic depth monitoring: Performed using the SedLine® Brain Function Monitoring device (Masimo Corporation, model RDS7A, CE certified), using four forehead electrodes to record EEG activity. The Patient State Index (PSi), calculated in real time, is interpreted within a target range of 25 to 50 to ensure adequate general anesthesia. The device complies with international standards for electrical safety (IEC 60601) and hospital use.

Sedation by intravenous anesthesia with propofol concentration target.

Eligibility Criteria

• Age: 18 Years - 81 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Right-handed patient
• Scheduled for surgery using intravenous anesthesia with propofol concentration

You may not qualify if:

• Allergy to propofol, soy, or peanuts.
• BMI \< 20 or \> 30
• Pregnant or breastfeeding women
• Medical or surgical history that may interfere with median nerve stimulation or EEG signal acquisition (e.g., diabetes, polyneuropathy, central neurodegenerative disease, epilepsy, brain surgery)
• History of right median nerve injury
• Right upper limb amputation
• Upper limb surgery
• Unable to wear an EEG headset (prone position, head and neck surgery)
• Drug abuse

Sponsors & Collaborators

• Brugmann University Hospital: lead

Study Sites (1)

CHU Brugmann

Brussels, 1020, Belgium

RECRUITING

Study Officials

• Seyed Javad Bidgoli, MD

  CHU Brugmann

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Seyed Javad Bidgoli, MD

CONTACT

02 477 21 79; seyedjavad.bidgoli@chu-brugmann.be@chu-brugmann.be

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Head of clinical research unit

Study Record Dates

• First Submitted: November 25, 2025
• First Posted: December 5, 2025
• Study Start: October 27, 2025
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026
• Last Updated: December 5, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will not share

Locations

BE (1)