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NCT Number: NCT07211828

EEG and Pain Monitor Data Under Anesthesia to Study Pharmacodynamic Effects of Opioids and Sedatives

Recording and analyzing electroencephalogram (EEG) and continuous pain monitor data under anesthesia in order to investigating the pharmacodynamic effects of opioids and sedatives.

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Key information

Conditions

Sedation and Analgesia Agnosia Anesthesia, General Cholangiopancreatography, Endoscopic Retrograde Nervous System Diseases Neurobehavioral Manifestations Neurologic Manifestations Pathological Conditions, Signs and Symptoms Perceptual Disorders Signs and Symptoms

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

About this study

The Patient State Index (PSI) is the main instrument used for monitoring brain waves during anesthesia. By using conductive patches to detect frontal lobe brainwave patterns, PSI helps assess the patient's depth of anesthesia. The Analgesia Nociception Index (ANI) is a heart rate variability (HRV)-based indicator that evaluates the activity of the autonomic nervous system (sympathetic and parasympathetic), thereby reflecting the patient's pain or stress response. PSI and ANI are often used together in anesthetized patients to avoid drug overdose.

Since opioids and sedative drugs interact with each other, different doses of opioids and sedatives have varying effects on brain waves, PSI, and ANI. This interaction has recently become a focus in anesthesiology and critical care medicine.

The purpose of this study is to use target-controlled infusion (TCI) to continuously administer opioids and sedative drugs, and to observe changes in the Patient State Index (PSI), raw EEG, and ANI data during the anesthesia process, in order to identify the effects of opioids and sedatives on PSI, EEG, and ANI.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Patients who under go ERCP who require general anesthesia

Exclusion criteria

  • ASA> or = 4 , vulnerable groups such as prisoners, patients with physical or mental disabilities and HIV carriers

Treatment and study plan

high dose of alfentanil

Drug

The initial dose is alfentanil cet 10ng/mL and propofol 1ug/mL. Dose of alfentanil will be increased by 10ng/mL each until PSI reach to 25-50. If alfentail has been adjusted to 50 but PSI is still too high, increase propofol cet by 0.5-1ug/mL till target PSI is reached. If propofol is adjusted to 0 but PSI is still too low, decrease alfetanil by 10ng/mL The range of dosage of alfentanil is 0-50ng/mL while propofol is 0-5ug/mL.

Other names: Alfenta, Alfentanil hydrochloride, Propofol (Diprivan)

low dose of alfentanil with propofol

Drug

Adjust dose of propofol to the upper limit before adjusting dose of alfentanil. Increase dose of propofol 0.5-1 ug/mL in order to have PSI valued 25-50. The initial dose of propofol is 1ug/mL, alfentanil 10 ng/mL. If propofol was adjusted to cet=5 ug/mL but PSI is still too high, increase alfentanil by 10 ng/mL instead. If alfentanil was adjusted to 0 but PSI is still too low, decrease propofol by 0.5-1 ug/mL instead . The range of dosage of propofol is 0-5 ug/mL while alfentanil is 0-50ng/mL.

Other names: Propofol (Diprivan), Alfenta, Alfentanil hydrochloride

Primary outcomes

  1. EEG alpha power to beta power ratio

    Time frame: Baseline and periprocedural

  2. EEG alpha ratio

    Time frame: baseline and periprocedural

  3. EEG delta ratio

    Time frame: baseline and periprocedural

  4. EEG beta ratio

    Time frame: baseline and periprocedural

  5. Patient State Index (PSI)

    Time frame: baseline and periprocedural

    A processed electroencephalogram (EEG) parameter derived from frontal EEG signals. It is being measured continuously by a EEG monitor.

Secondary outcomes

  1. Analgesia Nociception Index (ANI)

    Time frame: Baseline and periprocedural

    The Analgesia Nociception Index is measured by a continuous analgesia monitoring system . It is a numeric index (range from 0-100) indicating patients' nociception.

  2. Blood pressure

    Time frame: baseline and periprocedural

  3. Non-invasive cardiac output

    Time frame: during the whole sedation

    Cardiac output measured continuously by non-invasive monitoring (e.g., electrical cardiometry or equivalent device). The unit of measure is liters per minute (L/min)

  4. Heart rate

    Time frame: baseline and periprocedural

  5. Peripheral Capillary Oxygen Saturation (SpO₂)

    Time frame: baseline and periprocedural

    Continuous non-invasive measured by pulse oximetry,

  6. Non-invasive cardiac index

    Time frame: baseline and periprocedural

    Cardiac index calculated as cardiac output normalized to body surface area, measured non-invasively. The unit of measure is liters per minute per square meter (L/min/m²)

  7. Non-invasive Stroke Volume (SV)

    Time frame: baseline and periprocedural

    Stroke volume measured non-invasively, defined as the volume of blood ejected from the left ventricle per heartbeat.

Other outcomes

  1. Frequency of Patient Movement Events

    Time frame: Periprocedural

    The total number of movement events (defined as gross body motion, limb withdrawal, or head movement) recorded during the procedure

Study contacts

Contact information is provided by the study sponsor or research team.

Chi Kwan Boris Fung, MD

CONTACT

[email protected]

886-037-676811

Sponsors and collaborators

Lead sponsor

Chi Kwan Fung

Other

Collaborators

  • National Yang Ming Chiao Tung University
  • WeiGong Memorial Hospital

Registry information

Official study title

Pharmacodynamic Effects of Propofol and Alfentanil on EEG During Endoscopic Retrograde Cholangiopancreatography (ERCP)

Acronym: SED-ERCP

Important dates

Study start
2025
Primary completion
2026
Study completion
2028
First posted
Oct 8, 2025
Registry last updated
Mar 27, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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