NCT07211828

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

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

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 20 (estimated)
• Sponsor: Chi Kwan Fung · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

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

Detailed description

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.

Conditions

• Sedation and Analgesia
• Cholangiopancreatography, Endoscopic Retrograde
• Anesthesia, General

Interventions

Type	Name	Description
DRUG	high dose of alfentanil	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.
DRUG	low dose of alfentanil with propofol	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.

Timeline

• Start date: 2025-10-10
• Primary completion: 2026-12-31
• Completion: 2028-06-16
• First posted: 2025-10-08
• Last updated: 2026-03-27

Locations

1 site across 1 country: Taiwan