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)

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

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.

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