Improving Information Extraction From EEG on Cerebral Anesthetic Drug Effects

Not Applicable

Completed

Brief Summary: This is an interventional, randomized controlled study in health volunteers that involves collecting data on raw EEG waves measuring various combinations of anesthetic drugs during standardized drug titration.

Recruitment & Eligibility

Inclusion Criteria

Healthy volunteers aged 18 to 70 years
Concerning the cognitive function: Volunteers are considered to have sufficient cognitive reserve if they are able to read and comprehend the patient information form, if they can adequately answer the anamnestic questions during the screening process and if they are allowed to provide legitimate written informed consent
No selection will be made regarding ethnic background.
For this study no control group has been selected as EEG is compared between episodes rather than between individuals (each volunteer is his/her own control)

Exclusion Criteria

Volunteer refusal

Volunteer < 18 years and >70 years
Pregnancy
Exclusion criteria are weight less than 70% or more than 130% of ideal body weight
Neurological disorder (epilepsy, the presence of a brain tumor, a history of brain surgery, hydrocephalic disorders, depression needing treatment with anti-depressive drugs, a history of brain trauma, a subarachnoidal bleeding, TIA or cerebral infarct, psychosis or dementia , schizophrenia, alcohol or drug abuse).
Diseases involving the cardiovascular system (hypertension, coronary artery disease, prior acute myocardial infarction, any valvular and/or myocardial disease involving decrease in ejection fraction, arrhythmias, which are either symptomatic or require continuous medication/pacemaker/automatic internal cardioverter defibrillator
Pulmonary Diseases
Gastric Diseases
Endocrinologic diseases
Recent use of psycho-active medication (benzodiazepines, anti-epileptic drugs, parkinson medication, anti-depressant drugs, opioids) or more than 20g of alcohol daily

Arm && Interventions

Group	Intervention	Description
Healthy Volunteers	SedLine EEG sensor	All healthy volunteers will receive four sessions of anesthesia with different common drug combinations while having SedLine EEG sensors placed on their forehead during these sessions to study the effects of these drugs on the brain. The sessions were: propofol (P), sevoflurane (S), propofol with remifentanil (PR), and sevoflurane with remifentanil (SR).

Primary Outcome Measures

Name	Time	Method
Patient State Index (PSI) Comparison, Baseline and Emax	6 weeks	Patient State Index (PSI-1) is a processed EEG parameter that quantifies the level of EEG inhibition. A new algorithm (PSI-2) has been created to improve performance in low power EEG. PSI is unitless. It ranges between 100 and 0 (100 representing 'awake state', 0 denoting 'no detectable electrical brain activity'). PSI-1 and PSI-2 were compared in their correlation with measured propofol and sevoflurane concentrations with or without remifentanil (0, 2 ,or 4 ng/mL) via several estimated PD model parameters. In the data table, BL (Baseline) denotes PSI-2 measurements when no drug is present; Emax denotes PSI in the presence of the maximum drug effect; C50 is the drug concentration which produces 50% of the maximal drug effect (ug/mL for Propofol C50, vol% for Sevoflurane C50).

Secondary Outcome Measures