Clinical trial NCT01720615: Detection of Consciousness by EEG and Auditory Evoked Potentials
Official title: Detection of Consciousness by EEG and Auditory Evoked Potentials
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Anesthesia
Electroencephalography/ Drug Effect
Keywords: EEG
AEP
Propofol
Sevoflurane
Remifentanil
General anesthesia
Lead sponsor: Technical University of Munich
Sponsor class: OTHER
First posted: 2012-11-02
Enrollment: 80
Sex: ALL
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: DIAGNOSTIC

Brief summary: The objective of the present investigation is to analyze EEG and auditory evoked potentials at the transition from consciousness to unconsciousness and vice versa. A set of electroencephalographic and auditory evoked potential parameters should be identified that allows separation of consciousness from unconsciousness (reflected by responsiveness/unresponsiveness to command). The study is based on data of 80 patients undergoing general anesthesia with remifentanil and either sevoflurane or propofol.

Detailed description: During the past years, monitoring of anesthetic effects on the main target of anesthesia, the brain, has gained increasing attention. Monitoring of the spontaneous electroencephalogram (EEG) and of auditory evoked potentials (AEP) has been suggested. Even if EEG and AEP reflect effects of anesthetic drugs, a visual interpretation is not expedient. As a consequence, several processing methods have been suggested that reduce the electroencephalogram to a numerical value. In the current study, a set of EEG- and AEP parameters based on different analysis methods is tested with respect to the parameters ability in separating consciousness (reflected by responsiveness to command) from unconsciousness at the transition between these stages. Therefore data of 80 unpremedicated patients undergoing general anesthesia with remifentanil and either sevoflurane or propofol is used. The study period is from induction of anesthesia until patients follow command after surgery and includes a reduction of the hypnotic agent after tracheal intubation until patients follow command. The isolated forearm technique is applied before muscle relaxants are given to maintain the ability to squeeze hand to command.

Eligibility criteria: Inclusion Criteria:

* American Society of Anesthesiologists (ASA) physical status 1-2
* Adult patients

Exclusion Criteria:

* Patients with contraindications to the study drugs
* psychiatric or neurologic disease
* drug abuse or medication known to affect the central nervous system
* pregnancy
* indication for rapid sequence induction

Primary outcomes:
measure: Changes in EEG- and AEP-parameters during loss- and return of consciousness
timeFrame: 1 day
Secondary outcomes:
measure: Impact of muscle activity on EEG- and AEP-parameters
timeFrame: 1 day
measure: Influence of anesthetics on EEG- and AEP-parameters
timeFrame: 1 day
Other outcomes:
Locations:
city: Munich
country: Germany
facility: Technische Universität München, Klinikum rechts der Isar, Department of Anesthesiology
state: Bavaria
Study officials:
affiliation: Klinikum rechts der Isar Technische Universität München
name: Eberhard F Kochs, MD
role: STUDY_CHAIR
References: