Detection of Consciousness by EEG and Auditory Evoked Potentials

Anesthesia Clinical Trial

Official title:

Detection of Consciousness by EEG and Auditory Evoked Potentials

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01720615
• Other study ID #: 2001
• Status: Completed
• Phase: Phase 4
• First received: October 29, 2012
• Last updated: October 31, 2012
• Start date: January 2001
• Est. completion date: April 2003

Study information

• Verified date: October 2012
• Source: Technische Universität München
• Contact: n/a
• Is FDA regulated: No
• Health authority: Germany: Ethics Commission
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 80
• Est. completion date: April 2003
• Est. primary completion date: November 2001
• Accepts healthy volunteers: No
• Gender: Both
• Age group: N/A and older

Eligibility

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

Study Design

Endpoint Classification: Pharmacokinetics/Dynamics Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic

Related Conditions & MeSH terms

• Anesthesia
• Electroencephalography/ Drug Effect

Intervention

Drug:
• Propofol / Remifentanil
General anesthesia: Loss of consciousness and standard clinical practice
• Sevoflurane / Remifentanil
General anesthesia: Loss of consciousness and standard clinical practice

Locations

Country	Name	City	State
Germany	Technische Universität München, Klinikum rechts der Isar, Department of Anesthesiology	Munich	Bavaria

Sponsors (1)

Lead Sponsor	Collaborator
Technische Universität München

Country where clinical trial is conducted

Germany, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Changes in EEG- and AEP-parameters during loss- and return of consciousness		1 day	Yes
Secondary	Impact of muscle activity on EEG- and AEP-parameters		1 day	Yes
Secondary	Influence of anesthetics on EEG- and AEP-parameters		1 day	Yes