Minimum Alveolar Concentration of Sevoflurane With Nitrous Oxide Inducing Isoelectric EEG

February 3, 2014 updated by: Wei Mei, Huazhong University of Science and Technology

Minimum Alveolar Concentration of Sevoflurane With 60% Nitrous Oxide Inducing Isoelectric EEG in Mid-aged Adults

In order to investigate the effect of a combination effect of sevoflurane and nitrous oxide on cerebral electrical activity, the investigators determined the MAC of sevoflurane combined with nitrous oxide inducing isoelectric electroencephalogram (EEG) in 50% of the subjects (MACie) in middle aged subjects.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Anaesthesia was induced by sevoflurane in oxygen. Cisatracurium 0.15 mg kg-1 was administered after loss of the lash reflex, then ventilated manually until the amplitude of T1 decreased to 0. Intubation was performed and switched to mechanical ventilation with a fresh gas flow of 2 L min-1. Anesthesia was maintained by sevoflurane or sevoflurane+60% nitrous oxide respectively. The surgical incision was performed at least 30 min after tracheal intubation, provided that the predetermined end-tidal sevoflurane concentration had been constant for at least 30 min and that the difference between inspired and end-tidal concentrations was less than 10%.

Brain electrical activity was measured using Narcotrend Monitor and S/5 Compact Anaesthesia Monitor, which displayed unprocessed EEG and burst suppression ratio, respectively. The design of the experiment is referred to the "Dixon up-and-down" method. To avid anaesthesia awareness, the first subject was designed to receive end-tidal sevoflurane concentration of 2.5 %. The presence or absence of isoelectric EEG (Entropy Module) of the preceding patient determined the end-tidal concentration of sevoflurane given to the next patient (with an increment size of 0.2%). The isoelectric EEG was considered as significant when the isoelectric state last for more than 1 min. The maximal burst suppression rate was recorded if isoelectric EEG was not reached.

Study Type

Interventional

Enrollment (Actual)

76

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • China
    • Hubei
      • Wuhan, Hubei, China, 430030
        • Department of Anaesthesiology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

45 years to 64 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • between 45 to 64 years old
  • ASA physical status class 1 or 2
  • elective abdominal surgery
  • Informed Consent

Exclusion Criteria:

  • history of neurological disease
  • received central nervous system-active drugs
  • cardiac ejection fraction less than 40%
  • history of difficult intubation or anticipated difficult intubation
  • daily alcohol consumption
  • obesity, defined as a body-mass index of more than 30
  • without informed consent
  • others judged inappropriate as subjects for the study by the Study Chair

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Group 1 Sevoflurane+Nitrous oxide
Drug: Sevoflurane+Nitrous oxide
60% nitrous oxide +40% oxygen+ Sevoflurane
Active Comparator: Group 2 Sevoflurane
Drug: Sevoflurane
100% oxygen+ Sevoflurane

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
MACie
Time Frame: 30min
Minimal Alveolar Concentration of sevoflurane and NO inducing isoelectric electroencephalogram (EEG) in 50% of the subjects (MACie)
30min

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Huazhong University of Science and Technology

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

September 1, 2012

Primary Completion (Actual)

September 1, 2013

Study Completion (Actual)

October 1, 2013

Study Registration Dates

First Submitted

October 10, 2012

First Submitted That Met QC Criteria

October 11, 2012

First Posted (Estimate)

October 12, 2012

Study Record Updates

Last Update Posted (Estimate)

February 4, 2014

Last Update Submitted That Met QC Criteria

February 3, 2014

Last Verified

February 1, 2014

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • TJMZK20120903

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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