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EEG-based Depth of Anesthesia-monitoring, Effects on Dosage and Cognition

Primary Purpose

Postoperative Complications, Delayed Emergence From Anesthesia, Cognitive Dysfunction

Status
Recruiting
Phase
Not Applicable
Locations
Norway
Study Type
Interventional
Intervention
Bilateral Bispectral Index and EEG
Sponsored by
Oslo University Hospital
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional other trial for Postoperative Complications focused on measuring Depth of Anesthesia Monitoring, Post operative cognitive dysfunction (POCD)

Eligibility Criteria

18 Years - 85 Years (Adult, Older Adult)All SexesDoes not accept healthy volunteers

Inclusion Criteria

.

Participants are eligible to be included in the study only if all of the following criteria apply:

Age

  1. Participant must be above the age of 18 years , at the time of signing the informed consent.

    Sex

  2. Male and/or female

    Informed Consent

  3. Capable of giving signed informed consent as described in protocol which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in the protocol

    Exclusion Criteria

    Participants are excluded from the study if any of the following criteria apply:

  4. Psychiatric disorders
  5. Pregnancy
  6. Breast feeding
  7. Using antiepileptic drugs.
  8. Central neurological disease
  9. Unable to complete baseline CANTAB-test.

Sites / Locations

  • Oslo University HospitalRecruiting

Arms of the Study

Arm 1

Arm 2

Arm Type

Experimental

Experimental

Arm Label

Visual EEG

Blinded EEG

Arm Description

Individual dosing of anesthetic medications based on EEG AND other standardized clinical observations (BP, HR)

Individual dosing of anesthetic medications based on standardized clinical observations (BP, HR).

Outcomes

Primary Outcome Measures

EEG-based Depth of anesthesia-monitoring and dosage of anesthetic medications
Summarizing the total amount of anesthetic drugs used, mg/kg/hr
EEG-based Depth of anesthesia-monitoring and dosage of vasopressor medications during anesthesia
Summarizing the total amount of vasopressor drugs used, micg/kg/min
EEG-based Depth of anesthesia-monitoring and time to wake-up after surgery
Time from the end of intravenous infusion of anesthetic - to motoric and verbal response.
Evaluation of cognitive function using CANTAB-MCI
Baseline assessment 1 day preoperatively, assessment 2-3 hours after wake-up, and 24 hours after wake-up using CANTAB-MCI

Secondary Outcome Measures

Full Information

First Posted
March 13, 2020
Last Updated
April 19, 2022
Sponsor
Oslo University Hospital
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1. Study Identification

Unique Protocol Identification Number
NCT04529304
Brief Title
EEG-based Depth of Anesthesia-monitoring, Effects on Dosage and Cognition
Official Title
EEG-based Depth of Anesthesia-monitoring During General Anesthesia - Effects on Time to Wake-up and Post-operative Cognition
Study Type
Interventional

2. Study Status

Record Verification Date
April 2022
Overall Recruitment Status
Recruiting
Study Start Date
January 8, 2021 (Actual)
Primary Completion Date
March 15, 2023 (Anticipated)
Study Completion Date
December 20, 2023 (Anticipated)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Principal Investigator
Name of the Sponsor
Oslo University Hospital

4. Oversight

Studies a U.S. FDA-regulated Drug Product
No
Studies a U.S. FDA-regulated Device Product
No
Data Monitoring Committee
Yes

5. Study Description

Brief Summary
Depth of anesthesia-monitoring based on EEG changes demands knowledge about the effects of the different anesthetic medications on EEG waveforms. The investigators want to investigate the use of the raw-EEG waveform in addition to indexes (BIS) and EEG spectrogram analyses for depth of anesthesia monitoring. The investigators hypothesize that with the use of this monitoring, anaesthesia providers will be able to better individualize the dosage of anesthetic drugs, and that this will reduce the total consumption of anesthetic medication , thus reducing time to wake-up after surgery. Some studies have indicated that too deep anesthesia, confirmed by "burst-suppression" or isoelectric-EEG , is associated with increased postoperative cognitive dysfunction (POCD). The investigators will therefore assess the patients with the Cambridge Neuropsychological Test Automated Battery tests in mild cognitive impairment (CANTAB-MCI) cognitive function assessment tool.
Detailed Description
It has been over 80 years since Gibbs et al showed how the electroencephalogram (EEG) systematically changed in concurrence with increasing doses of hypnotic drugs such as penthobarbital and Ether. The study concluded that "Electroencephalography may therefore be of value in controlling depth of anesthesia and sedation". In spite of a solid documentation of the systematic connection between dosing of anesthetic drugs, EEG-patterns and level of sedation/anesthesia , EEG-based DoA has not become a part of standard of care in anesthetic management. There is abundant evidence of how different anesthetic drugs leads to characteristic fluctuations in human brain electrical activity, relating to depth of anesthesia, anesthetic drug of choice, and age . These anesthetic induced fluctuations are readily visible as changes in the patients EEG. Anesthetic drugs are usually administered in pharmacological models based on a population taking into account their age, weight and height. However, there is a significant difference in how patients respond to these models. In adults there is evidence that the doses needed to achieve consciousness varies with a factor of 2 above and below suggested doses. In under-dosing of anesthetics there is a risk of peroperative awareness . On the other hand there is also evidence that overdosing of anesthetics has harmful effects; children receiving more than 4% Sevoflurane can demonstrate epileptiform activity , and adults overdosing into "burst suppression" during anesthesia has a higher risk of postoperative delirium (POD) and increased occurrence of postoperative cognitive dysfunction (POCD) . Bispectral Index (BIS) is an algorithm developed by Aspect Medical Systems in 1994, which is based on weighted sums of EEG subparameters to present an index from 0 to 100 for depth of anesthesia, where 100 is wide awake, and 0 is an isoelectric EEG. The BIS target for a deep enough anesthesia is set to be between 40 and 60. The BIS number is often in concurrence with other clinical observations related to anesthetic depth, however there is also an experience of divergence. BIS and other EEG-based indices are programmed from adult cohorts, and cannot be directly trusted in children, or the elderly . There is also an incapability in these preprogrammed indices (BIS and other) to integrate how specific anesthetic drugs affect the EEG, and thenceforth the BIS value. An example of this is how the drug Ketamine induces a specific gamma-frequency in the EEG, which the BIS-index translate as a lighter anesthesia, even though the drug is administered "on top of" an already deep level of anesthesia.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Postoperative Complications, Delayed Emergence From Anesthesia, Cognitive Dysfunction
Keywords
Depth of Anesthesia Monitoring, Post operative cognitive dysfunction (POCD)

7. Study Design

Primary Purpose
Other
Study Phase
Not Applicable
Interventional Study Model
Parallel Assignment
Model Description
Two groups with 50 participants in each group. We want to compare one group with visible EEG-monitor with a group where the EEG monitor is invisible to the anesthetic team.
Masking
ParticipantCare ProviderOutcomes Assessor
Masking Description
Patient is blinded to intervention. Outcome assessoring done by patient/IPAD-solution from CANTAB, patient status assessed by blinded care-provider (nurse)
Allocation
Randomized
Enrollment
100 (Anticipated)

8. Arms, Groups, and Interventions

Arm Title
Visual EEG
Arm Type
Experimental
Arm Description
Individual dosing of anesthetic medications based on EEG AND other standardized clinical observations (BP, HR)
Arm Title
Blinded EEG
Arm Type
Experimental
Arm Description
Individual dosing of anesthetic medications based on standardized clinical observations (BP, HR).
Intervention Type
Device
Intervention Name(s)
Bilateral Bispectral Index and EEG
Intervention Description
raw-EEG and spectrographic EEG-visualization based on the Medtronic Device "Bilateral BiSpectral Index"
Primary Outcome Measure Information:
Title
EEG-based Depth of anesthesia-monitoring and dosage of anesthetic medications
Description
Summarizing the total amount of anesthetic drugs used, mg/kg/hr
Time Frame
24 hours
Title
EEG-based Depth of anesthesia-monitoring and dosage of vasopressor medications during anesthesia
Description
Summarizing the total amount of vasopressor drugs used, micg/kg/min
Time Frame
24 hours
Title
EEG-based Depth of anesthesia-monitoring and time to wake-up after surgery
Description
Time from the end of intravenous infusion of anesthetic - to motoric and verbal response.
Time Frame
24 hours
Title
Evaluation of cognitive function using CANTAB-MCI
Description
Baseline assessment 1 day preoperatively, assessment 2-3 hours after wake-up, and 24 hours after wake-up using CANTAB-MCI
Time Frame
1 day preoperatively to 24 hours after wake-up

10. Eligibility

Sex
All
Minimum Age & Unit of Time
18 Years
Maximum Age & Unit of Time
85 Years
Accepts Healthy Volunteers
No
Eligibility Criteria
Inclusion Criteria . Participants are eligible to be included in the study only if all of the following criteria apply: Age Participant must be above the age of 18 years , at the time of signing the informed consent. Sex Male and/or female Informed Consent Capable of giving signed informed consent as described in protocol which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in the protocol Exclusion Criteria Participants are excluded from the study if any of the following criteria apply: Psychiatric disorders Pregnancy Breast feeding Using antiepileptic drugs. Central neurological disease Unable to complete baseline CANTAB-test.
Central Contact Person:
First Name & Middle Initial & Last Name or Official Title & Degree
Anders Aasheim, Master
Phone
+4748129280
Email
uxanim@ous-hf.no
First Name & Middle Initial & Last Name or Official Title & Degree
Luis G Romundstad, MD, PhD
Email
luirom@ous-hf.no
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Luis G Romundstad, MD, PhD
Organizational Affiliation
Oslo University Hospital
Official's Role
Principal Investigator
Facility Information:
Facility Name
Oslo University Hospital
City
Oslo
ZIP/Postal Code
0124
Country
Norway
Individual Site Status
Recruiting

12. IPD Sharing Statement

Plan to Share IPD
Yes
IPD Sharing Plan Description
Data storage and management will follow GCP and GDPR requirements. Data sharing after end of study will follow the current data sharing policy at Oslo University Hospital. Data set can be made available for journal peer review process.
IPD Sharing Time Frame
After end of study, 2025, and 5 years.
IPD Sharing Access Criteria
Access through application to study contactpersons.
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EEG-based Depth of Anesthesia-monitoring, Effects on Dosage and Cognition

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