BIS-EEGNCT07042906
Comparison of the Factors Affecting PSI and BIS Values in Monitoring Anesthetic Depth During Open-Heart Surgery
An observational study of BIS-EEG and PSI, run by Kocaeli University at 1 site in Turkey (Türkiye).
Trial summary
Measurement of anesthetic depth has long been a subject of investigation, aiming to titrate anesthetic agents appropriately and to prevent intraoperative awareness and consciousness. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- BIS-EEG, PSI, Open Heart Surgery
- What is being tested?
- anesthesia depth monitorizing, awareness
- Type of treatment
- Medical device
- How many people
- 46 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 18 Jan 2024to 18 Jul 2025
- How long will I take part?
- 2 Days
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- Adult, Older adult
Study population: "This study will be conducted with the approval of the Ethics Committee of Kocaeli University Faculty of Medicine Hospital and after obtaining written informed consent from all participants. The aim of our study is to investigate the factors influencing the BIS (Bispectral Index) and PSI (Patient State Index) methods, which are used to assess the depth of anesthesia in patients undergoing open-heart surgery with the use of a cardiopulmonary bypass (CPB) machine at Kocaeli University Faculty of Medicine Hospital."
Who may be able to join
- "Patients aged 18 to 65 years,
- Classified as ASA (American Society of Anesthesiologists) physical status II-III,
- scheduled for elective open-heart surgery via median sternotomy
Who cannot join
- "Patients with an ejection fraction below 35%,
- Those with pre-existing central nervous system disorders (e.g., history of epileptic seizures or intracranial space-occupying lesions),
- A history of prior open cranial surgery,
- Known allergies to anesthetic agents, alcohol or substance abuse,
- Any other conditions deemed to negatively affect the BIS profile (e.g., patients with preoperative intra-aortic balloon pump insertion, those undergoing surgery under inotropic support, or receiving preoperative sedative infusions),
- As well as patients scheduled to undergo antegrade or retrograde cerebral perfusion or total circulatory arrest
Trial locations and contacts
1 site in 1 country.
About this study
Measurement of anesthetic depth has long been a subject of investigation, aiming to titrate anesthetic agents appropriately and to prevent intraoperative awareness and consciousness. Many patients undergoing surgery experience fear and anxiety regarding the possibility of remaining conscious, perceiving pain, and being unable to move during anesthesia. Intraoperative awareness-defined as consciousness during anesthesia with explicit recall afterward-is a distressing condition that can lead to post-traumatic stress disorder.
However, aiming for excessively deep anesthesia to avoid the possibility of awareness during surgery is not recommended, as it may result in hemodynamic instability due to the effects of anesthetic agents and may impair postoperative cognitive functions, particularly in the elderly population.
Read more
Common methods used in monitoring anesthetic depth include observing sweating, lacrimation, pupillary dilation, heart rate variability, and blood pressure. However, some of these are subjective and may not always be reliable indicators.
Electroencephalogram (EEG)-based monitors such as the Bispectral Index (BIS) and the Patient State Index (PSI) offer more reliable and objective means of monitoring anesthetic depth. These monitors provide numerical values between 0 (indicating unconsciousness) and 100 (indicating full alertness) based on proprietary algorithms, offering valuable insight into the patient's anesthetic state.
"Our aim is to examine BIS and PSI values and to investigate the factors that influence these parameters."
- Conditions
- BIS-EEG, PSI, Open Heart Surgery, Anesthesia Depth Monitoring
- Being tested
- anesthesia depth monitorizing, awareness
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
anesthesia depth monitorizing, awarenessDevice
Investigation of BIS and PSI Monitoring Methods for Anesthetic Depth and the Factors Affecting These Methods in Open-Heart Surgery
What is being measured
The primary outcome is the main question the study is designed to answer.
The primary objective of this study is to measure the correlation between BIS and PSI values, which are parameters used to monitor the depth of anesthesia during open-heart surgery.
BIS (Bispectral Index) is a monitoring method that uses EEG (electroencephalogram) data to measure the depth of anesthesia. It has been used for a long time to assess anesthetic depth. PSI (Patient State Index) is a monitoring method that has become more popular in recent years for measuring the depth of anesthesia. The recommended reference ranges for anesthetic depth are 40-60 for BIS and 25-50 for PSI. The primary objective of this study is to measure the correlation between PSI and BIS values during open-heart surgery.
Measured: Data will be collected over a 12-month period and subjected to statistical analysis.
Secondary outcomes (1)
The secondary objective of this study is to measure the effect of hypothermia, which develops after patients are connected to the cardiopulmonary bypass (CPB) machine during open-heart surgery, on BIS and PSI values that indicate the depth of anesthesia
BIS is a monitoring method that uses EEG (electroencephalogram) data to measure the depth of anesthesia. It has been used for a long time for this purpose. PSI is a monitoring method that has become more popular in recent years for assessing anesthetic depth. The recommended reference ranges for anesthetic depth are 40-60 for BIS and 25-50 for PSI. In the literature, there are studies suggesting that the decrease in body temperature (hypothermia) during cardiopulmonary bypass (CPB) in open-heart surgery is similar to the decrease observed in BIS and PSI values. In this study, our secondary objective is to measure the similarity between the decrease in body temperature and the decrease in BIS and PSI values.
Measured: Data will be collected over a 12-month period and subjected to statistical analysis.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 Jun 2025
- Study start18 Jan 2024
- Primary completion18 Jan 2025
- Study completion18 Jul 2025 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for BIS-EEGStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Other
- Time perspective
- Prospective
- Enrolment
- 46 participants (actual)
- Target duration
- 2 Days
Sponsor and investigators
- Lead sponsor
- Kocaeli University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Mahsum Mazlum Mentes, Kocaeli University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07042906
- Sponsor's protocol ID
- GOKAEK-2023/06.13
- Status last verified
- May 2025
- First submitted
- 14 May 2025
- Last updated
- 29 Jun 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 29 Jun 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of the Factors Affecting PSI and BIS Values in Monitoring Anesthetic Depth During Open-Heart Surgery
- ClinicalTrials.gov ID
- NCT07042906
- Acronym / sponsor ID
- GOKAEK-2023/06.13
- Conditions
- BIS-EEG, PSI, Open Heart Surgery, Anesthesia Depth Monitoring
- Study type
- Observational
- Recruitment status
- Active, not recruiting
- Enrolment
- 46 participants (actual)
- Lead sponsor
- Kocaeli UniversityUniversity, hospital or other
- Study start
- 18 Jan 2024 (actual)
- Primary completion
- 18 Jan 2025 (actual)
- Study completion
- 18 Jul 2025 (estimated)
- First posted
- 29 Jun 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Measurement of anesthetic depth has long been a subject of investigation, aiming to titrate anesthetic agents appropriately and to prevent intraoperative awareness and consciousness. Many patients undergoing surgery experience fear and anxiety regarding the possibility of remaining conscious, perceiving pain, and being unable to move during anesthesia. Intraoperative awareness-defined as consciousness during anesthesia with explicit recall afterward-is a distressing condition that can lead to post-traumatic stress disorder.
However, aiming for excessively deep anesthesia to avoid the possibility of awareness during surgery is not recommended, as it may result in hemodynamic instability due to the effects of anesthetic agents and may impair postoperative cognitive functions, particularly in the elderly population.
Common methods used in monitoring anesthetic depth include observing sweating, lacrimation, pupillary dilation, heart rate variability, and blood pressure. However, some of these are subjective and may not always be reliable indicators.
Electroencephalogram (EEG)-based monitors such as the Bispectral Index (BIS) and the Patient State Index (PSI) offer more reliable and objective means of monitoring anesthetic depth. These monitors provide numerical values between 0 (indicating unconsciousness) and 100 (indicating full alertness) based on proprietary algorithms, offering valuable insight into the patient's anesthetic state.
"Our aim is to examine BIS and PSI values and to investigate the factors that influence these parameters."
Study design
- Observational model
- Other
- Time perspective
- Prospective
- Target follow-up
- 2 Days
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Age groups
- Adult, Older adult
- Study population
- "This study will be conducted with the approval of the Ethics Committee of Kocaeli University Faculty of Medicine Hospital and after obtaining written informed consent from all participants. The aim of our study is to investigate the factors influencing the BIS (Bispectral Index) and PSI (Patient State Index) methods, which are used to assess the depth of anesthesia in patients undergoing open-heart surgery with the use of a cardiopulmonary bypass (CPB) machine at Kocaeli University Faculty of Medicine Hospital."
Key inclusion criteria (3 listed)
- "Patients aged 18 to 65 years,
- Classified as ASA (American Society of Anesthesiologists) physical status II-III,
- scheduled for elective open-heart surgery via median sternotomy
Key exclusion criteria (6 listed)
- "Patients with an ejection fraction below 35%,
- Those with pre-existing central nervous system disorders (e.g., history of epileptic seizures or intracranial space-occupying lesions),
- A history of prior open cranial surgery,
- Known allergies to anesthetic agents, alcohol or substance abuse,
- Any other conditions deemed to negatively affect the BIS profile (e.g., patients with preoperative intra-aortic balloon pump insertion, those undergoing surgery under inotropic support, or receiving preoperative sedative infusions),
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| anesthesia depth monitorizing, awarenessInvestigation of BIS and PSI Monitoring Methods for Anesthetic Depth and the Factors Affecting These Methods in Open-Heart Surgery | Device | – |
Primary outcome
The primary objective of this study is to measure the correlation between BIS and PSI values, which are parameters used to monitor the depth of anesthesia during open-heart surgery.
Time frame: Data will be collected over a 12-month period and subjected to statistical analysis.
BIS (Bispectral Index) is a monitoring method that uses EEG (electroencephalogram) data to measure the depth of anesthesia. It has been used for a long time to assess anesthetic depth. PSI (Patient State Index) is a monitoring method that has become more popular in recent years for measuring the depth of anesthesia. The recommended reference ranges for anesthetic depth are 40-60 for BIS and 25-50 for PSI. The primary objective of this study is to measure the correlation between PSI and BIS values during open-heart surgery.
1 secondary outcome
The secondary objective of this study is to measure the effect of hypothermia, which develops after patients are connected to the cardiopulmonary bypass (CPB) machine during open-heart surgery, on BIS and PSI values that indicate the depth of anesthesia
Time frame: Data will be collected over a 12-month period and subjected to statistical analysis.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Jun 2025.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of BIS-EEG and PSI, run by Kocaeli University at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 29 Jun 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The primary objective of this study is to measure the correlation between BIS and PSI values, which are parameters used to monitor the depth of anesthesia during open-heart surgery. (time frame: Data will be collected over a 12-month period and subjected to statistical analysis.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Jun 2025.