Brain Monitoring for Surgery

Overseen By Zheng Xie, MD, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Chicago

Must not be taking: Gender-affirming hormones

Disqualifiers: Seizures, Emergency surgery, Allergies, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 2 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 3

Duration: 60-240 minutes

100 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a new method for monitoring brain activity during surgery to determine if it aids in better recovery from anesthesia, with fewer side effects and earlier discharge. The focus is on using the Sedline Brain Function Monitor to guide anesthesia in one group, while the other group will not use the monitor. Researchers aim to discover if men and women respond differently to anesthesia with or without brain monitoring. The study seeks participants with planned surgeries lasting 60 to 240 minutes who are healthy or have mild to severe, but not life-threatening, diseases. As an unphased trial, this study offers a unique opportunity to contribute to innovative research that could enhance surgical recovery for future patients.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but if you are taking gender-affirming hormonal medications, you cannot participate in the study.

What prior data suggests that the Sedline Brain Function Monitor is safe for brain monitoring during surgery?

Studies have shown that the Sedline Brain Function Monitor can help manage anesthesia by reducing the required amount, potentially leading to fewer side effects and faster recovery for patients. However, specific safety information for the Sedline Monitor remains limited.

Although no direct evidence of harm exists, research on similar brain monitors has generally shown them to be safe. It is important to note that the safety information for Sedline is still incomplete. This monitor tracks brain activity during surgery, aiming to enhance the overall surgical experience without adding extra risks. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the Sedline Brain Function Monitor because it offers a new way to guide anesthesia during surgery. Unlike conventional methods that rely on general monitoring and clinician judgment, the Sedline monitor provides real-time data on the brain's activity, potentially allowing for more precise anesthesia management. This could lead to improved patient outcomes by minimizing the risk of over- or under-sedation, which is a common concern with standard anesthesia practices. By offering a more tailored approach to anesthesia, the Sedline monitor could enhance safety and recovery times for patients undergoing surgery.

What evidence suggests that the Sedline Brain Function Monitor is effective for improving recovery during surgery?

Research shows that the Sedline Brain Function Monitor can make anesthesia safer and more efficient. In this trial, participants in the Sedline Monitor Arm will have their anesthesia care guided by the Sedline monitor during the procedure. The monitor tracks brain activity, allowing doctors to adjust anesthesia levels as needed, which can lead to fewer side effects and faster recovery times. Studies have demonstrated that the monitor improves brain monitoring by using a Patient State Index (PSI) to indicate how deeply a patient is sedated. In children, the monitor has been particularly beneficial, enhancing safety and reducing costs. Overall, the Sedline Monitor offers significant advantages in surgical settings. Participants in the Control Arm will receive anesthesia care not guided by the Sedline monitor. ^{4 6 7 8 9}

Who Is on the Research Team?

Zheng Xie, MD, PhD

Principal Investigator

University of Chicago

Are You a Good Fit for This Trial?

This trial is for healthy adults aged 18-45 undergoing planned surgeries lasting 1-4 hours under specific anesthesia, who can consent to participate. It's open to all genders and contraception users but excludes those with allergies to anesthetic agents, seizure history, emergency surgery patients, or those unable to use the Sedline monitor.

Inclusion Criteria

Pregnant women will not be strictly excluded from this study if they meet all other criteria.

Subjects capable of giving informed consent or have an acceptable surrogate capable of giving consent

My surgery is expected to last 1 to 4 hours under certain anesthesia.

Exclusion Criteria

Listed allergies to any commonly used anesthetic agents

My health is severely impaired, making me a high-risk patient for surgery.

I have a history of seizures.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1 day

1 visit (in-person)

Treatment

Participants undergo general anesthesia for surgery with or without the use of the Sedline Brain Function Monitor

60-240 minutes

1 visit (in-person)

Follow-up

Participants are monitored for recovery and satisfaction post-surgery, including a phone call on postoperative day 1

1 day

1 phone call

What Are the Treatments Tested in This Trial?

Interventions

• Sedline Brain Function Monitor

Trial Overview The study tests if monitoring brain activity with the Sedline Brain Function Monitor during anesthesia improves recovery outcomes like earlier discharge and fewer side effects. It also examines gender differences in response to anesthetics with this monitoring.

How Is the Trial Designed?

Group I: Control Arm Active Control 1 Intervention

Conventional method: Anesthesia will not be guided by the Sedline brain function monitor during the procedure.

Group II: Sedline Monitor Arm Active Control 1 Intervention

Anesthesia care guided by Sedline brain function monitor during the procedure.

Sedline Brain Function Monitor is already approved in United States, European Union for the following indications:

Approved in United States as SedLine Sedation Monitor for:

• Monitoring brain activity during anesthesia in adult patients (18 years of age and older)

Approved in European Union as Next Generation SedLine for:

• Monitoring brain activity during anesthesia in adult and pediatric patients (1 year of age and older)

Who Is Running the Clinical Trial?

University of Chicago

Lead Sponsor

Trials

1,086

Recruited

844,000+

Published Research Related to This Trial

A new method for clinical microdialysis has been developed for neurotrauma patients, allowing for easier monitoring of brain metabolism without the need for surgical decompression.

The method was validated postmortem, showing accurate placement of the microdialysis probe, and case reports indicate its potential for future use in non-traumatic brain disorders.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A new screwing device for fixing a microdialysis probe in critical care patients. Kanner, A., Mendelowitsch, A., Langemann, H., et al.[2019]

This study established baseline levels of key biochemical markers in the human brain during wakefulness, anesthesia, and neurosurgery, using microdialysis in nine patients undergoing surgery for benign brain lesions.

Significant increases in glucose, lactate, pyruvate, glycerol, glutamate, and urea levels were observed during anesthesia and surgery, indicating that these markers can reflect physiological changes in the brain during neurointensive care.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Intracerebral microdialysis in clinical practice: baseline values for chemical markers during wakefulness, anesthesia, and neurosurgery. Reinstrup, P., Ståhl, N., Mellergård, P., et al.[2019]

In a case study of a 50-year-old man undergoing open heart surgery, the use of atrial demand pacing led to abnormally high Patient State Index (PSI) values, indicating potential inaccuracies in monitoring anesthesia depth.

The study found that the EEG was contaminated by pacemaker spikes, which caused the PSI to fluctuate significantly, suggesting that anesthesiologists should be cautious when interpreting PSI values in patients with epicardial pacing.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Abnormally high Patient State Index associated with epicardial pacing: a case report. Yonezawa, H., Maeda, T., Takise, Y., et al.[2022]

This study will evaluate the effectiveness of two brain function monitoring devices, the bispectral index (BIS) and SedLine, in assessing the depth of anesthesia in 100 adult patients undergoing elective procedures, using a custom interface to ensure accurate comparisons.

The research aims to identify how well these EEG indices align with clinical assessments of anesthesia depth, while also exploring factors that may cause discrepancies, such as patient age, surgical conditions, and medication effects.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Simultaneous comparison of depth of sedation performance between SedLine and BIS during general anesthesia using custom passive interface hardware: study protocol for a prospective, non-blinded, non-randomized trial. Jones, JH., Nittur, VR., Fleming, N., et al.[2022]

The SedLine® monitor effectively recorded EEG activity in anaesthetized pigs, showing stable values during surgery and significant changes during the emergence period, indicating its potential for monitoring depth of anesthesia.

However, the EEG signals recorded by the SedLine® sensor in pigs do not correspond to the same brain areas as in humans, suggesting that further research is needed to understand species-specific differences in EEG monitoring.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Usability of the SedLine® electroencephalographic monitor of depth of anaesthesia in pigs: a pilot study. Mirra, A., Casoni, D., Barge, P., et al.[2023]

The Patient State Index (PSI) and spectral edge frequency (SEF) increase with patient age during general anesthesia, indicating that older patients may require different monitoring considerations.

The SEDLine monitor has a clinically significant time delay of about 54-55 seconds in responding to changes in anesthesia depth, which is important for anesthetic management and should be taken into account to avoid potential awareness or excessive sedation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Performance of the SEDLine Monitor: Age Dependency and Time Delay. Obert, DP., Schneider, F., Schneider, G., et al.[2023]

A 42-year-old man undergoing elective embolisation for an arteriovenous malformation showed rapid recovery from propofol anaesthesia after neuromuscular block reversal with sugammadex, despite still having significant propofol levels in his system.

The SedLine Brain Function Monitor was effectively used to titrate anaesthetic depth and monitor the patient's rapid arousal, suggesting its utility in managing anaesthesia during procedures.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Rapid arousal from anaesthesia after reversal of deep rocuronium-induced neuromuscular block with sugammadex in a neuroradiological procedure. Giuffrida, M., Ledingham, NS., Machi, P., et al.[2021]

Cerebral microdialysis allows for continuous, real-time monitoring of brain metabolism and cellular damage indicators, which can provide critical information before changes are seen in blood tests or overall body functions.

This technique measures key biochemical variables like glucose, lactate, and glutamate, helping clinicians assess cerebral energy metabolism and potential brain injury more effectively.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cerebral energy metabolism and microdialysis in neurocritical care. Nordström, CH.[2021]

In a study of 10 patients undergoing high flow bypass procedures, increases in extracellular glutamate levels were detected using in-vivo microdialysis, indicating potential ischaemia and correlating with new neurological deficits in some patients.

Routine intra-operative monitoring methods like SSEPs and EEG did not reliably detect ischaemia, highlighting the potential of glutamate measurement as a more effective early warning system for neuronal damage during surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

An increase in extracellular glutamate is a sensitive method of detecting ischaemic neuronal damage during cranial base and cerebrovascular surgery. An in vivo microdialysis study. Mendelowitsch, A., Sekhar, LN., Wright, DC., et al.[2019]

Microdialysis is a highly sensitive technique used to study neurotransmitters and other low molecular weight substances in the brain, allowing researchers to monitor changes in brain chemistry in specific areas like the striatum.

This technique is particularly valuable in awake animals for linking behavioral changes to neurotransmitter activity, and it has clinical applications in monitoring conditions such as ischemic injury and epilepsy, suggesting its growing importance in neurological clinics.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Intracerebral microdialysis: 30 years as a tool for the neuroscientist. Bourne, JA.[2022]

In a study of 33 patients undergoing anesthesia, the updated SedLine® sensor algorithm significantly reduced the incidence of abnormally high Patient State Index (AHPSi) values from 26.7% to 4.2%, indicating improved accuracy in monitoring sedation depth.

The findings suggest that using the updated algorithm, which incorporates Bispectral Index (BIS) values, helps prevent misinterpretation of low-amplitude EEG signals in older patients, enhancing the safety and efficacy of anesthesia management.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Update on the SedLine® algorithm for calculating the Patient State Index of older individuals during general anesthesia: a randomized controlled trial. Obara, S., Oishi, R., Nakano, Y., et al.[2021]

Citations

1. investor.masimo.com investor.masimo.com/news/news-details/2025/New-Study-Finds-Masimo-SedLine-Brain-Function-Monitoring-Offers-Significant-Advantages-During-Pediatric-Anesthesia/default.aspx

New Study Finds Masimo SedLine® Brain Function ... The researchers found that Masimo SedLine helped to make pediatric anesthesia safer, more efficient, and more cost effective.

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10845389/

Assessment of seizure duration and utility of using SedLine ... The SedLine® Brain Function Monitoring system calculates a patient state index (PSI). The PSI scale ranges from 0 to 100, with a number between ...

3. withpower.com withpower.com/trial/phase-surgery-7-2024-c910f

Brain Monitoring for Surgery The SedLine Brain Function Monitor has been shown to help monitor the depth of anesthesia by tracking brain activity, which can assist in adjusting anesthesia ...

4. frontiersin.org frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2023.1084426/full

Changes in SedLine-derived processed ... The depth-of-anesthesia parameter displayed by SedLine is the Next Generation Patient State Index (PSI), a dimensionless index of sedation depth ...

5. biospace.com biospace.com/new-study-finds-that-masimo-sedline-patient-state-index-psi-has-the-potential-to-improve-brain-monitoring-for-patients-sedated-with-dexmedetomidine

New Study Finds That Masimo SedLine® Patient State ... New Study Finds That Masimo SedLine® Patient State Index (PSi) Has the Potential to Improve Brain Monitoring for Patients Sedated with ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC3124903/

Evaluation of the SEDline to improve the safety ... Brain function monitors have improved safety and efficiency in general anesthesia; however, they have not been adequately tested for guiding conscious ...

7. investor.masimo.com investor.masimo.com/news/news-details/2022/Randomized-Controlled-Study-Finds-Masimo-SedLine-Brain-Function-Monitoring-Can-Help-Guide-Anesthesia-in-Children-Undergoing-Minor-Surgery/default.aspx

Randomized Controlled Study Finds Masimo SedLine ... They found that use of SedLine to guide anesthesia reduced sevoflurane requirements and led to a reduced incidence of burst suppression.

8. cdn.clinicaltrials.gov cdn.clinicaltrials.gov/large-docs/82/NCT05051982/Prot_SAP_000.pdf

SedLine EEG-Guided Depth of Anesthesia The primary objective of this study will be to determine whether an anesthetic guided by the Sedline EEG based monitor will reduce the total dosage of ...

9. janesthanalgcritcare.biomedcentral.com janesthanalgcritcare.biomedcentral.com/articles/10.1186/s44158-024-00143-9

Assessment of seizure duration and utility of using SedLine ... The SedLine® Brain Function Monitoring system displays four real-time simultaneous frontal EEG waveforms, and in contrast to Bispectral Index™ ( ...