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ElectroencephalogramNCT06394778

Electroencephalogram Characteristics of Surgical Anesthetized Patients and Postoperative Dilirium

An observational study of Electroencephalogram and Postoperative Delirium (POD), run by First Affiliated Hospital of Zhejiang University at 1 site in China.

Enrolling by invitation

Enrolling by invitation. The study team selects and invites participants, usually from an existing group of patients.

Sites and contacts
Official record
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Trial summary

Objective: To construct a perioperative EEG database for elderly patients under general anesthesia and to explore the relationship between their EEG spectrum characteristics and the occurrence and severity of postoperative delirium. Read more about this study

Who is it for?
Ages 60 years and older
What is being tested?
Delirium test scale:3D-CAM
How many people
375 participants
Where
1 siteChina
Study dates
13 May 2024to 15 Apr 2027
How long will I take part?
5 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 60 years and older
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Study population: Elderly patients undergoing elective orthopedic joint replacement or spinal surgery

Who may be able to join

  • Patients aged ≥ 60 years, scheduled for orthopedic joint replacement or spinal surgery, ASA grade I-III, expected surgery time ≥ 2 hours, and able to provide written informed consent.

Who cannot join

  • Patients with central nervous system diseases or mental disorders;
  • patients with severe systemic diseases such as cardiopulmonary, liver and kidney dysfunction, coagulation dysfunction, etc.;
  • patients who frequently use psychotropic drugs, opioids or corticosteroids;
  • patients with a history of intraoperative awareness;
  • patients who are unable to complete preoperative delirium screening due to severe blindness, deafness, illiteracy or Mandarin speaking;
  • patients who are expected to undergo a second operation within 7 days.

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

China1 site
  • The First Affiliated Hospital, Zhejiang University, School of Medicine

    Hangzhou, Zhejiang, 310003

Other trials in China

About this study

Official title: Electroencephalogram Characteristics of Surgical Anesthetized Patients and Their Correlation With Postoperative Delirium

Objective: To construct a perioperative EEG database for elderly patients under general anesthesia and to explore the relationship between their EEG spectrum characteristics and the occurrence and severity of postoperative delirium. Content: This study aims to investigate elderly patients undergoing elective orthopedic surgery under general anesthesia with endotracheal intubation, analyze the changes in the perioperative EEG spectrum and its correlation with the occurrence of postoperative delirium, and explore the relationship between perioperative EEG changes and the occurrence of postoperative delirium. Methods: Patients aged 60 years or older who were scheduled to undergo orthopedic joint replacement or spinal surgery and had a hospital stay of more than 2 days were selected. All patients underwent MMSE and 3D-CAM assessment before surgery. Before anesthesia induction, anesthesia depth monitoring electrodes were placed on the patient\'s occipital or frontal temporal region, and EEGs were collected in awake and quiet states, under general anesthesia, and during anesthesia recovery. In the PACU, the score was calculated based on the CAM-ICU scale. The patients were assessed with the 3D-CAM scale for awakening once a day at 15:00-20:00 the day before surgery, and twice a day at 9:00-11:00 and 15:00-20:00 during 1-5 days after surgery, or at any time when obvious delirium symptoms appeared, unless discharged from the hospital or taking sedatives (RASS\<-3). Ten minutes after the assessment, the occipital EEG was monitored when the patient was conscious and quiet, or when obvious delirium appeared. According to the test results of the 3D-CAM scale, it was determined whether the patient had postoperative delirium, and the patients were divided into the delirium group and the non-delirium group. The EEG characteristics of the two groups of patients were analyzed before, during, and after surgery. Research significance: The results of this study can provide objective indicators and theoretical basis for monitoring and diagnosing the occurrence and development of POD, which can help clinicians to identify patients with increased risk of delirium at an early stage, adjust the plan in time, and change the triggering risk factors of POD.

Read the detailed description

Preoperative cognitive and delirium assessment:

MMSE scale assesses the patient\'s preoperative cognitive function status: the total score is 30 points, the higher the score, the better the cognitive function. Considering the impact of education level on MMSE assessment, combined with my country\'s actual situation and previous studies, we set the assessment criteria for illiterate or most primary and junior high school education levels to ≤17, ≤20, and ≤24, respectively. Individuals below the corresponding standards are considered to have cognitive impairment before surgery.

Preoperative 3D-CAM baseline value for delirium assessment: patients were assessed for delirium using the 3-minute rapid mental confusion assessment method (3D-CAM) between 15:00 and 20:00 the day before surgery.

Postoperative delirium assessment:

During the postoperative PACU period, the score was calculated based on the CAM-ICU scale; 1-5 days after surgery, patients underwent 3D-CAM assessment twice a day at 9:00-11:00 and 15:00-20:00, or at any time when obvious delirium symptoms appeared, unless discharged or taking sedatives (RASS\<-3).

Being tested
Delirium test scale:3D-CAM
Keywords
Single-center, prospective, observational, case-control study
Medical subject headings
Emergence Delirium

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Delirium test scale:3D-CAMDiagnostic test

    The 3D-CAM is a 3-minute delirium assessment that is also based upon the CAM algorithm and has four features: (1) altered mental status/fluctuating course, (2) inattention, (3) altered level of consciousness, and (4) disorganized thinking.

Study groups in NCT06394778
Study groupRoleWhat they receive
Delirium groupIf the patient develops delirium after surgery, he/she is in the delirium group
Receives: Diagnostic Test: Delirium test scale:3D-CAM
Non delirium groupIf the patient does not experience delirium after surgery, it is considered as the non-delirium group
Receives: Diagnostic Test: Delirium test scale:3D-CAM

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Correlation between perioperative EEG spectral changes and postoperative delirium

    Characteristic changes of EEG spectral changes in patients with POD before, during, and after surgery

    Measured: 2 years

  2. Incidence of POD

    The proportion of POD occurrence

    Measured: 1 years

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted1 May 2024
  2. Study start13 May 2024
  3. Primary completion30 Sep 2026 (estimated)
  4. Study completion15 Apr 2027 (estimated)

Resources

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
Case-control
Time perspective
Prospective
Enrolment
375 participants (estimated)
Target duration
5 Days
IDs, dates and publications
ClinicalTrials.gov ID
NCT06394778
Sponsor's protocol ID
IIT20240135B-R1
Status last verified
Aug 2025
First submitted
29 Apr 2024
Last updated
12 Jan 2026
Results posted
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Publications

  • Ravi B, Pincus D, Choi S, Jenkinson R, Wasserstein DN, Redelmeier DA. Association of Duration of Surgery With Postoperative Delirium Among Patients Receiving Hip Fracture Repair. JAMA Netw Open. 2019 Feb 1;2(2):e190111. doi: 10.1001/jamanetworkopen.2019.0111.

    PubMed 30794305
  • Gan S, Yu Y, Wu J, Tang X, Zheng Y, Wang M, Zhu S. Preoperative assessment of cognitive function and risk assessment of cognitive impairment in elderly patients with orthopedics: a cross-sectional study. BMC Anesthesiol. 2020 Aug 1;20(1):189. doi: 10.1186/s12871-020-01096-6.

    PubMed 32738902
  • Kinoshita H, Saito J, Kushikata T, Oyama T, Takekawa D, Hashiba E, Sawa T, Hirota K. The Perioperative Frontal Relative Ratio of the Alpha Power of Electroencephalography for Predicting Postoperative Delirium After Highly Invasive Surgery: A Prospective Observational Study. Anesth Analg. 2023 Dec 1;137(6):1279-1288. doi: 10.1213/ANE.0000000000006424. Epub 2023 Mar 14.

    PubMed 36917508
  • Koch S, Windmann V, Chakravarty S, Kruppa J, Yurek F, Brown EN, Winterer G, Spies C; BioCog Study Group. Perioperative Electroencephalogram Spectral Dynamics Related to Postoperative Delirium in Older Patients. Anesth Analg. 2021 Dec 1;133(6):1598-1607. doi: 10.1213/ANE.0000000000005668.

    PubMed 34591807
  • Hesse S, Kreuzer M, Hight D, Gaskell A, Devari P, Singh D, Taylor NB, Whalin MK, Lee S, Sleigh JW, Garcia PS. Association of electroencephalogram trajectories during emergence from anaesthesia with delirium in the postanaesthesia care unit: an early sign of postoperative complications. Br J Anaesth. 2019 May;122(5):622-634. doi: 10.1016/j.bja.2018.09.016. Epub 2018 Oct 25.

    PubMed 30915984
  • Lutz R, Muller C, Dragovic S, Schneider F, Ribbe K, Anders M, Schmid S, Garcia PS, Schneider G, Kreuzer M, Kratzer S. The absence of dominant alpha-oscillatory EEG activity during emergence from delta-dominant anesthesia predicts neurocognitive impairment- results from a prospective observational trial. J Clin Anesth. 2022 Nov;82:110949. doi: 10.1016/j.jclinane.2022.110949. Epub 2022 Aug 29.

    PubMed 36049381
  • Boord MS, Moezzi B, Davis D, Ross TJ, Coussens S, Psaltis PJ, Bourke A, Keage HAD. Investigating how electroencephalogram measures associate with delirium: A systematic review. Clin Neurophysiol. 2021 Jan;132(1):246-257. doi: 10.1016/j.clinph.2020.09.009. Epub 2020 Oct 1.

    PubMed 33069620
  • Kassie GM, Nguyen TA, Kalisch Ellett LM, Pratt NL, Roughead EE. Preoperative medication use and postoperative delirium: a systematic review. BMC Geriatr. 2017 Dec 29;17(1):298. doi: 10.1186/s12877-017-0695-x.

    PubMed 29284416
  • Kaiser HA, Peus M, Luedi MM, Lersch F, Krejci V, Reineke D, Sleigh J, Hight D. Frontal electroencephalogram reveals emergence-like brain activity occurring during transition periods in cardiac surgery. Br J Anaesth. 2020 Sep;125(3):291-297. doi: 10.1016/j.bja.2020.05.064. Epub 2020 Jul 15.

    PubMed 32682555
  • Purdon PL, Sampson A, Pavone KJ, Brown EN. Clinical Electroencephalography for Anesthesiologists: Part I: Background and Basic Signatures. Anesthesiology. 2015 Oct;123(4):937-60. doi: 10.1097/ALN.0000000000000841.

    PubMed 26275092
  • Tsai MC, Chou SY, Tsai CS, Hung TH, Su JA. Comparison of consecutive periods of 1-, 2-, and 3-year mortality of geriatric inpatients with delirium, dementia, and depression in a consultation-liaison service. Int J Psychiatry Med. 2013;45(1):45-57. doi: 10.2190/PM.45.1.d.

    PubMed 23805603
  • Jabbar F, Leonard M, Meehan K, O'Connor M, Cronin C, Reynolds P, Meaney AM, Meagher D. Neuropsychiatric and cognitive profile of patients with DSM-IV delirium referred to an old age psychiatry consultation-liaison service. Int Psychogeriatr. 2011 Sep;23(7):1167-74. doi: 10.1017/S1041610210002383. Epub 2011 Jan 21.

    PubMed 21251353
  • Blazer DG, van Nieuwenhuizen AO. Evidence for the diagnostic criteria of delirium: an update. Curr Opin Psychiatry. 2012 May;25(3):239-43. doi: 10.1097/YCO.0b013e3283523ce8.

    PubMed 22449764

Questions about this trial

What is this clinical trial studying?

An observational study of Electroencephalogram and Postoperative Delirium (POD), run by First Affiliated Hospital of Zhejiang University at 1 site in China.

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 1 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: enrolling by invitation, as of the sponsor's last update on 12 Jan 2026. 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 China. 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?

Correlation between perioperative EEG spectral changes and postoperative delirium (time frame: 2 years). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT06394778, which also lists 13 linked publications.

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 12 Jan 2026.

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