Correlation Between Perioperative EEG Features and Delirium After General Anesthesia

Study Overview
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Brief Summary
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The goal of this observational study is to compare the perioperative EEG characteristics and the incidence of short-term cognitive dysfunction in patients with postoperative delirium and non-postoperative delirium after elderly (> 65 years old) patients undergoing major gastrointestinal surgery under general anesthesia. The main question it aims to answer are: • The correlation between postoperative cognitive dysfunction and postoperative EEG features was evaluated.• To analyze the correlation between EEG characteristics and clinical risk factors of delirium after major abdominal gastrointestinal surgery under general anesthesia in elderly patients.Participants will collect EEG before and after operation and collect the incidence of postoperative cognitive function to explore the mechanism of postoperative delirium and predict postoperative cognitive dysfunction.

Official Title
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The Second Affiliated Hospital of Nanchang University

Conditions
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Perioperative Period, Anesthetic, Postoperative Cognitive Dysfunction, Postoperative Delirium

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Education level in primary school or above; Age ≥65 years old, gender is not limited; Good communication ability, language expression ability, mental state and consciousness state; Preoperative simple mental state scale score ≥27 points; no history of craniocerebral diseases; For patients who plan to choose abdominal surgery under general anesthesia, the operation time is expected to be about 2h-4h; ASA anesthesia grade I   III; No general anesthesia contraindications; Sign informed consent voluntarily; Exclusion Criteria: Relative contraindications of general anesthesia: patients with serious heart and lung function diseases, drug allergy history, etc. Patients with a history of mental illness or long-term psychiatric drugs (dementia, schizophrenia), chronic analgesic drug use history, alcoholism history and cognitive dysfunction; any cerebrovascular accident occurred within 3 months, such as stroke, transient ischemic attack (TIA), etc. Diabetic patients with severe diabetic complications (diabetic ketoacidosis, hyperosmolar coma, various infections, macrovascular disease, diabetic nephropathy); Chronic hypoxia and carbon dioxide storage, such as chronic obstructive emphysema; a long history of alcohol abuse; Unable to cooperate to complete the test, the patient or family rejected the participant.

Ages Eligible for Study
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Minimum Age: 65 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| delirium<br>Patients present with delirium within 7 days after general anesthesia | |
| non delirium<br>The patient did not develop delirium for 7 days after general anesthesia | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| wave time-frequency analysis | The characteristics of four kinds of brain wave α, β ,δ and θ were analyzed by professional EEG analysis software | one day before surgery, 7-10 days after surgery | 
| P300 latency and peak changes | The feature analysis of event-related potentials was carried out through professional EEG analysis software | one day before surgery, 7-10 days after surgery | 
| EEG event-related potential accuracy and response time | The accuracy of task EEG was analyzed statistically by using professional EEG analysis software | one day before surgery, 7-10 days after surgery | 
| Incidence of postoperative short-term cognitive dysfunction | A telephone return visit was conducted on patients using the Revised Cognitive Function Telephone Questionnaire (TICS-M) at 1, 3, and 6 months after discharge.The total score was less than 28 points, which was considered as cognitive impairment. | postoperative 1,3,6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Systolic pressure | just entering the operating room, immediately after intubation, every 5 minutes after intubation until the patient leaves the operating room. | perioperative period | 
| Diastolic pressure | just entering the operating room, immediately after intubation, every 5 minutes after intubation until the patient leaves the operating room. | perioperative period | 
| Mean pressure | just entering the operating room, immediately after intubation, every 5 minutes after intubation until the patient leaves the operating room. | perioperative period | 
| Heart rate | just entering the operating room, immediately after intubation, every 5 minutes after intubation until the patient leaves the operating room. | perioperative period | 
| Maximum postoperative C-reactive protein (CRP) | Only the highest CRP values detected in the normal course of gastrointestinal surgery are collected, and no additional blood sampling or interventions are performed | Up to 1 month after surgery | 
| Minimum postoperative albumin | Only the lowest albumin values detected in the normal course of gastrointestinal surgery are collected, and no additional blood sampling or interventions are performed | Up to 1 month after surgery | 
| Postoperative pain | The degree of postoperative pain was assessed using the Numerical Rating Scale (NRS). The pain level increased sequentially from 0-10 | 1, 3, and 7 days after surgery | 
| Complication | All the perioperative complications are recorded | During the perioperative period, up to 1 month after surgery | 
| Length of hospitalization | The total number of days the patient spent at the hospital for the current consultation | After the patient is discharged from the hospital, average 1 month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Perioperative period, Anesthetics, Postoperative Cognitive Dysfunction, postoperative delirium