Postoperative Cognitive Function and EEG

Study Overview
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Brief Summary
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In the elderly patients undergoing elective non-cardiac major surgery, the differences of EEG parameters between those with and without postoperative cognitive dysfunction were observed to determine the characteristic changes of EEG parameters related to postoperative cognitive dysfunction

Official Title
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Correlation Between Postoperative Cognitive Function and EEG Parameters in Elderly Patients Undergoing Non-cardiac Major Surgery : Multi-center, Prospective, Observational Study

Conditions
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Aging, Postoperative Cognitive Dysfunction, EEG With Periodic Abnormalities

Intervention / Treatment
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* Other: EEG(Electroencephalogram) change


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: aged 65 and above non-cardiac surgery under general anesthesia; American Society of Anesthesiology(ASA) classification I- II Patients aged 18-40 years old are set as background Exclusion Criteria: patients with central nervous system diseases and mental diseases preoperative minimal mental status examination(MMSE) score<24; ASA status III or higher 3) those who have received less than 5 years of education since entering primary school; 4) history of sedatives or antidepressants use; 5) existed or anticipated alcohol or drug abuse(over 40°c and over 100ml per day for the past 3 months); 6) history of surgery within the previous year; 7) those with severe visual or hearing impairment; 8) those participated in other clinical studies within last 3 months;

Ages Eligible for Study
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Minimum Age: 65 Years
Maximum Age: 100 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 |
| --- | --- |
| with postoperative cognitive dysfunction<br> | Other: EEG(Electroencephalogram) change<br>* patients are found to have characteristic EEG change<br>|
| without postoperative dysfunction<br> | Other: EEG(Electroencephalogram) change<br>* patients are found to have characteristic EEG change<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The difference of delta wave miss rate between patients with or without cognitive dysfunction by 1 day after surgery | The difference (OR) between the miss rate of delta wave in patients with and without cognitive function change 1 day after operation. | from end of surgery to 1 day after surgery | 
| The difference of spindle miss rate between patients with or without cognitive dysfunction by 1day after surgery | The difference (OR) between the miss rate of spindle in patients with and without cognitive function change 1 day after operation. | from end of surgery to 1 day after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The difference of delta wave miss rate between patients with or without cognitive dysfunction by 3 days after surgery |  | from end of surgery to 3 day after surgery | 
| The difference of spindle miss rate between patients with or without cognitive dysfunction by 3 days after surgery |  | from end of surgery to 3 days after surgery | 
| The difference of burst suppression rate between patients with or without cognitive dysfunction by 3 days after surgery |  | from end of surgery to 3 days after surgery | 
| correlation of delta wave miss rate and incidence of postoperative cognitive dysfunction by 1 day after surgery |  | from end of surgery to 1 day after surgery | 
| correlation of delta wave miss rate and incidence of postoperative cognitive dysfunction by 3 days after surgery |  | from end of surgery to 3 days after surgery | 
| correlation of spindle miss rate and incidence of postoperative cognitive dysfunction by 1d after surgery |  | from end of surgery to 1d after surgery | 
| correlation of spindle miss rate and incidence of postoperative cognitive dysfunction by 3 days after surgery |  | from end of surgery to 3 days after surgery | 
| correlation of burst suppression rate and incidence of postoperative cognitive dysfunction by 1 day after surgery |  | from end of surgery to 1 day after surgery | 
| correlation of burst suppression rate and incidence of postoperative cognitive dysfunction by 3 days after surgery |  | from end of surgery to 3 days after surgery | 
| correlation of burst suppression rate and incidence of death by 30 days after surgery |  | from end of surgery to 30 days after surgery | 
| correlation of delta wave miss rate and incidence of death by 30 days after surgery |  | from end of surgery to 30 days after surgery | 
| correlation of spindle miss rate and incidence of death by 30 days after surgery |  | from end of surgery to 30 days after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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noncardiac surgery, elderly patients, postoperative cognitive dysfunction, Electroencephalogram