Post-operative Cognitive Dysfunction and the Change of Regional Cerebral Oxygen Saturation in Elderly Patients Undergoing Spinal Surgery

Study Overview
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Brief Summary
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Post operative cognitive dysfunction (POCD) is a well-recognized complication of patients undergoing cardiac surgery. Previous studies reported near-infrared spectroscopy provides information on the occurrence of cerebral desaturation resulted in POCD. But evidence of POCD after general surgery has been lacking. Especially, the prone position is used primarily for surgical access to the posterior spine, if there is any significant lowering of the legs or tilt of the entire table, venous returns may be decrease or augmented accordingly. The purpose of this study was to examine the relationship between POCD and intra-operative cerebral oxygen saturation after spine surgery in elderly patients.

Conditions
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Elderly Patients Undergoing Spinal Surgery

Intervention / Treatment
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* Other: Neurologic and neuropsychologic tests


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: the patient undergoing the lumbar spine surgery in severance hospital Exclusion Criteria: Patients who had previous cerebral disease, dementia, severe problems in hearing and understanding, or who were unable to provide informed consent were excluded.

Ages Eligible for Study
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Minimum Age: 65 Years
Maximum Age: 85 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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Design Details

Primary Purpose: Screening
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: regional cerebral oxygen saturation<br> | Other: Neurologic and neuropsychologic tests<br>* Cognitive functioning was assessed with the following test: Korean Mini-Mental State Examination (K-MMSE) and visuomotor test of D-LOTCA battery. Regional cerebral oxygen saturation was continuously monitored using the INVOS 5100 (somatics,Troy, MI) with bifrontal placement of two sensors before the induction of the anesthesia until the end of operation. Baseline rSO2 was defined as the average saturation value over a 1 min period before induction of general anesthesia, beginning approximately 3 min after the sensors were applied in supine position. After the induction, baseline prone rSO2 was defined over a 5min period after the change of position. There is no intervention were made according to rSO2 values. Physiologic variables including BIS, PaCO2,PaO2, glucose, electrolyte, hematocrit, HR, MAP, and nasopharyngeal temperature were measured every 1 hours during the surgery.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| K-MMSE | preoperative neuropsychological evaluation (the day before the surgery) intraoperative rSO2 data monitoring 3-1. immediate postoperative neuropsychological evaluation (postoperative 4th 7th day) 3-2. remote postoperative neuropsychological evaluation (postoperative 1month) 4. Intraoperative | change of K-MMSE from baseine to 1 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| visuomotor test(D-LOTCA battery) | :Visuomotor test (D-LOTCA battery) Copy Geometric Forms Two Dimensional Model Pegboard Construction Block Design(colored) Reproduction of Puzzle Drawing Clock | measuring for visuomotor test during baseline and 1 month | 
| Regional cerebral oxymetry monitoring | Correlation between rSO2 and POCD The average, left and right absolute rSO2 values were collected every 30 seconds. rSO2 value was recorded as excel data. Absolute rSO2 value and AUT(area under the threshold) send beneath the absolute threshold limits of 40%, 50%, 60% and 20% under the baseline. AUT was calculated based on this formula: AUT (present)=AUT (past)+(rSO2 threshold-rSO2 value)×sample rate cutoff value of rSO2 predictive POCD Correlation of physical value affecting rSO2 and POCD (BIS, PaCO2,PaO2, glucose, electrolyte, hematocrit, HR, MAP, and nasopharyngeal temperature, intraoperative blood loss, amount of intake fluid, total dose of vasopressor) | measuring for Regional cerebral oxymetry monitoring during baseline and 1 month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Post-operative cognitive dysfunction, regional cerebral oxygen saturation, elderly