Postoperative Neuroinflammation and Cognitive Dysfunction After Abdominal Surgery

Study Overview
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Brief Summary
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The main purpose of this study is to assess the induction of neuroinflammation in brain regions of interest for learning and memory in adult patients undergoing urological surgery under general anesthesia

Detailed Description
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The investigators aim to study immune cell activation as a biomarker for neuroinflammation using the cell specific [11C]PBR28 probe as detected by PET imaging techniques.

Conditions
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Anesthesia, Surgery, Neurogenic Inflammation, Cognitive Disorders

Intervention / Treatment
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* Radiation: Positron emission tomography (PET) using [11C]PBR28


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients 60-75 years of age. American Society for Anesthesiologist' criteria (ASA) physical status I-III Lower abdominal surgery (hysterectomy/prostatectomy) under general anaesthesia Obtained consent within 3 months before execution of the study. Exclusion Criteria: Patient's refusal to participate in the trial Ongoing smoking, snuff or other nicotine compound treatment Disabling neuropsychiatrical disorder (a Mini mental State Examination (MMSE) score ≤ 24, diagnosis of dementia, Mb Alzheimer, Mb Parkinson, schizophrenia, or mental depression) or other signs of significant cognitive decline. History of stroke with neurological sequelae Surgical procedure scheduled for regional anaesthesia. Severe cardia and/or renal and/or hepatic impairment. Coagulopathy. Terminal phase of a chronic disease. Patient on steroidal or non-steroidal anti-inflammatory drugs. Admission B-Glucose > 15 mmol/litre or poorly controlled diabetes mellitus. Presumed uncooperativeness or legal incapacity. Preoperative or later postoperative B-hemoglobin < 90 g/L.

Ages Eligible for Study
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Minimum Age: 60 Years
Maximum Age: 75 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: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Positron emission tomography (PET)<br>Positron emission tomography (PET) using [11C]PBR28 | Radiation: Positron emission tomography (PET) using [11C]PBR28<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Binding of the PET probe [11C]PBR28 | PET imaging of brain regions of relevance for memory and learning will be compared between the pre- and postoperative states. | Preoperatively, once at postoperative day 2-5 and after 3 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cognitive testing | Postoperative cognitive test battery according to the ISPOCD protocol, see Moller JT et al, Lancet 1998. | Preoperatively and after 3 month | 
| Inflammatory biomarkers | Inflammatory biomarkers and genetic analysis of inflammatory biomarkers in blood. | Preoperatively, once at postoperative day 2-5 and after 3 month, i.e. at the same time as the PET investigation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Neuroinflammation, Postoperative cognitive dysfunction