Detection and Neurological Impact of CerebroVascular Events In Noncardiac Surgery PatIents: A COhort EvaluatioN

Study Overview
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Brief Summary
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The NeuroVISION Study will characterize the incidence, impact, and risk factors of covert stroke in adults undergoing noncardiac surgery. We will determine the incidence of acute covert stroke using an MRI study of the brain in the days following noncardiac surgery. We will characterize the epidemiology and the impact of covert stroke in patients undergoing noncardiac surgery, and its association with cerebral deoxygenation.

Detailed Description
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At the University of Wisconsin a planned sub study of NeuroVISION is being conducted aiming to enroll 100 patients with additional cognitive testing, MRI sequences and a preoperative MRI scan. At Hamilton Juravinski Hospital, Hamilton General Hospital, Auckland City Hospital and Prince of Wales Hospital a planned sub study of NeuroVISION (PAFS - Perioperative Atrial Fibrillation and Postoperative Stroke) is being conducted aiming to enroll 400 participants. The purpose of this sub-study is to determine the prevalence of AF(Atrial Fibrillation) before surgery (i.e. background AF), as well of the incidence of AF after surgery using the Icentia CardioSTAT patch-like single lead heart rhythm monitor.

Official Title
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Detection and Neurological Impact of CerebroVascular Events In Noncardiac Surgery PatIents: A COhort EvaluatioN

Conditions
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Covert Postoperative Stroke

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥65 years old An anticipated hospital stay of at least 2 days after elective noncardiac surgery that occurs under general or neuraxial anesthesia Written informed consent for potential participation prior to noncardiac surgery Exclusion Criteria: Contraindication to MRI (e.g. implanted devices not safe for MRI studies, claustrophobia) Unable or unwilling to attend the follow-up appointments Documented history of dementia Residing in a nursing home Undergoing carotid artery surgery or intracranial surgery Unable to complete neurocognitive testing due to language, vision or hearing impairment Unable to communicate with the research staff due to language barriers Patients who do not undergo their research MRI study after surgery Patients who do not complete a baseline MoCA questionnaire Patients who suffer an acute overt clinical stroke after the index surgery, but before their research MR study Previously enrolled in the NeuroVISION Study.

Ages Eligible for Study
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Minimum Age: 65 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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative cognitive dysfunction | Our primary objective is to characterize the impact of postoperative covert stroke on neurocognitive function 1 year after elective noncardiac surgery, as measured by a decrease of two or more points on the Montreal Cognitive Assessment (MoCA) scale from preoperative baseline test to the 1-year follow-up. | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of acute postoperative covert stroke | We will detect acute postoperative covert stroke using an MR study of the brain that will be performed between postoperative days 2 and 9. | 30 days | 
| Clinical 30-day outcomes (rated yes/no) | Overt stroke, transient ischemic attack, death, myocardial infarction, myocardial injury after noncardiac surgery, nonfatal cardiac arrest, major adverse cardiovascular events, cardiac revascularization procedures, bleeding, new atrial fibrillation, hypotension, congestive heart failure, new acute renal failure, infection and sepsis | 30 days | 
| Clinical 1-year outcomes (rated yes/no) | Overt stroke, transient ischemic attack, death, myocardial infarction, nonfatal cardiac arrest, major adverse cardiovascular events (composite), congestive heart failure, new acute renal failure, dementia and mild cognitive impairment | 1 year | 
| Postoperative delirium | Delirium will be measured using the Cognitive Assessment Method (CAM). | 30 days | 
| Physical function after surgery as assessed using the Modified Rankin Scale | Physical function will be measured using the Modified Rankin Scale. The Modified Rankin Scale is a commonly used scale for measuring the degree of disability or dependence in the daily activities of people. The scale runs from 0-6, running from perfect health without symptoms to death. A higher score is worse. | 30 days and 1 year | 
| Physical function after surgery as assessed using the Lawton Instrumental Activities of Daily Living (iADL) Scale | Physical function will be measured using the Lawton Instrumental Activities of Daily Living (iADL) Scale. The Lawton Instrumental Activities of Daily Living Scale refers to people's daily self-care activities. It consists of 8 activities. A lower score is worse. | 30 days and 1 year | 
| Quality of life after surgery | We will use the EQ-5D questionnaire to assess the patients' health-related quality of life. EQ-5D is a standardized instrument developed by the EuroQol Group as a measure of health-related quality of life. The first part contains the EQ-5D descriptive system, comprising of 5 questions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. A higher score is worse. The second part is a vertical, visual analogue scale with the end-points of best imaginable health state and worst imaginable health state. Scale runs from 0 to 100. A lower score is worse. | 30 days and 1 year | 
| Depressive symptoms after surgery | We will use the 5-question version of the Geriatric Depression Scale (GDS-5) to measure depressive symptoms. The 5-question version of the Geriatric Depression Scale scoring will be from 0 to 5. The higher values indicate increasing depressive symptoms. | 30 days and 1 year |