Postoperative Delirium in Hip Arthroplasty Patients

Study Overview
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Brief Summary
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Identification of specific circulating microRNAs and microemboli formation (diagnosed by TC Doppler) in both delirious groups and nondelirious group will be our primary target. Delirium assessment through standardized questionnaires will be done at baseline (day of the surgery - pre operatory), immediately after surgery (in post anesthesia care unit) and then every 12 hours in Day 1 and Day2 after surgery. The investigators will use linear mixed models to describe the change patterns overtime, and compare differences at each time point. Inflammatory biomarkers will be explored overtime as well. The investigators will also explore age effect on cognitive function - cognitive reserve - based on the score of the cognitive test administered at baseline.

Detailed Description
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Specific circulating microRNA's have been identified in patients with neurological diseases or deficits, and specifically those with neurodegenerative conditions. Furthermore, available evidence primarily in pre-clinical / animal models supports the hypothesis that post-surgical/anesthesia - induced neuroinflammation leads to post-operative cognitive decline or dysfunction. The investigators hypothesize that specific circulating microRNA's involved in the pro-inflammatory response to surgery/anesthesia are a suitable biomarker of Delirium and/or POCD in surgical hip-arthroplasty patients. However, it is also possible that microamboli during the surgical procedure could contribute to these neurologic outcomes. Therefore, in addition to analyzing microRNA levels (our primary target), the investigators propose to monitor cerebral vascular flow during the surgery to possibly identify microambolic events using Transcranial Doppler. Overall, our overarching goal is to identify novel early clinical indicators of cognitive dysfunction (e.g. Delirium and POCD). The study will include preoperative-postoperative trajectory as well as the value of using subjects as self-controls with appropriate longitudinal analyses of cognition. There are many factors that are potential confounders in relation to cognitive decline and incident dementia. There are key characteristics and events: illnesses requiring hospitalization, that could potentially accelerate cognitive decline or worsen clinical dementia rating which anesthetic agents are administered for the surgical procedure intra-operative adverse events (anesthesia/surgery related, cerebral hypoxia, hypotension/hypertension, blood loss) patient factors (age, education, comorbidity) physiologic factors (inflammation,micro-embolization, blood-brain barrier function); perioperative factors (medications, sleep, complications) postoperative factors (rehabilitation, depression, social support)

Official Title
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Postoperative Delirium in Patients Undergoing Hip Arthroplasty

Conditions
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Delirium, Postoperative Complications

Intervention / Treatment
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* Other: miRNA Testing, Microemboli Monitoring, Delirium Assessment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male or female, between 30 and 80 years of age ASA I , II or III Capable and willing to consent Participants literate in English language Exclusion Criteria: ASA IV or V Patients with severe visual or auditory disorder Illiteracy Presence of a clinically diagnosed major psychiatric condition such as bipolar disorder, uncontrolled major depression, schizophrenia Dementia of Alzheimer's type Parkinson disease Multiple Sclerosis (MS) Vascular dementia

Ages Eligible for Study
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Minimum Age: 30 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 |
| --- | --- |
| Hypoactive Delirium - Delirious<br>Hypoactive delirious patients presenting with lethargy and sedation and are slow to respond to questions and demonstrate little spontaneous movement. miRNA Testing, Microemboli Monitoring, Delirium Assessment will be performed | Other: miRNA Testing, Microemboli Monitoring, Delirium Assessment<br>* Delirium assessment questionnaire and blood testing for miRNA will be done for all patients postoperatively, as well as BIS monitoring during surgery. The three arms of the study indicate the allocation of each patient based on their delirium presentation (hypoactive, hyperactive, or none).<br>|
| Hyperactive Delirium - Delirious<br>Hyperactive delirious patients presenting with restlessness, agitation, hyper vigilance, and occaionally hallucinations. miRNA Testing, Microemboli Monitoring, Delirium Assessment will be performed | Other: miRNA Testing, Microemboli Monitoring, Delirium Assessment<br>* Delirium assessment questionnaire and blood testing for miRNA will be done for all patients postoperatively, as well as BIS monitoring during surgery. The three arms of the study indicate the allocation of each patient based on their delirium presentation (hypoactive, hyperactive, or none).<br>|
| No Delirium - Nondelirious<br>Patients not presenting any symptoms of hypoactive or hyperactive postoperative delirium. miRNA Testing, Microemboli Monitoring, Delirium Assessment will be performed | Other: miRNA Testing, Microemboli Monitoring, Delirium Assessment<br>* Delirium assessment questionnaire and blood testing for miRNA will be done for all patients postoperatively, as well as BIS monitoring during surgery. The three arms of the study indicate the allocation of each patient based on their delirium presentation (hypoactive, hyperactive, or none).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Identification of specific circulating microRNAs in post operative delirium patients | Identification of specific circulating microRNAs and microemboli formation (diagnosed by TC Doppler) in both delirious groups and nondelirious group will be our primary target. Our overarching goal is to identify novel early clinical indicators of cognitive dysfunction (e.g. Delirium and POCD) | Baseline, perioperatively and during post operative hospitalization (Day 1 and Day 2 post surgery) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Age effects on cognitive function (cognitive reserve) | We will explore age effect on cognitive function (cognitive reserve), based on the baselin cognitive assessment score. | Baseline |