Post Operative Cognitive Dysfunction, Post Operative Delerium
Conditions
Keywords
Post operative delirium, Eye movements, Eye-tracking
Brief summary
Postoperative delirium (POD) is a common complication in older adults undergoing surgery, lacking objective and noninvasive diagnostic methods. This trial aims to evaluate the feasibility and prognostic performance of Eye movements (EM) as a risk biomarker for the development of POD in older patients undergoing moderate- to high-risk surgery. The investigators hypothesize that EM tracking will accurately predict POD, potentially optimizing early intervention and patient outcomes.
Detailed description
This prospective trial evaluates the integration of automated eye movement assessments as a novel, noninvasive risk biomarker for postoperative delirium (POD) in older adults. Upon enrollment, trained clinical staff will collect baseline demographic data and clinical characteristics. Chronic medical burden will be quantified using the Charlson Comorbidity Index (CCI). To establish baseline cognitive function and control for preexisting cognitive impairment, all participants will undergo the Montreal Cognitive Assessment (MoCA). Technical Protocol for Eye Movement Recording Preoperatively, participants will complete an automated eye movement tracking protocol consisting of two distinct paradigms: Prosaccadic Task: Utilized to measure specific ocular motor parameters, including saccadic latency, velocity, and accuracy. Free Visual Exploration Task: Utilized to capture free-gaze metrics and spatial distribution patterns. All eye-tracking data will be recorded using automated software to ensure objectivity and reproducibility. Postoperative Monitoring Following the surgical procedure, patients will be systematically monitored for the development of POD. The Confusion Assessment Method (CAM) will be administered by trained examiners twice daily (morning and evening) for the first three postoperative days (72 hours) to detect and document the incidence and severity of delirium. Statistical and Predictive Objectives The collected data will be analyzed to fulfill three primary scientific objectives: 1. Parameter Association: To identify which specific preoperative eye-tracking metrics (latency, velocity, accuracy, or free-gaze variables) demonstrate a statistically significant association with the incidence of POD. 2. Diagnostic Performance: To calculate the sensitivity and specificity of these distinct preoperative eye movement parameters for predicting POD development. 3. Incremental Predictive Value: To evaluate whether adding preoperative eye-tracking measurements to a standard clinical prediction model (comprising age, sex, CCI, and MoCA scores) significantly improves the model's overall predictive performance and risk stratification capabilities.
Interventions
None listed
Sponsors
University of Chile
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
70 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Patients aged 70 years or older. * Scheduled for moderate- to high-risk elective surgery, defined as a procedure requiring a postoperative hospital stay of at least 3 days. * Able to provide signed, written informed consent.
Exclusion criteria
* Presence of delirium at baseline admission, evaluated via the Confusion Assessment Method (CAM). * Use of neuroleptic/antipsychotic medications within the past 6 months. * Prior history of dementia (including Alzheimer's disease, vascular dementia, or mild cognitive impairment). * History of encephalopathy. * Psychiatric disorders presenting with psychosis. * Brain injury with neurological sequelae (e.g., prior stroke, traumatic brain injury). * Visual acuity is insufficient to complete the automated eye-tracking tasks. * Illiteracy. * Non-Spanish speakers. * Concurrent participation in any other clinical trial.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Incidence of postoperative delirium (POD). | From the day of surgery up to postoperative day 3, patients were assessed twice daily. | The presence or absence of postoperative delirium will be assessed using the Confusion Assessment Method (CAM). Patients will be classified as "POD" or "No POD" based on the CAM diagnostic algorithm. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Preoperative Baseline Cognitive Status | At preoperative baseline (day of surgery or day before). | Total score on the Montreal Cognitive Assessment (MoCA) to determine baseline global cognitive function. The score ranges from 0 to 30, with lower scores indicating greater cognitive impairment. |
| Preoperative Comorbidity Burden | At preoperative baseline (day of surgery or day before) | Score on the Charlson Comorbidity Index (CCI) to quantify the participant's baseline medical comorbidity burden and pre-existing health conditions. |
| Preoperative Saccadic Latency | At preoperative baseline (day of surgery or day before) | The time taken from the appearance of a visual target to the initiation of the participant's saccadic eye movement during the prosaccadic task (milliseconds). |
| Preoperative Saccadic Velocity | At preoperative baseline (day of surgery or day before). | The peak speed of the participant's eye movement when moving towards the visual target during the prosaccadic task (degrees per second). |
| Preoperative Free Viewing Number of Fixations | At preoperative baseline (day of surgery or day before). | The absolute count of discrete gaze fixations made by the participant during the free visual exploration task (number of fixations) |
| Preoperative Free Viewing Saccade Length | At preoperative baseline (day of surgery or day before). | The average spatial distance between fixations in the participant's eye movements during the free visual exploration task (degrees of visual angle). |
| Hospital Length of Stay | Up to 30 days post-surgery. | Total hospital stay from the day of surgery until official hospital discharge. |
| All-Cause Mortality | At 30 days post-surgery. | Total number of participant deaths from any cause, verified via hospital electronic medical records or direct follow-up contact. |
Countries
Chile
Contacts
PRINCIPAL_INVESTIGATORIvan Plaza-Rosales, PhD
University of Chile
Outcome results
None listed