Dynamic Multimodal Delirium Warning After Cardiac Surgery (DEW-POD)

July 6, 2026 updated by: Jingyuan,Xu, Southeast University, China

A Dynamic Early Warning System for Postoperative Delirium After Cardiac Surgery Integrating EEG, Cerebral Oxygenation, Hemodynamic Physiology, and Clinical Risk Factors

After heart surgery, up to half of all patients may develop a state of sudden confusion called postoperative delirium. This condition can lead to longer time on a breathing machine, extended stays in the intensive care unit (ICU), and a slower overall recovery. Currently, doctors have no reliable way to predict delirium early enough to take preventive action. This study aims to build a computer-based early warning system. The system will combine continuous, real-time measurements of brain waves (EEG), the oxygen level in the brain, and heart and blood pressure function. It will also include information about each patient's health status. By analyzing all of these signals together, the model is designed to give an alert 1 to 6 hours before delirium might start, giving the care team a window of time to intervene. The study will take place in the ICU at Zhongda Hospital, Southeast University. Adults between 18 and 80 years old who are admitted to the ICU after heart surgery will be invited to participate. All patients will receive the usual standard of care; the study does not test any new treatment. Participation means the investigators will continuously record the brain, oxygen, and heart signals that are already being monitored, and a researcher will regularly assess the patient's thinking and alertness with a simple bedside check.

Study Overview

Status

Not yet recruiting

Conditions

Detailed Description

Postoperative delirium (POD) following cardiac surgery has an incidence of 20-50% and is associated with prolonged mechanical ventilation, extended ICU and hospital stay, and increased mortality. Its pathophysiology involves a complex interplay of cerebral hypoperfusion, neuroinflammation, blood-brain barrier disruption, and neurotransmitter imbalances-a "multiple-hit" model. Current clinical assessment relies on static risk stratification or post-hoc diagnostic tools , which lack the dynamic, pre-symptomatic warning capability needed for timely intervention. The increasing availability of multimodal ICU monitoring (EEG, near-infrared spectroscopy, invasive hemodynamics) and advanced time-series deep learning provides an unprecedented opportunity to capture the evolution of physiological uncoupling before the clinical manifestation of delirium.

Objective: This study aims to develop and validate a multimodal deep learning model that fuses continuous central electrophysiology (frontal EEG), regional cerebral oxygen saturation (rScO₂), macro-hemodynamic parameters, and clinical static/dynamic risk factors to provide a dynamic early warning of POD 1-6 hours in advance.

Study Design: This is a single-center, prospective, observational cohort study. Setting and Population: The study will enroll consecutive adult patients (18-80 years) admitted to the Department of Critical Care Medicine at Zhongda Hospital, Southeast University, after cardiac surgery (CABG, valve repair/replacement, major aortic surgery, or combined procedures) between May 1, 2026 and December 30, 2027. All eligible patients must have multimodal monitoring including continuous EEG, bilateral frontal rScO₂, and invasive arterial blood pressure, and must provide informed consent.

Key Exclusion Criteria: Pre-existing dementia, psychiatric illness or long-term antipsychotic use precluding accurate delirium assessment; severe hepatic (Child-Pugh C) or renal insufficiency (eGFR <30 mL/min/1.73 m²); significant brain injury or seizure history; inability to obtain adequate signal quality; expected death within 24 hours.

Data Collection and Monitoring: Data will be captured at multiple time windows: preoperative baseline, intraoperative period, and postoperative time points (immediately upon ICU arrival, 6h, 24h, 48h, and at the moment delirium is first detected). Preoperative phenotyping includes demographics, MoCA, Clinical Frailty Scale, and EuroSCORE II. Continuous EEG features (power spectral density, burst suppression ratio, complexity indices) and rScO₂ (baseline, desaturation events >20%, autoregulation index COx) will be recorded. Hemodynamic variables include heart rate, beat-to-beat blood pressure variability, and, where available, derived cardiac output metrics. Comprehensive clinical data (laboratory values, sedation/analgesic dosing, vasoactive-inotropic score, mechanical ventilation parameters, and SOFA/APACHE II scores) will be collected concurrently.

Delirium Assessment: Trained research staff will assess delirium using the Confusion Assessment Method for the ICU (CAM-ICU) in conjunction with the Richmond Agitation-Sedation Scale (RASS). Assessments occur at baseline, postoperatively when the patient is awake, and at scheduled intervals, with documentation of first onset, duration, and subtype (hyperactive, hypoactive, mixed).

Model Development and Analysis: All signals will be time-aligned to construct a high-resolution multimodal time-series dataset. The primary predictive model will be based on a Transformer or Long Short-Term Memory (LSTM) architecture employing a sliding window approach (e.g., input: preceding 2 hours; output: predicted delirium risk in the next 1-6 hours). The dataset will be split into training, validation, and test sets (7:1.5:1.5). Primary performance metrics are area under the receiver operating characteristic curve (AUC), sensitivity, specificity, positive/negative predictive values, and the achievable warning lead time. Model interpretability will be explored using SHAP or attention weight analysis. The added value of multimodal fusion will be quantified by comparing the full model against unimodal baselines (clinical data only, EEG only, or rScO₂ only).

Outcomes: The primary outcome is the occurrence of POD. Secondary outcomes include duration of mechanical ventilation, ICU length of stay, and hospital length of stay.

Significance: By delineating the temporal trajectories of EEG, cerebral oxygenation, and systemic hemodynamics preceding delirium, this study will provide new pathophysiological insights into the "cerebral perfusion-metabolism-electrical activity" uncoupling hypothesis and deliver a clinically implementable early warning framework to enable proactive brain-directed interventions.

Study Type

Observational

Enrollment (Estimated)

200

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Probability Sample

Study Population

The study population consists of adult patients after cardiac surgery admitted to the Department of Critical Care Medicine, Zhongda Hospital, Southeast University, from May 1, 2026 to December 30, 2027.

Description

Inclusion Criteria:

  1. Adult patients (18-80 years) admitted to the Department of Critical Care Medicine.
  2. Underwent cardiac surgery.
  3. Under multimodal monitoring (including EEG, cerebral oximetry, and invasive arterial blood pressure).
  4. Signed informed consent.

Exclusion Criteria:

  1. Pre-existing dementia, history of psychiatric disorders, or long-term use of antipsychotic medications, preventing accurate assessment of delirium.
  2. Preoperative severe hepatic or renal insufficiency (Child-Pugh Class C or eGFR <30 mL/min/1.73 m²).
  3. Severe craniocerebral injury, intracranial space-occupying lesion, or history of epilepsy.
  4. Inability to obtain continuous EEG or cerebral oximetry signals due to technical reasons (e.g., scalp injury, abnormal probe placement site).
  5. Patients expected to die within 24 hours.
  6. Patients deemed unsuitable for the study by the investigator.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Cardiac Surgery Patients
Adult patients (18-80 years) admitted to the ICU after cardiac surgery (CABG, valve repair/replacement, major aortic surgery, or combined procedures) who meet all inclusion criteria and provide informed consent. All participants receive standard clinical care without any experimental interventions. They undergo multimodal monitoring (continuous frontal EEG, bilateral rScO₂, invasive arterial blood pressure) and serial delirium assessments (CAM-ICU) according to the study schedule.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of Postoperative Delirium (POD)
Time Frame: From ICU admission until ICU discharge or Day 7 postoperatively, whichever occurs first.
The proportion of participants who develop postoperative delirium during the ICU stay following cardiac surgery. Delirium is diagnosed using the Confusion Assessment Method for the ICU (CAM-ICU) and classified as positive (delirium present) or negative (no delirium).
From ICU admission until ICU discharge or Day 7 postoperatively, whichever occurs first.
Time to Onset of Postoperative Delirium
Time Frame: From end of surgery until first documented delirium or ICU discharge, up to 7 days.
The time (in hours) from the end of cardiac surgery (skin closure) to the first positive CAM-ICU assessment. Only for participants who develop POD.
From end of surgery until first documented delirium or ICU discharge, up to 7 days.
Duration of Postoperative Delirium
Time Frame: From first delirium onset until delirium resolution or ICU discharge, up to 7 days.
The total duration (in hours) from the first positive CAM-ICU assessment to the last positive CAM-ICU assessment, with no recurrence within 24 hours.
From first delirium onset until delirium resolution or ICU discharge, up to 7 days.

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Duration of Mechanical Ventilation
Time Frame: From ICU admission until extubation, assessed throughout ICU stay, up to 30 days.
Total time (in hours) from endotracheal intubation to successful extubation (or removal of ventilatory support) during the index ICU stay.
From ICU admission until extubation, assessed throughout ICU stay, up to 30 days.
Intensive Care Unit Length of Stay
Time Frame: From ICU admission to ICU discharge, up to 30 days.
Total number of days spent in the ICU from the date of ICU admission to the date of ICU discharge.
From ICU admission to ICU discharge, up to 30 days.
Hospital Length of Stay
Time Frame: From hospital admission to hospital discharge, up to 90 days.
Total number of days from hospital admission (for cardiac surgery) to hospital discharge.
From hospital admission to hospital discharge, up to 90 days.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Southeast University, China

Investigators

  • Study Chair: Jingyuan Xu, MD, Southeast University School of Medicine

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

July 6, 2026

Primary Completion (Estimated)

December 1, 2027

Study Completion (Estimated)

December 30, 2027

Study Registration Dates

First Submitted

June 30, 2026

First Submitted That Met QC Criteria

June 30, 2026

First Posted (Actual)

July 7, 2026

Study Record Updates

Last Update Posted (Actual)

July 8, 2026

Last Update Submitted That Met QC Criteria

July 6, 2026

Last Verified

July 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 2026ZDSYLL134-P01
  • 82572527 (Other Grant/Funding Number: The National Natural Science Foundations of China)
  • 82272211 (Other Grant/Funding Number: The National Natural Science Foundations of China)
  • BK20252100 (Other Grant/Funding Number: The General Natural Science Foundation of Jiangsu Province)
  • zdyyxy29 (Other Grant/Funding Number: Jiangsu Province High-Level Hospital Pairing Assistance)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

This is an exploratory single-center observational study. A formal individual participant data (IPD) sharing plan has not been established. De-identified data may be made available upon reasonable request to the corresponding author after publication, subject to institutional review board approval and a data use agreement.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Subscribe