Cerebral Autoregulation and Delirium Study (AUTO-POD)

Reducing Delirium After Cardiac Surgery: Personalized Targeted Blood Pressure Management Strategy Using Cerebral Autoregulation Monitoring: A Pilot Study

Approximately one in four elderly patients develops postoperative delirium (POD) after cardiac surgery. POD is associated with prolonged hospitalization, increased mortality, and higher health care costs. While patient-related risk factors are often difficult to modify, surgery- and anesthesia-related factors may be optimized to reduce the incidence of POD. One potentially modifiable factor is intraoperative blood pressure management. Current practice commonly relies on standardized blood pressure targets during cardiac surgery; however, this "one-size-fits-all" approach may not account for individual variability in cerebral perfusion requirements. This study proposes a personalized blood pressure management strategy based on real-time monitoring of cerebral autoregulation, with the goal of maintaining optimal cerebral perfusion and protecting the brain from both hypo- and hyper-perfusion

Study Overview

• Status: Not yet recruiting
• Conditions: Cardiac Surgery; Delirium - Postoperative
• Intervention / Treatment: Device: Mespere NeuroOs (Mespere Life Sciences) monitor

Detailed Description

The primary aim of this pilot study is to evaluate the feasibility of conducting a subsequent definitive trial by assessing recruitment rates, protocol adherence, and the completeness and quality of short-term outcome data collection. The pilot study will also provide an opportunity to identify potential challenges and optimize the design of the larger trial, if necessary.

If the study hypothesis is confirmed and subsequently reproduced in larger, rigorous clinical trials, the findings could have important implications for intraoperative blood pressure management in elderly patients undergoing cardiac surgery. Specifically, this research may support a transition from the current "one-size-fits-all" blood pressure management strategy toward an individualized, real-time approach guided by cerebral autoregulation monitoring. Such a personalized strategy could potentially reduce the incidence of postoperative delirium (POD) in this high-risk population.

Conversely, premature implementation of personalized blood pressure management based solely on the currently available preliminary evidence may lead to unintended adverse consequences. Therefore, the proposed pilot study is essential to provide critical feasibility and safety data before proceeding to a larger definitive trial.

This study will be conducted as a prospective, single-centre, randomized controlled clinical trial comparing a real-time cerebral autoregulation monitoring-based blood pressure management strategy with standard care. Participants will be randomized into two groups:

Intervention Group: Blood pressure management guided by real-time cerebral autoregulation monitoring.

Control Group: Standard intraoperative blood pressure management according to current institutional practice.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Deep Grewal; Phone Number: 4221 416-340-4800; Email: deep.grewal@uhn.ca
• Study Contact Backup: Name: George Djaiani, MD FRCAFRCPS; Phone Number: 6205 416-340-4800; Email: george.djaiani@uhn.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Consenting patients aged ≥ 60 years undergoing elective complex cardiac surgery (coronary artery bypass grafting plus valve surgery, double-valve surgery, triple-valve surgery, redo operations, or aortic arch surgery), or patients aged ≥ 70 years undergoing isolated coronary artery bypass grafting or single-valve repair/replacement surgery.

Exclusion Criteria:

• Patients with symptomatic cerebrovascular disease.
• History of delirium.
• Major neurocognitive impairment (e.g., dementia or Mini-Mental State Examination score < 10).
• Schizophrenia.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention Group: Participants randomized to the intervention group will receive individualized intraoperative blood pressure management guided by real-time cerebral autoregulation monitoring to protect against both hypo- and hyper-cerebral perfusion. Cerebral autoregulation will be assessed using the cerebral blood volume reactivity index (VRx), defined as the Pearson correlation coefficient between blood volume index (BVI) and mean arterial pressure (MAP). The lower and upper limits of autoregulation will be identified as the MAP values at which VRx exceeds 0.3. If VRx remains outside the autoregulatory range for more than 60 seconds, the anesthesiologist may intervene to restore MAP within the individualized autoregulatory zone. The type and sequence of interventions will be at the discretion of the attending anesthesiologist.	Device: Mespere NeuroOs (Mespere Life Sciences) monitor; bilateral Mespere NeuroOs cerebral oximeter sensors will be placed on the fronto-temporal area on the fronto-temporal area of all patients.
Active Comparator: Control Group: In the control group, the cerebral oximetry monitor will be electronically blinded, although data will be continuously recorded for subsequent analysis. Intraoperative blood pressure management will follow current institutional standard practice at the discretion of the attending anesthesiologist.	Device: Mespere NeuroOs (Mespere Life Sciences) monitor; bilateral Mespere NeuroOs cerebral oximeter sensors will be placed on the fronto-temporal area on the fronto-temporal area of all patients.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Recruitment rate	1. Recruitment rate: Percentage of eligible patients enrolled in the study (feasibility target: >10%).	2 year
Non-adherence with the protocol	Non-adherence with the protocol (percentage of patients with VRx > 0.3 where no intervention was performed; <10%)	2 year
Completeness and quality of POD assessment	Completeness and quality of POD assessment (percent of patients for whom all CAM-ICU assessments are complete and conclusive; > 90%)	2 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall incidence of impaired cerebral autoregulation	Overall incidence of impaired cerebral autoregulation in the intervention and control groups.	2 year
Percentage of patients in whom attempted restoration	Percentage of patients in whom attempted restoration of VRx to autoregulation range was unsuccessful	2 year
The number of interventions required	The number of interventions required to restore VRx to autoregulation range	2 year

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Tertiary Outcomes: . Frequency of POD	Frequency of postoperative delirium (POD) up to postoperative day 3 in both study groups (primary outcome for the definitive trial).	2 year
Tertiary Outcomes: A composite outcome of major end organ dysfunction	A composite outcome of major end organ dysfunction defined as major organ morbidity and mortality (MOMM) and all cause 30-day mortality.	2 year
Tertiary Outcomes: Postoperative quality of recovery	Postoperative quality of recovery score QoR-15 survey will be performed at baseline, and postoperative days 1 to 3 (or discharge if earlier).	2 year

Collaborators and Investigators

• Sponsor: University Health Network, Toronto
• Investigators: Principal Investigator: George Djaiani, Toronto General Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): June 30, 2028
• Study Completion (Estimated): June 30, 2028

Study Registration Dates

• First Submitted: May 21, 2026
• First Submitted That Met QC Criteria: June 22, 2026
• First Posted (Actual): June 26, 2026

Study Record Updates

• Last Update Posted (Actual): June 26, 2026
• Last Update Submitted That Met QC Criteria: June 22, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Cerebral Autoregulation Monitoring
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Mental Disorders; Postoperative Complications; Pathologic Processes; Confusion; Neurobehavioral Manifestations; Neurocognitive Disorders; Delirium; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Emergence Delirium; Diagnostic Techniques and Procedures; Diagnosis; Monitoring, Physiologic
• Other Study ID Numbers: 25-5746

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: No plan yet

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No