Impact of Personalised Cardiac Anaesthesia and Cerebral Autoregulation on Neurological Outcomes in Patients Undergoing Cardiac Surgery

Impact of Personalised Cardiac Anaesthesia and Cerebral Autoregulation on Neurological Outcomes in Patients Undergoing Cardiac Surgery (PRECISION)

This international, multicentre prospective cohort study will assess whether perioperative duration and magnitude of mean arterial pressure (MAP) outside of an individual's cerebral autoregulation (CA) limits using near-infrared spectroscopy (NIRS) and transcranial Doppler (TCD) are associated with adverse neurological events. It is to investigate whether patients with a higher burden of cerebral haemodynamic insults have an increased incidence or poorer neurological outcomes. Associations between neurologic outcomes, neurobiomarkers and genetic tests will be explored.

Adverse neurological events include perioperative neurocognitive disorders and stroke and remain one of the major risks after cardiac surgery. A lack of a comprehensive knowledge of their causes and neuroprotective strategies has hindered the development of strategies to effectively reduce these complications. Against this background, this research project will take three approaches. First, non-invasive, personalised cerebral autoregulation-oriented blood pressure monitoring aims to reduce complications by uncovering blood pressure targets tailored to individual characteristics. In parallel, establishing biological associations between adverse neurological outcomes, brain injury biomarkers and genetic studies are complementary strategies that make a move to a proactive patient-tailored paradigm, ultimately understanding the mechanisms and improving patient outcomes, patient safety and quality of life.

Therefore, this international, multicentre prospective cohort study will assess whether perioperative duration and magnitude of MAP outside of an individual's CA limits using NIRS and TCD are associated with adverse neurological events. It is to investigate whether patients with a higher burden of cerebral haemodynamic insults, defined by the duration and magnitude spent outside of an individual's CA limits based on NIRS and/or TCD, have an increased incidence of postoperative delirium (POD), stroke or cognitive decline. Biological associations between adverse neurological outcomes, the role of brain injury serum biomarkers will be explored. Genetic studies will be conducted on participants who give written informed consent for these further investigations.

Inclusion Criteria:

• Elective primary or reoperative coronary artery bypass graft and/or valvular and/or ascending aorta surgery requiring cardiopulmonary bypass.

Exclusion Criteria:

• Surgery requiring moderate (28-31.9ºC) or deep (<28ºC) hypothermic circulatory arrest;
• Heart and/or lung transplantation;
• Urgent (within 24 hours) and emergency surgery;
• Inability to follow procedures or insufficient knowledge in English, German or French;
• Inability to give consent.

Participants who undergo cardiac surgery under minimal extracorporeal circulation will also be excluded.