NCT05336864

Association of Intraoperative Blood Pressure Excursions Below Cerebral Autoregulatory Boundaries With Organ Injury Following Major Noncardiac Surgery

Association of Intraoperative Blood Pressure Excursions Below Cerebral Autoregulatory Boundaries With Organ Injury Following Major Noncardiac Surgery (AUTOREGULATE-NONCARDIAC)

• Status: Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 650 (estimated)
• Sponsor: University Hospital, Basel, Switzerland · Academic / Other
• Sex: All
• Age: 45 Years
• Healthy volunteers: Not accepted

Summary

The aim of study is to investigate the clinical relevance of blood pressure (BP) excursions below cerebral autoregulatory boundaries in major noncardiac surgery. The study seeks to establish a precedent for a personalized definition of intraoperative arterial hypotension based on non-invasive tissue oxygenation measurements. The feasibility of NIRS-based autoregulation monitoring in major noncardiac surgery and the prognostic relevance of BP excursions below the NIRS-derived lower limit of autoregulation (LLA) with regard to major cardiovascular, renal and neurological complications will be investigated.

Detailed description

Major adverse cardiovascular events (MACE) are leading causes of perioperative morbidity and mortality following major noncardiac surgery. Intraoperative arterial hypotension is strongly associated with postoperative morbidity and mortality. However, interventional trials have been unable to demonstrate clinically relevant reductions in the incidence of postoperative MACE, which can potentially be explained by the hitherto lacking consideration of patient-specific autoregulatory boundaries. This is especially problematic considering that the presumed mechanism of hypotension-induced organ injury is hypoperfusion due to transgression of the lower limit of blood flow autoregulation. In other clinical settings, excursions below the autoregulatory threshold have been shown to be superior predictors of adverse events than excursions below absolute blood pressure (BP) thresholds, however, there is a paucity of data in major noncardiac surgery. This prospective, multicenter cohort observation study aims to investigate the clinical relevance of blood pressure excursions below autoregulatory boundaries and to determine the association of other measures of disturbed intraoperative cerebral autoregulatory function in major noncardiac surgery. This project will consist of a Main study in which all patients will be enrolled and of substudies on perioperative neurologic injury, tissue perfusion, postoperative hemodynamics, and processed electroencephalogram (EEG), in which selected patients will be enrolled.

Conditions

• Intraoperative Arterial Hypotension

Interventions

Type	Name	Description
OTHER	Non-invasive cerebral oximetry monitoring	Main study (all patients): Continuous bilateral frontal cerebral near-infrared spectroscopy (NIRS) monitoring will be performed in all patients for the duration of general anesthesia. Intraoperative parameters including NIRS and invasive blood pressure will be collected and recorded in real-time using the software ICM+. Postoperative hemodynamics substudy (facultative): Cerebral NIRS monitoring will be continued postoperatively in a subset of patients being admitted to the ICU.
OTHER	additional perioperative blood sampling	Main study (all patients): Creatinine, high-sensitivity troponin (T hs-cTnT), Growth/Differentiation Factor-15 (GDF-15), Hemoglobin Neurological injury substudy (facultative): Neurofilament Light Chain (NFL) and C-reactive protein (CRP)
OTHER	clinical & telephone assessments	Main study (all patients): Telephone follow-up (1-year outcomes).
OTHER	Non-invasive somatic oximetry monitoring	Tissue perfusion substudy (facultative): Continuous somatic NIRS monitoring of an extremity (i.e. on skin of leg or arm) will be performed intraoperatively and postoperatively in a subset of patients being admitted postoperatively to the ICU.
OTHER	Processed electroencephalogram (pEEG) monitoring	Processed EEG substudy to explore the relationship between processed EEG-derived depth of anesthesia metrics and cerebral autoregulatory function.

Timeline

• Start date: 2022-05-20
• Primary completion: 2026-01-01
• Completion: 2027-01-01
• First posted: 2022-04-20
• Last updated: 2025-07-17

Locations

3 sites across 1 country: Switzerland