The Impact of Blood Pressure Below Personalized Lower Cerebral Autoregulation Limit on Outcomes After Cardiac...

Area of Science:

• Cardiovascular Surgery
• Neuroanesthesia
• Critical Care Medicine

Background:

• Individualized blood pressure management is crucial for cerebral perfusion during cardiac surgery.
• Optimal blood pressure targets for cerebral autoregulation remain debated.
• Cerebral autoregulation monitoring aims to personalize hemodynamic management.

Purpose of the Study:

• To investigate the association between cerebral autoregulation metrics and postoperative outcomes.
• To determine if time spent with mean arterial pressure (MAP) below the lower limit of autoregulation (LLA) predicts major morbidity and mortality (MMOM).

Main Methods:

• Retrospective observational study of 686 cardiovascular surgeries.
• Analysis of the area under the curve for MAP below LLA (AUC_ABP).
• Association analysis with stroke, acute kidney injury, low cardiac output syndrome, prolonged ventilation, and operative mortality.

Main Results:

• No significant association was found between AUC_{ABP and overall MMOM.}
• Significant associations were observed between AUC_{ABP and operative mortality (p < 0.05).}
• Significant associations were also found between AUC_{ABP and low cardiac output syndrome (p < 0.05), after adjusting for covariates.}

Conclusions:

• Metrics related to the lower limit of autoregulation have limited predictive value for major morbidity and mortality in cardiac surgery.
• Further research is needed to clarify the role and applicability of LLA-related metrics in diverse patient populations and clinical settings.