Neurological complications after cardiac surgery: anesthetic considerations based on outcome evidence

Yong Liu, Kun Chen, Wei Mei, Yong Liu, Kun Chen, Wei Mei

Abstract

Purpose of review: Neurological complications after cardiac surgery remain prevalent. This review aims to discuss the modifiable and outcome-relevant risk factors based on an up-to-date literature review, with a focus on interventions that may improve outcomes.

Recent findings: There is a close relationship between intraoperative blood pressure and postoperative neurological outcomes in cardiac surgical patients based on cohort studies and randomized controlled trials. Adopting an optimal and personalized blood pressure target is essential; however, the outstanding issue is the determination of this target. Maintaining cerebral tissue oxygen saturation at least 90% patient's baseline during cardiac surgery may be beneficial; however, the outstanding issues are effective intervention protocols and quality outcome evidence. Maintaining hemoglobin at least 7.5 g/dl may be adequate for cardiac surgical patients; however, this evidence is based on the pooled results of thousands of patients. We still need to know the optimal hemoglobin level for an individual patient, which is of particular relevance during the decision-making of transfusion or not.

Summary: The available evidence highlights the importance of maintaining optimal and individualized blood pressure, cerebral tissue oxygen saturation and hemoglobin level in improving neurological outcomes after cardiac surgery. However, outstanding issues remain and need to be addressed via outcome-oriented further research.

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