Autoregulation in the Neuro ICU
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Purpose of review
The purpose of this review is to briefly describe the concept of cerebral autoregulation, to detail several bedside techniques for measuring and assessing autoregulation, and to outline the impact of impaired autoregulation on clinical and functional outcomes in acute brain injury. Furthermore, we will review several autoregulation studies in select forms of acute brain injuries, discuss the potential for its use in patient management in the ICU, and suggest further avenues for research.
Cerebral autoregulation plays a critical role in regulating cerebral blood flow, and impaired autoregulation has been associated with worse functional and clinical outcomes in various acute brain injuries. There exists a multitude of methods to assess the autoregulatory state in patients using both invasive and non-invasive modalities. Continuous monitoring of patients in the ICU has yielded autoregulatory-derived optimal perfusion pressures that may prevent secondary injury and improve outcomes.
Measuring autoregulation continuously at the bedside is now a feasible option for clinicians working in the ICU, although there exists a great need to standardize autoregulatory measurement. While the clinical benefits await prospective and randomized trials, autoregulation-derived parameters show enormous potential for creating an optimal physiological environment for the injured brain.
KeywordsCerebral autoregulation Bedside monitoring Critical care Traumatic brain injury, subarachnoid hemorrhage Ischemic stroke
Compliance with Ethical Standards
Conflict of Interest
Anson Wang, Santiago Ortega-Gutierrez, and Nils H. Petersen each declare no potential conflicts of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
References and Recommended Reading
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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