Continuous cerebrovascular reactivity monitoring in moderate/severe traumatic brain injury: a narrative review of advances in neurocritical care

Abstract

Impaired cerebrovascular reactivity in adult moderate and severe traumatic brain injury (TBI) is known to be associated with worse global outcome at 6e12 months. As technology has improved over the past decades, monitoring of cerebrovascular reactivity has shifted from intermittent measures, to experimentally validated continuously updating indices at the bedside. Such advances have led to the exploration of individualised physiologic targets in adult TBI management, such as optimal cerebral perfusion pressure (CPP) values, or CPP limits in which vascular reactivity is relatively intact. These targets have been shown to have a stronger association with outcome compared with existing consensus-based guideline thresholds in severe TBI care. This has sparked ongoing prospective trials of such personalised medicine approaches in adult TBI. In this narrative review paper, we focus on the concept of cerebral autoregulation, proposed mechanisms of control and methods of continuous monitoring used in TBI. We highlight multimodal cranial monitoring approaches for continuous cerebrovascular reactivity assessment, physiologic and neuroimaging correlates, and associations with outcome. Finally, we explore the recent 'state-of-the-art' advances in personalised physiologic targets based on continuous cerebrovascular reactivity monitoring, their benefits, and implications for future avenues of research in TBI.

Diffuse Intracranial Injury Patterns Are Associated with Impaired Cerebrovascular Reactivity in Adult Traumatic Brain Injury: A CENTER-TBI Validation Study

“…Such work will involve the integration of proteomics and genomic information which cerebrovascular physiology, in order to uncover the molecular pathways and therapeutic targets to prevent and treat impaired cerebrovascular reactivity. 35,36 Limitations:…”

Year in Review: Synopsis of Selected Articles in Neuroanesthesia and Neurocritical Care from 2020

“…Zeiler et al have done a narrative review focusing on the concept of cerebral autoregulation, proposed mechanisms of control and methods of continuous cerebrovascular reactivity monitoring used in moderate/severe traumatic brain injury. 26 Minhas et al have presented a multidisciplinary narrative review describing the key pathophysiological and clinical considerations on the perioperative care for patients with a prior diagnosis of stroke. 27 On the similar topic, Society for Neuroscience in Anesthesiology and Critical Care has recently updated the initial consensus statement from 2014 and have provided evidence-based recommendations regarding perioperative care of patients at high risk for stroke.…”

Protective Effects of Aquaporin-4 Deficiency on Longer-Term Neurological Outcomes in a Mouse Model of Traumatic Brain Injury

“…Traumatic brain injury (TBI) is de ned as traumatic structural damage and/or brain dysfunction caused by external forces, which may induce the loss or reduction of consciousness and memory, mental disorders, neurological dysfunction, and intracranial damage [1,2]. Although with the rapid development of emergency medicine and critical care technology, the success rate of TBI emergency treatment has increased signi cantly, and the overall mortality rate of TBI has dropped from 50-30% [3].…”