18
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Cerebrovascular Autoregulation Monitoring in the Management of Adult Severe Traumatic Brain Injury: A Delphi Consensus of Clinicians

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Background

          Several methods have been proposed to measure cerebrovascular autoregulation (CA) in traumatic brain injury (TBI), but the lack of a gold standard and the absence of prospective clinical data on risks, impact on care and outcomes of implementation of CA-guided management lead to uncertainty.

          Aim

          To formulate statements using a Delphi consensus approach employing a group of expert clinicians, that reflect current knowledge of CA, aspects that can be implemented in TBI management and CA research priorities.

          Methods

          A group of 25 international academic experts with clinical expertise in the management of adult severe TBI patients participated in this consensus process. Seventy-seven statements and multiple-choice questions were submitted to the group in two online surveys, followed by a face-to-face meeting and a third online survey. Participants received feedback on average scores and the rationale for resubmission or rephrasing of statements. Consensus on a statement was defined as agreement of more than 75% of participants.

          Results

          Consensus amongst participants was achieved on the importance of CA status in adult severe TBI pathophysiology, the dynamic non-binary nature of CA impairment, its association with outcome and the inadvisability of employing universal and absolute cerebral perfusion pressure targets. Consensus could not be reached on the accuracy, reliability and validation of any current CA assessment method. There was also no consensus on how to implement CA information in clinical management protocols, reflecting insufficient clinical evidence.

          Conclusion

          The Delphi process resulted in 25 consensus statements addressing the pathophysiology of impaired CA, and its impact on cerebral perfusion pressure targets and outcome. A research agenda was proposed emphasizing the need for better validated CA assessment methods as well as the focused investigation of the application of CA-guided management in clinical care using prospective safety, feasibility and efficacy studies.

          Supplementary Information

          The online version contains supplementary material available at. 10.1007/s12028-020-01185-x.

          Related collections

          Most cited references44

          • Record: found
          • Abstract: found
          • Article: not found

          Integrative regulation of human brain blood flow.

          Herein, we review mechanisms regulating cerebral blood flow (CBF), with specific focus on humans. We revisit important concepts from the older literature and describe the interaction of various mechanisms of cerebrovascular control. We amalgamate this broad scope of information into a brief review, rather than detailing any one mechanism or area of research. The relationship between regulatory mechanisms is emphasized, but the following three broad categories of control are explicated: (1) the effect of blood gases and neuronal metabolism on CBF; (2) buffering of CBF with changes in blood pressure, termed cerebral autoregulation; and (3) the role of the autonomic nervous system in CBF regulation. With respect to these control mechanisms, we provide evidence against several canonized paradigms of CBF control. Specifically, we corroborate the following four key theses: (1) that cerebral autoregulation does not maintain constant perfusion through a mean arterial pressure range of 60-150 mmHg; (2) that there is important stimulatory synergism and regulatory interdependence of arterial blood gases and blood pressure on CBF regulation; (3) that cerebral autoregulation and cerebrovascular sensitivity to changes in arterial blood gases are not modulated solely at the pial arterioles; and (4) that neurogenic control of the cerebral vasculature is an important player in autoregulatory function and, crucially, acts to buffer surges in perfusion pressure. Finally, we summarize the state of our knowledge with respect to these areas, outline important gaps in the literature and suggest avenues for future research.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Continuous monitoring of cerebrovascular pressure reactivity allows determination of optimal cerebral perfusion pressure in patients with traumatic brain injury.

            To define optimal cerebral perfusion pressure (CPPOPT) in individual head-injured patients using continuous monitoring of cerebrovascular pressure reactivity. To test the hypothesis that patients with poor outcome were managed at a cerebral perfusion pressure (CPP) differing more from their CPPOPT than were patients with good outcome. Retrospective analysis of prospectively collected data. Neurosciences critical care unit of a university hospital. A total of 114 head-injured patients admitted between January 1997 and August 2000 with continuous monitoring of mean arterial blood pressure (MAP) and intracranial pressure (ICP). MAP, ICP, and CPP were continuously recorded and a pressure reactivity index (PRx) was calculated online. PRx is the moving correlation coefficient recorded over 4-min periods between averaged values (6-sec periods) of MAP and ICP representing cerebrovascular pressure reactivity. When cerebrovascular reactivity is intact, PRx has negative or zero values, otherwise PRx is positive. Outcome was assessed at 6 months using the Glasgow Outcome Scale. A total of 13,633 hrs of data were recorded. CPPOPT was defined as the CPP where PRx reaches its minimum value when plotted against CPP. Identification of CPPOPT was possible in 68 patients (60%). In 22 patients (27%), CPPOPT was not found because it presumably lay outside the studied range of CPP. Patients' outcome correlated with the difference between CPP and CPPOPT for patients who were managed on average below CPPOPT (r =.53, p <.001) and for patients whose mean CPP was above CPPOPT (r = -.40, p <.05). CPPOPT could be identified in a majority of patients. Patients with a mean CPP close to CPPOPT were more likely to have a favorable outcome than those whose mean CPP was more different from CPPOPT. We propose use of the criterion of minimal achievable PRx to guide future trials of CPP oriented treatment in head injured patients.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Cerebral autoregulation dynamics in humans.

              We studied the response of cerebral blood flow to acute step decreases in arterial blood pressure noninvasively and nonpharmacologically in 10 normal volunteers during normocapnia, hypocapnia, and hypercapnia. The step (approximately 20 mm Hg) was induced by rapidly deflating thigh blood pressure cuffs following a 2-minute inflation above systolic blood pressure. Instantaneous arterial blood pressure was measured by a new servo-cuff method, and cerebral blood flow changes were assessed by transcranial Doppler recording of middle cerebral artery blood flow velocity. In hypocapnia, full restoration of blood flow to the pretest level was seen as early as 4.1 seconds after the step decrease in blood pressure, while the response was slower in normocapnia and hypercapnia. The time course of cerebrovascular resistance was calculated from blood pressure and blood flow recordings, and rate of regulation was determined as the normalized change in cerebrovascular resistance per second during 2.5 seconds just after the step decrease in blood pressure. The reference for normalization was the calculated change in cerebrovascular resistance that would have nullified the effects of the step decrease in arterial blood pressure on cerebral blood flow. The rate of regulation was 0.38, 0.20, and 0.11/sec in hypocapnia, normocapnia, and hypercapnia, respectively. There was a highly significant inverse relation between rate of regulation and PaCO2 (p less than 0.001), indicating that the response rate of cerebral autoregulation in awake normal humans is profoundly dependent on vascular tone.
                Bookmark

                Author and article information

                Contributors
                bart.depreitere@uzleuven.be
                Journal
                Neurocrit Care
                Neurocrit Care
                Neurocritical Care
                Springer US (New York )
                1541-6933
                1556-0961
                25 January 2021
                25 January 2021
                2021
                : 34
                : 3
                : 731-738
                Affiliations
                [1 ]GRID grid.410569.f, ISNI 0000 0004 0626 3338, Neurosurgery, , University Hospitals Leuven, ; Herestraat 49, B-3000 Leuven, Belgium
                [2 ]GRID grid.7563.7, ISNI 0000 0001 2174 1754, Intensive Care Medicine, School of Medicine and Surgery, , University of Milan-Bicocca, ; Milan, Italy
                [3 ]GRID grid.83440.3b, ISNI 0000000121901201, Neurocritical Care Unit, National Hospital for Neurology and Neurosurgery, , University College London, ; London, UK
                [4 ]GRID grid.134563.6, ISNI 0000 0001 2168 186X, Barrow Neurological Institute At Phoenix Childrens Hospital, Department of Child Health/Neurosurgery, , University of Arizona College of Medicine, ; Tucson, AZ USA
                [5 ]GRID grid.215654.1, ISNI 0000 0001 2151 2636, Department of Neurosurgery, Mayo Clinic School of Medicine, School of Biological and Health Systems Engineering, , Arizona State University, ; Tempe, AZ USA
                [6 ]GRID grid.5012.6, ISNI 0000 0001 0481 6099, Department of Intensive Care, Maastricht University Medical Center, , University of Maastricht, ; Maastricht, The Netherlands
                [7 ]GRID grid.16753.36, ISNI 0000 0001 2299 3507, Davee Department of Neurology, , Northwestern University Feinberg School of Medicine, ; Chicago, IL USA
                [8 ]GRID grid.410529.b, ISNI 0000 0001 0792 4829, Grenoble Alps Trauma Center, Department of Anesthesiology and Intensive Care Medicine, , Grenoble University Hospital, ; Grenoble, France
                [9 ]GRID grid.34477.33, ISNI 0000000122986657, Department of Neurological Surgery, Harborview Medical Center, , University of Washington, ; Seattle, WA USA
                [10 ]GRID grid.410569.f, ISNI 0000 0004 0626 3338, Anesthesiology, , University Hospitals Leuven, ; Leuven, Belgium
                [11 ]GRID grid.4367.6, ISNI 0000 0001 2355 7002, Department of Neurology, Barnes-Jewish Hospital, , Washington University School of Medicine, ; St. Louis, MO USA
                [12 ]GRID grid.5842.b, ISNI 0000 0001 2171 2558, Université Paris Sud - Hôpitaux Universitaires Paris-Sud, ; Paris, France
                [13 ]GRID grid.120073.7, ISNI 0000 0004 0622 5016, Division of Anaesthesia, Department of Medicine, , Addenbrooke’s Hospital, University of Cambridge, ; Cambridge, UK
                [14 ]GRID grid.21613.37, ISNI 0000 0004 1936 9609, Section of Neurosurgery, , University of Manitoba, ; Winnipeg, MB Canada
                [15 ]GRID grid.413301.4, ISNI 0000 0001 0523 9342, Head and Neck Anaesthesia and Neurocritical Care, , Institute of Neurological Sciences, ; Glasgow, UK
                [16 ]GRID grid.5361.1, ISNI 0000 0000 8853 2677, Department of Neurology, , Medical University of Innsbruck, ; Innsbruck, Austria
                [17 ]GRID grid.411326.3, ISNI 0000 0004 0626 3362, Neurosurgery, University Hospital Brussels, ; Brussels, Belgium
                [18 ]GRID grid.7700.0, ISNI 0000 0001 2190 4373, Department of Neurosurgery, , University of Heidelberg, ; Heidelberg, Germany
                [19 ]Policlinico San Martino, IRCCS for Oncology and Neuroscience, Genova, Italy
                [20 ]GRID grid.410567.1, Anesthesiology, , University Hospital Basel, ; Basel, Switzerland
                [21 ]GRID grid.6612.3, ISNI 0000 0004 1937 0642, Department of Clinical Research, , University of Basel, ; Basel, Switzerland
                [22 ]GRID grid.414818.0, ISNI 0000 0004 1757 8749, Department of Physiopathology and Transplant, , Milan University and Neuro ICU Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, ; Milan, Italy
                [23 ]GRID grid.4989.c, ISNI 0000 0001 2348 0746, Department of Intensive Care, , Hôpital Erasme, Université Libre de Bruxelles (ULB), ; Brussels, Belgium
                [24 ]GRID grid.224260.0, ISNI 0000 0004 0458 8737, Department of Neurosurgery, , Virginia Commonwealth University, ; Richmond, VA USA
                [25 ]GRID grid.6363.0, ISNI 0000 0001 2218 4662, Department of Neurosurgery, , University Hospital Berlin Charité, ; Berlin, Germany
                [26 ]GRID grid.21613.37, ISNI 0000 0004 1936 9609, Section of Neurosurgery, Department of Surgery, Rady Faculty of Health Sciences, , University of Manitoba, ; Winnipeg, Canada
                [27 ]GRID grid.21613.37, ISNI 0000 0004 1936 9609, Department of Anatomy and Cell Science, Rady Faculty of Health Sciences, , University of Manitoba, ; Winnipeg, Canada
                [28 ]GRID grid.21613.37, ISNI 0000 0004 1936 9609, Biomedical Engineering, Faculty of Engineering, , University of Manitoba, ; Winnipeg, Canada
                [29 ]GRID grid.21613.37, ISNI 0000 0004 1936 9609, Centre on Aging, , University of Manitoba, ; Winnipeg, Canada
                [30 ]GRID grid.410569.f, ISNI 0000 0004 0626 3338, Intensive Care Medicine, , University Hospitals Leuven, ; Leuven, Belgium
                Author information
                http://orcid.org/0000-0002-7458-0648
                Article
                1185
                10.1007/s12028-020-01185-x
                8179892
                33495910
                db187625-cc57-4c57-b256-493c3b9950c4
                © The Author(s) 2021

                Open AccessThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

                History
                : 22 September 2020
                : 31 December 2020
                Categories
                Original Work
                Custom metadata
                © Springer Science+Business Media, LLC, part of Springer Nature and Neurocritical Care Society 2021

                Emergency medicine & Trauma
                traumatic brain injury,adult,cerebral perfusion pressure,cerebral blood flow,homeostasis,consensus development

                Comments

                Comment on this article