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Kartal A, Robba C, Helmy A, Wolf S, Aries MJH. How to Define and Meet Blood Pressure Targets After Traumatic Brain Injury: A Narrative Review. Neurocrit Care 2024; 41:369-385. [PMID: 38982005 PMCID: PMC11377672 DOI: 10.1007/s12028-024-02048-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 06/13/2024] [Indexed: 07/11/2024]
Abstract
BACKGROUND Traumatic brain injury (TBI) poses a significant challenge to healthcare providers, necessitating meticulous management of hemodynamic parameters to optimize patient outcomes. This article delves into the critical task of defining and meeting continuous arterial blood pressure (ABP) and cerebral perfusion pressure (CPP) targets in the context of severe TBI in neurocritical care settings. METHODS We narratively reviewed existing literature, clinical guidelines, and emerging technologies to propose a comprehensive approach that integrates real-time monitoring, individualized cerebral perfusion target setting, and dynamic interventions. RESULTS Our findings emphasize the need for personalized hemodynamic management, considering the heterogeneity of patients with TBI and the evolving nature of their condition. We describe the latest advancements in monitoring technologies, such as autoregulation-guided ABP/CPP treatment, which enable a more nuanced understanding of cerebral perfusion dynamics. By incorporating these tools into a proactive monitoring strategy, clinicians can tailor interventions to optimize ABP/CPP and mitigate secondary brain injury. DISCUSSION Challenges in this field include the lack of standardized protocols for interpreting multimodal neuromonitoring data, potential variability in clinical decision-making, understanding the role of cardiac output, and the need for specialized expertise and customized software to have individualized ABP/CPP targets regularly available. The patient outcome benefit of monitoring-guided ABP/CPP target definitions still needs to be proven in patients with TBI. CONCLUSIONS We recommend that the TBI community take proactive steps to translate the potential benefits of personalized ABP/CPP targets, which have been implemented in certain centers, into a standardized and clinically validated reality through randomized controlled trials.
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Affiliation(s)
- Ahmet Kartal
- University Hospital Heidelberg, Heidelberg University, Heidelberg, Germany.
| | - Chiara Robba
- Anesthesia and Intensive Care, IRCCS Policlinico San Martino, Genoa, Italy
- Department of Surgical Sciences and Integrated Sciences, University of Genoa, Genoa, Italy
| | - Adel Helmy
- Division of Neurosurgery, Department of Clinical Neurosciences, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
| | - Stefan Wolf
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Marcel J H Aries
- Department of Intensive Care Medicine, Maastricht University Medical Center, Maastricht University, Maastricht, The Netherlands
- Institute of Mental Health and Neurosciences, University Maastricht, Maastricht, The Netherlands
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Duque C, Mahinrad S, Sedaghat S, Higgins J, Milstead A, Sargento-Freitas J, Balabanov R, Cohen B, Sorond FA. Cerebrovascular hemodynamics association with brain structure and function in Multiple Sclerosis. Mult Scler Relat Disord 2024; 91:105882. [PMID: 39276598 DOI: 10.1016/j.msard.2024.105882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 09/02/2024] [Accepted: 09/06/2024] [Indexed: 09/17/2024]
Abstract
BACKGROUND Vascular risk factors seem to contribute to disease progression in Multiple Sclerosis (MS), but the mechanistic connection between vascular risk and MS is unknown. Understanding cerebrovascular hemodynamics (CVH) in MS may help advance our understanding of the link between vascular risk and MS. OBJECTIVES Examine the relationship between CVH [dynamic cerebral autoregulation (dCA) and vasoreactivity (VR)] and brain structure (MRI) and function (cognition, and gait) in individuals with MS. METHODS Transcranial Doppler ultrasound (TCD) was utilized to assess two key markers of CVH: dCA and VR. dCA (reported as phase and gain) is calculated from the spontaneous blood pressure and flow velocity oscillations. VR is calculated as the slope of change in cerebral blood flow velocity in response to end-tidal CO2. Global gray matter (GM), white matter (WM), WM hyperintensity (WMH) volumes and WM lesion counts were measured from brain MRI. All participants underwent detailed cognitive and gait assessments. RESULTS Eighty participants were included (age 44 ± 11, 26 % male); 75 had relapsing-remitting MS (94 %), with disease duration of 8 (11) years [median (IQR)] since MS diagnosis and an Expanded Disability Status Scale (EDSS) of 2.0 (4.0). Higher phase (better dCA) was associated with greater GM volume, lower WHM burden and higher cognitive scores in the memory and global cognitive domains (all P values <0.05). There was no relationship between CVH and gait speed in our study participants. There was no relationship between VR and any measures of brain structure and function. CONCLUSIONS More efficient cerebral autoregulation is associated with better brain structure (larger GM and lower WMH volumes) and function (cognition, but not gait) in patients with MS.
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Affiliation(s)
- Cristina Duque
- Department of Neurology, Hospital Pedro Hispano, Matosinhos, Portugal; Faculty of Medicine, Coimbra University, Coimbra, Portugal; Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, USA.
| | - Simin Mahinrad
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, USA
| | - Sanaz Sedaghat
- Division of Epidemiology and Community Health, University of Minnesota, MN, USA
| | - James Higgins
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, USA
| | - Andrew Milstead
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, USA
| | - João Sargento-Freitas
- Faculty of Medicine, Coimbra University, Coimbra, Portugal; Department of Neurology, Coimbra University Hospital, Coimbra, Portugal
| | - Roumen Balabanov
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, USA
| | - Bruce Cohen
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, USA
| | - Farzaneh A Sorond
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, USA
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Carlson AP, Mayer AR, Cole C, van der Horn HJ, Marquez J, Stevenson TC, Shuttleworth CW. Cerebral autoregulation, spreading depolarization, and implications for targeted therapy in brain injury and ischemia. Rev Neurosci 2024; 35:651-678. [PMID: 38581271 PMCID: PMC11297425 DOI: 10.1515/revneuro-2024-0028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 03/25/2024] [Indexed: 04/08/2024]
Abstract
Cerebral autoregulation is an intrinsic myogenic response of cerebral vasculature that allows for preservation of stable cerebral blood flow levels in response to changing systemic blood pressure. It is effective across a broad range of blood pressure levels through precapillary vasoconstriction and dilation. Autoregulation is difficult to directly measure and methods to indirectly ascertain cerebral autoregulation status inherently require certain assumptions. Patients with impaired cerebral autoregulation may be at risk of brain ischemia. One of the central mechanisms of ischemia in patients with metabolically compromised states is likely the triggering of spreading depolarization (SD) events and ultimately, terminal (or anoxic) depolarization. Cerebral autoregulation and SD are therefore linked when considering the risk of ischemia. In this scoping review, we will discuss the range of methods to measure cerebral autoregulation, their theoretical strengths and weaknesses, and the available clinical evidence to support their utility. We will then discuss the emerging link between impaired cerebral autoregulation and the occurrence of SD events. Such an approach offers the opportunity to better understand an individual patient's physiology and provide targeted treatments.
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Affiliation(s)
- Andrew P. Carlson
- Department of Neurosurgery, University of New Mexico School of Medicine, MSC10 5615, 1 UNM, Albuquerque, NM, 87131, USA
- Department of Neurosciences, University of New Mexico School of Medicine, 915 Camino de Salud NE, Albuquerque, NM, 87106, USA
| | - Andrew R. Mayer
- Mind Research Network, 1101 Yale, Blvd, NE, Albuquerque, NM, 87106, USA
| | - Chad Cole
- Department of Neurosurgery, University of New Mexico School of Medicine, MSC10 5615, 1 UNM, Albuquerque, NM, 87131, USA
| | | | - Joshua Marquez
- University of New Mexico School of Medicine, 915 Camino de Salud NE, Albuquerque, NM, 87106, USA
| | - Taylor C. Stevenson
- Department of Neurosurgery, University of New Mexico School of Medicine, MSC10 5615, 1 UNM, Albuquerque, NM, 87131, USA
| | - C. William Shuttleworth
- Department of Neurosciences, University of New Mexico School of Medicine, 915 Camino de Salud NE, Albuquerque, NM, 87106, USA
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Carlson AP, Jones T, Zhu Y, Desai M, Alsarah A, Shuttleworth CW. Oxygen-Based Autoregulation Indices Associated with Clinical Outcomes and Spreading Depolarization in Aneurysmal Subarachnoid Hemorrhage. Neurocrit Care 2024:10.1007/s12028-024-02088-x. [PMID: 39192101 DOI: 10.1007/s12028-024-02088-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Accepted: 07/29/2024] [Indexed: 08/29/2024]
Abstract
BACKGROUND Impairment in cerebral autoregulation has been proposed as a potentially targetable factor in patients with aneurysmal subarachnoid hemorrhage (aSAH); however, there are different continuous measures that can be used to calculate the state of autoregulation. In addition, it has previously been proposed that there may be an association of impaired autoregulation with the occurrence of spreading depolarization (SD) events. METHODS Study participants with invasive multimodal monitoring and aSAH were enrolled in an observational study. Autoregulation indices were prospectively calculated from this database as a 10 s moving correlation coefficient between various cerebral blood flow (CBF) surrogates and mean arterial pressure (MAP). In study participants with subdural electrocorticography (ECoG) monitoring, SD was also scored. Associations between clinical outcomes using the modified Rankin scale and occurrence of either isolated or clustered SD were assessed. RESULTS A total of 320 study participants were included, 47 of whom also had ECoG SD monitoring. As expected, baseline severity factors, such as modified Fisher scale score and World Federation of Neurosurgical Societies scale grade, were strongly associated with the clinical outcome. SD probability was related to blood pressure in a triphasic pattern, with a linear increase in probability below MAP of ~ 100 mm Hg. Multiple autoregulation indices were available for review based on moving correlations between mean arterial pressure (MAP) and various surrogates of cerebral blood flow (CBF). We calculated the pressure reactivity (PRx) using two different sources for intracranial pressure (ICP). We calculated the oxygen reactivity (ORx) using the partial pressure of brain tissue oxygen (PbtO2) from the Licox probe. We calculated the cerebral blood flow reactivity (CBFRx) using perfusion measurements from the Bowman perfusion probe. Finally, we calculated the cerebral oxygen saturation reactivity (OSRx) using regional cerebral oxygen saturation measured by near-infrared spectroscopy from the INVOS sensors. Only worse ORx and OSRx were associated with worse clinical outcomes. Both ORx and OSRx also were found to increase in the hour prior to SD for both sporadic and clustered SD. CONCLUSIONS Impairment in autoregulation in aSAH is associated with worse clinical outcomes and occurrence of SD when using ORx and OSRx. Impaired autoregulation precedes SD occurrence. Targeting the optimal MAP or cerebral perfusion pressure in patients with aSAH should use ORx and/or OSRx as the input function rather than intracranial pressure.
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Affiliation(s)
- Andrew P Carlson
- Department of Neurosurgery, University of Virginia School of Medicine, Charlottesville, VA, USA.
- Department of Neurosurgery, University of New Mexico School of Medicine, Albuquerque, NM, USA.
| | - Thomas Jones
- Department of Psychiatry, University of New Mexico School of Medicine, Albuquerque, NM, USA
| | - Yiliang Zhu
- Department of Internal Medicine, University of New Mexico School of Medicine, Albuquerque, NM, USA
| | - Masoom Desai
- Department of Neurology, University of New Mexico School of Medicine, Albuquerque, NM, USA
| | - Ali Alsarah
- Department of Neurology, Harvard University, Boston, MA, USA
| | - C William Shuttleworth
- Department of Neuroscience, University of New Mexico School of Medicine, Albuquerque, NM, USA
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Svedung Wettervik T, Hånell A, Howells T, Engström ER, Lewén A, Enblad P. Autoregulatory Cerebral Perfusion Pressure Insults in Traumatic Brain Injury and Aneurysmal Subarachnoid Hemorrhage: The Role of Insult Intensity and Duration on Clinical Outcome. J Neurosurg Anesthesiol 2024; 36:228-236. [PMID: 37212723 DOI: 10.1097/ana.0000000000000922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 04/10/2023] [Indexed: 05/23/2023]
Abstract
BACKGROUND This single-center, retrospective study investigated the outcome effect of the combined intensity and duration of differences between actual cerebral perfusion pressure (CPP) and optimal cerebral perfusion pressure (CPPopt), and also for absolute CPP, in patients with traumatic brain injury (TBI) and aneurysmal subarachnoid hemorrhage (aSAH). METHODS A total of 378 TBI and 432 aSAH patients treated in a neurointensive care unit between 2008 and 2018 with at least 24 hours of CPPopt data during the first 10 days following injury, and with 6-month (TBI) or 12-month (aSAH) extended Glasgow Outcome Scale (GOS-E) scores, were included in the study. ∆CPPopt-insults (∆CPPopt=actual CPP-CPPopt) and CPP-insults were visualized as 2-dimensional plots to highlight the combined effect of insult intensity (mm Hg) and duration (min) on patient outcome. RESULTS In TBI patients, a zone of ∆CPPopt ± 10 mm Hg was associated with more favorable outcome, with transitions towards unfavorable outcome above and below this zone. CPP in the range of 60 to 80 mm Hg was associated with higher GOS-E, whereas CPP outside this range was associated with lower GOS-E. In aSAH patients, there was no clear transition from higher to lower GOS-E for ∆CPPopt-insults; however, there was a transition from favorable to unfavorable outcome when CPP was <80 mm Hg. CONCLUSIONS TBI patients with CPP close to CPPopt exhibited better clinical outcomes, and absolute CPP within the 60 to 80 mm Hg range was also associated with favorable outcome. In aSAH patients, there was no clear transition for ∆CPPopt-insults in relation to outcome, whereas generally high absolute CPP values were associated overall with favorable recovery.
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Peng Q, Liu X, Ai M, Huang L, Li L, Liu W, Zhao C, Hu C, Zhang L. Cerebral autoregulation-directed optimal blood pressure management reduced the risk of delirium in patients with septic shock. JOURNAL OF INTENSIVE MEDICINE 2024; 4:376-383. [PMID: 39035614 PMCID: PMC11258506 DOI: 10.1016/j.jointm.2023.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 12/05/2023] [Accepted: 12/08/2023] [Indexed: 07/23/2024]
Abstract
Background When resuscitating patients with septic shock, cerebrovascular reactivity parameters are calculated by monitoring regional cerebral oxygen saturation (rSO2) using near-infrared spectroscopy to determine the optimal blood pressure. Here, we aimed to analyze the impact of cerebral autoregulation-directed optimal blood pressure management on the incidence of delirium and the prognosis of patients with septic shock. Methods This prospective randomized controlled clinical study was conducted in the Xiangya Hospital of Central South University, China. Fifty-one patients with septic shock (December 2020-May 2022) were enrolled and randomly allocated to the experimental (n=26) or control group (n=25). Using the ICM+ software, we monitored the dynamic changes in rSO2 and mean arterial pressure (MAP) and calculated the cerebrovascular reactivity parameter tissue oxygen reactivity index to determine the optimal blood pressure to maintain normal cerebral autoregulation function during resuscitation in the experimental group. The control group was treated according to the Surviving Sepsis Campaign Guidelines. Differences in the incidence of delirium and 28-day mortality between the two groups were compared, and the risk factors were analyzed. Results The 51 patients, including 39 male and 12 female, had a mean age of (57.0±14.9) years. The incidence of delirium was 40.1% (23/51), and the 28-day mortality rate was 29.4% (15/51). The mean MAP during the first 24 h of intensive care unit (ICU) admission was higher ([84.5±12.2] mmHg vs. [77.4±11.8] mmHg, P=0.040), and the incidence of delirium was lower (30.8% vs. 60.0%, P=0.036) in the experimental group than in the control group. The use of cerebral autoregulation-directed optimal blood pressure (odds ratio [OR]=0.090, 95% confidence interval [CI]: 0.009 to 0.923, P=0.043) and length of ICU stay (OR=1.473, 95% CI: 1.093 to 1.985, P=0.011) were risk factors for delirium during septic shock. Vasoactive drug dose (OR=8.445, 95% CI: 1.26 to 56.576, P=0.028) and partial pressure of oxygen (PaO2) (OR=0.958, 95% CI: 0.921 to 0.996, P=0.032) were the risk factors for 28-day mortality. Conclusions The use of cerebral autoregulation-directed optimal blood pressure management during shock resuscitation reduces the incidence of delirium in patients with septic shock. Trial Registration ClinicalTrials.gov ldentifer: NCT03879317.
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Affiliation(s)
- Qianyi Peng
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Xia Liu
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Meilin Ai
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Li Huang
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Li Li
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Wei Liu
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Chunguang Zhao
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Chenghuan Hu
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Lina Zhang
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
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Fedriga M, Martini S, Iodice FG, Sortica da Costa C, Pezzato S, Moscatelli A, Beqiri E, Czosnyka M, Smielewski P, Agrawal S. Cerebral autoregulation in paediatric and neonatal intensive care: A scoping review. J Cereb Blood Flow Metab 2024:271678X241261944. [PMID: 38867574 DOI: 10.1177/0271678x241261944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
Deranged cerebral autoregulation (CA) is associated with worse outcome in adult brain injury. Strategies for monitoring CA and maintaining the brain at its 'best CA status' have been implemented, however, this approach has not yet developed for the paediatric population. This scoping review aims to find up-to-date evidence on CA assessment in children and neonates with a view to identify patient categories in which CA has been measured so far, CA monitoring methods and its relationship with clinical outcome if any. A literature search was conducted for studies published within 31st December 2022 in 3 bibliographic databases. Out of 494 papers screened, this review includes 135 studies. Our literature search reveals evidence for CA measurement in the paediatric population across different diagnostic categories and age groups. The techniques adopted, indices and thresholds used to assess and define CA are heterogeneous. We discuss the relevance of available evidence for CA assessment in the paediatric population. However, due to small number of studies and heterogeneity of methods used, there is no conclusive evidence to support universal adoption of CA monitoring, technique, and methodology. This calls for further work to understand the clinical impact of CA monitoring in paediatric and neonatal intensive care.
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Affiliation(s)
- Marta Fedriga
- Neonatal and Paediatric Intensive Care Unit, IRCCS Giannina Gaslini Institute, Genoa, Italy
| | - Silvia Martini
- Neonatal Intensive Care Unit, IRCCS AOUBO, Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Francesca G Iodice
- Paediatric Cardiac Anaesthesia and Intensive Care Unit, IRCCS, Bambino Gesu' Hospital, Rome, Italy
| | | | - Stefano Pezzato
- Neonatal and Paediatric Intensive Care Unit, IRCCS Giannina Gaslini Institute, Genoa, Italy
| | - Andrea Moscatelli
- Neonatal and Paediatric Intensive Care Unit, IRCCS Giannina Gaslini Institute, Genoa, Italy
| | - Erta Beqiri
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, UK
| | - Marek Czosnyka
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, UK
| | - Peter Smielewski
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, UK
| | - Shruti Agrawal
- Department of Paediatric Intensive Care, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
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Klein SP, Decraene B, De Sloovere V, Kempen B, Meyfroidt G, Depreitere B. The Pressure Reactivity Index as a Measure for Cerebrovascular Autoregulation: Validation in a Porcine Cranial Window Model. Neurosurgery 2024:00006123-990000000-01207. [PMID: 38861643 DOI: 10.1227/neu.0000000000003019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Accepted: 04/09/2024] [Indexed: 06/13/2024] Open
Abstract
BACKGROUND AND OBJECTIVES Pressure reactivity index (PRx) has been proposed as a metric associated with cerebrovascular autoregulatory (CA) function and has been thoroughly investigated in clinical research. In this study, PRx is validated in a porcine cranial window model, developed to visualize pial arteriolar autoregulation and its limits. METHODS We measured arterial blood pressure, intracranial pressure, pial arteriolar diameter, and red blood cell (RBC) velocity in a closed cranial window piglet model during gradual balloon catheter-induced arterial hypotension (n = 10) or hypertension (n = 10). CA limits were derived through piecewise linear regression of calculated RBC flux vs cerebral perfusion pressure (CPP), leading for each arteriole to 1 lower limit of autoregulation (LLA) and 2 upper limits of autoregulation (ULA1 and ULA2). Autoregulation limits were compared with PRx thresholds, and receiver operating curve analysis was performed with and without CPP binning. A linear mixed effects model of PRx was performed. RESULTS Receiver operating curve analysis indicated an area under the curve (AUC) for LLA prediction by a PRx of 0.65 (95% CI: 0.64-0.67) and 0.77 (95% CI: 0.69-0.86) without and with CPP binning, respectively. The AUC for ULA1 prediction by PRx was 0.69 (95% CI: 0.68-0.69) without and 0.75 (95% CI: 0.68-0.82) with binning. The AUC for ULA2 prediction was 0.55 (95% CI: 0.55-0.58) without and 0.63 (95% CI 0.53-0.72) with binning. The sensitivity and specificity of binned PRx were 65%/90% for LLA, 69%/71% for ULA1, and 59%/74% for ULA2, showing wide interindividual variability. In the linear mixed effects model, pial arteriolar diameter changes were significantly associated with PRx changes (P = .002), whereas RBC velocity (P = .28) and RBC flux (P = .24) were not. CONCLUSION We conclude that PRx is predominantly determined by pial arteriolar diameter changes and moderately predicts CA limits. Performance to detect the CA limits varied highly on an individual level. Active therapeutic strategies based on PRx and the associated correlation metrics should incorporate these limitations.
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Affiliation(s)
- Samuel P Klein
- Neurosurgery Center Limburg, Jessa Hospital, Hasselt, Belgium
| | | | | | - Bavo Kempen
- Neurosurgery, University Hospitals Leuven, Leuven, Belgium
| | - Geert Meyfroidt
- Intensive Care Medicine, University Hospitals Leuven, Leuven, Belgium
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Vu EL, Brown CH, Brady KM, Hogue CW. Monitoring of cerebral blood flow autoregulation: physiologic basis, measurement, and clinical implications. Br J Anaesth 2024; 132:1260-1273. [PMID: 38471987 DOI: 10.1016/j.bja.2024.01.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 01/18/2024] [Accepted: 01/28/2024] [Indexed: 03/14/2024] Open
Abstract
Cerebral blood flow (CBF) autoregulation is the physiologic process whereby blood supply to the brain is kept constant over a range of cerebral perfusion pressures ensuring a constant supply of metabolic substrate. Clinical methods for monitoring CBF autoregulation were first developed for neurocritically ill patients and have been extended to surgical patients. These methods are based on measuring the relationship between cerebral perfusion pressure and surrogates of CBF or cerebral blood volume (CBV) at low frequencies (<0.05 Hz) of autoregulation using time or frequency domain analyses. Initially intracranial pressure monitoring or transcranial Doppler assessment of CBF velocity was utilised relative to changes in cerebral perfusion pressure or mean arterial pressure. A more clinically practical approach utilising filtered signals from near infrared spectroscopy monitors as an estimate of CBF has been validated. In contrast to the traditional teaching that 50 mm Hg is the autoregulation threshold, these investigations have found wide interindividual variability of the lower limit of autoregulation ranging from 40 to 90 mm Hg in adults and 20-55 mm Hg in children. Observational data have linked impaired CBF autoregulation metrics to adverse outcomes in patients with traumatic brain injury, ischaemic stroke, subarachnoid haemorrhage, intracerebral haemorrhage, and in surgical patients. CBF autoregulation monitoring has been described in both cardiac and noncardiac surgery. Data from a single-centre randomised study in adults found that targeting arterial pressure during cardiopulmonary bypass to above the lower limit of autoregulation led to a reduction of postoperative delirium and improved memory 1 month after surgery compared with usual care. Together, the growing body of evidence suggests that monitoring CBF autoregulation provides prognostic information on eventual patient outcomes and offers potential for therapeutic intervention. For surgical patients, personalised blood pressure management based on CBF autoregulation data holds promise as a strategy to improve patient neurocognitive outcomes.
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Affiliation(s)
- Eric L Vu
- Department of Anesthesiology, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA; The Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Charles H Brown
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kenneth M Brady
- The Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Department of Pediatrics, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
| | - Charles W Hogue
- The Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
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Chalifoux N, Ko T, Slovis J, Spelde A, Kilbaugh T, Mavroudis CD. Cerebral Autoregulation: A Target for Improving Neurological Outcomes in Extracorporeal Life Support. Neurocrit Care 2024:10.1007/s12028-024-02002-5. [PMID: 38811513 DOI: 10.1007/s12028-024-02002-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 04/18/2024] [Indexed: 05/31/2024]
Abstract
Despite improvements in survival after illnesses requiring extracorporeal life support, cerebral injury continues to hinder successful outcomes. Cerebral autoregulation (CA) is an innate protective mechanism that maintains constant cerebral blood flow in the face of varying systemic blood pressure. However, it is impaired in certain disease states and, potentially, following initiation of extracorporeal circulatory support. In this review, we first discuss patient-related factors pertaining to venovenous and venoarterial extracorporeal membrane oxygenation (ECMO) and their potential role in CA impairment. Next, we examine factors intrinsic to ECMO that may affect CA, such as cannulation, changes in pulsatility, the inflammatory and adaptive immune response, intracranial hemorrhage, and ischemic stroke, in addition to ECMO management factors, such as oxygenation, ventilation, flow rates, and blood pressure management. We highlight potential mechanisms that lead to disruption of CA in both pediatric and adult populations, the challenges of measuring CA in these patients, and potential associations with neurological outcome. Altogether, we discuss individualized CA monitoring as a potential target for improving neurological outcomes in extracorporeal life support.
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Affiliation(s)
- Nolan Chalifoux
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
| | - Tiffany Ko
- Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Julia Slovis
- Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Audrey Spelde
- Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Todd Kilbaugh
- Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Constantine D Mavroudis
- Division of Cardiothoracic Surgery, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA
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11
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Carlson AP, Jones T, Zhu Y, Desai M, Alsarah A, Shuttleworth CW. Oxygen-based autoregulation indices associated with clinical outcomes and spreading depolarization in aSAH. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.05.17.24307563. [PMID: 38798620 PMCID: PMC11118627 DOI: 10.1101/2024.05.17.24307563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Background Impairment in cerebral autoregulation has been proposed as a potentially targetable factor in patients with aneurysmal subarachnoid hemorrhage (aSAH), however there are different continuous measures that can be used to calculate the state of autoregulation. In addition, it has previously been proposed that there may be an association of impaired autoregulation with the occurrence of spreading depolarization (SD) events. Methods Subjects with invasive multimodal monitoring and aSAH were enrolled in an observational study. Autoregulation indices were prospectively calculated from this database as a 10 second moving correlation coefficient between various cerebral blood flow (CBF) surrogates and mean arterial pressure (MAP). In subjects with subdural ECoG (electrocorticography) monitoring, SD was also scored. Associations between clinical outcomes using the mRS (modified Rankin Scale) and occurrence of either isolated or clustered SD was assessed. Results 320 subjects were included, 47 of whom also had ECoG SD monitoring. As expected, baseline severity factors such as mFS and WFNS (World Federation of Neurosurgical Societies scale) were strongly associated with the clinical outcome. SD probability was related to blood pressure in a triphasic pattern with a linear increase in probability below MAP of ∼100mmHg.Autoregulation indices were available for intracranial pressure (ICP) measurements (PRx), PbtO2 from Licox (ORx), perfusion from the Bowman perfusion probe (CBFRx), and cerebral oxygen saturation measured by near infrared spectroscopy (OSRx). Only worse ORx and OSRx were associated with worse clinical outcomes. ORx and OSRx also were found to both increase in the hour prior to SD for both sporadic and clustered SD. Conclusions Impairment in autoregulation in aSAH is associated with worse clinical outcomes and occurrence of SD when using ORx and OSRx. Impaired autoregulation precedes SD occurrence. Targeting the optimal MAP or cerebral perfusion pressure in patients with aSAH should use ORx and/or OSRx as the input function rather than intracranial pressure.
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12
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Smith CA, Kazimierska A, Placek MM, Beqiri E, Karvandi E, Czosnyka M, Helmy A, Smielewski P. Transmission of slow waves in Masimo O 3 near infrared spectroscopy measures. BRAIN & SPINE 2024; 4:102834. [PMID: 38784127 PMCID: PMC11112281 DOI: 10.1016/j.bas.2024.102834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 04/22/2024] [Accepted: 05/08/2024] [Indexed: 05/25/2024]
Abstract
Introduction Cerebral autoregulation (CA) dysfunction is a key complication following brain injury. CA assessment using near-infrared spectroscopy (NIRS) offers a promising alternative to the current non-invasive standard, cerebral blood flow velocity (CBFV) measured with transcranial Doppler. Research question Can autoregulatory slow waves (frequency range 0.005-0.05 Hz) associated with spontaneous and induced changes in ABP in healthy volunteers be detected by parameters measured with the Masimo O3 NIRS device? Methods ABP, CBFV and Masimo O3 parameters were measured in 10 healthy volunteers at baseline and during ABP oscillations induced by squat/stand manoeuvres. Transmission of slow waves was assessed with power spectral density and coherence analysis in NIRS signals and compared to that of CBFV. Results At baseline, slow waves were detected with sufficient power that substantially exceeded the signals' measurement resolution in all parameters except cerebral oxygen saturation. During ABP oscillations in the 0.033 Hz range (induced by squat/stand), the power of slow waves increased in all parameters in a similar pattern, with total (cHb) and oxygenated (O2Hb) haemoglobin concentrations most closely mirroring CBFV (median standardised power [first-third quartile], baseline vs squat/stand: CBFV 0.35 [0.28-0.42] vs 0.50 [0.45-0.62], O2Hb 0.47 [0.33-0.68] vs 0.61 [0.59-0.69]). Coherence with ABP increased for both CBFV and NIRS measures from low at baseline (<0.4) to high during induced changes (>0.8). Conclusion Spontaneous fluctuations in ABP can be observed in analysed Masimo O3 metrics to a varying degree. The clinical utility of Masimo O3 signals in CA assessment requires further investigation in brain injury patients.
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Affiliation(s)
- Claudia A. Smith
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Agnieszka Kazimierska
- Department of Biomedical Engineering, Wrocław University of Science and Technology, Wrocław, Poland
| | - Michał M. Placek
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Erta Beqiri
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Elika Karvandi
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Marek Czosnyka
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Adel Helmy
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Peter Smielewski
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
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13
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Lengyel B, Magyar-Stang R, Pál H, Debreczeni R, Sándor ÁD, Székely A, Gyürki D, Csippa B, István L, Kovács I, Sótonyi P, Mihály Z. Non-Invasive Tools in Perioperative Stroke Risk Assessment for Asymptomatic Carotid Artery Stenosis with a Focus on the Circle of Willis. J Clin Med 2024; 13:2487. [PMID: 38731014 PMCID: PMC11084304 DOI: 10.3390/jcm13092487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/17/2024] [Accepted: 04/20/2024] [Indexed: 05/13/2024] Open
Abstract
This review aims to explore advancements in perioperative ischemic stroke risk estimation for asymptomatic patients with significant carotid artery stenosis, focusing on Circle of Willis (CoW) morphology based on the CTA or MR diagnostic imaging in the current preoperative diagnostic algorithm. Functional transcranial Doppler (fTCD), near-infrared spectroscopy (NIRS), and optical coherence tomography angiography (OCTA) are discussed in the context of evaluating cerebrovascular reserve capacity and collateral vascular systems, particularly the CoW. These non-invasive diagnostic tools provide additional valuable insights into the cerebral perfusion status. They support biomedical modeling as the gold standard for the prediction of the potential impact of carotid artery stenosis on the hemodynamic changes of cerebral perfusion. Intraoperative risk assessment strategies, including selective shunting, are explored with a focus on CoW variations and their implications for perioperative ischemic stroke and cognitive function decline. By synthesizing these insights, this review underscores the potential of non-invasive diagnostic methods to support clinical decision making and improve asymptomatic patient outcomes by reducing the risk of perioperative ischemic neurological events and preventing further cognitive decline.
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Affiliation(s)
- Balázs Lengyel
- Department of Vascular and Endovascular Surgery, Heart and Vascular Center, Semmelweis University, 1122 Budapest, Hungary; (B.L.); (P.S.J.)
| | - Rita Magyar-Stang
- Department of Neurology, Semmelweis University, 1085 Budapest, Hungary; (R.M.-S.); (H.P.); (R.D.)
- Szentágothai Doctoral School of Neurosciences, Semmelweis University, 1085 Budapest, Hungary
| | - Hanga Pál
- Department of Neurology, Semmelweis University, 1085 Budapest, Hungary; (R.M.-S.); (H.P.); (R.D.)
- Szentágothai Doctoral School of Neurosciences, Semmelweis University, 1085 Budapest, Hungary
| | - Róbert Debreczeni
- Department of Neurology, Semmelweis University, 1085 Budapest, Hungary; (R.M.-S.); (H.P.); (R.D.)
- Szentágothai Doctoral School of Neurosciences, Semmelweis University, 1085 Budapest, Hungary
| | - Ágnes Dóra Sándor
- Department of Anesthesiology and Intensive Therapy, Semmelweis University, 1085 Budapest, Hungary; (Á.D.S.); (A.S.)
| | - Andrea Székely
- Department of Anesthesiology and Intensive Therapy, Semmelweis University, 1085 Budapest, Hungary; (Á.D.S.); (A.S.)
| | - Dániel Gyürki
- Department of Hydrodynamic Systems, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, 1085 Budapest, Hungary; (D.G.); (B.C.)
| | - Benjamin Csippa
- Department of Hydrodynamic Systems, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, 1085 Budapest, Hungary; (D.G.); (B.C.)
| | - Lilla István
- Department of Ophthalmology, Semmelweis University, 1085 Budapest, Hungary; (L.I.); (I.K.)
| | - Illés Kovács
- Department of Ophthalmology, Semmelweis University, 1085 Budapest, Hungary; (L.I.); (I.K.)
- Department of Ophthalmology, Weill Cornell Medical College, New York, NY 10065, USA
- Department of Clinical Ophthalmology, Faculty of Health Sciences, Semmelweis University, 1085 Budapest, Hungary
| | - Péter Sótonyi
- Department of Vascular and Endovascular Surgery, Heart and Vascular Center, Semmelweis University, 1122 Budapest, Hungary; (B.L.); (P.S.J.)
| | - Zsuzsanna Mihály
- Department of Vascular and Endovascular Surgery, Heart and Vascular Center, Semmelweis University, 1122 Budapest, Hungary; (B.L.); (P.S.J.)
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14
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Crippa IA, Vincent JL, Zama Cavicchi F, Pozzebon S, Gaspard N, Maenhout C, Creteur J, Taccone FS. Estimated Cerebral Perfusion Pressure and Intracranial Pressure in Septic Patients. Neurocrit Care 2024; 40:577-586. [PMID: 37420137 DOI: 10.1007/s12028-023-01783-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 06/09/2023] [Indexed: 07/09/2023]
Abstract
BACKGROUND Sepsis-associated brain dysfunction (SABD) is frequent and is associated with poor outcome. Changes in brain hemodynamics remain poorly described in this setting. The aim of this study was to investigate the alterations of cerebral perfusion pressure and intracranial pressure in a cohort of septic patients. METHODS We conducted a retrospective analysis of prospectively collected data in septic adults admitted to our intensive care unit (ICU). We included patients in whom transcranial Doppler recording performed within 48 h from diagnosis of sepsis was available. Exclusion criteria were intracranial disease, known vascular stenosis, cardiac arrhythmias, pacemaker, mechanical cardiac support, severe hypotension, and severe hypocapnia or hypercapnia. SABD was clinically diagnosed by the attending physician, anytime during the ICU stay. Estimated cerebral perfusion pressure (eCPP) and estimated intracranial pressure (eICP) were calculated from the blood flow velocity of the middle cerebral artery and invasive arterial pressure using a previously validated formula. Normal eCPP was defined as eCPP ≥ 60 mm Hg, low eCPP was defined as eCPP < 60 mm Hg; normal eICP was defined as eICP ≤ 20 mm Hg, and high eICP was defined as eICP > 20 mm Hg. RESULTS A total of 132 patients were included in the final analysis (71% male, median [interquartile range (IQR)] age was 64 [52-71] years, median [IQR] Acute Physiology and Chronic Health Evaluation II score on admission was 21 [15-28]). Sixty-nine (49%) patients developed SABD during the ICU stay, and 38 (29%) were dead at hospital discharge. Transcranial Doppler recording lasted 9 (IQR 7-12) min. Median (IQR) eCPP was 63 (58-71) mm Hg in the cohort; 44 of 132 (33%) patients had low eCPP. Median (IQR) eICP was 8 (4-13) mm Hg; five (4%) patients had high eICP. SABD occurrence and in-hospital mortality did not differ between patients with normal eCPP and patients with low eCPP or between patients with normal eICP and patients with high eICP. Eighty-six (65%) patients had normal eCPP and normal eICP, 41 (31%) patients had low eCPP and normal eICP, three (2%) patients had low eCPP and high eICP, and two (2%) patients had normal eCPP and high eICP; however, SABD occurrence and in-hospital mortality were not significantly different among these subgroups. CONCLUSIONS Brain hemodynamics, in particular CPP, were altered in one third of critically ill septic patients at a steady state of monitoring performed early during the course of sepsis. However, these alterations were equally common in patients who developed or did not develop SABD during the ICU stay and in patients with favorable or unfavorable outcome.
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Affiliation(s)
- Ilaria Alice Crippa
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik 808, 1070, Brussels, Belgium.
- Department of Anesthesiology and Intensive Care, Policlinico San Marco, Gruppo San Donato, Corso Europa 7, 24046, Zingonia, Italy.
| | - Jean-Louis Vincent
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik 808, 1070, Brussels, Belgium
| | - Federica Zama Cavicchi
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik 808, 1070, Brussels, Belgium
| | - Selene Pozzebon
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik 808, 1070, Brussels, Belgium
| | - Nicolas Gaspard
- Department of Neurology, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik 808, 1070, Brussels, Belgium
| | - Christelle Maenhout
- Department of Neurology, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik 808, 1070, Brussels, Belgium
| | - Jacques Creteur
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik 808, 1070, Brussels, Belgium
| | - Fabio Silvio Taccone
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik 808, 1070, Brussels, Belgium
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15
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Olsen MH, Riberholt CG, Berg RMG, Møller K. Myths and methodologies: Assessment of dynamic cerebral autoregulation by the mean flow index. Exp Physiol 2024; 109:614-623. [PMID: 38376110 PMCID: PMC10988760 DOI: 10.1113/ep091327] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 01/17/2024] [Indexed: 02/21/2024]
Abstract
The mean flow index-usually referred to as Mx-has been used for assessing dynamic cerebral autoregulation (dCA) for almost 30 years. However, concerns have arisen regarding methodological consistency, construct and criterion validity, and test-retest reliability. Methodological nuances, such as choice of input (cerebral perfusion pressure, invasive or non-invasive arterial pressure), pre-processing approach and artefact handling, significantly influence mean flow index values, and previous studies correlating mean flow index with other established dCA metrics are confounded by inherent methodological flaws like heteroscedasticity, while the mean flow index also fails to discriminate individuals with presumed intact versus impaired dCA (discriminatory validity), and its prognostic performance (predictive validity) across various conditions remains inconsistent. The test-retest reliability, both within and between days, is generally poor. At present, no single approach for data collection or pre-processing has proven superior for obtaining the mean flow index, and caution is advised in the further use of mean flow index-based measures for assessing dCA, as current evidence does not support their clinical application.
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Affiliation(s)
- Markus Harboe Olsen
- Department of Neuroanaesthesiology, The Neuroscience CentreCopenhagen University Hospital − RigshospitaletCopenhagenDenmark
| | - Christian Gunge Riberholt
- Department of Neuroanaesthesiology, The Neuroscience CentreCopenhagen University Hospital − RigshospitaletCopenhagenDenmark
- Department of Brain and Spinal Cord Injury, The Neuroscience CentreCopenhagen University Hospital − RigshospitaletCopenhagenDenmark
| | - Ronan M. G. Berg
- Department of Clinical Physiology and Nuclear MedicineCopenhagen University Hospital − RigshospitaletCopenhagenDenmark
- Centre for Physical Activity ResearchCopenhagen University Hospital − RigshospitaletCopenhagenDenmark
- Department of Biomedical Sciences, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesPontypriddUK
| | - Kirsten Møller
- Department of Neuroanaesthesiology, The Neuroscience CentreCopenhagen University Hospital − RigshospitaletCopenhagenDenmark
- Department of Clinical Medicine, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
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16
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Llompart-Pou JA, Galarza L, Amaya-Villar R, Godoy DA. Transcranial sonography in the critical patient. Med Intensiva 2024; 48:165-173. [PMID: 38431382 DOI: 10.1016/j.medine.2023.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 06/09/2023] [Indexed: 03/05/2024]
Abstract
Transcranial ultrasonography is a non-invasive, bedside technique that has become a widely implemented tool in the evaluation and management of neurocritically ill patients. It constitutes a technique in continuous growth whose fundamentals (and limitations) must be known by the intensivist. This review provides a practical approach for the intensivist, including the different sonographic windows and planes of insonation and its role in different conditions of the neurocritical patients and in critical care patients of other etiologies.
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Affiliation(s)
- Juan Antonio Llompart-Pou
- Servei de Medicina Intensiva, Hospital Universitari Son Espases, Institut d'Investigació Sanitària Illes Balears (IdISBa), Palma, Spain.
| | - Laura Galarza
- Servicio de Medicina Intensiva, Hospital General Universitario de Castellón, Castellón de la Plana, Spain
| | - Rosario Amaya-Villar
- Unidad Clínica de Cuidados Intensivos, Hospital Universitario Virgen del Rocío, Sevilla, Spain
| | - Daniel Agustín Godoy
- Unidad de Cuidados Neurointensivos, Sanatorio Pasteur, San Fernando del Valle de Catamarca, Argentina
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17
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Agrawal S, Abecasis F, Jalloh I. Neuromonitoring in Children with Traumatic Brain Injury. Neurocrit Care 2024; 40:147-158. [PMID: 37386341 PMCID: PMC10861621 DOI: 10.1007/s12028-023-01779-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 06/05/2023] [Indexed: 07/01/2023]
Abstract
Traumatic brain injury remains a major cause of mortality and morbidity in children across the world. Current management based on international guidelines focuses on a fixed therapeutic target of less than 20 mm Hg for managing intracranial pressure and 40-50 mm Hg for cerebral perfusion pressure across the pediatric age group. To improve outcome from this complex disease, it is essential to understand the pathophysiological mechanisms responsible for disease evolution by using different monitoring tools. In this narrative review, we discuss the neuromonitoring tools available for use to help guide management of severe traumatic brain injury in children and some of the techniques that can in future help with individualizing treatment targets based on advanced cerebral physiology monitoring.
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Affiliation(s)
- Shruti Agrawal
- Department of Paediatric Intensive Care, Cambridge University Hospitals National Health Service Foundation Trust, Level 3, Box 7, Addenbrookes Hospital Hills Road, Cambridge, UK.
- University of Cambridge, Cambridge, UK.
| | - Francisco Abecasis
- Paediatric Intensive Care Unit, Centro Hospitalar Universitário Lisboa Norte, Lisbon, Portugal
| | - Ibrahim Jalloh
- University of Cambridge, Cambridge, UK
- Department of Neurosurgery, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge, UK
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18
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Hirsch KG, Abella BS, Amorim E, Bader MK, Barletta JF, Berg K, Callaway CW, Friberg H, Gilmore EJ, Greer DM, Kern KB, Livesay S, May TL, Neumar RW, Nolan JP, Oddo M, Peberdy MA, Poloyac SM, Seder D, Taccone FS, Uzendu A, Walsh B, Zimmerman JL, Geocadin RG. Critical Care Management of Patients After Cardiac Arrest: A Scientific Statement from the American Heart Association and Neurocritical Care Society. Neurocrit Care 2024; 40:1-37. [PMID: 38040992 PMCID: PMC10861627 DOI: 10.1007/s12028-023-01871-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 06/08/2023] [Indexed: 12/03/2023]
Abstract
The critical care management of patients after cardiac arrest is burdened by a lack of high-quality clinical studies and the resultant lack of high-certainty evidence. This results in limited practice guideline recommendations, which may lead to uncertainty and variability in management. Critical care management is crucial in patients after cardiac arrest and affects outcome. Although guidelines address some relevant topics (including temperature control and neurological prognostication of comatose survivors, 2 topics for which there are more robust clinical studies), many important subject areas have limited or nonexistent clinical studies, leading to the absence of guidelines or low-certainty evidence. The American Heart Association Emergency Cardiovascular Care Committee and the Neurocritical Care Society collaborated to address this gap by organizing an expert consensus panel and conference. Twenty-four experienced practitioners (including physicians, nurses, pharmacists, and a respiratory therapist) from multiple medical specialties, levels, institutions, and countries made up the panel. Topics were identified and prioritized by the panel and arranged by organ system to facilitate discussion, debate, and consensus building. Statements related to postarrest management were generated, and 80% agreement was required to approve a statement. Voting was anonymous and web based. Topics addressed include neurological, cardiac, pulmonary, hematological, infectious, gastrointestinal, endocrine, and general critical care management. Areas of uncertainty, areas for which no consensus was reached, and future research directions are also included. Until high-quality studies that inform practice guidelines in these areas are available, the expert panel consensus statements that are provided can advise clinicians on the critical care management of patients after cardiac arrest.
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Affiliation(s)
| | | | - Edilberto Amorim
- San Francisco-Weill Institute for Neurosciences, University of California, San Francisco, USA
| | - Mary Kay Bader
- Providence Mission Hospital Nursing Center of Excellence/Critical Care Services, Mission Viejo, USA
| | | | | | | | | | | | | | - Karl B Kern
- Sarver Heart Center, University of Arizona, Tucson, USA
| | | | | | | | - Jerry P Nolan
- Warwick Medical School, University of Warwick, Coventry, UK
- Royal United Hospital, Bath, UK
| | - Mauro Oddo
- CHUV-Lausanne University Hospital, Lausanne, Switzerland
| | | | | | | | | | - Anezi Uzendu
- St. Luke's Mid America Heart Institute, Kansas City, USA
| | - Brian Walsh
- University of Texas Medical Branch School of Health Sciences, Galveston, USA
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19
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Hirsch KG, Abella BS, Amorim E, Bader MK, Barletta JF, Berg K, Callaway CW, Friberg H, Gilmore EJ, Greer DM, Kern KB, Livesay S, May TL, Neumar RW, Nolan JP, Oddo M, Peberdy MA, Poloyac SM, Seder D, Taccone FS, Uzendu A, Walsh B, Zimmerman JL, Geocadin RG. Critical Care Management of Patients After Cardiac Arrest: A Scientific Statement From the American Heart Association and Neurocritical Care Society. Circulation 2024; 149:e168-e200. [PMID: 38014539 PMCID: PMC10775969 DOI: 10.1161/cir.0000000000001163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
The critical care management of patients after cardiac arrest is burdened by a lack of high-quality clinical studies and the resultant lack of high-certainty evidence. This results in limited practice guideline recommendations, which may lead to uncertainty and variability in management. Critical care management is crucial in patients after cardiac arrest and affects outcome. Although guidelines address some relevant topics (including temperature control and neurological prognostication of comatose survivors, 2 topics for which there are more robust clinical studies), many important subject areas have limited or nonexistent clinical studies, leading to the absence of guidelines or low-certainty evidence. The American Heart Association Emergency Cardiovascular Care Committee and the Neurocritical Care Society collaborated to address this gap by organizing an expert consensus panel and conference. Twenty-four experienced practitioners (including physicians, nurses, pharmacists, and a respiratory therapist) from multiple medical specialties, levels, institutions, and countries made up the panel. Topics were identified and prioritized by the panel and arranged by organ system to facilitate discussion, debate, and consensus building. Statements related to postarrest management were generated, and 80% agreement was required to approve a statement. Voting was anonymous and web based. Topics addressed include neurological, cardiac, pulmonary, hematological, infectious, gastrointestinal, endocrine, and general critical care management. Areas of uncertainty, areas for which no consensus was reached, and future research directions are also included. Until high-quality studies that inform practice guidelines in these areas are available, the expert panel consensus statements that are provided can advise clinicians on the critical care management of patients after cardiac arrest.
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20
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Soehle M. Fractal Analysis of the Cerebrovascular System Pathophysiology. ADVANCES IN NEUROBIOLOGY 2024; 36:385-396. [PMID: 38468043 DOI: 10.1007/978-3-031-47606-8_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
The cerebrovascular system is characterized by parameters such as arterial blood pressure (ABP), cerebral perfusion pressure (CPP), and cerebral blood flow velocity (CBFV). These are regulated by interconnected feedback loops resulting in a fluctuating and complex time course. They exhibit fractal characteristics such as (statistical) self-similarity and scale invariance which could be quantified by fractal measures. These include the coefficient of variation, the Hurst coefficient H, or the spectral exponent α in the time domain, as well as the spectral index ß in the frequency domain. Prior to quantification, the time series has to be classified as either stationary or nonstationary, which determines the appropriate fractal analysis and measure for a given signal class. CBFV was characterized as a nonstationary (fractal Brownian motion) signal with spectral index ß between 2.0 and 2.3. In the high-frequency range (>0.15 Hz), CBFV variability is mainly determined by the periodic ABP variability induced by heartbeat and respiration. However, most of the spectral power of CBFV is contained in the low-frequency range (<0.15 Hz), where cerebral autoregulation acts as a low-pass filter and where the fractal properties are found. Cerebral vasospasm, which is a complication of subarachnoid hemorrhage (SAH), is associated with an increase in ß denoting a less complex time course. A reduced fractal dimension of the retinal microvasculature has been observed in neurodegenerative disease and in stroke. According to the decomplexification theory of illness, such a diminished complexity could be explained by a restriction or even dropout of feedback loops caused by disease.
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Affiliation(s)
- Martin Soehle
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Bonn, Bonn, Germany.
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Burzyńska M, Uryga A, Kasprowicz M, Czosnyka M, Goździk W, Robba C. Cerebral Autoregulation, Cerebral Hemodynamics, and Injury Biomarkers, in Patients with COVID-19 Treated with Veno-Venous Extracorporeal Membrane Oxygenation. Neurocrit Care 2023; 39:425-435. [PMID: 36949359 PMCID: PMC10033181 DOI: 10.1007/s12028-023-01700-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 02/14/2023] [Indexed: 03/24/2023]
Abstract
BACKGROUND This study aimed to describe the cerebrovascular dynamics, in particular cerebral autoregulation (CA), and cerebral biomarkers as neuron-specific enolase (NSE) in patients with a diagnosis of coronavirus disease 2019 and acute respiratory distress syndrome as well as undergoing veno-venous extracorporeal membrane treatment. METHODS This was a single center, observational study conducted in the intensive care unit of the University Hospital in Wroclaw from October 2020 to February 2022. Transcranial Doppler recordings of the middle cerebral artery conducted for at least 20 min were performed. Cerebral autoregulation (CA) was estimated by using the mean velocity index (Mxa), calculated as the moving correlation coefficient between slow-wave oscillations in cerebral blood flow velocity and arterial blood pressure. Altered CA was defined as a positive Mxa. Blood samples for the measurement of NSE were obtained at the same time as transcranial Doppler measurements. RESULTS A total of 16 patients fulfilled the inclusion criteria and were enrolled in the study. The median age was 39 (34-56) years. Altered CA was found in 12 patients, and six out of seven patients who died had altered CA. A positive Mxa was a significant predictor of mortality, with a sensitivity of 85.7%. We found that three out of five patients with pathological changes in brain computed tomography and six out of ten patients with neurological complications had altered CA. NSE was a significant predictor of mortality (cutoff value: 28.9 µg/L); area under the curve = 0.83, p = 0.006), with a strong relationship between increased level of NSE and altered CA, χ2 = 6.24; p = 0.035; φ = 0.69. CONCLUSIONS Patients with coronavirus disease 2019-related acute respiratory distress syndrome, requiring veno-venous extracorporeal membrane treatment, are likely to have elevated NSE levels and altered CA. The CA was associated with NSE values in this group. This preliminary analysis suggests that advanced neuromonitoring and evaluation of biomarkers should be considered in this population.
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Affiliation(s)
- Małgorzata Burzyńska
- Department of Anaesthesiology and Intensive Care, Wroclaw Medical University, Wroclaw, Poland
| | - Agnieszka Uryga
- Department of Biomedical Engineering, Faculty of Fundamental Problems of Technology, Wroclaw University of Science and Technology, Wybrzeze Wyspianskiego 27, 50-370, Wroclaw, Poland.
| | - Magdalena Kasprowicz
- Department of Biomedical Engineering, Faculty of Fundamental Problems of Technology, Wroclaw University of Science and Technology, Wybrzeze Wyspianskiego 27, 50-370, Wroclaw, Poland
| | - Marek Czosnyka
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
- Institute of Electronic Systems, Faculty of Electronics and Information Technology, Warsaw University of Technology, Warsaw, Poland
| | - Waldemar Goździk
- Department of Anaesthesiology and Intensive Care, Wroclaw Medical University, Wroclaw, Poland
| | - Chiara Robba
- IRCCS, Ospedale Policlinico San Martino, Genoa, Italy
- Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Viale Benedetto XV 16, Genoa, Italy
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Oshorov A, Gavrjushin A, Savin I, Alexandrova E, Bragin D. Comparison of Cerebral Autoregulation Above and Below the Tentorium of the Cerebellum In Neurosurgical Patients with Transtentorial ICP Gradient. Neurocrit Care 2023; 39:419-424. [PMID: 36890339 PMCID: PMC10485174 DOI: 10.1007/s12028-023-01696-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 02/09/2023] [Indexed: 03/10/2023]
Abstract
INTRODUCTION Cerebral autoregulation is an essential mechanism for maintaining cerebral blood flow stability. The phenomenon of transtentorial intracranial pressure (ICP) gradient after neurosurgical operations, complicated by edema and intracranial hypertension in the posterior fossa, has been described in clinical practice but is still underinvestigated. The aim of the study was to compare autoregulation coefficients (i.e., pressure reactivity index [PRx]) in two compartments (infratentorial and supratentorial) during the ICP gradient phenomenon. METHODS Three male patients, aged 24 years, 32 years, and 59 years, respectively, were involved in the study after posterior fossa surgery. Arterial blood pressure and ICP were invasively monitored. Infratentorial ICP was measured in the cerebellar parenchyma. Supratentorial ICP was measured either in the parenchyma of the cerebral hemispheres or through the external ventricular drainage. Cerebral autoregulation was evaluated by the PRx coefficient (ICM + , Cambridge, UK). RESULTS In all patients, ICP was higher in the posterior fossa, and the transtentorial ICP gradient in each patient was 5 ± 1.6 mm Hg, 8.5 ± 4.4 mm Hg, and 7.7 ± 2.2 mm Hg, respectively. ICP in the infratentorial space was 17 ± 4 mm Hg, 18 ± 4.4 mm Hg, and 20 ± 4 mm Hg, respectively. PRx values in the supratentorial and infratentorial spaces had the smallest difference (- 0.01, 0.02, and 0.01, respectively), and the limits of precision were 0.1, 0.2, and 0.1 in the first, second, and third patients, respectively. The correlation coefficient between the PRx values in the supratentorial and infratentorial spaces for each patient was 0.98, 0.95, and 0.97, respectively. CONCLUSIONS A high degree of correlation was established between the autoregulation coefficient PRx in two compartments in the presence of transtentorial ICP gradient and persistent intracranial hypertension in the posterior fossa. Cerebral autoregulation, according to the PRx coefficient in both spaces, was similar.
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Affiliation(s)
- Andrey Oshorov
- Burdenko Neurosurgery Institute, 4-Ya Tverskaya-Yamskaya Str, 16, Moscow, Russia, 125047.
| | - Andrey Gavrjushin
- Burdenko Neurosurgery Institute, 4-Ya Tverskaya-Yamskaya Str, 16, Moscow, Russia, 125047
| | - Ivan Savin
- Burdenko Neurosurgery Institute, 4-Ya Tverskaya-Yamskaya Str, 16, Moscow, Russia, 125047
| | - Evgenia Alexandrova
- Burdenko Neurosurgery Institute, 4-Ya Tverskaya-Yamskaya Str, 16, Moscow, Russia, 125047
| | - Denis Bragin
- Lovelace Biomedical Research Institute, Albuquerque, NM, USA
- Department of Neurology, University of New Mexico School of Medicine, Albuquerque, NM, USA
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Cucciolini G, Motroni V, Czosnyka M. Intracranial pressure for clinicians: it is not just a number. JOURNAL OF ANESTHESIA, ANALGESIA AND CRITICAL CARE 2023; 3:31. [PMID: 37670387 PMCID: PMC10481563 DOI: 10.1186/s44158-023-00115-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 08/16/2023] [Indexed: 09/07/2023]
Abstract
BACKGROUND Invasive intracranial pressure (ICP) monitoring is a standard practice in severe brain injury cases, where it allows to derive cerebral perfusion pressure (CPP); ICP-tracing can also provide additional information about intracranial dynamics, forecast episodes of intracranial hypertension and set targets for a tailored therapy to prevent secondary brain injury. Nevertheless, controversies about the advantages of an ICP clinical management are still debated. FINDINGS This article reviews recent research on ICP to improve the understanding of the topic and uncover the hidden information in this signal that may be useful in clinical practice. Parameters derived from time-domain as well as frequency domain analysis include compensatory reserve, autoregulation estimation, pulse waveform analysis, and behavior of ICP in time. The possibility to predict the outcome and apply a tailored therapy using a personalised perfusion pressure target is also described. CONCLUSIONS ICP is a crucial signal to monitor in severely brain injured patients; a bedside computer can empower standard monitoring giving new metrics that may aid in clinical management, establish a personalized therapy, and help to predict the outcome. Continuous collaboration between engineers and clinicians and application of new technologies to healthcare, is vital to improve the accuracy of current metrics and progress towards better care with individualized dynamic targets.
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Affiliation(s)
- Giada Cucciolini
- Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy.
- Department of Clinical Neurosciences, Division of Neurosurgery, Brain Physics Laboratory, University of Cambridge, Cambridge, UK.
| | - Virginia Motroni
- Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy
- Department of Clinical Neurosciences, Division of Neurosurgery, Brain Physics Laboratory, University of Cambridge, Cambridge, UK
| | - Marek Czosnyka
- Department of Clinical Neurosciences, Division of Neurosurgery, Brain Physics Laboratory, University of Cambridge, Cambridge, UK
- Institute of Electronic Systems, Warsaw University of Technology, Warsaw, Poland
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Sainbhi AS, Marquez I, Gomez A, Stein KY, Amenta F, Vakitbilir N, Froese L, Zeiler FA. Regional disparity in continuously measured time-domain cerebrovascular reactivity indices: a scoping review of human literature. Physiol Meas 2023; 44:07TR02. [PMID: 37336236 DOI: 10.1088/1361-6579/acdfb6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 06/19/2023] [Indexed: 06/21/2023]
Abstract
Objective: Cerebral blood vessels maintaining relatively constant cerebral blood flow (CBF) over wide range of systemic arterial blood pressure (ABP) is referred to as cerebral autoregulation (CA). Impairments in CA expose the brain to pressure-passive flow states leading to hypoperfusion and hyperperfusion. Cerebrovascular reactivity (CVR) metrics refer to surrogate metrics of pressure-based CA that evaluate the relationship between slow vasogenic fluctuations in cerebral perfusion pressure/ABP and a surrogate for pulsatile CBF/cerebral blood volume.Approach: We performed a systematically conducted scoping review of all available human literature examining the association between continuous CVR between more than one brain region/channel using the same CVR index.Main Results: In all the included 22 articles, only handful of transcranial doppler (TCD) and near-infrared spectroscopy (NIRS) based metrics were calculated for only two brain regions/channels. These metrics found no difference between left and right sides in healthy volunteer, cardiac surgery, and intracranial hemorrhage patient studies. In contrast, significant differences were reported in endarterectomy, and subarachnoid hemorrhage studies, while varying results were found regarding regional disparity in stroke, traumatic brain injury, and multiple population studies.Significance: Further research is required to evaluate regional disparity using NIRS-based indices and to understand if NIRS-based indices provide better regional disparity information than TCD-based indices.
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Affiliation(s)
- Amanjyot Singh Sainbhi
- Department of Biomedical Engineering, Price Faculty of Engineering, University of Manitoba, Winnipeg, Canada
| | - Izabella Marquez
- Undergraduate Engineering, Price Faculty of Engineering, University of Manitoba, Winnipeg, Canada
| | - Alwyn Gomez
- Section of Neurosurgery, Department of Surgery, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
| | - Kevin Y Stein
- Department of Biomedical Engineering, Price Faculty of Engineering, University of Manitoba, Winnipeg, Canada
| | - Fiorella Amenta
- Undergraduate Engineering, Price Faculty of Engineering, University of Manitoba, Winnipeg, Canada
| | - Nuray Vakitbilir
- Department of Biomedical Engineering, Price Faculty of Engineering, University of Manitoba, Winnipeg, Canada
| | - Logan Froese
- Department of Biomedical Engineering, Price Faculty of Engineering, University of Manitoba, Winnipeg, Canada
| | - Frederick A Zeiler
- Department of Biomedical Engineering, Price Faculty of Engineering, University of Manitoba, Winnipeg, Canada
- Section of Neurosurgery, Department of Surgery, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
- Centre on Aging, University of Manitoba, Winnipeg, Canada
- Division of Anaesthesia, Department of Medicine, Addenbrooke's Hospital, University of Cambridge, Cambridge, United Kingdom
- Department of Clinical Neurosciences, Karolinksa Institutet, Stockholm, Sweden
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25
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Kastenholz N, Megjhani M, Conzen-Dilger C, Albanna W, Veldeman M, Nametz D, Kwon SB, Schulze-Steinen H, Ridwan H, Clusmann H, Schubert GA, Park S, Weiss M. The oxygen reactivity index indicates disturbed local perfusion regulation after aneurysmal subarachnoid hemorrhage: an observational cohort study. Crit Care 2023; 27:235. [PMID: 37312192 PMCID: PMC10265851 DOI: 10.1186/s13054-023-04452-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 04/19/2023] [Indexed: 06/15/2023] Open
Abstract
BACKGROUND Cerebral autoregulation (CA) can be impaired in patients with delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH). The Pressure Reactivity Index (PRx, correlation of blood pressure and intracranial pressure) and Oxygen Reactivity Index (ORx, correlation of cerebral perfusion pressure and brain tissue oxygenation, PbtO2) are both believed to estimate CA. We hypothesized that CA could be poorer in hypoperfused territories during DCI and that ORx and PRx may not be equally effective in detecting such local variances. METHODS ORx and PRx were compared daily in 76 patients with aSAH with or without DCI until the time of DCI diagnosis. The ICP/PbtO2-probes of DCI patients were retrospectively stratified by being in or outside areas of hypoperfusion via CT perfusion image, resulting in three groups: DCI + /probe + (DCI patients, probe located inside the hypoperfused area), DCI + /probe- (probe outside the hypoperfused area), DCI- (no DCI). RESULTS PRx and ORx were not correlated (r = - 0.01, p = 0.56). Mean ORx but not PRx was highest when the probe was located in a hypoperfused area (ORx DCI + /probe + 0.28 ± 0.13 vs. DCI + /probe- 0.18 ± 0.15, p < 0.05; PRx DCI + /probe + 0.12 ± 0.17 vs. DCI + /probe- 0.06 ± 0.20, p = 0.35). PRx detected poorer autoregulation during the early phase with relatively higher ICP (days 1-3 after hemorrhage) but did not differentiate the three groups on the following days when ICP was lower on average. ORx was higher in the DCI + /probe + group than in the other two groups from day 3 onward. ORx and PRx did not differ between patients with DCI, whose probe was located elsewhere, and patients without DCI (ORx DCI + /probe- 0.18 ± 0.15 vs. DCI- 0.20 ± 0.14; p = 0.50; PRx DCI + /probe- 0.06 ± 0.20 vs. DCI- 0.08 ± 0.17, p = 0.35). CONCLUSIONS PRx and ORx are not interchangeable measures of autoregulation, as they likely measure different homeostatic mechanisms. PRx represents the classical cerebrovascular reactivity and might be better suited to detect disturbed autoregulation during phases with moderately elevated ICP. Autoregulation may be poorer in territories affected by DCI. These local perfusion disturbances leading up to DCI may be more readily detected by ORx than PRx. Further research should investigate their robustness to detect DCI and to serve as a basis for autoregulation-targeted treatment after aSAH.
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Affiliation(s)
- Nick Kastenholz
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
- Program for Hospital and Intensive Care Informatics, Department of Neurology, Columbia University Vagelos College of Physicians and Surgeons, New York City, NY, USA
- NewYork-Presbyterian Hospital, Columbia University Irving Medical Center, New York City, NY, USA
| | - Murad Megjhani
- Program for Hospital and Intensive Care Informatics, Department of Neurology, Columbia University Vagelos College of Physicians and Surgeons, New York City, NY, USA
- NewYork-Presbyterian Hospital, Columbia University Irving Medical Center, New York City, NY, USA
| | | | - Walid Albanna
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
| | - Michael Veldeman
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
| | - Daniel Nametz
- Program for Hospital and Intensive Care Informatics, Department of Neurology, Columbia University Vagelos College of Physicians and Surgeons, New York City, NY, USA
- NewYork-Presbyterian Hospital, Columbia University Irving Medical Center, New York City, NY, USA
| | - Soon Bin Kwon
- Program for Hospital and Intensive Care Informatics, Department of Neurology, Columbia University Vagelos College of Physicians and Surgeons, New York City, NY, USA
- NewYork-Presbyterian Hospital, Columbia University Irving Medical Center, New York City, NY, USA
| | - Henna Schulze-Steinen
- Department of Intensive Care Medicine and Perioperative Care, RWTH Aachen University, Aachen, Germany
| | - Hani Ridwan
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Aachen, Germany
| | - Hans Clusmann
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
| | - Gerrit Alexander Schubert
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
- Department of Neurosurgery, Cantonal Hospital Aarau, Tellstrasse 25, 5001, Aarau, Switzerland
| | - Soojin Park
- Program for Hospital and Intensive Care Informatics, Department of Neurology, Columbia University Vagelos College of Physicians and Surgeons, New York City, NY, USA
- NewYork-Presbyterian Hospital, Columbia University Irving Medical Center, New York City, NY, USA
- Department of Biomedical Informatics, Columbia University, New York City, NY, USA
| | - Miriam Weiss
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany.
- Department of Neurosurgery, Cantonal Hospital Aarau, Tellstrasse 25, 5001, Aarau, Switzerland.
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dos Santos KRM, Katsidoniotaki MI, Miller EC, Petersen NH, Marshall RS, Kougioumtzoglou IA. Reduced-order modeling and analysis of dynamic cerebral autoregulation via diffusion maps. Physiol Meas 2023; 44:10.1088/1361-6579/acc780. [PMID: 36963111 PMCID: PMC11271258 DOI: 10.1088/1361-6579/acc780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 03/24/2023] [Indexed: 03/26/2023]
Abstract
Objective.A data-driven technique for parsimonious modeling and analysis of dynamic cerebral autoregulation (DCA) is developed based on the concept of diffusion maps. Specifically, first, a state-space description of DCA dynamics is considered based on arterial blood pressure, cerebral blood flow velocity, and their time derivatives. Next, an eigenvalue analysis of the Markov matrix of a random walk on a graph over the dataset domain yields a low-dimensional representation of the intrinsic dynamics. Further dimension reduction is made possible by accounting only for the two most significant eigenvalues. The value of their ratio indicates whether the underlying system is governed by active or hypoactive dynamics, indicating healthy or impaired DCA function, respectively. We assessed the reliability of the technique by considering healthy individuals and patients with unilateral internal carotid artery (ICA) stenosis or occlusion. We computed the sensitivity of the technique to detect the presumed side-to-side difference in the DCA function of the second group (assuming hypoactive dynamics on the occluded or stenotic side), using McNemar's chi square test. The results were compared with transfer function analysis (TFA). The performance of the two methods was also compared under the assumption of missing data.Main results.Both diffusion maps and TFA suggested a physiological side-to-side difference in the DCA of ICA stenosis or occlusion patients with a sensitivity of 81% and 71%, respectively. Further, both two methods suggested the difference between the occluded or stenotic side and any two sides of the healthy group. However, the diffusion maps captured additional difference between the unoccluded side and the healthy group, that TFA did not. Furthermore, compared to TFA, diffusion maps exhibited superior performance when subject to missing data.Significance.The eigenvalues ratio derived using the diffusion maps technique can be potentially used as a reliable and robust biomarker for assessing how active the intrinsic dynamics of the autoregulation is and for indicating healthy versus impaired DCA function.
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Affiliation(s)
- K R M dos Santos
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota, Minneapolis, MN, United States of America
| | - M I Katsidoniotaki
- Department of Civil Engineering and Engineering Mechanics, Columbia University, New York, NY, United States of America
| | - E C Miller
- Neurology-Stroke Division, Neurological Institute of New York, Columbia University Medical Center, New York, NY, United States of America
| | - N H Petersen
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States of America
| | - R S Marshall
- Neurology-Stroke Division, Neurological Institute of New York, Columbia University Medical Center, New York, NY, United States of America
| | - I A Kougioumtzoglou
- Department of Civil Engineering and Engineering Mechanics, Columbia University, New York, NY, United States of America
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Müller SJ, Henkes E, Gounis MJ, Felber S, Ganslandt O, Henkes H. Non-Invasive Intracranial Pressure Monitoring. J Clin Med 2023; 12:jcm12062209. [PMID: 36983213 PMCID: PMC10051320 DOI: 10.3390/jcm12062209] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/09/2023] [Accepted: 03/11/2023] [Indexed: 03/15/2023] Open
Abstract
(1) Background: Intracranial pressure (ICP) monitoring plays a key role in the treatment of patients in intensive care units, as well as during long-term surgeries and interventions. The gold standard is invasive measurement and monitoring via ventricular drainage or a parenchymal probe. In recent decades, numerous methods for non-invasive measurement have been evaluated but none have become established in routine clinical practice. The aim of this study was to reflect on the current state of research and shed light on relevant techniques for future clinical application. (2) Methods: We performed a PubMed search for “non-invasive AND ICP AND (measurement OR monitoring)” and identified 306 results. On the basis of these search results, we conducted an in-depth source analysis to identify additional methods. Studies were analyzed for design, patient type (e.g., infants, adults, and shunt patients), statistical evaluation (correlation, accuracy, and reliability), number of included measurements, and statistical assessment of accuracy and reliability. (3) Results: MRI-ICP and two-depth Doppler showed the most potential (and were the most complex methods). Tympanic membrane temperature, diffuse correlation spectroscopy, natural resonance frequency, and retinal vein approaches were also promising. (4) Conclusions: To date, no convincing evidence supports the use of a particular method for non-invasive intracranial pressure measurement. However, many new approaches are under development.
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Affiliation(s)
- Sebastian Johannes Müller
- Neuroradiologische Klinik, Klinikum Stuttgart, D-70174 Stuttgart, Germany
- Correspondence: ; Tel.: +49-(0)711-278-34501
| | - Elina Henkes
- Neuroradiologische Klinik, Klinikum Stuttgart, D-70174 Stuttgart, Germany
| | - Matthew J. Gounis
- New England Center for Stroke Research, Department of Radiology, University of Massachusetts, Worcester, MA 01655, USA
| | - Stephan Felber
- Institut für Diagnostische und Interventionelle Radiologie und Neuroradiologie, Stiftungsklinikum Mittelrhein, D-56068 Koblenz, Germany
| | - Oliver Ganslandt
- Neurochirurgische Klinik, Klinikum Stuttgart, D-70174 Stuttgart, Germany
| | - Hans Henkes
- Neuroradiologische Klinik, Klinikum Stuttgart, D-70174 Stuttgart, Germany
- Medizinische Fakultät, Universität Duisburg-Essen, D-47057 Duisburg, Germany
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Wang J, Shi Y, Cao S, Liu X, Martin LJ, Simoni J, Soltys BJ, Hsia CJC, Koehler RC. Polynitroxylated PEGylated hemoglobin protects pig brain neocortical gray and white matter after traumatic brain injury and hemorrhagic shock. FRONTIERS IN MEDICAL TECHNOLOGY 2023; 5:1074643. [PMID: 36896342 PMCID: PMC9988926 DOI: 10.3389/fmedt.2023.1074643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 01/13/2023] [Indexed: 02/23/2023] Open
Abstract
Polynitroxylated PEGylated hemoglobin (PNPH, aka SanFlow) possesses superoxide dismutase/catalase mimetic activities that may directly protect the brain from oxidative stress. Stabilization of PNPH with bound carbon monoxide prevents methemoglobin formation during storage and permits it to serve as an anti-inflammatory carbon monoxide donor. We determined whether small volume transfusion of hyperoncotic PNPH is neuroprotective in a porcine model of traumatic brain injury (TBI) with and without accompanying hemorrhagic shock (HS). TBI was produced by controlled cortical impact over the frontal lobe of anesthetized juvenile pigs. Hemorrhagic shock was induced starting 5 min after TBI by 30 ml/kg blood withdrawal. At 120 min after TBI, pigs were resuscitated with 60 ml/kg lactated Ringer's (LR) or 10 or 20 ml/kg PNPH. Mean arterial pressure recovered to approximately 100 mmHg in all groups. A significant amount of PNPH was retained in the plasma over the first day of recovery. At 4 days of recovery in the LR-resuscitated group, the volume of frontal lobe subcortical white matter ipsilateral to the injury was 26.2 ± 7.6% smaller than homotypic contralateral volume, whereas this white matter loss was only 8.6 ± 12.0% with 20-ml/kg PNPH resuscitation. Amyloid precursor protein punctate accumulation, a marker of axonopathy, increased in ipsilateral subcortical white matter by 132 ± 71% after LR resuscitation, whereas the changes after 10 ml/kg (36 ± 41%) and 20 ml/kg (26 ± 15%) PNPH resuscitation were not significantly different from controls. The number of cortical neuron long dendrites enriched in microtubules (length >50 microns) decreased in neocortex by 41 ± 24% after LR resuscitation but was not significantly changed after PNPH resuscitation. The perilesion microglia density increased by 45 ± 24% after LR resuscitation but was unchanged after 20 ml/kg PNPH resuscitation (4 ± 18%). Furthermore, the number with an activated morphology was attenuated by 30 ± 10%. In TBI pigs without HS followed 2 h later by infusion of 10 ml/kg LR or PNPH, PNPH remained neuroprotective. These results in a gyrencephalic brain show that resuscitation from TBI + HS with PNPH protects neocortical gray matter, including dendritic microstructure, and white matter axons and myelin. This neuroprotective effect persists with TBI alone, indicating brain-targeting benefits independent of blood pressure restoration.
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Affiliation(s)
- Jun Wang
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Yanrong Shi
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Suyi Cao
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Xiuyun Liu
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Lee J. Martin
- Department of Pathology, Johns Hopkins University, Baltimore, MD, United States
| | - Jan Simoni
- AntiRadical Therapeutics LLC, Sioux Falls, SD, United States
| | | | | | - Raymond C. Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, United States
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Ziółkowski A, Pudełko A, Kazimierska A, Uryga A, Czosnyka Z, Kasprowicz M, Czosnyka M. Peak appearance time in pulse waveforms of intracranial pressure and cerebral blood flow velocity. Front Physiol 2023; 13:1077966. [PMID: 36685171 PMCID: PMC9846027 DOI: 10.3389/fphys.2022.1077966] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Accepted: 12/08/2022] [Indexed: 01/05/2023] Open
Abstract
The shape of the pulse waveforms of intracranial pressure (ICP) and cerebral blood flow velocity (CBFV) typically contains three characteristic peaks. It was reported that alterations in cerebral hemodynamics may influence the shape of the pulse waveforms by changing peaks' configuration. However, the changes in peak appearance time (PAT) in ICP and CBFV pulses are only described superficially. We analyzed retrospectively ICP and CBFV signals recorded in traumatic brain injury patients during decrease in ICP induced by hypocapnia (n = 11) and rise in ICP during episodes of ICP plateau waves (n = 8). All three peaks were manually annotated in over 48 thousand individual pulses. The changes in PAT were compared between periods of vasoconstriction (expected during hypocapnia) and vasodilation (expected during ICP plateau waves) and their corresponding baselines. Correlation coefficient (rS) analysis between mean ICP and mean PATs was performed in each individual recording. Vasodilation prolonged PAT of the first peaks of ICP and CBFV pulses and the third peak of CBFV pulse. It also accelerated PAT of the third peak of ICP pulse. In contrast, vasoconstriction shortened appearance time of the first peaks of ICP and CBFV pulses and the second peak of ICP pulses. Analysis of individual recordings demonstrated positive association between changes in PAT of all three peaks in the CBFV pulse and mean ICP (rS range: 0.32-0.79 for significant correlations). Further study is needed to test whether PAT of the CBFV pulse may serve as an indicator of changes in ICP-this may open a perspective for non-invasive monitoring of alterations in mean ICP.
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Affiliation(s)
- Arkadiusz Ziółkowski
- Department of Biomedical Engineering, Faculty of Fundamental Problems of Technology, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Agata Pudełko
- Department of Biomedical Engineering, Faculty of Fundamental Problems of Technology, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Agnieszka Kazimierska
- Department of Biomedical Engineering, Faculty of Fundamental Problems of Technology, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Agnieszka Uryga
- Department of Biomedical Engineering, Faculty of Fundamental Problems of Technology, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Zofia Czosnyka
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Addenbrooke’s Hospital, University of Cambridge, Cambridge, United Kingdom
| | - Magdalena Kasprowicz
- Department of Biomedical Engineering, Faculty of Fundamental Problems of Technology, Wroclaw University of Science and Technology, Wroclaw, Poland,*Correspondence: Magdalena Kasprowicz,
| | - Marek Czosnyka
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Addenbrooke’s Hospital, University of Cambridge, Cambridge, United Kingdom,Institute of Electronic Systems, Faculty of Electronics and Information Technology, Warsaw University of Technology, Warsaw, Poland
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30
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Manquat E, Vallée F, Cartailler J. Risk of overestimating loss of cerebral autoregulation-author's reply. BJA OPEN 2022; 4:100094. [PMID: 37588790 PMCID: PMC10430805 DOI: 10.1016/j.bjao.2022.100094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 09/02/2022] [Indexed: 08/18/2023]
Affiliation(s)
- Elsa Manquat
- Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hopitaux de Paris, Paris, France
- AP-HP-Inria, Laboratoire Daniel Bernoulli, Paris, France
| | - Fabrice Vallée
- Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hopitaux de Paris, Paris, France
- Laboratoire de Mecanique des Solides (LMS), Ecole Polytechnique/CNRS/Institut Polytechnique de Paris, France
| | - Jerome Cartailler
- Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hopitaux de Paris, Paris, France
- INSERM, UMR-942, Paris, France
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31
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Jiang Y, Huang W, Wu XJ, Shi XL, Hu RR, Chen W, Zhang TF, Xu XL, Huang CG, Hou LJ. Invention of a non-invasive intracranial pressure (ICP) monitoring system - an enlightenment from a hydrocephalus study. Br J Neurosurg 2022; 36:693-698. [PMID: 35393907 DOI: 10.1080/02688697.2022.2059057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
BACKGROUND Mechanical obstruction is the most common cause of shunt failure for hydrocephalic patients. However, the diagnosis is extremely challenging and often requires invasive testing methods. Thus, a simple and non-invasive technique is in urgent need to predict the intracranial pressure (ICP) of hydrocephalic patients during their post-surgical follow-up, which could help neurosurgeons to determine the conditions of the shunt system. MATERIALS AND METHODS Two groups of patients were enrolled in the current study. In group I, patients were enrolled as they were diagnosed with high ICP hydrocephalus and received shunt surgery. The shunt valve pressures were taken for their post-surgical ICP. Meanwhile, the participants of group II exhibited abnormally increased lumbar puncture opening pressure (LPOP; from 180 to 400 mmH2O). Both the ICP and LPOP were used to match with their corresponding tympanic membrane temperature (TMT). RESULTS When patients' ICP were in the normal range (group I, from 50 to 180 mmH2O), the TMT correlated with ICP in a linear regression model (R2 = 0.59, p < 0.001). Interestingly, when patients exhibited above-normal ICP (LPOP was from 180 to 400 mmH2O), their TMT fit well with the ICP in a third-order polynomial regression (R2 = 0.88). When the ICP was 287.98 mmH2O, the TMT approached the vertex, which was 38.54 °C. Based on this TMT-ICP algorithm, we invented a non-invasive ICP monitor system. Interestingly, a tight linear correlation was detected between the ICP data drawn from the non-invasive device and Codman ICP monitoring system (R2 = 0.93, p < 0.01). CONCLUSIONS We believe the TMT-ICP algorithm (the Y-Jiang model) could be used for preliminary prediction of shunt malfunction as well as monitoring ICP changes.
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Affiliation(s)
- Ying Jiang
- Department of Neurosurgery, Shanghai Chang Zheng Hospital, Shanghai, People's Republic of China
| | - Wei Huang
- Department of Minimally Invasive Neurosurgery, The First affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
| | - Xiao-Jun Wu
- Department of Neurosurgery, Shanghai Cancer Center, Shanghai Fu-Dan University School of Medicine, Shanghai, People's Republic of China
| | - Xiao-Lei Shi
- Department of Radiology, Shanghai Chang Zheng Hospital, Shanghai, People's Republic of China
| | - Rong-Rong Hu
- Department of Radiology, Shanghai Chang Zheng Hospital, Shanghai, People's Republic of China
| | - Wen Chen
- Department of Neurosurgery, Shanghai Chang Zheng Hospital, Shanghai, People's Republic of China
| | - Teng-Fei Zhang
- Department of Neurosurgery, Shanghai Chang Zheng Hospital, Shanghai, People's Republic of China
| | - Xiao-Long Xu
- Department of Neurosurgery, Shanghai Chang Hai Hospital, Shanghai, People's Republic of China
| | - Cheng-Guang Huang
- Department of Neurosurgery, Shanghai Chang Zheng Hospital, Shanghai, People's Republic of China
| | - Li-Jun Hou
- Department of Neurosurgery, Shanghai Chang Zheng Hospital, Shanghai, People's Republic of China
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32
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Semenyutin V, Antonov V, Malykhina G, Salnikov V. Investigation of Cerebral Autoregulation Using Time-Frequency Transformations. Biomedicines 2022; 10:biomedicines10123057. [PMID: 36551813 PMCID: PMC9775421 DOI: 10.3390/biomedicines10123057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 10/24/2022] [Accepted: 11/20/2022] [Indexed: 11/29/2022] Open
Abstract
The authors carried out the study of the state of systemic and cerebral hemodynamics in normal conditions and in various neurosurgical pathologies using modern signal processing methods. The results characterize the condition for the mechanisms of cerebral circulation Institute of Computer Science and Control, Higher School of Cyber-Physical Systems and Control regulation, which allows for finding a solution to fundamental and specific clinical problems for the effective treatment of patients with various pathologies. The proposed method is based on the continuous wavelet transform of systemic arterial pressure and blood flow velocity signals in the middle cerebral artery recorded by non-invasive methods of photoplethysmography and transcranial doppler ultrasonography. The study of these signals in real-time in the frequency range of Mayer waves makes it possible to determine the cerebral autoregulation state in certain diseases before and after surgical interventions. The proposed method uses a cross-wavelet spectrum, which helps obtain wavelet coherence and a phase shift between the wavelet coefficients of systemic arterial pressure signals and blood flow velocity in the Mayer wave range. The obtained results enable comparing the proposed method with that based on the short-time Fourier transform. The comparison showed that the proposed method has higher sensitivity to changes in cerebral autoregulation and better localization of changes in time and frequency.
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Affiliation(s)
- Vladimir Semenyutin
- Almazov National Medical Research Center, Ministry of Health of Russia, Polenov Neurosurgical Research Institute, 12 Mayakovsky Street, Saint-Petersburg 191014, Russia
| | - Valery Antonov
- Department of Higher Mathematics, Peter the Great St. Petersburg Polytechnic University, Saint-Petersburg 195251, Russia
| | - Galina Malykhina
- Higher School of Cyber-Physical Systems and Control, Institute of Computer Science and Control, Peter the Great St. Petersburg Polytechnic University, Saint-Petersburg 195251, Russia
- Correspondence: ; Tel.: +8-921-43-15-114
| | - Vyacheslav Salnikov
- Higher School of Cyber-Physical Systems and Control, Institute of Computer Science and Control, Peter the Great St. Petersburg Polytechnic University, Saint-Petersburg 195251, Russia
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33
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Czosnyka M, Santarius T, Donnelly J, van den Dool REC, Sperna Weiland NH. Pro-Con Debate: The Clinical (Ir)relevance of the Lower Limit of Cerebral Autoregulation for Anesthesiologists. Anesth Analg 2022; 135:734-743. [DOI: 10.1213/ane.0000000000006123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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34
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Hawryluk GWJ, Citerio G, Hutchinson P, Kolias A, Meyfroidt G, Robba C, Stocchetti N, Chesnut R. Intracranial pressure: current perspectives on physiology and monitoring. Intensive Care Med 2022; 48:1471-1481. [PMID: 35816237 DOI: 10.1007/s00134-022-06786-y] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 06/08/2022] [Indexed: 02/06/2023]
Abstract
Intracranial pressure (ICP) monitoring is now viewed as integral to the clinical care of many life-threatening brain insults, such as severe traumatic brain injury, subarachnoid hemorrhage, and malignant stroke. It serves to warn of expanding intracranial mass lesions, to prevent or treat herniation events as well as pressure elevation which impedes nutrient delivery to the brain. It facilitates the calculation of cerebral perfusion pressure (CPP) and the estimation of cerebrovascular autoregulatory status. Despite advancements in our knowledge emanating from a half century of experience with this technology, important controversies remain related even to fundamental aspects of ICP measurements, including indications for monitoring, ICP treatment thresholds, and management of intracranial hypertension. Here, we review the history of ICP monitoring, the underlying pathophysiology as well as current perspectives on why, when and how ICP monitoring is best used. ICP is typically assessed invasively but a number of emerging, non-invasive technologies with inherently lower risk are showing promise. In selected cases, additional neuromonitoring can be used to assist in the interpretation of ICP monitoring information and adapt directed treatment accordingly. Additional efforts to expand the evidence base relevant to ICP monitoring, related technologies and management remain a high priority in neurosurgery and neurocritical care.
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Affiliation(s)
- Gregory W J Hawryluk
- Section of Neurosurgery, University of Manitoba, GB1, 820 Sherbrook Street, Winnipeg, MB, R3A 1R9, Canada.
| | - Giuseppe Citerio
- School of Medicine and Surgery, University of Milan-Bicocca, Milan, Italy.,Neuro-Intensive Care, Department of Neurosciences, San Gerardo Hospital, ASST-MONZA, Monza, Italy
| | - Peter Hutchinson
- Division of Neurosurgery, Department of Clinical Neurosciences, Addenbrooke's Hospital and University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB20QQ, UK
| | - Angelos Kolias
- Division of Neurosurgery, Department of Clinical Neurosciences, Addenbrooke's Hospital and University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB20QQ, UK
| | - Geert Meyfroidt
- Department and Laboratory of Intensive Care Medicine, University Hospitals Leuven and KU Leuven, Herestraat 49, Box 7003, 63 3000, Leuven, Belgium
| | - Chiara Robba
- Anaesthesia and Intensive Care, San Martino Research Hospital, Genoa, Italy
| | - Nino Stocchetti
- Anesthesia and Intensive Care, Department of Physiopathology and Transplantation, Milan University, Milan, Italy.,Department of Anaesthesia and Critical Care, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Randall Chesnut
- Neurosurgery, Neurotrauma, Department of Neurological Surgery, Department of Orthopaedic Surgery, School of Global Health, Harborview Medical Center, University of Washington, 325 Ninth Ave, Mailstop 359766, Seattle, WA, 98104-2499, USA
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35
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D'Andrea A, Fabiani D, Cante L, Caputo A, Sabatella F, Riegler L, Alfano G, Russo V. Transcranial Doppler ultrasound: Clinical applications from neurological to cardiological setting. JOURNAL OF CLINICAL ULTRASOUND : JCU 2022; 50:1212-1223. [PMID: 36218211 DOI: 10.1002/jcu.23344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 06/16/2023]
Abstract
Transcranial Doppler (TCD) ultrasonography is a rapid, noninvasive, real-time, and low-cost imaging technique. It is performed with a low-frequency (2 MHz) probe in order to evaluate the cerebral blood flow (CBF) and its pathological alterations, through specific acoustic windows. In the recent years, TCD use has been expanded across many clinical settings. Actually, the most widespread indication for TCD exam is represented by the diagnosis of paradoxical embolism, due to patent foramen ovale, in young patients with cryptogenic stroke. In addition, TCD has also found useful applications in neurological care setting, including the following: cerebral vasospasm following acute subarachnoid hemorrhage, brain trauma, cerebrovascular atherosclerosis, and evaluation of CBF and cerebral autoregulation after an ischemic stroke event. The present review aimed to describe the most recent evidences of TCD utilization from neurological to cardiological setting.
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Affiliation(s)
- Antonello D'Andrea
- Cardiology Unit, Umberto I Hospital, University of Campania "Luigi Vanvitelli", Nocera Inferiore, Italy
| | - Dario Fabiani
- Cardiology Unit, Department of Medical Translational Sciences, University of Campania "Luigi Vanvitelli"-Monaldi Hospital, Naples, Italy
| | - Luigi Cante
- Cardiology Unit, Department of Medical Translational Sciences, University of Campania "Luigi Vanvitelli"-Monaldi Hospital, Naples, Italy
| | - Adriano Caputo
- Cardiology Unit, Department of Medical Translational Sciences, University of Campania "Luigi Vanvitelli"-Monaldi Hospital, Naples, Italy
| | - Francesco Sabatella
- Cardiology Unit, Department of Medical Translational Sciences, University of Campania "Luigi Vanvitelli"-Monaldi Hospital, Naples, Italy
| | - Lucia Riegler
- Cardiology Unit, Umberto I Hospital, University of Campania "Luigi Vanvitelli", Nocera Inferiore, Italy
| | - Gabriele Alfano
- Cardiology Unit, Umberto I Hospital, University of Campania "Luigi Vanvitelli", Nocera Inferiore, Italy
| | - Vincenzo Russo
- Cardiology Unit, Department of Medical Translational Sciences, University of Campania "Luigi Vanvitelli"-Monaldi Hospital, Naples, Italy
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Owen B, Vangala A, Fritch C, Alsarah AA, Jones T, Davis H, Shuttleworth CW, Carlson AP. Cerebral Autoregulation Correlation With Outcomes and Spreading Depolarization in Aneurysmal Subarachnoid Hemorrhage. Stroke 2022; 53:1975-1983. [PMID: 35196873 PMCID: PMC9133018 DOI: 10.1161/strokeaha.121.037184] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Delayed cerebral ischemia remains one of the principal therapeutic targets after aneurysmal subarachnoid hemorrhage. While large vessel vasospasm may contribute to ischemia, increasing evidence suggests that physiological impairment through disrupted impaired cerebral autoregulation (CA) and spreading depolarizations (SDs) also contribute to delayed cerebral ischemia and poor neurological outcome. This study seeks to explore the intermeasure correlation of different measures of CA, as well as correlation with SD and neurological outcome. METHODS Simultaneous measurement of 7 continuous indices of CA was calculated in 19 subjects entered in a prospective study of SD in aneurysmal subarachnoid hemorrhage undergoing surgical aneurysm clipping. Intermeasure agreement was assessed, and the association of each index with modified Rankin Scale score at 90 days and occurrence of SD was assessed. RESULTS There were 4102 hours of total monitoring time across the 19 subjects. In time-resolved assessment, no CA measures demonstrated significant correlation; however, most demonstrate significant correlation averaged over 1 hour. Pressure reactivity (PRx), oxygen reactivity, and oxygen saturation reactivity were significantly correlated with modified Rankin Scale score at 90 days. PRx and oxygen reactivity also were correlated with the occurrence of SD events. Across multiple CA measure reactivity indices, a threshold between 0.3 and 0.5 was most associated with intervals containing SD. CONCLUSIONS Different continuous CA indices do not correlate well with each other on a highly time-resolved basis, so should not be viewed as interchangeable. PRx and oxygen reactivity are the most reliable indices in identifying risk of worse outcome in patients with aneurysmal subarachnoid hemorrhage undergoing surgical treatment. SD occurrence is correlated with impaired CA across multiple CA measurement techniques and may represent the pathological mechanism of delayed cerebral ischemia in patients with impaired CA. Optimization of CA in patients with aneurysmal subarachnoid hemorrhage may lead to decreased incidence of SD and improved neurological outcomes. Future studies are needed to evaluate these hypotheses and approaches.
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Affiliation(s)
- Bryce Owen
- University of New Mexico, School of Medicine
| | - Adarsh Vangala
- University of Arizona College of Medicine, Department of Internal Medicine
| | - Chanju Fritch
- Penn State School of Medicine, Department of Neurosurgery
| | - Ali A. Alsarah
- University of New Mexico School of Medicine, Department of Neurology
| | - Tom Jones
- University of New Mexico School of Medicine, Department of Psychiatry
| | - Herbert Davis
- University of New Mexico School of Medicine, Department of Internal Medicine, Division of Epidemiology, Biostatistics, and Preventive Medicine
| | | | - Andrew P. Carlson
- University of New Mexico School of Medicine, Department of Neurosurgery
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Rivera Lara L, Genevieve Hirsch K. Moving towards precision medicine in post-cardiac arrest care: Using cerebrovascular autoregulation to individualize blood pressure. Resuscitation 2022; 175:48-49. [DOI: 10.1016/j.resuscitation.2022.03.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 03/30/2022] [Indexed: 11/30/2022]
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38
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Nogueira RC, Aries M, Minhas JS, H Petersen N, Xiong L, Kainerstorfer JM, Castro P. Review of studies on dynamic cerebral autoregulation in the acute phase of stroke and the relationship with clinical outcome. J Cereb Blood Flow Metab 2022; 42:430-453. [PMID: 34515547 PMCID: PMC8985432 DOI: 10.1177/0271678x211045222] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Acute stroke is associated with high morbidity and mortality. In the last decades, new therapies have been investigated with the aim of improving clinical outcomes in the acute phase post stroke onset. However, despite such advances, a large number of patients do not demonstrate improvement, furthermore, some unfortunately deteriorate. Thus, there is a need for additional treatments targeted to the individual patient. A potential therapeutic target is interventions to optimize cerebral perfusion guided by cerebral hemodynamic parameters such as dynamic cerebral autoregulation (dCA). This narrative led to the development of the INFOMATAS (Identifying New targets FOr Management And Therapy in Acute Stroke) project, designed to foster interventions directed towards understanding and improving hemodynamic aspects of the cerebral circulation in acute cerebrovascular disease states. This comprehensive review aims to summarize relevant studies on assessing dCA in patients suffering acute ischemic stroke, intracerebral haemorrhage, and subarachnoid haemorrhage. The review will provide to the reader the most consistent findings, the inconsistent findings which still need to be explored further and discuss the main limitations of these studies. This will allow for the creation of a research agenda for the use of bedside dCA information for prognostication and targeted perfusion interventions.
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Affiliation(s)
- Ricardo C Nogueira
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil.,Department of Neurology, Hospital Nove de Julho, São Paulo, Brazil
| | - Marcel Aries
- Department of Intensive Care, University of Maastricht, Maastricht University Medical Center+, School for Mental Health and Neuroscience (MHeNS), Maastricht, The Netherlands
| | - Jatinder S Minhas
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, NIHR Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - Nils H Petersen
- Department of Neurology, Yale University School of Medicine, New Haven, USA
| | - Li Xiong
- Department of Medicine & Therapeutics, The Chinese University of Hong Kong, Hong Kong, China
| | - Jana M Kainerstorfer
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, USA.,Neuroscience Institute, Carnegie Mellon University, Pittsburgh, USA
| | - Pedro Castro
- Department of Neurology, Faculty of Medicine of University of Porto, Centro Hospitalar Universitário de São João, Porto, Portugal
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Alkhachroum A, Kromm J, De Georgia MA. Big data and predictive analytics in neurocritical care. Curr Neurol Neurosci Rep 2022; 22:19-32. [PMID: 35080751 DOI: 10.1007/s11910-022-01167-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/15/2021] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW To describe predictive data and workflow in the intensive care unit when managing neurologically ill patients. RECENT FINDINGS In the era of Big Data in medicine, intensive critical care units are data-rich environments. Neurocritical care adds another layer of data with advanced multimodal monitoring to prevent secondary brain injury from ischemia, tissue hypoxia, and a cascade of ongoing metabolic events. A step closer toward personalized medicine is the application of multimodal monitoring of cerebral hemodynamics, bran oxygenation, brain metabolism, and electrophysiologic indices, all of which have complex and dynamic interactions. These data are acquired and visualized using different tools and monitors facing multiple challenges toward the goal of the optimal decision support system. In this review, we highlight some of the predictive data used to diagnose, treat, and prognosticate the neurologically ill patients. We describe information management in neurocritical care units including data acquisition, wrangling, analysis, and visualization.
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Affiliation(s)
- Ayham Alkhachroum
- Miller School of Medicine, Neurocritical Care Division, Department of Neurology, University of Miami, Miami, FL, 33146, USA
| | - Julie Kromm
- Cumming School of Medicine, Department of Critical Care Medicine, University of Calgary, Calgary, AB, Canada
- Cumming School of Medicine, Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Michael A De Georgia
- Center for Neurocritical Care, Neurological Institute, University Hospital Cleveland Medical Center, 11100 Euclid Avenue, Cleveland, OH, 44106-5040, USA.
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40
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Oshorov A, Savin I, Alexandrova E, Bragin D. Assessment of Optimal Arterial Pressure with Near-Infrared Spectroscopy in Traumatic Brain Injury Patients. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1395:133-137. [PMID: 36527627 PMCID: PMC10066817 DOI: 10.1007/978-3-031-14190-4_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In patients with severe traumatic brain injury (TBI), simultaneous measurement of intracranial and arterial blood pressure (ICP and ABP, respectively) allows monitoring of cerebral perfusion pressure (CPP) and the assessment of cerebral autoregulation (CA). CPP, a difference between ICP and ABP, is the pressure gradient that drives oxygen delivery to cerebral tissue. CA is the ability of cerebral vasculature to maintain stable blood flow despite changes in CPP and thus, is an important homeostatic mechanism. Pressure reactivity index (PRx), a moving Pearson's correlation between slow waves in ICP and ABP, has been most frequently cited in literature over the past two decades as a tool for CA evaluation. However, in some clinical situations, ICP monitoring may be unavailable or contraindicated. In such cases, simultaneous mean arterial pressure (MAP) monitoring and near-infrared spectroscopy (NIRS) can be used for CA assessment by cerebral oximetry index (COx), allowing calculation of the optimal blood pressure (MAPOPT). The purpose of this study was to compare regional oxygen saturation (rSO2)-based CA (COx) with ICP/ABP-based CA (PRx) in TBI patients and to compare MAPOPT derived from both technologies. Three TBI patients were monitored at the bedside to measure CA using both PRx and COx. Patients were monitored daily for up to 3 days from TBI. Averaged PRx and COx-, and PRx and COx-based MAPOPT were compared using Pearson's correlation. Bias analysis was performed between these same CA metrics. Correlation between averaged values of COx and PRx was R = 0.35, p = 0.15. Correlation between optimal MAP calculated for COx and PRx was R = 0.49, p < 0.038. Bland-Altman analysis showed moderate agreement with a bias of 0.16 ± 0.23 for COx versus PRx and good agreement with a bias of 0.39 ± 7.89 for optimal MAP determined by COx versus PRx. Non-invasive measurement of CA by NIRS (COx) is not correlated with invasive ICP/ABP-based CA (PRx). However, the determination of MAPOPT using COx is correlated with MAPOPT derived from PRx. Obtained results demonstrate that COx is not an acceptable substitute for PRx in TBI patients. However, in some TBI cases, NIRS may be useful in determining MAP determination.
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Affiliation(s)
- Andrey Oshorov
- Department of Neurosurgical Intensive Care, Burdenko Neurosurgery Institute, Moscow, Russia.
| | - I Savin
- Department of Neurosurgical Intensive Care, Burdenko Neurosurgery Institute, Moscow, Russia
| | - E Alexandrova
- Department of Neurosurgical Intensive Care, Burdenko Neurosurgery Institute, Moscow, Russia
| | - D Bragin
- Lovelace Biomedical Research Institute, Albuquerque, NM, USA
- Department of Neurology, University of New Mexico School of Medicine, Albuquerque, NM, USA
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41
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Effects of circulatory arrest and cardiopulmonary bypass on cerebral autoregulation in neonatal swine. Pediatr Res 2022; 91:1374-1382. [PMID: 33947997 PMCID: PMC8566324 DOI: 10.1038/s41390-021-01525-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 02/02/2021] [Accepted: 03/18/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND Cerebral autoregulation mechanisms help maintain adequate cerebral blood flow (CBF) despite changes in cerebral perfusion pressure. Impairment of cerebral autoregulation, during and after cardiopulmonary bypass (CPB), may increase risk of neurologic injury in neonates undergoing surgery. In this study, alterations of cerebral autoregulation were assessed in a neonatal swine model probing four perfusion strategies. METHODS Neonatal swine (n = 25) were randomized to continuous deep hypothermic cardiopulmonary bypass (DH-CPB, n = 7), deep hypothermic circulatory arrest (DHCA, n = 7), selective cerebral perfusion (SCP, n = 7) at deep hypothermia, or normothermic cardiopulmonary bypass (control, n = 4). The correlation coefficient (LDx) between laser Doppler measurements of CBF and mean arterial blood pressure was computed at initiation and conclusion of CPB. Alterations in cerebral autoregulation were assessed by the change between initial and final LDx measurements. RESULTS Cerebral autoregulation became more impaired (LDx increased) in piglets that underwent DH-CPB (initial LDx: median 0.15, IQR [0.03, 0.26]; final: 0.45, [0.27, 0.74]; p = 0.02). LDx was not altered in those undergoing DHCA (p > 0.99) or SCP (p = 0.13). These differences were not explained by other risk factors. CONCLUSIONS In a validated swine model of cardiac surgery, DH-CPB had a significant effect on cerebral autoregulation, whereas DHCA and SCP did not. IMPACT Approximately half of the patients who survive neonatal heart surgery with cardiopulmonary bypass (CPB) experience neurodevelopmental delays. This preclinical investigation takes steps to elucidate and isolate potential perioperative risk factors of neurologic injury, such as impairment of cerebral autoregulation, associated with cardiac surgical procedures involving CPB. We demonstrate a method to characterize cerebral autoregulation during CPB pump flow changes in a neonatal swine model of cardiac surgery. Cerebral autoregulation was not altered in piglets that underwent deep hypothermic circulatory arrest (DHCA) or selective cerebral perfusion (SCP), but it was altered in piglets that underwent deep hypothermic CBP.
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“Technical considerations on the use of Granger causality in neuromonitoring“. BRAIN MULTIPHYSICS 2022. [DOI: 10.1016/j.brain.2022.100044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Zipfel J, Engel J, Hockel K, Heimberg E, Schuhmann MU, Neunhoeffer F. Effects of hypertonic saline on intracranial pressure and cerebral autoregulation in pediatric traumatic brain injury. J Neurosurg Pediatr 2021; 28:631-637. [PMID: 34560657 DOI: 10.3171/2021.6.peds21143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 06/07/2021] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Hypertonic saline (HTS) is commonly used in children to lower intracranial pressure (ICP) after severe traumatic brain injury (sTBI). While ICP and cerebral perfusion pressure (CPP) correlate moderately to TBI outcome, indices of cerebrovascular autoregulation enhance the correlation of neuromonitoring data to neurological outcome. In this study, the authors sought to investigate the effect of HTS administration on ICP, CPP, and autoregulation in pediatric patients with sTBI. METHODS Twenty-eight pediatric patients with sTBI who were intubated and sedated were included. Blood pressure and ICP were actively managed according to the autoregulation index PRx (pressure relativity index to determine and maintain an optimal CPP [CPPopt]). In cases in which ICP was continuously > 20 mm Hg despite all other measures to decrease it, an infusion of 3% HTS was administered. The monitoring data of the first 6 hours after HTS administration were analyzed. The Glasgow Outcome Scale (GOS) score at the 3-month follow-up was used as the primary outcome measure, and patients were dichotomized into favorable (GOS score 4 or 5) and unfavorable (GOS score 1-3) groups. RESULTS The mean dose of HTS was 40 ml 3% NaCl. No significant difference in ICP and PRx was seen between groups at the HTS administration. ICP was lowered significantly in all children, with the effect lasting as long as 6 hours. The lowering of ICP was significantly greater and longer in children with a favorable outcome (p < 0.001); only this group showed significant improvement of autoregulatory capacity (p = 0.048). A newly established HTS response index clearly separated the outcome groups. CONCLUSIONS HTS significantly lowered ICP in all children after sTBI. This effect was significantly greater and longer-lasting in children with a favorable outcome. Moreover, HTS administration restored disturbed autoregulation only in the favorable outcome group. This highlights the role of a "rescuable" autoregulation regarding outcome, which might be a possible indicator of injury severity. The effect of HTS on autoregulation and other possible mechanisms should be further investigated.
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Affiliation(s)
- Julian Zipfel
- 1Department of Neurosurgery, Division of Pediatric Neurosurgery, University of Tuebingen, Tuebingen
| | - Juliane Engel
- 2Pediatric Intensive Care Unit, University Children's Hospital of Tuebingen, Tuebingen; and
| | | | - Ellen Heimberg
- 2Pediatric Intensive Care Unit, University Children's Hospital of Tuebingen, Tuebingen; and
| | - Martin U Schuhmann
- 1Department of Neurosurgery, Division of Pediatric Neurosurgery, University of Tuebingen, Tuebingen
| | - Felix Neunhoeffer
- 2Pediatric Intensive Care Unit, University Children's Hospital of Tuebingen, Tuebingen; and
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Role of Transcranial Doppler in Cardiac Surgery Patients. CURRENT ANESTHESIOLOGY REPORTS 2021. [DOI: 10.1007/s40140-021-00483-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Abstract
Purpose of Review
This review discusses applications of transcranial Doppler (TCD) in cardiac surgery, its efficacy in preventing adverse events such as postoperative cognitive decline and stroke, and its impact on clinical outcomes in these patients.
Recent Findings
TCD alone and in combination with other neuromonitoring modalities has attracted attention as a potential monitoring tool in cardiac surgery patients. TCD allows not only the detection of microemboli and measurement of cerebral blood flow velocity in cerebral arteries but also the assessment of cerebral autoregulation.
Summary
Neuromonitoring is critically important in cardiac surgery as surgical and anesthetic interventions as well as several other factors may increase the risk of cerebral embolization (gaseous and particulate) and cerebral perfusion anomalies, which may lead to adverse neurological events. As an experimental tool, TCD has revealed a possible association of poor neurological outcome with intraoperative cerebral emboli and impaired cerebral perfusion. However, to date, there is no evidence that routine use of transcranial Doppler can improve neurological outcome after cardiac surgery.
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Claassen JAHR, Thijssen DHJ, Panerai RB, Faraci FM. Regulation of cerebral blood flow in humans: physiology and clinical implications of autoregulation. Physiol Rev 2021; 101:1487-1559. [PMID: 33769101 PMCID: PMC8576366 DOI: 10.1152/physrev.00022.2020] [Citation(s) in RCA: 304] [Impact Index Per Article: 101.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Brain function critically depends on a close matching between metabolic demands, appropriate delivery of oxygen and nutrients, and removal of cellular waste. This matching requires continuous regulation of cerebral blood flow (CBF), which can be categorized into four broad topics: 1) autoregulation, which describes the response of the cerebrovasculature to changes in perfusion pressure; 2) vascular reactivity to vasoactive stimuli [including carbon dioxide (CO2)]; 3) neurovascular coupling (NVC), i.e., the CBF response to local changes in neural activity (often standardized cognitive stimuli in humans); and 4) endothelium-dependent responses. This review focuses primarily on autoregulation and its clinical implications. To place autoregulation in a more precise context, and to better understand integrated approaches in the cerebral circulation, we also briefly address reactivity to CO2 and NVC. In addition to our focus on effects of perfusion pressure (or blood pressure), we describe the impact of select stimuli on regulation of CBF (i.e., arterial blood gases, cerebral metabolism, neural mechanisms, and specific vascular cells), the interrelationships between these stimuli, and implications for regulation of CBF at the level of large arteries and the microcirculation. We review clinical implications of autoregulation in aging, hypertension, stroke, mild cognitive impairment, anesthesia, and dementias. Finally, we discuss autoregulation in the context of common daily physiological challenges, including changes in posture (e.g., orthostatic hypotension, syncope) and physical activity.
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Affiliation(s)
- Jurgen A H R Claassen
- Department of Geriatrics, Radboud University Medical Center, Donders Institute for Brain, Cognition, and Behaviour, Nijmegen, The Netherlands
| | - Dick H J Thijssen
- Department of Physiology, Radboud Institute for Health Sciences, Nijmegen, The Netherlands
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Ronney B Panerai
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
- >National Institute for Health Research Leicester Biomedical Research Centre, University of Leicester, Leicester, United Kingdom
| | - Frank M Faraci
- Departments of Internal Medicine, Neuroscience, and Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa
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Panerai RB, Haunton VJ, Llwyd O, Minhas JS, Katsogridakis E, Salinet ASM, Maggio P, Robinson TG. Cerebral critical closing pressure and resistance-area product: the influence of dynamic cerebral autoregulation, age and sex. J Cereb Blood Flow Metab 2021; 41:2456-2469. [PMID: 33818187 PMCID: PMC8392773 DOI: 10.1177/0271678x211004131] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 01/19/2021] [Accepted: 02/16/2021] [Indexed: 11/21/2022]
Abstract
Instantaneous arterial pressure-flow (or velocity) relationships indicate the existence of a cerebral critical closing pressure (CrCP), with the slope of the relationship expressed by the resistance-area product (RAP). In 194 healthy subjects (20-82 years, 90 female), cerebral blood flow velocity (CBFV, transcranial Doppler), arterial blood pressure (BP, Finapres) and end-tidal CO2 (EtCO2, capnography) were measured continuously for five minutes during spontaneous fluctuations of BP at rest. The dynamic cerebral autoregulation (CA) index (ARI) was extracted with transfer function analysis from the CBFV step response to the BP input and step responses were also obtained for the BP-CrCP and BP-RAP relationships. ARI was shown to decrease with age at a rate of -0.025 units/year in men (p = 0.022), but not in women (p = 0.40). The temporal patterns of the BP-CBFV, BP-CrCP and BP-RAP step responses were strongly influenced by the ARI (p < 0.0001), but not by sex. Age was also a significant determinant of the peak of the CBFV step response and the tail of the RAP response. Whilst the RAP step response pattern is consistent with a myogenic mechanism controlling dynamic CA, further work is needed to explore the potential association of the CrCP step response with the flow-mediated component of autoregulation.
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Affiliation(s)
- Ronney B Panerai
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
| | - Victoria J Haunton
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
| | - Osian Llwyd
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Jatinder S Minhas
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
| | - Emmanuel Katsogridakis
- Department of Vascular Surgery, Wythenshawe Hospital, Manchester Foundation Trust, Manchester, UK
| | - Angela SM Salinet
- Neurology Department, Hospital das Clinicas, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil
| | - Paola Maggio
- Neurology Department, ASST Bergamo EST (BG), Italy
| | - Thompson G Robinson
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
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Lewis C, Levine A, Balmert LC, Chen L, Sherwani SS, Nemeth AJ, Grafman J, Gottesman R, Brown CH, Hogue CW. Neurocognitive, Quality of Life, and Behavioral Outcomes for Patients With Covert Stroke After Cardiac Surgery: Exploratory Analysis of Data From a Prospectively Randomized Trial. Anesth Analg 2021; 133:1187-1196. [PMID: 34319914 PMCID: PMC8542565 DOI: 10.1213/ane.0000000000005690] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Asymptomatic brain ischemic injury detected with diffusion-weighted magnetic resonance imaging (DWI) is reported in more than one-half of patients after cardiac surgery. There are conflicting findings on whether DWI-detected covert stroke is associated with neurocognitive dysfunction after surgery, and it is unclear whether such ischemic injury affects quality of life or behavioral outcomes. The purpose of this study was to perform exploratory analysis on whether covert stroke after cardiac surgery is associated with delayed neurocognitive recovery 1 month after surgery, impaired quality of life, anxiety, or depression. METHODS Analysis of data collected in a prospectively randomized study in patients undergoing cardiac surgery testing whether basing mean arterial pressure (MAP) targets during cardiopulmonary bypass to be above the lower limit of cerebral autoregulation versus usual practices reduces the frequency of adverse neurological outcomes. A neuropsychological testing battery was administered before surgery and then 1 month later. Patients underwent brain magnetic resonance imaging (MRI) between postoperative days 3 and 5. The primary outcome was DWI-detected ischemic lesion; the primary end point was change from baseline in domain-specific neurocognitive Z scores 1 month after surgery. Secondary outcomes included a composite indicator of delayed neurocognitive recovery, quality of life measures, state and trait anxiety, and Beck Depression Inventory scores. RESULTS Of the 164 patients with postoperative MRI data, clinical stroke occurred in 10 patients. Of the remaining 154 patients, 85 (55.2%) had a covert stroke. There were no statistically significant differences for patients with or without covert stroke in the change from baseline in Z scores in any of the cognitive domains tested adjusted for sex, baseline cognitive score, and randomization treatment arm. The frequency of delayed neurocognitive recovery (no covert stroke, 15.1%; covert stroke, 17.6%; P = .392), self-reported quality of life measurements, anxiety rating, or depression scores were not different between those with or without DWI ischemic injury. CONCLUSIONS More than one-half of patients undergoing cardiac surgery demonstrated covert stroke. In this exploratory analysis, covert stroke was not found to be significantly associated with neurocognitive dysfunction 1 month after surgery; evidence of impaired quality of life, anxiety, or depression, albeit a type II error, cannot be excluded.
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Affiliation(s)
| | | | | | - Liqi Chen
- Division of Biostatistics, Department of Preventive Medicine
| | | | | | - Jordan Grafman
- Shirley Ryan Abilitylab and the Department of Rehabilitation and Physical Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | | | - Charles H Brown
- Department of Anesthesiology & Critical Care, The Johns Hopkins University School of Medicine, Baltimore, Maryland
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Milne B, Gilbey T, Gautel L, Kunst G. Neuromonitoring and Neurocognitive Outcomes in Cardiac Surgery: A Narrative Review. J Cardiothorac Vasc Anesth 2021; 36:2098-2113. [PMID: 34420812 DOI: 10.1053/j.jvca.2021.07.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 06/28/2021] [Accepted: 07/15/2021] [Indexed: 12/30/2022]
Abstract
Neurocognitive dysfunction after cardiac surgery can present with diverse clinical phenotypes, which include postoperative delirium, postoperative cognitive dysfunction, and stroke, and it presents a significant healthcare burden for both patients and providers. Neurologic monitoring during cardiac surgery includes several modalities assessing cerebral perfusion and oxygenation (near-infrared spectroscopy, transcranial Doppler and jugular venous bulb saturation monitoring) and those that measure cerebral function (processed and unprocessed electroencephalogram), reflecting an absence of a single, definitive neuromonitor. This narrative review briefly describes the technologic basis of these neuromonitoring modalities, before exploring their use in clinical practice, both as tools to predict neurocognitive dysfunction, and with a bundle of interventions designed to optimize cerebral oxygen supply, with the aim of reducing postoperative delirium and cognitive dysfunction following cardiac surgery.
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Affiliation(s)
- Benjamin Milne
- Department of Anaesthetics and Pain Medicine, King's College Hospital NHS Foundation Trust, London, UK
| | - Thomas Gilbey
- Department of Anaesthetics and Pain Medicine, King's College Hospital NHS Foundation Trust, London, UK
| | - Livia Gautel
- Department of Anaesthetics and Pain Medicine, King's College Hospital NHS Foundation Trust, London, UK; School of Biological Sciences in Edinburgh, University of Edinburgh, Edinburgh, UK; School of Cardiovascular Medicine & Sciences, King's College London British Heart Foundation Centre of Excellence, London, UK
| | - Gudrun Kunst
- Department of Anaesthetics and Pain Medicine, King's College Hospital NHS Foundation Trust, London, UK; School of Cardiovascular Medicine & Sciences, King's College London British Heart Foundation Centre of Excellence, London, UK.
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Tsaousi G, Tramontana A, Yamani F, Bilotta F. Cerebral Perfusion and Brain Oxygen Saturation Monitoring with: Jugular Venous Oxygen Saturation, Cerebral Oximetry, and Transcranial Doppler Ultrasonography. Anesthesiol Clin 2021; 39:507-523. [PMID: 34392882 DOI: 10.1016/j.anclin.2021.03.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Accumulating evidence indicates that cerebral desaturation in the perioperative period occurs more frequently than recognized. Combining monitoring modalities that reflect different aspects of cerebral perfusion status, such as near-infrared spectroscopy, jugular bulb saturation, and transcranial Doppler ultrasonography, may provide an extended window for prevention, early detection, and prompt intervention in ongoing hypoxic/ischemic neuronal injury and, thereby, improve neurologic outcome. Such an approach would minimize the impact of limitations of each monitoring modality, while individual components complement each other, enhancing the accuracy of acquired information. Current literature has failed to demonstrate any clear-cut clinical benefit of these modalities on outcome prognosis.
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Affiliation(s)
- Georgia Tsaousi
- Department of Anesthesiology and ICU, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, University Campus, 54124 Thessaloniki, Greece
| | - Alessio Tramontana
- Department of Anesthesiology, Critical Care and Pain Medicine, Policlinico Umberto I, "Sapienza" University of Rome, viale del Policlinico 151, 00185 Rome, Italy
| | - Farouk Yamani
- Department of Anesthesiology, Critical Care and Pain Medicine, Policlinico Umberto I, "Sapienza" University of Rome, viale del Policlinico 151, 00185 Rome, Italy
| | - Federico Bilotta
- Department of Anesthesiology, Critical Care and Pain Medicine, Policlinico Umberto I, "Sapienza" University of Rome, viale del Policlinico 151, 00185 Rome, Italy.
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Ali J, Cody J, Maldonado Y, Ramakrishna H. Near-Infrared Spectroscopy (NIRS) for Cerebral and Tissue Oximetry: Analysis of Evolving Applications. J Cardiothorac Vasc Anesth 2021; 36:2758-2766. [PMID: 34362641 DOI: 10.1053/j.jvca.2021.07.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 11/11/2022]
Abstract
THE USE OF NEAR-INFRARED SPECTROSCOPY (NIRS) has increased significantly worldwide in the past decade. This technology, first described more than 40 years ago, is based on the fact that near-infrared light is able to penetrate biologic tissue and can obtain real-time, noninvasive information on tissue oxygenation and metabolism. In the clinical setting, NIRS has been able to provide clinicians potentially valuable information in patients with impaired microcirculations (systemic and cerebral). Near-infrared spectroscopy has progressed beyond assessment of brain oxygenation to monitor local tissue and muscle oxygenation and perfusion. This review analyzes the published data and provides the clinician a comprehensive account of the perioperative utility of NIRS in cardiac, vascular and thoracic surgery, as well as its increasing role in tissue/muscle oxygenation monitoring.
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Affiliation(s)
- Jafer Ali
- Department of Cardiothoracic Anesthesiology, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH
| | - Joseph Cody
- Division of Cardiothoracic Anesthesiology, Department of Anesthesiology, The Ohio State Wexner Medical Center, Columbus, OH
| | - Yasdet Maldonado
- Department of Cardiothoracic Anesthesiology, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH
| | - Harish Ramakrishna
- Division of Cardiovascular and Thoracic Anesthesiology, Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN.
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