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Lu S, Di John Portela I, Martino N, Bossardi Ramos R, Salinero AE, Smith RM, Zuloaga KL, Adam AP. A transient brain endothelial translatome response to endotoxin is associated with mild cognitive changes post-shock in young mice. Neuroscience 2024; 555:194-204. [PMID: 39067684 PMCID: PMC11470799 DOI: 10.1016/j.neuroscience.2024.07.041] [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: 05/16/2024] [Revised: 07/10/2024] [Accepted: 07/23/2024] [Indexed: 07/30/2024]
Abstract
Sepsis-associated encephalopathy (SAE) is associated with increased risk of long-term cognitive impairment. SAE is driven, at least in part, by brain endothelial dysfunction in response to systemic cytokine signaling. However, the mechanisms driving SAE and its consequences remain largely unknown. Here, we performed translating ribosome affinity purification and RNA-sequencing (TRAP-seq) from the brain endothelium to determine the transcriptional changes after an acute endotoxemic (LPS) challenge. LPS induced a strong acute transcriptional response in the brain endothelium that partially correlates with the whole brain transcriptional response and suggested an endothelial-specific hypoxia response. Consistent with a crucial role for IL-6, loss of the main regulator of this pathway, SOCS3, leads to a broadening of the population of genes responsive to LPS, suggesting that an overactivation of the IL-6/JAK/STAT3 pathway leads to an increased transcriptional response that could explain our prior findings of severe brain injury in these mice. To identify any potential sequelae of this acute response, we performed brain TRAP-seq following a battery of behavioral tests in mice after apparent recovery. We found that the transcriptional response returns to baseline within days post-challenge, but reductions in gene expression regulating protein translation and respiratory electron transport remained. We observed that mice that recovered from the endotoxemic shock showed mild, sex-dependent cognitive impairment, suggesting that the acute brain injury led to sustained effects. A better understanding of the transcriptional and non-transcriptional changes in response to shock is needed in order to prevent and/or revert the devastating consequences of septic shock.
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Affiliation(s)
- Shuhan Lu
- Department of Molecular and Cellular Physiology, Albany Medical College, United States
| | - Iria Di John Portela
- Department of Molecular and Cellular Physiology, Albany Medical College, United States
| | - Nina Martino
- Department of Molecular and Cellular Physiology, Albany Medical College, United States
| | - Ramon Bossardi Ramos
- Department of Molecular and Cellular Physiology, Albany Medical College, United States
| | - Abigail E Salinero
- Department of Neuroscience & Experimental Therapeutics, Albany Medical College, United States
| | - Rachel M Smith
- Department of Neuroscience & Experimental Therapeutics, Albany Medical College, United States
| | - Kristen L Zuloaga
- Department of Neuroscience & Experimental Therapeutics, Albany Medical College, United States
| | - Alejandro P Adam
- Department of Molecular and Cellular Physiology, Albany Medical College, United States; Department of Ophthalmology, Albany Medical College, United States.
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2
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Olsen MH, Riberholt C, Capion T, Plovsing RR, Møller K, Berg RMG. Test-retest reliability of transfer function analysis metrics for assessing dynamic cerebral autoregulation to spontaneous blood pressure oscillations. Exp Physiol 2024; 109:1024-1039. [PMID: 38590228 PMCID: PMC11215465 DOI: 10.1113/ep091500] [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: 08/28/2023] [Accepted: 03/18/2024] [Indexed: 04/10/2024]
Abstract
Transfer function analysis (TFA) is a widely used method for assessing dynamic cerebral autoregulation in humans. In the present study, we assessed the test-retest reliability of established TFA metrics derived from spontaneous blood pressure oscillations and based on 5 min recordings. The TFA-based gain, phase and coherence in the low-frequency range (0.07-0.20 Hz) from 19 healthy volunteers, 37 patients with subarachnoid haemorrhage and 19 patients with sepsis were included. Reliability assessments included the smallest real difference (SRD) and the coefficient of variance for comparing consecutive 5 min recordings, temporally separated 5 min recordings and consecutive recordings with a minimal length of 10 min. In healthy volunteers, temporally separating the 5 min recordings led to a 0.38 (0.01-0.79) cm s-1 mmHg-1 higher SRD for gain (P = 0.032), and extending the duration of recordings did not affect the reliability. In subarachnoid haemorrhage, temporal separation led to a 0.85 (-0.13 to 1.93) cm s-1 mmHg-1 higher SRD (P = 0.047) and a 20 (-2 to 41)% higher coefficient of variance (P = 0.038) for gain, but neither metric was affected by extending the recording duration. In sepsis, temporal separation increased the SRD for phase by 94 (23-160)° (P = 0.006) but was unaffected by extending the recording. A recording duration of 8 min was required to achieve stable gain and normalized gain measures in healthy individuals, and even longer recordings were required in patients. In conclusion, a recording duration of 5 min appears insufficient for obtaining stable and reliable TFA metrics when based on spontaneous blood pressure oscillations, particularly in critically ill patients with subarachnoid haemorrhage and sepsis.
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Affiliation(s)
- Markus Harboe Olsen
- Department of Neuroanaesthesiology, The Neuroscience CentreCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
| | - Christian Riberholt
- Department of Neuroanaesthesiology, The Neuroscience CentreCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
- Department of Neurorehabilitation/Traumatic Brain Injury Unit, The Neuroscience CentreCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
| | - Tenna Capion
- Department of Neurosurgery, The Neuroscience CentreCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
| | - Ronni R. Plovsing
- Department of Anaesthesia and Intensive CareCopenhagen University Hospital – HvidovreCopenhagenDenmark
- Department of Clinical Medicine, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Kirsten Møller
- Department of Neuroanaesthesiology, The Neuroscience CentreCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
- Department of Clinical Medicine, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Ronan M. G. Berg
- Department of Clinical Physiology and Nuclear Medicine, The Diagnostic CentreCopenhagen 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
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3
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Windoloski KA, Janum S, Berg RMG, Olufsen MS. Characterization of differences in immune responses during bolus and continuous infusion endotoxin challenges using mathematical modelling. Exp Physiol 2024; 109:689-710. [PMID: 38466166 PMCID: PMC11061636 DOI: 10.1113/ep091552] [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: 11/03/2023] [Accepted: 02/13/2024] [Indexed: 03/12/2024]
Abstract
Endotoxin administration is commonly used to study the inflammatory response, and though traditionally given as a bolus injection, it can be administered as a continuous infusion over multiple hours. Several studies hypothesize that the latter better represents the prolonged and pronounced inflammation observed in conditions like sepsis. Yet very few experimental studies have administered endotoxin using both strategies, leaving significant gaps in determining the underlying mechanisms responsible for their differing immune responses. We used mathematical modelling to analyse cytokine data from two studies administering a 2 ng kg-1 dose of endotoxin, one as a bolus and the other as a continuous infusion over 4 h. Using our model, we simulated the dynamics of mean and subject-specific cytokine responses as well as the response to long-term endotoxin administration. Cytokine measurements revealed that the bolus injection led to significantly higher peaks for interleukin (IL)-8, while IL-10 reaches higher peaks during continuous administration. Moreover, the peak timing of all measured cytokines occurred later with continuous infusion. We identified three model parameters that significantly differed between the two administration methods. Monocyte activation of IL-10 was greater during the continuous infusion, while tumour necrosis factor α $ {\alpha} $ and IL-8 recovery rates were faster for the bolus injection. This suggests that a continuous infusion elicits a stronger, longer-lasting systemic reaction through increased stimulation of monocyte anti-inflammatory mediator production and decreased recovery of pro-inflammatory catalysts. Furthermore, the continuous infusion model exhibited prolonged inflammation with recurrent peaks resolving within 2 days during long-term (20-32 h) endotoxin administration.
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Affiliation(s)
| | - Susanne Janum
- Frederiksberg and Bispebjerg HospitalsFrederiksbergDenmark
- Department of Biomedical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Ronan M. G. Berg
- Department of Biomedical SciencesUniversity of CopenhagenCopenhagenDenmark
- Department of Clinical Physiology and Nuclear Medicine and, Centre for Physical Activity ResearchCopenhagen University HospitalCopenhagenDenmark
- Neurovascular Research LaboratoryUniversity of South WalesPontypriddUK
| | - Mette S. Olufsen
- Department of MathematicsNorth Carolina State UniversityRaleighNorth CarolinaUSA
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4
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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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5
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Olsen MH, Riberholt C, Plovsing RR, Berg RMG, Møller K. Diagnostic and prognostic performance of Mxa and transfer function analysis-based dynamic cerebral autoregulation metrics. J Cereb Blood Flow Metab 2022; 42:2164-2172. [PMID: 36008917 PMCID: PMC9580178 DOI: 10.1177/0271678x221121841] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 07/19/2022] [Accepted: 07/29/2022] [Indexed: 11/16/2022]
Abstract
Dynamic cerebral autoregulation is often assessed by continuously recorded arterial blood pressure (ABP) and transcranial Doppler-derived mean cerebral blood flow velocity followed by analysis in the time and frequency domain, respectively. Sequential correlation (in the time domain, yielding e.g., the measure mean flow index, Mxa) and transfer function analysis (TFA) (in the frequency domain, yielding, e.g., normalised and non-normalised gain as well as phase in the low frequency domain) are commonly used approaches. This study investigated the diagnostic and prognostic performance of these metrics. We included recordings from 48 healthy volunteers, 19 patients with sepsis, 36 with traumatic brain injury (TBI), and 14 patients admitted to a neurorehabilitation unit. The diagnostic (between healthy volunteers and patients) and prognostic performance (to predict death or poor functional outcome) of Mxa and the TFA measures were assessed by area under the receiver-operating characteristic (AUROC) curves. AUROC curves generally indicated that the measures were 'no better than chance' (AUROC ∼0.5) both for distinguishing between healthy volunteers and patient groups, and for predicting outcomes in our cohort. No metric emerged as superior for distinguishing between healthy volunteers and different patient groups, for assessing the effect of interventions, or for predicting mortality or functional outcome.
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Affiliation(s)
- Markus Harboe Olsen
- Department of Neuroanaesthesiology, Neuroscience Centre, Copenhagen University Hospital – Rigshospitalet, Denmark
| | - Christian Riberholt
- Department of Neuroanaesthesiology, Neuroscience Centre, Copenhagen University Hospital – Rigshospitalet, Denmark
- Department of Neurorehabilitation/Traumatic Brain Injury, Copenhagen University Hospital – Rigshospitalet, Denmark
| | - Ronni R Plovsing
- Department of Anaesthesia, Hvidovre Hospital, University of Copenhagen, Copenhagen, Denmark
- Institute of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ronan MG Berg
- Department of Clinical Physiology, Nuclear Medicine & PET, Copenhagen University Hospital – Rigshospitalet, Denmark
- Centre for Physical Activity Research, Copenhagen University Hospital – Rigshospitalet, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Kirsten Møller
- Department of Neuroanaesthesiology, Neuroscience Centre, Copenhagen University Hospital – Rigshospitalet, Denmark
- Institute of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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6
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Vedrenne-Cloquet M, Chareyre J, Léger PL, Genuini M, Renolleau S, Oualha M. Low Dosing Norepinephrine Effects on Cerebral Oxygenation and Perfusion During Pediatric Shock. Front Pediatr 2022; 10:898444. [PMID: 35874564 PMCID: PMC9298794 DOI: 10.3389/fped.2022.898444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 05/16/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Cerebral hypoperfusion and impaired oxygen delivery during pediatric critical illness may result in acute neurologic injury with subsequent long-term effects on neurodevelopmental outcome. Yet, the impact of norepinephrine on cerebral hemodynamics is unknown in children with shock. We aimed to describe the norepinephrine effects on cerebral perfusion and oxygenation during pediatric shock. PATIENTS AND METHODS We conducted an observational multicentre prospective study in 3 French pediatric intensive care units. Children <18 years of age excluding traumatic brain injury were included in the study if they need norepinephrine for shock. Systemic and cerebral hemodynamics were compared between the time of initiation of norepinephrine (T0), and the steady-state (Tss). Cardiac output (CO) was measured using ultrasound. Cerebral perfusion was assessed on middle cerebral arteries (MCA) using transcranial doppler ultrasound. Cerebral tissue oxygen saturation (rScO2) was recorded using near infrared spectroscopy, and we calculated cerebral fractional tissue oxygen extraction (cFTOE = SpO2-rScO2/SpO2). MAIN RESULTS Fourteen children (median [IQR] age of 3.5[1; 13.5] years) were included. Norepinephrine at 0.2[0.1; 0.32] μg/kg/min significantly increased mean arterial blood pressure (61[56; 73] mmHg at Tss vs. 49[42;54] mmHg at T0, p=10-3) without change of CO. MCA velocities, pulsatility index, rScO2, and cFTOE did not significantly change between T0 and Tss. Some individuals observed variations in estimated CBF, which slightly improved in 7 patients, remained unchanged in 5, and was impaired in 2. No patient experienced significant variations of rScO2. CONCLUSIONS Low-dosing norepinephrine, despite a homogeneous and significant increase in arterial blood pressure, had little effects on cerebral perfusion and oxygenation during pediatric shock. This reinforces the need for personalized tailored therapies in this population. TRIAL REGISTRATION Clinicaltrials.gov, NCT03731104. Registered 6 November, 2018. https://clinicaltrials.gov/ct2/show/NCT03731104.
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Affiliation(s)
| | - Judith Chareyre
- Pediatric Intensive Care Unit, AP-HP CHU Necker-Enfants Malades, Paris, France
| | - Pierre-Louis Léger
- Pediatric Intensive Care Unit, AP-HP CHU Trousseau-La Roche Guyon, Paris, France
| | - Mathieu Genuini
- Pediatric Intensive Care Unit, AP-HP CHU Robert Debré, Paris, France.,Pediatric Intensive Care Transport Unit, AP-HP CHU Robert Debré, Paris, France
| | - Sylvain Renolleau
- Pediatric Intensive Care Unit, AP-HP CHU Necker-Enfants Malades, Paris, France
| | - Mehdi Oualha
- Pediatric Intensive Care Unit, AP-HP CHU Necker-Enfants Malades, Paris, France
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7
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Eleveld N, Hoedemaekers CWE, van Kaam CR, Leijte GP, van den Brule JMD, Pickkers P, Aries MJH, Maurits NM, Elting JWJ. Near-Infrared Spectroscopy-Derived Dynamic Cerebral Autoregulation in Experimental Human Endotoxemia-An Exploratory Study. Front Neurol 2021; 12:695705. [PMID: 34566840 PMCID: PMC8461327 DOI: 10.3389/fneur.2021.695705] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 08/11/2021] [Indexed: 11/13/2022] Open
Abstract
Cerebral perfusion may be altered in sepsis patients. However, there are conflicting findings on cerebral autoregulation (CA) in healthy participants undergoing the experimental endotoxemia protocol, a proxy for systemic inflammation in sepsis. In the current study, a newly developed near-infrared spectroscopy (NIRS)-based CA index is investigated in an endotoxemia study population, together with an index of focal cerebral oxygenation. Methods: Continuous-wave NIRS data were obtained from 11 healthy participants receiving a continuous infusion of bacterial endotoxin for 3 h (ClinicalTrials.gov NCT02922673) under extensive physiological monitoring. Oxygenated–deoxygenated hemoglobin phase differences in the (very)low frequency (VLF/LF) bands and the Tissue Saturation Index (TSI) were calculated at baseline, during systemic inflammation, and at the end of the experiment 7 h after the initiation of endotoxin administration. Results: The median (inter-quartile range) LF phase difference was 16.2° (3.0–52.6°) at baseline and decreased to 3.9° (2.0–8.8°) at systemic inflammation (p = 0.03). The LF phase difference increased from systemic inflammation to 27.6° (12.7–67.5°) at the end of the experiment (p = 0.005). No significant changes in VLF phase difference were observed. The TSI (mean ± SD) increased from 63.7 ± 3.4% at baseline to 66.5 ± 2.8% during systemic inflammation (p = 0.03) and remained higher at the end of the experiment (67.1 ± 4.2%, p = 0.04). Further analysis did not reveal a major influence of changes in several covariates such as blood pressure, heart rate, PaCO2, and temperature, although some degree of interaction could not be excluded. Discussion: A reversible decrease in NIRS-derived cerebral autoregulation phase difference was seen after endotoxin infusion, with a small, sustained increase in TSI. These findings suggest that endotoxin administration in healthy participants reversibly impairs CA, accompanied by sustained microvascular vasodilation.
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Affiliation(s)
- Nick Eleveld
- Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Cornelia W E Hoedemaekers
- Department of Intensive Care Medicine, Radboud University Medical Center, Radboud University, Nijmegen, Netherlands
| | - C Ruud van Kaam
- Department of Intensive Care Medicine, Radboud University Medical Center, Radboud University, Nijmegen, Netherlands
| | - Guus P Leijte
- Department of Intensive Care Medicine, Radboud University Medical Center, Radboud University, Nijmegen, Netherlands.,Radboud Center for Infectious Diseases (RCI), Radboud University Medical Center, Radboud University, Nijmegen, Netherlands
| | - Judith M D van den Brule
- Department of Intensive Care Medicine, Radboud University Medical Center, Radboud University, Nijmegen, Netherlands
| | - Peter Pickkers
- Department of Intensive Care Medicine, Radboud University Medical Center, Radboud University, Nijmegen, Netherlands.,Radboud Center for Infectious Diseases (RCI), Radboud University Medical Center, Radboud University, Nijmegen, Netherlands
| | - Marcel J H Aries
- Department of Intensive Care Medicine, School of Mental Health and NeuroSciences (MHeNS), University Medical Center Maastricht (MUMC+), Maastricht University, Maastricht, Netherlands
| | - Natasha M Maurits
- Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Jan Willem J Elting
- Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
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8
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Olsen MH, Riberholt CG, Plovsing RR, Møller K, Berg RMG. Reliability of the mean flow index (Mx) for assessing cerebral autoregulation in healthy volunteers. Physiol Rep 2021; 9:e14923. [PMID: 34173717 PMCID: PMC8234479 DOI: 10.14814/phy2.14923] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 05/13/2021] [Accepted: 05/17/2021] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Mean flow index (Mxa) for evaluating dynamic cerebral autoregulation is derived using varying approaches for calculation, which may explain that the reliability ranges from poor to excellent. The comparability, repeatability, stability, and internal consistency of approaches have not previously been assessed. METHODS We included 60 recordings from resting healthy volunteers and calculated Mxa using four different approaches: three without overlapping calculations, using intervals for averaging wave-form data (blocks) of 3, 6, and 10 s, and correlation periods (epochs) of 60, 240, and 300 s (3-60-F, 6-240-F, and 10-300-F); and one using 10-second blocks, 300 s epochs, and overlaps of 60 s (10-300-60). The comparability between the approaches was assessed using Student's t test, intraclass correlation coefficients (ICC), and Bland-Altman plot. RESULTS Overall, 3-60-F resulted in a higher Mxa than the other indices (p < 0.001, for all). The reliability when comparing all the approaches ranged from moderate to good (ICC: 0.68; 95%CI: 0.59-0.84), which was primarily due to similarities between 10-300-F and 10-300-60 (ICC: 0.94; 95%CI: 0.86-0.98). The reliability when comparing the first and last half was poor for 10-300-F and ranged from poor to moderate for the other approaches. Additional random artifacts resulted in poor reliability for 10-300-F, while the other approaches were more stable. CONCLUSIONS Mxa in general has a low sensitivity to artifacts, but otherwise seems highly dependent on the approach, with a repeatability that is moderate at best. The varying accuracy and precision renders Mxa unreliable for classifying impaired cerebral autoregulation when using healthy adults for comparison.
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Affiliation(s)
- Markus H. Olsen
- Department of NeuroanaesthesiologyCopenhagen University HospitalRigshospitaletDenmark
| | - Christian G. Riberholt
- Department of NeuroanaesthesiologyCopenhagen University HospitalRigshospitaletDenmark
- Department of Neurorehabilitation / Traumatic Brain Injury UnitCopenhagen University HospitalRigshospitaletDenmark
| | - Ronni R. Plovsing
- Department of AnaesthesiaHvidovre HospitalUniversity of CopenhagenCopenhagenDenmark
- Institute of Clinical MedicineFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Kirsten Møller
- Department of NeuroanaesthesiologyCopenhagen University HospitalRigshospitaletDenmark
- Institute of Clinical MedicineFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Ronan M. G. Berg
- Department of Clinical Physiology, Nuclear Medicine & PETCopenhagen University HospitalRigshospitaletDenmark
- Centre for Physical Activity ResearchCopenhagen University HospitalRigshospitaletDenmark
- Department of Biomedical SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
- Neurovascular Research LaboratoryFaculty of Life Sciences and EducationUniversity of South WalesPontypriddUK
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9
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Chowhan G, Kundu R, Maitra S, Arora MK, Batra RK, Subramaniam R, Baidya DK, Trikha A. Efficacy of Left Ventricular Outflow Tract and Carotid Artery Velocity Time Integral as Predictors of Fluid Responsiveness in Patients with Sepsis and Septic Shock. Indian J Crit Care Med 2021; 25:310-316. [PMID: 33790513 PMCID: PMC7991757 DOI: 10.5005/jp-journals-10071-23764] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background: Transthoracic echocardiography is a reliable method to measure a dynamic change in left ventricular outflow tract velocity time integral (LVOTVTI) and stroke volume (SV) in response to passive leg raising (PLR) and can predict fluid responsiveness in critically ill patients. Measuring carotid artery velocity time integral (CAVTI) is easier, does not depend on adequate cardiac window, and requires less skill and expertise than LVOTVTI. The aim of this study is to identify the efficacy of ΔCAVTI and ΔLVOTVTI pre- and post-PLR in predicting fluid responsiveness in critically ill patients with sepsis and septic shock. Methods: After the institutional ethics committee's clearance and informed written consent, 60 critically ill mechanically ventilated patients aged 18-65 years were recruited in this prospective parallel-group study with 20 patients in each group: sepsis (group S), septic shock (group SS), and control (group C). Demographic parameters and baseline acute physiology, age and chronic health evaluation-II and sequential organ failure assessment scores were noted. LVOTVTI, SV, and CAVTI were measured before and after PLR along with other hemodynamic variables. Patients having a change in SV more than 15% following PLR were defined as "responders." Results: Twenty-three patients (38.33%) were responders. Area under receiver-operating characteristic curve for ΔCAVTI could predict responders in control and sepsis patients only. The correlation coefficients between pre- and post-PLR ΔCAVTI and ΔLVOTVTI were 0.530 (p = 0.016), 0.440 (p = 0.052), and 0.044 (p = 0.853) in control, sepsis, and septic shock patients, respectively. Conclusion: Following PLR, ΔCAVTI does not predict fluid responsiveness in septic shock patients and the correlation between ΔCAVTI and ΔLVOTVTI is weak in septic shock patients and only modest in sepsis patients. How to cite this article: Chowhan G, Kundu R, Maitra S, Arora MK, Batra RK, Subramaniam R, et al. Efficacy of Left Ventricular Outflow Tract and Carotid Artery Velocity Time Integral as Predictors of Fluid Responsiveness in Patients with Sepsis and Septic Shock. Indian J Crit Care Med 2021;25(3):310-316. CTRI/Trial Reg No: www.ctri.nic.in, CTRI/2017/11/010434.
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Affiliation(s)
- Ganesh Chowhan
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, India
| | - Riddhi Kundu
- Department of Critical Care Medicine, Manipal Hospitals, Dwarka, New Delhi, India
| | - Souvik Maitra
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, India
| | - Mahesh K Arora
- Department of Liver Transplant, Anaesthesia and Critical Care, Institute of Liver and Biliary Sciences, New Delhi, India
| | - Ravinder K Batra
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, India
| | - Rajeshwari Subramaniam
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, India
| | - Dalim K Baidya
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, India
| | - Anjan Trikha
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, India
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10
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Ferlini L, Su F, Creteur J, Taccone FS, Gaspard N. Cerebral autoregulation and neurovascular coupling are progressively impaired during septic shock: an experimental study. Intensive Care Med Exp 2020; 8:44. [PMID: 32797301 PMCID: PMC7426896 DOI: 10.1186/s40635-020-00332-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 07/21/2020] [Indexed: 12/14/2022] Open
Abstract
Background Alteration of the mechanisms of cerebral blood flow (CBF) regulation might contribute to the pathophysiology of sepsis-associated encephalopathy (SAE). However, previous clinical studies on dynamic cerebral autoregulation (dCA) in sepsis had several cofounders. Furthermore, little is known on the potential impairment of neurovascular coupling (NVC) in sepsis. The aim of our study was to determine the presence and time course of dCA and NVC alterations in a clinically relevant animal model and their potential impact on the development of SAE. Methods Thirty-six anesthetized, mechanically ventilated female sheep were randomized to sham procedures (sham, n = 15), sepsis (n = 14), or septic shock (n = 7). Blood pressure, CBF, and electrocorticography were continuously recorded. Pearson’s correlation coefficient Lxa and transfer function analysis were used to estimate dCA. NVC was assessed by the analysis of CBF variations induced by cortical gamma activity (Eγ) peaks and by the magnitude-squared coherence (MSC) between the spontaneous fluctuations of CBF and Eγ. Cortical function was estimated by the alpha-delta ratio. Wilcoxon signed rank and rank sum tests, Friedman tests, and RMANOVA test were used as appropriate. Results Sepsis and sham animals did not differ neither in dCA nor in NVC parameters. A significant impairment of dCA occurred only after septic shock (Lxa, p = 0.03, TFA gain p = 0.03, phase p = 0.01). Similarly, NVC was altered during septic shock, as indicated by a lower MSC in the frequency band 0.03–0.06 Hz (p < 0.001). dCA and NVC impairments were associated with cortical dysfunction (reduction in the alpha-delta ratio (p = 0.03)). Conclusions A progressive loss of dCA and NVC occurs during septic shock and is associated with cortical dysfunction. These findings indicate that the alteration of mechanisms controlling cortical perfusion plays a late role in the pathophysiology of SAE and suggest that alterations of CBF regulation mechanisms in less severe phases of sepsis reported in clinical studies might be due to patients’ comorbidities or other confounders. Furthermore, a mean arterial pressure targeting therapy aiming to optimize dCA might not be sufficient to prevent neuronal dysfunction in sepsis since it would not improve NVC.
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Affiliation(s)
- Lorenzo Ferlini
- Department of Neurology, Erasme Hospital, Université Libre de Bruxelles, Route de Lennik 808, 1070, Bruxelles, Belgium.
| | - Fuhong Su
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Bruxelles, Belgium
| | - Jacques Creteur
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Bruxelles, Belgium
| | - Fabio Silvio Taccone
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Bruxelles, Belgium
| | - Nicolas Gaspard
- Department of Neurology, Erasme Hospital, Université Libre de Bruxelles, Route de Lennik 808, 1070, Bruxelles, Belgium
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11
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Brooks D, Barr LC, Wiscombe S, McAuley DF, Simpson AJ, Rostron AJ. Human lipopolysaccharide models provide mechanistic and therapeutic insights into systemic and pulmonary inflammation. Eur Respir J 2020; 56:13993003.01298-2019. [PMID: 32299854 DOI: 10.1183/13993003.01298-2019] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 03/18/2020] [Indexed: 02/07/2023]
Abstract
Inflammation is a key feature in the pathogenesis of sepsis and acute respiratory distress syndrome (ARDS). Sepsis and ARDS continue to be associated with high mortality. A key contributory factor is the rudimentary understanding of the early events in pulmonary and systemic inflammation in humans, which are difficult to study in clinical practice, as they precede the patient's presentation to medical services. Lipopolysaccharide (LPS), a constituent of the outer membrane of Gram-negative bacteria, is a trigger of inflammation and the dysregulated host response in sepsis. Human LPS models deliver a small quantity of LPS to healthy volunteers, triggering an inflammatory response and providing a window to study early inflammation in humans. This allows biological/mechanistic insights to be made and new therapeutic strategies to be tested in a controlled, reproducible environment from a defined point in time. We review the use of human LPS models, focussing on the underlying mechanistic insights that have been gained by studying the response to intravenous and pulmonary LPS challenge. We discuss variables that may influence the response to LPS before considering factors that should be considered when designing future human LPS studies.
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Affiliation(s)
- Daniel Brooks
- Institute of Cellular Medicine, Newcastle University, Newcastle Upon Tyne, UK
| | - Laura C Barr
- Dept of Respiratory Medicine, Royal Infirmary of Edinburgh, Edinburgh, UK
| | - Sarah Wiscombe
- Institute of Cellular Medicine, Newcastle University, Newcastle Upon Tyne, UK
| | - Daniel F McAuley
- School of Medicine, Dentistry and Biomedical Sciences, Institute for Health Sciences, Wellcome-Wolfson Institute for Experimental Medicine, Belfast, UK
| | - A John Simpson
- Institute of Cellular Medicine, Newcastle University, Newcastle Upon Tyne, UK
| | - Anthony J Rostron
- Institute of Cellular Medicine, Newcastle University, Newcastle Upon Tyne, UK
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12
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Dahl RH, Berg RMG, Taudorf S, Bailey DM, Lundby C, Christensen M, Larsen FS, Møller K. Transcerebral exchange kinetics of large neutral amino acids during acute inspiratory hypoxia in humans. Scandinavian Journal of Clinical and Laboratory Investigation 2019; 79:595-600. [PMID: 31657241 DOI: 10.1080/00365513.2019.1683762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Hypoxaemia is present in many critically ill patients, and may contribute to encephalopathy. Changes in the passage of large neutral amino acids (LNAAs) across the blood-brain barrier (BBB) with an increased cerebral influx of aromatic amino acids into the brain may concurrently be present and also contribute to encephalopathy, but it has not been established whether hypoxaemia per se may trigger such changes. We measured cerebral blood flow (CBF) in 11 healthy men using the Kety-Schmidt technique and obtained paired arterial and jugular-venous blood samples for the determination of LNAAs by high performance liquid chromatography at baseline and after 9 hours of poikilocapnic normobaric hypoxia (12% O2). Transcerebral net exchange was determined by the Fick principle, and transport of LNAAs across the BBB was determined mathematically. Hypoxia increased both the systemic and corresponding cerebral delivery of the aromatic amino acid phenylalanine, and the branched-chain amino acids leucine and isoleucine. Despite this, the transcerebral net exchange values and mathematically derived brain extracellular concentrations for all LNAAs were unaffected. In conclusion, the observed changes in circulating LNAAs triggered by hypoxaemia do not affect the transcerebral exchange kinetics of LNAAs to such an extent that their brain extracellular concentrations are affected.
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Affiliation(s)
- Rasmus H Dahl
- Department of Neuroanaesthesiology, Rigshospitalet, Copenhagen, Denmark
| | - Ronan M G Berg
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontyprid, UK
| | - Sarah Taudorf
- Department of Neurology 2082, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Damian M Bailey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontyprid, UK
| | - Carsten Lundby
- Centre for Physical Activity Research, Rigshospitalet, Copenhagen, Denmark
| | - Mette Christensen
- Department of Clinical Genetics, Rigshospitalet, Copenhagen, Denmark
| | - Fin S Larsen
- Department of Hepatology, Rigshospitalet, Copenhagen, Denmark
| | - Kirsten Møller
- Department of Neuroanaesthesiology, Rigshospitalet, Copenhagen, Denmark
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13
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Thudium M, Ellerkmann RK, Heinze I, Hilbert T. Relative cerebral hyperperfusion during cardiopulmonary bypass is associated with risk for postoperative delirium: a cross-sectional cohort study. BMC Anesthesiol 2019; 19:35. [PMID: 30851736 PMCID: PMC6408763 DOI: 10.1186/s12871-019-0705-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 02/25/2019] [Indexed: 12/19/2022] Open
Abstract
Background Our objective was to evaluate if changes in on-pump cerebral blood flow, relative to the pre-bypass baseline, are associated with the risk for postoperative delirium (POD) following cardiac surgery. Methods In 47 consecutive adult patients, right middle cerebral artery blood flow velocity (MCAV) was assessed using transcranial Doppler sonography. Individual values, measured during cardiopulmonary bypass (CPB), were normalized to the pre-bypass baseline value and termed MCAVrel. An MCAVrel > 100% was defined as cerebral hyperperfusion. Prevalence of POD was assessed using the Confusion Assessment Method for the Intensive Care Unit. Results Overall prevalence of POD was 27%. In the subgroup without POD, 32% of patients had experienced relative cerebral hyperperfusion during CPB, compared to 67% in the subgroup with POD (p < 0.05). The mean averaged MCAVrel was 90 (±21) % in the no-POD group vs. 112 (±32) % in the POD group (p < 0.05), and patients developing delirium experienced cerebral hyperperfusion during CPB for about 39 (±35) min, compared to 6 (±11) min in the group without POD (p < 0.001). In a subcohort with pre-bypass baseline MCAV (MCAVbas) below the median MCAVbas of the whole cohort, prevalence of POD was 17% when MCAVrel during CPB was kept below 100%, but increased to 53% when these patients actually experienced relative cerebral hyperperfusion. Conclusions Our results suggest a critical role for cerebral hyperperfusion in the pathogenesis of POD following on-pump open-heart surgery, recommending a more individualized hemodynamic management, especially in the population at risk. Electronic supplementary material The online version of this article (10.1186/s12871-019-0705-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Marcus Thudium
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Bonn, Sigmund-Freud-Strasse 25, 53127, Bonn, Germany
| | - Richard K Ellerkmann
- Department of Anesthesiology and Intensive Care Medicine, Dortmund Hospital, Beurhausstrasse 40, 44137, Dortmund, Germany
| | - Ingo Heinze
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Bonn, Sigmund-Freud-Strasse 25, 53127, Bonn, Germany
| | - Tobias Hilbert
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Bonn, Sigmund-Freud-Strasse 25, 53127, Bonn, Germany.
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14
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Rivera-Lara L. The role of impaired brain perfusion in septic encephalopathy. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2019; 23:54. [PMID: 30782168 PMCID: PMC6381612 DOI: 10.1186/s13054-018-2299-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 12/21/2018] [Indexed: 11/21/2022]
Affiliation(s)
- Lucia Rivera-Lara
- Department of Neurology, The Johns Hopkins University School of Medicine, 600 N Wolfe Street, Phipps 455, Baltimore, MD, 21287, USA. .,Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, 600 N Wolfe Street, Phipps 455, Baltimore, MD, 21287, USA.
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15
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Rosenblatt K, Walker KA, Goodson C, Olson E, Maher D, Brown CH, Nyquist P. Cerebral Autoregulation-Guided Optimal Blood Pressure in Sepsis-Associated Encephalopathy: A Case Series. J Intensive Care Med 2019; 35:1453-1464. [PMID: 30760173 PMCID: PMC6692246 DOI: 10.1177/0885066619828293] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Impaired cerebral autoregulation and cerebral hypoperfusion may play a critical role in the high morbidity and mortality in patients with sepsis-associated encephalopathy (SAE). Bedside assessment of cerebral autoregulation may help individualize hemodynamic targets that optimize brain perfusion. We hypothesize that near-infrared spectroscopy (NIRS)-derived cerebral oximetry can identify blood pressure ranges that enhance autoregulation in patients with SAE and that disturbances in autoregulation are associated with severity of encephalopathy. METHODS Adult patients with acute encephalopathy directly attributable to sepsis were followed using NIRS-based multimodal monitoring for 12 consecutive hours. We used the correlation in time between regional cerebral oxygen saturation and mean arterial pressure (MAP) to determine the cerebral oximetry index (COx) as a measure of cerebral autoregulation. Autoregulation curves were constructed for each patient with averaged COx values sorted by MAP in 3 sequential 4-hour periods; the optimal pressure (MAPOPT), defined as the MAP associated with most robust autoregulation (lowest COx), was identified in each period. Severity of encephalopathy was measured with Glasgow coma scale (GCS). RESULTS Six patients with extracranial sepsis met the stringent criteria specified, including no pharmacological sedation or neurologic premorbidity. Optimal MAP was identified in all patients and ranged from 55 to 115 mmHg. Additionally, MAPOPT varied within individual patients over time during monitoring. Disturbed autoregulation, based on COx, was associated with worse neurologic status (GCS < 13) both with and without controlling for age and severity of sepsis (adjusted odds ratio [OR]: 2.11; 95% confidence interval [CI]: 1.77-2.52; P < .001; OR: 2.97; 95% CI: 1.63-5.43; P < .001). CONCLUSIONS In this high-fidelity group of patients with SAE, continuous, NIRS-based monitoring can identify blood pressure ranges that improve autoregulation. This is important given the association between cerebral autoregulatory function and severity of encephalopathy. Individualizing blood pressure goals using bedside autoregulation monitoring may better preserve cerebral perfusion in SAE than current practice.
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Affiliation(s)
- Kathryn Rosenblatt
- Department of Anesthesiology and Critical Care Medicine, 1466Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Neurology, 1466Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Keenan A Walker
- Department of Neurology, 1466Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Carrie Goodson
- Department of Pulmonary and Critical Care, 1466Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Elsa Olson
- Department of Anesthesiology and Critical Care Medicine, 1466Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Dermot Maher
- Department of Anesthesiology and Critical Care Medicine, 1466Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Charles H Brown
- Department of Anesthesiology and Critical Care Medicine, 1466Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Paul Nyquist
- Department of Anesthesiology and Critical Care Medicine, 1466Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Neurology, 1466Johns Hopkins University School of Medicine, Baltimore, MD, USA
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16
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Crippa IA, Subirà C, Vincent JL, Fernandez RF, Hernandez SC, Cavicchi FZ, Creteur J, Taccone FS. Impaired cerebral autoregulation is associated with brain dysfunction in patients with sepsis. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2018; 22:327. [PMID: 30514349 PMCID: PMC6280405 DOI: 10.1186/s13054-018-2258-8] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 11/07/2018] [Indexed: 12/12/2022]
Abstract
Background Sepsis-associated brain dysfunction (SABD) is associated with high morbidity and mortality. The pathophysiology of SABD is multifactorial. One hypothesis is that impaired cerebral autoregulation (CAR) may result in brain hypoperfusion and neuronal damage leading to SABD. Methods We studied 100 adult patients with sepsis (July 2012–March 2017) (age = 62 [52–71] years; Acute Physiology and Chronic Health Evaluation II score on admission = 21 [15–26]). Exclusion criteria were acute or chronic intracranial disease, arrhythmias, extracorporeal membrane oxygenation, and known intra- or extracranial supra-aortic vessel disease. The site of infection was predominantly abdominal (46%) or pulmonary (28%). Transcranial Doppler was performed, insonating the left middle cerebral artery with a 2-MHz probe. Middle cerebral artery blood flow velocity (FV) and arterial blood pressure (ABP) signals were recorded simultaneously; Pearson’s correlation coefficient (mean flow index [Mxa]) between ABP and FV was calculated using MATLAB. Impaired CAR was defined as Mxa > 0.3. Results Mxa was 0.29 [0.05–0.62]. CAR was impaired in 50 patients (50%). In a multiple linear regression analysis, low mean arterial pressure, history of chronic kidney disease and fungal infection were associated with high Mxa. SABD was diagnosed in 57 patients (57%). In a multivariable analysis, altered cerebral autoregulation, mechanical ventilation and history of vascular disease were independent predictors of SABD. Conclusions Cerebral autoregulation was altered in half of the patients with sepsis and was associated with the development of SABD. These findings support the concept that cerebral hypoxia could contribute to the development of SABD. Electronic supplementary material The online version of this article (10.1186/s13054-018-2258-8) contains supplementary material, which is available to authorized users.
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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
| | - Carles Subirà
- Department of Intensive Care, Althaia Xarxa Assistencial Universitària de Manresa, Barcelona, Spain
| | - Jean-Louis Vincent
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik, 808, 1070, Brussels, Belgium
| | - Rafael Fernandez Fernandez
- Department of Intensive Care, Althaia Xarxa Assistencial Universitària de Manresa, Barcelona, Spain.,CIBERES, Madrid, Spain
| | - Silvia Cano Hernandez
- Department of Intensive Care, Althaia Xarxa Assistencial Universitària de Manresa, Barcelona, Spain
| | - Federica Zama Cavicchi
- Department of Intensive Care, 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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17
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Vasopressors Do Not Influence Cerebral Critical Closing Pressure During Systemic Inflammation Evoked by Experimental Endotoxemia and Sepsis in Humans. Shock 2018; 49:529-535. [DOI: 10.1097/shk.0000000000001003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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18
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Waltz X, Beaudin AE, Hanly PJ, Mitsis GD, Poulin MJ. Effects of continuous positive airway pressure and isocapnic-hypoxia on cerebral autoregulation in patients with obstructive sleep apnoea. J Physiol 2017; 594:7089-7104. [PMID: 27644162 DOI: 10.1113/jp272967] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/16/2016] [Indexed: 01/01/2023] Open
Abstract
KEY POINTS Altered cerebral autoregulation (CA) in obstructive sleep apnoea (OSA) patients may contribute to increased stroke risk in this population; the gold standard treatment for OSA is continuous positive airway pressure, which improves cerebrovascular regulation and may decrease the risk of stroke. Isocapnic-hypoxia impairs CA in healthy subjects, but it remains unknown in OSA whether impaired CA is further exacerbated by isocapnic-hypoxia and whether it is improved by treatment with continuous positive airway pressure. During normoxia, CA was altered in the more severe but not in the less severe OSA patients, while, in contrast, during isocapnic-hypoxia, CA was similar between groups and tended to improve in patients with more severe OSA compared to normoxia. From a clinical perspective, one month of continuous positive airway pressure treatment does not improve CA. From a physiological perspective, this study suggests that sympathetic overactivity may be responsible for altered CA in the more severe OSA patients. ABSTRACT Cerebral autoregulation (CA) impairment may contribute to the increased risk of stroke associated with obstructive sleep apnoea (OSA). It is unknown if impaired CA is further exacerbated by isocapnic-hypoxia and whether it is improved by treatment of OSA with continuous positive airway pressure (CPAP). CA was assessed during wakefulness in 53 OSA patients (50.3 ± 9.3 years) and 21 controls (49.8 ± 8.6 years) at baseline and following a minimum of 1 month of effective CPAP therapy (OSA patients, n = 40). Control participants (n = 21) performed a follow-up visit to control for time effects within OSA patients between baseline and the post-CPAP visit. Beat-by-beat middle cerebral artery blood flow velocity and mean arterial blood pressure (MBP), and breath-by-breath end-tidal partial pressure of CO2 (P ET ,CO2) were monitored. CA was determined during normoxia and isocapnic-hypoxia using transfer function (phase and gain) and coherence analysis (including multiple and partial coherence (using MBP and P ET ,CO2 as inputs)) in the very low frequency range (0.03-0.07 Hz). OSA patients were divided into two subgroups (less severe and more severe) based upon the median respiratory disturbance index (RDI). During normoxia, the more severe OSA patients (RDI 45.9 ± 10.3) exhibited altered CA compared to controls and the less severe OSA patients (RDI 24.5 ± 5.9). In contrast, during isocapnic-hypoxia, CA was similar between groups. CPAP had no effect on CA. In conclusion, CA is altered in the more severe OSA patients during normoxia but not during isocapnic-hypoxia and CPAP treatment does not impact CA.
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Affiliation(s)
- Xavier Waltz
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Andrew E Beaudin
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Patrick J Hanly
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Sleep Centre, Foothills Medical Centre, Calgary, AB, Canada
| | - Georgios D Mitsis
- Department of Bioengineering, McGill University, Montréal, Québec, Canada
| | - Marc J Poulin
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
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19
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de Jong DLK, Tarumi T, Liu J, Zhang R, Claassen JAHR. Lack of linear correlation between dynamic and steady-state cerebral autoregulation. J Physiol 2017; 595:5623-5636. [PMID: 28597991 PMCID: PMC5556173 DOI: 10.1113/jp274304] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 06/06/2017] [Indexed: 01/15/2023] Open
Abstract
Key points For correct application and interpretation of cerebral autoregulation (CA) measurements in research and in clinical care, it is essential to understand differences and similarities between dynamic and steady‐state CA. The present study found no correlation between dynamic and steady‐state CA indices in healthy older adults. There was variability between individuals in all (steady‐state and dynamic) autoregulatory indices, ranging from low (almost absent) to highly efficient CA in this healthy population. These findings challenge the assumption that assessment of a single CA parameter or a single set of parameters can be generalized to overall CA functioning. Therefore, depending on specific research purposes, the choice for either steady‐state or dynamic measures or both should be weighed carefully.
Abstract The present study aimed to investigate the relationship between dynamic (dCA) and steady‐state cerebral autoregulation (sCA). In 28 healthy older adults, sCA was quantified by a linear regression slope of proportionate (%) changes in cerebrovascular resistance (CVR) in response to proportionate (%) changes in mean blood pressure (BP) induced by stepwise sodium nitroprusside (SNP) and phenylephrine (PhE) infusion. Cerebral blood flow (CBF) was measured at the internal carotid artery (ICA) and vertebral artery (VA) and CBF velocity at the middle cerebral artery (MCA). With CVR = BP/CBF, Slope‐CVRICA, Slope‐CVRVA and Slope‐CVRiMCA were derived. dCA was assessed (i) in supine rest, analysed with transfer function analysis (gain and phase) and autoregulatory index (ARI) fit from spontaneous oscillations (ARIBaseline), and (ii) with transient changes in BP using a bolus injection of SNP (ARISNP) and PhE (ARIPhE). Comparison of sCA and dCA parameters (using Pearson's r for continuous and Spearman's ρ for ordinal parameters) demonstrated a lack of linear correlations between sCA and dCA measures. However, comparisons of parameters within dCA and within sCA were correlated. For sCA slope‐CVRVA with Slope‐CVRiMCA (r = 0.45, P < 0.03); for dCA ARISNP with ARIPhE (ρ = 0.50, P = 0.03), ARIBaseline (ρ = 0.57, P = 0.03) and PhaseLF (ρ = 0.48, P = 0.03); and for GainVLF with GainLF (r = 0.51, P = 0.01). By contrast to the commonly held assumption based on an earlier study, there were no linear correlations between sCA and dCA. As an additional observation, there was strong inter‐individual variability, both in dCA and sCA, in this healthy group of elderly, in a range from low to high CA efficiency. For correct application and interpretation of cerebral autoregulation (CA) measurements in research and in clinical care, it is essential to understand differences and similarities between dynamic and steady‐state CA. The present study found no correlation between dynamic and steady‐state CA indices in healthy older adults. There was variability between individuals in all (steady‐state and dynamic) autoregulatory indices, ranging from low (almost absent) to highly efficient CA in this healthy population. These findings challenge the assumption that assessment of a single CA parameter or a single set of parameters can be generalized to overall CA functioning. Therefore, depending on specific research purposes, the choice for either steady‐state or dynamic measures or both should be weighed carefully.
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Affiliation(s)
- Daan L K de Jong
- Donders Institute for Brain, Cognition and Behavior, Radboud Alzheimer Center, and Department of Geriatric Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Takashi Tarumi
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Texas, USA.,Department of Internal Medicine
| | - Jie Liu
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Texas, USA.,Department of Internal Medicine
| | - Rong Zhang
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Texas, USA.,Department of Internal Medicine.,Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Texas, USA
| | - Jurgen A H R Claassen
- Donders Institute for Brain, Cognition and Behavior, Radboud Alzheimer Center, and Department of Geriatric Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
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20
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Kooi EMW, Verhagen EA, Elting JWJ, Czosnyka M, Austin T, Wong FY, Aries MJ. Measuring cerebrovascular autoregulation in preterm infants using near-infrared spectroscopy: an overview of the literature. Expert Rev Neurother 2017. [DOI: 10.1080/14737175.2017.1346472] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Elisabeth M. W. Kooi
- Beatrix Children’s Hospital, Division of Neonatology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Elise A. Verhagen
- Sophia Children’s Hospital, University of Rotterdam, Erasmus University Hospital, Rotterdam, The Netherlands
| | - Jan Willem J. Elting
- Department of Neurology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Marek Czosnyka
- Department of Academic Neurosurgery, Addenbrooke’s Hospital, University of Cambridge, Cambridge, UK
| | - Topun Austin
- Cambridge University Hospitals NHS Foundation Trust, Rosie Hospital, Cambridge, UK
| | - Flora Y. Wong
- Monash Newborn, Monash Medical Centre; Department of Paediatrics, Monash University; The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Australia
| | - Marcel J.H. Aries
- Department of Intensive Care, University of Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
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21
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Etzerodt A, Berg RMG, Plovsing RR, Andersen MN, Bebien M, Habbeddine M, Lawrence T, Møller HJ, Moestrup SK. Soluble ectodomain CD163 and extracellular vesicle-associated CD163 are two differently regulated forms of 'soluble CD163' in plasma. Sci Rep 2017; 7:40286. [PMID: 28084321 PMCID: PMC5234032 DOI: 10.1038/srep40286] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 11/30/2016] [Indexed: 12/22/2022] Open
Abstract
CD163 is the macrophage receptor for uptake of hemoglobin-haptoglobin complexes. The human receptor can be shed from the macrophage surface owing to a cleavage site for the inflammation-inducible TACE/ADAM17 enzyme. Accordingly, plasma ‘soluble CD163’ (sCD163) has become a biomarker for macrophage activity and inflammation. The present study disclosed that 10% of sCD163 in healthy persons is actually extracellular vesicle (EV)-associated CD163 not being cleaved and shed. Endotoxin injection of human volunteers caused a selective increase in the ectodomain CD163, while septic patients exhibited high levels of both soluble ectodomain CD163 and extracellular vesicle (EV) CD163, the latter representing up 60% of total plasma CD163. A poor prognosis of septic patients measured as the sequential organ failure assessment (SOFA) score correlated with the increase in membrane-associated CD163. Our results show that soluble ectodomain CD163 and EV CD163 in plasma are part of separate macrophage response in the context of systemic inflammation. While that soluble ectodomain CD163 is released during the acute systemic inflammatory response, this is not the case for EV CD163 that instead may be released during a later phase of the inflammatory response. A separate measurement of the two forms of CD163 constituting ‘soluble CD163’ in plasma may therefore add to the diagnostic and prognostic value.
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Affiliation(s)
- Anders Etzerodt
- Department of Biomedicine, University of Aarhus, Aarhus, Denmark.,Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, Marseille, France
| | - Ronan M G Berg
- Centre of Inflammation and Metabolism, Rigshospitalet, Copenhagen, Denmark
| | - Ronni R Plovsing
- Department of Intensive Care, Rigshospitalet, Copenhagen, Denmark
| | - Morten N Andersen
- Department of Biomedicine, University of Aarhus, Aarhus, Denmark.,Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
| | - Magali Bebien
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, Marseille, France
| | - Mohamed Habbeddine
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, Marseille, France
| | - Toby Lawrence
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, Marseille, France
| | - Holger J Møller
- Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
| | - Søren K Moestrup
- Department of Biomedicine, University of Aarhus, Aarhus, Denmark.,Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark.,Department of Molecular Medicine, University of Southern Denmark, Denmark
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22
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Caldas JR, Panerai RB, Haunton VJ, Almeida JP, Ferreira GSR, Camara L, Nogueira RC, Bor-Seng-Shu E, Oliveira ML, Groehs RRV, Ferreira-Santos L, Teixeira MJ, Galas FRBG, Robinson TG, Jatene FB, Hajjar LA. Cerebral blood flow autoregulation in ischemic heart failure. Am J Physiol Regul Integr Comp Physiol 2016; 312:R108-R113. [PMID: 27927624 DOI: 10.1152/ajpregu.00361.2016] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 12/01/2016] [Accepted: 12/01/2016] [Indexed: 12/24/2022]
Abstract
Patients with ischemic heart failure (iHF) have a high risk of neurological complications such as cognitive impairment and stroke. We hypothesized that iHF patients have a higher incidence of impaired dynamic cerebral autoregulation (dCA). Adult patients with iHF and healthy volunteers were included. Cerebral blood flow velocity (CBFV, transcranial Doppler, middle cerebral artery), end-tidal CO2 (capnography), and arterial blood pressure (Finometer) were continuously recorded supine for 5 min at rest. Autoregulation index (ARI) was estimated from the CBFV step response derived by transfer function analysis using standard template curves. Fifty-two iHF patients and 54 age-, gender-, and BP-matched healthy volunteers were studied. Echocardiogram ejection fraction was 40 (20-45) % in iHF group. iHF patients compared with control subjects had reduced end-tidal CO2 (34.1 ± 3.7 vs. 38.3 ± 4.0 mmHg, P < 0.001) and lower ARI values (5.1 ± 1.6 vs. 5.9 ± 1.0, P = 0.012). ARI <4, suggestive of impaired CA, was more common in iHF patients (28.8 vs. 7.4%, P = 0.004). These results confirm that iHF patients are more likely to have impaired dCA compared with age-matched controls. The relationship between impaired dCA and neurological complications in iHF patients deserves further investigation.
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Affiliation(s)
- J R Caldas
- Department of Anesthesia, Heart Institute, University of São Paulo, São Paulo, Brazil.,Department of Neurosurgery, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil
| | - R B Panerai
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom; .,Leicester National Institute for Health Research Biomedical Research Unit in Cardiovascular Disease, Glenfield Hospital, Leicester, United Kingdom
| | - V J Haunton
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom.,Leicester National Institute for Health Research Biomedical Research Unit in Cardiovascular Disease, Glenfield Hospital, Leicester, United Kingdom
| | - J P Almeida
- Department of Anesthesia, Heart Institute, University of São Paulo, São Paulo, Brazil
| | - G S R Ferreira
- Department of Anesthesia, Heart Institute, University of São Paulo, São Paulo, Brazil
| | - L Camara
- Department of Anesthesia, Heart Institute, University of São Paulo, São Paulo, Brazil
| | - R C Nogueira
- Department of Neurosurgery, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil.,Department of Neurology, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil; and
| | - E Bor-Seng-Shu
- Department of Neurosurgery, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil
| | - M L Oliveira
- Department of Neurosurgery, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil
| | - R R V Groehs
- Department of Anesthesia, Heart Institute, University of São Paulo, São Paulo, Brazil
| | - L Ferreira-Santos
- Department of Anesthesia, Heart Institute, University of São Paulo, São Paulo, Brazil
| | - M J Teixeira
- Department of Neurosurgery, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil
| | - F R B G Galas
- Department of Anesthesia, Heart Institute, University of São Paulo, São Paulo, Brazil
| | - T G Robinson
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom.,Leicester National Institute for Health Research Biomedical Research Unit in Cardiovascular Disease, Glenfield Hospital, Leicester, United Kingdom
| | - F B Jatene
- Department of Cardiopneumology, Heart Institute, University of São Paulo, São Paulo, Brazil
| | - L A Hajjar
- Department of Cardiopneumology, Heart Institute, University of São Paulo, São Paulo, Brazil
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23
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Goodson CM, Rosenblatt K, Rivera-Lara L, Nyquist P, Hogue CW. Cerebral Blood Flow Autoregulation in Sepsis for the Intensivist: Why Its Monitoring May Be the Future of Individualized Care. J Intensive Care Med 2016; 33:63-73. [PMID: 27798314 DOI: 10.1177/0885066616673973] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cerebral blood flow (CBF) autoregulation maintains consistent blood flow across a range of blood pressures (BPs). Sepsis is a common cause of systemic hypotension and cerebral dysfunction. Guidelines for BP management in sepsis are based on historical concepts of CBF autoregulation that have now evolved with the availability of more precise technology for its measurement. In this article, we provide a narrative review of methods of monitoring CBF autoregulation, the cerebral effects of sepsis, and the current knowledge of CBF autoregulation in sepsis. Current guidelines for BP management in sepsis are based on a goal of maintaining mean arterial pressure (MAP) above the lower limit of CBF autoregulation. Bedside tools are now available to monitor CBF autoregulation continuously. These data reveal that individual BP goals determined from CBF autoregulation monitoring are more variable than previously expected. In patients undergoing cardiac surgery with cardiopulmonary bypass, for example, the lower limit of autoregulation varied between a MAP of 40 to 90 mm Hg. Studies of CBF autoregulation in sepsis suggest patients frequently manifest impaired CBF autoregulation, possibly a result of BP below the lower limit of autoregulation, particularly in early sepsis or with sepsis-associated encephalopathy. This suggests that the present consensus guidelines for BP management in sepsis may expose some patients to both cerebral hypoperfusion and cerebral hyperperfusion, potentially resulting in damage to brain parenchyma. The future use of novel techniques to study and clinically monitor CBF autoregulation could provide insight into the cerebral pathophysiology of sepsis and offer more precise treatments that may improve functional and cognitive outcomes for survivors of sepsis.
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Affiliation(s)
- Carrie M Goodson
- 1 Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kathryn Rosenblatt
- 2 Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,3 Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Lucia Rivera-Lara
- 2 Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,3 Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Paul Nyquist
- 2 Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,3 Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Charles W Hogue
- 4 Department of Anesthesiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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24
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Berg RMG. Myogenic and metabolic feedback in cerebral autoregulation: Putative involvement of arachidonic acid-dependent pathways. Med Hypotheses 2016; 92:12-7. [PMID: 27241246 DOI: 10.1016/j.mehy.2016.04.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 04/09/2016] [Accepted: 04/13/2016] [Indexed: 01/20/2023]
Abstract
The present paper presents a mechanistic model of cerebral autoregulation, in which the dual effects of the arachidonic acid metabolites 20-hydroxyeicosatetraenoic acid (20-HETE) and epoxyeicosatrienoic acids (EETs) on vascular smooth muscle mediate the cerebrovascular adjustments to a change in cerebral perfusion pressure (CPP). 20-HETE signalling in vascular smooth muscle mediates myogenic feedback to changes in vessel wall stretch, which may be modulated by metabolic feedback through EETs released from astrocytes and endothelial cells in response to changes in brain tissue oxygen tension. The metabolic feedback pathway is much faster than 20-HETE-dependent myogenic feedback, and the former thus initiates the cerebral autoregulatory response, while myogenic feedback comprises a relatively slower mechanism that functions to set the basal cerebrovascular tone. Therefore, assessments of dynamic cerebral autoregulation, which may provide information on the response time of the cerebrovasculature, may specifically be used to yield information on metabolic feedback mechanisms, while data based on assessments of static cerebral autoregulation represent the integrated functionality of myogenic and metabolic feedback.
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Affiliation(s)
- Ronan M G Berg
- Department of Clinical Physiology & Nuclear Medicine, Frederiksberg and Bispebjerg Hospitals, Frederiksberg, Denmark.
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25
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Berg RMG, Plovsing RR, Bailey DM, Holstein-Rathlou NH, Møller K. The Dynamic cerebral autoregulatory adaptive response to noradrenaline is attenuated during systemic inflammation in humans. Clin Exp Pharmacol Physiol 2016; 42:740-6. [PMID: 25966743 DOI: 10.1111/1440-1681.12421] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2015] [Revised: 03/17/2015] [Accepted: 05/07/2015] [Indexed: 11/28/2022]
Abstract
Vasopressor support is used widely for maintaining vital organ perfusion pressure in septic shock, with implications for dynamic cerebral autoregulation (dCA). This study investigated whether a noradrenaline-induced steady state increase in mean arterial blood pressure (MAP) would enhance dCA following lipopolysaccharide (LPS) infusion, a human-experimental model of the systemic inflammatory response during early sepsis. The dCA in eight healthy males was examined prior to and during an intended noradrenaline-induced MAP increase of approximately 30 mmHg. This was performed at baseline and repeated after a 4-h intravenous LPS infusion. The assessments of dCA were based on transfer function analysis of spontaneous oscillations between MAP and middle cerebral artery blood flow velocity measured by transcranial Doppler ultrasound in the low frequency range (0.07-0.20 Hz). Prior to LPS, noradrenaline administration was associated with a decrease in gain (1.18 (1.12-1.35) vs 0.93 (0.87-0.97) cm/mmHg per s; P < 0.05) with no effect on phase (0.71 (0.93-0.66) vs 0.94 (0.81-1.10) radians; P = 0.58). After LPS, noradrenaline administration changed neither gain (0.91 (0.85-1.01) vs 0.87 (0.81-0.97) cm/mmHg per s; P = 0.46) nor phase (1.10 (1.04-1.30) vs 1.37 (1.23-1.51) radians; P = 0.64). The improvement of dCA to a steady state increase in MAP is attenuated during an LPS-induced systemic inflammatory response. This may suggest that vasopressor treatment with noradrenaline offers no additional neuroprotective effect by enhancing dCA in patients with early sepsis.
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Affiliation(s)
- Ronan M G Berg
- Department of Clinical Physiology, Nuclear Medicine & PET, University Hospital Rigshospitalet, Copenhagen, Denmark.,Centre of Inflammation and Metabolism, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Ronni R Plovsing
- Intensive Care Unit 4131, University Hospital Rigshospitalet, Copenhagen, Denmark.,Department of Anaesthesiology, Køge Hospital, Køge, Denmark
| | - Damian M Bailey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK
| | - Niels-Henrik Holstein-Rathlou
- Renal and Vascular Research Section, Department of Biomedical Sciences, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kirsten Møller
- Centre of Inflammation and Metabolism, University Hospital Rigshospitalet, Copenhagen, Denmark.,Neurointensive Care Unit 2093, Department of Neuroanaesthesiology, University Hospital Rigshospitalet, Copenhagen, Denmark
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26
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Berg RMG, Plovsing RR. Effects of short-term mechanical hyperventilation on cerebral blood flow and dynamic cerebral autoregulation in critically ill patients with sepsis. Scandinavian Journal of Clinical and Laboratory Investigation 2016; 76:226-33. [PMID: 26935607 DOI: 10.3109/00365513.2015.1137350] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In sepsis, higher PaCO2 levels are associated with impaired dynamic cerebral autoregulation (dCA), which may expose the brain to hypo- and hyperperfusion during acute fluctuations in blood pressure. We hypothesised that short-term mechanical hyperventilation would dCA in critically ill patients with sepsis. Seven mechanically ventilated septic patients were included. We assessed dCA before and after 30 min of mechanical hyperventilation. Transfer function analysis of spontaneous oscillations in transcranial Doppler-based middle cerebral artery blood flow velocity (MCAv) and invasive mean arterial blood pressure was used to assess dCA. Mechanical enhance hyperventilation reduced the median PaCO2 from 5.3 (IQR, 5.0-6.5) to 4.7 (IQR, 4.2-5.1) kPa (p < 0.05). This was associated with a reduction in the median MCAv from 57 (IQR, 33-68) to 32 (IQR, 21-40) cm sec(-1) (p < 0.05). Apart from a small increase in gain in the low frequency range (2.32 [IQR 1.80-2.41] vs. 2.59 (2.40-4.64) cm mmHg(-1) sec(-1); p < 0.05), this was not associated with any enhancement in dCA. In conclusion, cerebral CO2 vasoreactivity was found to be preserved in septic patients; nevertheless, and in contrast to our working hypothesis, short-term mechanical hyperventilation did not enhance dCA.
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Affiliation(s)
- Ronan M G Berg
- a Department of Clinical Physiology and Nuclear Medicine , Bispebjerg and Frederiksberg Hospitals , Copenhagen ;,b Centre of Inflammation and Metabolism , University Hospital Rigshospitalet , Copenhagen
| | - Ronni R Plovsing
- c Department of Intensive Care 4131 , University Hospital Rigshospitalet , Copenhagen ;,d Department of Anaesthesiology , Køge Hospital , Køge , Denmark
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27
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Biomarkers of Delirium in a Low-Risk Community-Acquired Pneumonia-Induced Sepsis. Mol Neurobiol 2016; 54:722-726. [DOI: 10.1007/s12035-016-9708-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/07/2016] [Indexed: 11/26/2022]
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28
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Michels M, Steckert AV, Quevedo J, Barichello T, Dal-Pizzol F. Mechanisms of long-term cognitive dysfunction of sepsis: from blood-borne leukocytes to glial cells. Intensive Care Med Exp 2015; 3:30. [PMID: 26515197 PMCID: PMC4626467 DOI: 10.1186/s40635-015-0066-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 10/21/2015] [Indexed: 12/12/2022] Open
Abstract
Several mechanisms are associated with brain dysfunction during sepsis; one of the most important are activation of microglia and astrocytes. Activation of glial cells induces changes in permeability of the blood-brain barrier, secretion of inflammatory cytokines, and these alterations could induce neuronal dysfunction. Furthermore, blood-borne leukocytes can also reach the brain and participate in inflammatory response. Mechanisms involved in sepsis-associated brain dysfunction were revised here, focusing in neuroinflammation and involvement of blood-borne leukocytes and glial cells in this process.
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Affiliation(s)
- Monique Michels
- Laboratory of Experimental Pathophysiology, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciúma, SC, 88806-000, Brazil.
| | - Amanda V Steckert
- Laboratory of Neurosciences, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciúma, SC, Brazil.
| | - João Quevedo
- Laboratory of Neurosciences, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciúma, SC, Brazil.
- Center for Translational Psychiatry, Department of Psychiatry and Behavioral Sciences, Medical School, The University of Texas at Houston, Houston, TX, USA.
| | - Tatiana Barichello
- Laboratory of Neurosciences, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciúma, SC, Brazil.
- Center for Translational Psychiatry, Department of Psychiatry and Behavioral Sciences, Medical School, The University of Texas at Houston, Houston, TX, USA.
| | - Felipe Dal-Pizzol
- Laboratory of Experimental Pathophysiology, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciúma, SC, 88806-000, Brazil.
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29
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Berg RMG, Plovsing RR. Near-infrared spectroscopy versus transcranial Doppler ultrasound for assessing dynamic cerebral autoregulation by transfer function analysis in sepsis. Scandinavian Journal of Clinical and Laboratory Investigation 2015; 76:88-91. [PMID: 26450089 DOI: 10.3109/00365513.2015.1091495] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Ronan M G Berg
- a Department of Clinical Physiology , Nuclear Medicine & PET, University Hospital Rigshospitalet , Copenhagen.,b Centre of Inflammation and Metabolism, University Hospital Rigshospitalet , Copenhagen
| | - Ronni R Plovsing
- c Department of Intensive Care 4131 , University Hospital Rigshospitalet , Copenhagen.,d Department of Anaesthesiology , Køge Hospital , Køge , Denmark
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30
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Murkin JM, Kamar M, Silman Z, Balberg M, Adams SJ. Intraoperative Cerebral Autoregulation Assessment Using Ultrasound-Tagged Near-Infrared-Based Cerebral Blood Flow in Comparison to Transcranial Doppler Cerebral Flow Velocity: A Pilot Study. J Cardiothorac Vasc Anesth 2015; 29:1187-93. [DOI: 10.1053/j.jvca.2015.05.201] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Indexed: 11/11/2022]
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31
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Berg RMG, Plovsing RR, Bailey DM, Holstein-Rathlou NH, Møller K. Dynamic cerebral autoregulation to induced blood pressure changes in human experimental and clinical sepsis. Clin Physiol Funct Imaging 2015; 36:490-496. [PMID: 26017052 DOI: 10.1111/cpf.12256] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Accepted: 03/24/2015] [Indexed: 12/25/2022]
Abstract
Previous studies have demonstrated that dynamic cerebral autoregulation to spontaneous fluctuations in blood pressure is enhanced following lipopolysaccharide (LPS) infusion, a human experimental model of early sepsis, whereas by contrast it is impaired in patients with severe sepsis or septic shock. In this study, we hypothesized that this pattern of response would be identical during induced changes in blood pressure. Dynamic cerebral autoregulation was assessed in nine healthy volunteers and six septic patients. The healthy volunteers underwent a 4-h intravenous infusion of LPS (total dose: 2 ng kg-1 ). Mean arterial blood pressure (MAP, arterial transducer) and middle cerebral artery blood flow velocity (MCAv, transcranial Doppler ultrasound) were recorded continuously during thigh-cuff deflation-induced changes in MAP for the determination of a modified rate of regulation (RoR). This was performed before and after LPS infusion in healthy volunteers, and within 72 h following clinical diagnosis of sepsis in patients. In healthy volunteers, thigh-cuff deflation caused a MAP reduction of 16 (13-20) % at baseline and 18 (16-20) % after LPS, while the MAP reduction was 12 (11-13) % in patients (P<0·05 versus volunteers at baseline; P<0·01 versus volunteers after LPS). The corresponding RoR values increased from 0·46 (0·31-0·49) s-1 at baseline to 0·58 (0·36-0·74) s-1 after LPS (P<0·05) in healthy volunteers, whereas they were similar to values observed in patients [0·43 (0·36-0·52) s-1 ; P = 0·91 versus baseline; P = 0·14 versus LPS]. While our findings support the concept that dynamic cerebral autoregulation is enhanced during the very early stages of sepsis, they remain inconclusive with regard to more advanced stages of disease, because thigh-cuff deflation failed to induce sufficient MAP reductions in patients.
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Affiliation(s)
- Ronan M G Berg
- Department of Clinical Physiology, Nuclear Medicine & PET, University Hospital Rigshospitalet, Copenhagen Ø, Denmark. .,Centre of Inflammation and Metabolism, Department of Infectious Diseases M7641, University Hospital Rigshospitalet, Copenhagen Ø, Denmark.
| | - Ronni R Plovsing
- Department of Intensive Care, University Hospital Rigshospitalet, Copenhagen Ø, Denmark.,Department of Anaesthesia, Køge Hospital, Køge, Denmark
| | - Damian M Bailey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Wales, UK
| | - Niels-Henrik Holstein-Rathlou
- Renal and Vascular Research Section, Department of Biomedical Sciences, Faculty of Health Sciences, University of Copenhagen, Copenhagen Ø, Denmark
| | - Kirsten Møller
- Centre of Inflammation and Metabolism, Department of Infectious Diseases M7641, University Hospital Rigshospitalet, Copenhagen Ø, Denmark.,Neurointensive Care Unit 2093, Department of Neuroanaesthesiology, University Hospital Rigshospitalet, Copenhagen Ø, Denmark
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32
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Yang CH, Kao MC, Shih PC, Li KY, Tsai PS, Huang CJ. Simvastatin attenuates sepsis-induced blood-brain barrier integrity loss. J Surg Res 2015; 194:591-598. [DOI: 10.1016/j.jss.2014.11.030] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/13/2014] [Accepted: 11/20/2014] [Indexed: 01/04/2023]
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33
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34
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Toksvang LN, Plovsing RR, Petersen MW, Møller K, Berg RMG. Poor agreement between transcranial Doppler and near-infrared spectroscopy-based estimates of cerebral blood flow changes in sepsis. Clin Physiol Funct Imaging 2014; 34:405-9. [PMID: 24750661 DOI: 10.1111/cpf.12120] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Accepted: 11/25/2013] [Indexed: 11/28/2022]
Abstract
BACKGROUND Continuous monitoring of cerebral blood flow (CBF) may be valuable in critically ill patients with sepsis. In this study, we compared spatially resolved near-infrared spectroscopy (NIRS) to transcranial Doppler ultrasound (TCD)-derived estimates of noradrenaline-associated changes in CBF in such patients. METHODS Mean arterial blood pressure (MAP) was elevated by increasing the noradrenaline infusion rate in eight mechanically ventilated, critically ill patients diagnosed with severe sepsis or septic shock. The associated changes in CBF were assessed by simultaneous ipsilateral NIRS (ScO(2)) and TCD (middle cerebral artery blood flow velocity, MCAv) measurements. RESULTS A total of fifteen simultaneous NIRS- and TCD-derived assessments of noradrenaline-associated changes in CBF were obtained. MAP was increased from 74 (median; interquartile range (IQR), 71-90) to 100 (median; IQR, 93-115) mmHg (P<0·05), which was associated with an increase in MCAv of 14% (median; IQR, 2-22; P<0·05), whereas no changes were observed in ScO(2) ; 1% (median; IQR, [-4]-3; P = 0·96). A Bland-Altman plot was used to compare the two methods and showed a poor agreement between NIRS- and TCD-derived estimates with a relative bias of 14% and limits of agreement of -18% to 45% change in CBF. CONCLUSION Our findings stress that TCD and NIRS cannot be used interchangeably for monitoring changes in cerebral haemodynamics in critically ill patients with sepsis receiving vasopressor treatment with noradrenaline.
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Affiliation(s)
- Linea N Toksvang
- Centre of Inflammation and Metabolism, University Hospital Rigshospitalet, Copenhagen Ø, Denmark
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35
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Ainslie PN, Brassard P. Why is the neural control of cerebral autoregulation so controversial? F1000PRIME REPORTS 2014; 6:14. [PMID: 24669295 PMCID: PMC3944747 DOI: 10.12703/p6-14] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Cerebral autoregulation refers to the mechanisms that act to keep cerebral blood flow (CBF) constant during changes in blood pressure. The mechanisms of cerebral autoregulation, especially in humans, are poorly understood but are undoubtedly multifactorial and likely reflect many redundant pathways that potentially differ between species. Whether sympathetic nervous activity influences CBF and/or cerebral autoregulation in humans remains controversial. Following a brief introduction to cerebral autoregulation, this review highlights the likely reasons behind the controversy of the neural control of cerebral autoregulation. Finally, suggestions are provided for further studies to improve the understanding of the neural control of CBF regulation.
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Affiliation(s)
- Philip N. Ainslie
- Center for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia – OkanaganKelowna, British ColumbiaCanada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université LavalQuébecCanada
- Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de QuébecQuébecCanada
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Does the static cerebral autoregulatory plateau have a finite slope in healthy preterm neonates? Early Hum Dev 2014; 90:97-8. [PMID: 24365604 DOI: 10.1016/j.earlhumdev.2013.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Revised: 11/23/2013] [Accepted: 12/03/2013] [Indexed: 11/21/2022]
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Berg RMG, Plovsing RR, Evans KA, Christiansen CB, Bailey DM, Holstein-Rathlou NH, Møller K. Lipopolysaccharide infusion enhances dynamic cerebral autoregulation without affecting cerebral oxygen vasoreactivity in healthy volunteers. Crit Care 2013; 17:R238. [PMID: 24131656 PMCID: PMC4057209 DOI: 10.1186/cc13062] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 08/13/2013] [Indexed: 12/23/2022] Open
Abstract
INTRODUCTION Sepsis may be associated with disturbances in cerebral oxygen transport and cerebral haemodynamic function, thus rendering the brain particularly susceptible to hypoxia. The purpose of this study was to assess the impact of isocapnic hypoxia and hyperoxia on dynamic cerebral autoregulation in a human-experimental model of the systemic inflammatory response during the early stages of sepsis. METHODS A total of ten healthy volunteers were exposed to acute isocapnic inspiratory hyperoxia (FIO₂ = 40%) and hypoxia (FIO₂ = 12%) before and after a 4-hour lipopolysaccharide (LPS) infusion (2 ng kg-1). Middle cerebral artery blood follow velocity was assessed using transcranial Doppler ultrasound, and dynamic autoregulation was evaluated by transfer function analysis. RESULTS Transfer function analysis revealed an increase in the phase difference between mean arterial blood pressure and middle cerebral artery blood flow velocity in the low frequency range (0.07-0.20 Hz) after LPS (P<0.01). In contrast, there were no effects of either isocapnic hyperoxia or hypoxia on dynamic autoregulation, and the cerebral oxygen vasoreactivity to both hyperoxia and hypoxia was unaffected by LPS. CONCLUSIONS The observed increase in phase suggests that dynamic cerebral autoregulation is enhanced after LPS infusion and resistant to any effects of acute hypoxia; this may protect the brain from ischaemia and/or blood-brain barrier damage during the early stages of sepsis.
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Affiliation(s)
- Ronan MG Berg
- Centre of Inflammation and Metabolism, Department of Infectious Diseases, section M7641, University Hospital Rigshospitalet, Blegdamsvej 9, DK-2100, Copenhagen Ø, Denmark
- Renal and Vascular Research Section, Department of Biomedical Sciences, Faculty of Health Sciences, University of Copenhagen, Copenhagen N, Denmark
- Intensive Care Unit 4131, University Hospital Rigshospitalet, Copenhagen Ø, Denmark
| | - Ronni R Plovsing
- Intensive Care Unit 4131, University Hospital Rigshospitalet, Copenhagen Ø, Denmark
| | - Kevin A Evans
- Neurovascular Research Laboratory, Faculty of Health, Science and Sport, University of Glamorgan, South Wales CF374AT, UK
| | - Claus B Christiansen
- Centre of Inflammation and Metabolism, Department of Infectious Diseases, section M7641, University Hospital Rigshospitalet, Blegdamsvej 9, DK-2100, Copenhagen Ø, Denmark
| | - Damian M Bailey
- Neurovascular Research Laboratory, Faculty of Health, Science and Sport, University of Glamorgan, South Wales CF374AT, UK
| | - Niels-Henrik Holstein-Rathlou
- Renal and Vascular Research Section, Department of Biomedical Sciences, Faculty of Health Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Kirsten Møller
- Centre of Inflammation and Metabolism, Department of Infectious Diseases, section M7641, University Hospital Rigshospitalet, Blegdamsvej 9, DK-2100, Copenhagen Ø, Denmark
- Neurointensive Care Unit 2093, Department of Neuroanaesthesiology, University Hospital Rigshospitalet, Copenhagen Ø, Denmark
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Coagulopathy, catecholamines, and biomarkers of endothelial damage in experimental human endotoxemia and in patients with severe sepsis: A prospective study. J Crit Care 2013; 28:586-96. [DOI: 10.1016/j.jcrc.2013.04.010] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Revised: 03/24/2013] [Accepted: 04/21/2013] [Indexed: 02/01/2023]
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Ostrowski SR, Berg RMG, Windeløv NA, Meyer MAS, Plovsing RR, Møller K, Johansson PI. Discrepant fibrinolytic response in plasma and whole blood during experimental endotoxemia in healthy volunteers. PLoS One 2013; 8:e59368. [PMID: 23555024 PMCID: PMC3598702 DOI: 10.1371/journal.pone.0059368] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 02/13/2013] [Indexed: 01/07/2023] Open
Abstract
Background Sepsis induces early activation of coagulation and fibrinolysis followed by late fibrinolytic shutdown and progressive endothelial damage. The aim of the present study was to investigate and compare the functional hemostatic response in whole blood and plasma during experimental human endotoxemia by the platelet function analyzer, Multiplate and by standard and modified thrombelastography (TEG). Methods Prospective physiologic study of nine healthy male volunteers undergoing endotoxemia by means of a 4-hour infusion of E. coli lipopolysaccharide (LPS, 0.5 ng/kg/hour), with blood sampled at baseline and at 4 h and 6 h. Physiological and standard biochemical data and coagulation tests, TEG (whole blood: TEG, heparinase-TEG, Functional Fibrinogen; plasma: TEG±tissue-type plasminogen activator (tPA)) and Multiplate (TRAPtest, ADPtest, ASPItest, COLtest) were recorded. Mixed models with Tukey post hoc tests and correlations were applied. Results Endotoxemia induced acute SIRS with increased HR, temperature, WBC, CRP and procalcitonin and decreased blood pressure. It also induced a hemostatic response with platelet consumption and reduced APTT while INR increased (all p<0.05). Platelet aggregation decreased (all tests, p<0.05), whereas TEG whole blood clot firmness increased (G, p = 0.05). Furthermore, during endotoxemia (4 h), whole blood fibrinolysis increased (clot lysis time (CLT), p<0.001) and Functional Fibrinogen clot strength decreased (p = 0.049). After endotoxemia (6 h), whole blood fibrinolysis was reduced (CLT, p<0.05). In contrast to findings in whole blood, the plasma fibrin clot became progressively more resistant towards tPA-induced fibrinolysis at both 4 h and 6 h (p<0.001). Conclusions Endotoxemia induced a hemostatic response with reduced primary but enhanced secondary hemostasis, enhanced early fibrinolysis and fibrinogen consumption followed by downregulation of fibrinolysis, with a discrepant fibrinolytic response in plasma and whole blood. The finding that blood cells are critically involved in the vasculo-fibrinolytic response to acute inflammation is important given that disturbances in the vascular system contribute significantly to morbidity and mortality in critically ill patients.
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Affiliation(s)
- Sisse R Ostrowski
- Section for Transfusion Medicine, Capital Region Blood Bank, Rigshospitalet, Copenhagen, Denmark.
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