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Lang SS, Rahman R, Kumar N, Tucker A, Flanders TM, Kirschen M, Huh JW. Invasive Neuromonitoring Modalities in the Pediatric Population. Neurocrit Care 2023; 38:470-485. [PMID: 36890340 DOI: 10.1007/s12028-023-01684-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 01/30/2023] [Indexed: 03/10/2023]
Abstract
Invasive neuromonitoring has become an important part of pediatric neurocritical care, as neuromonitoring devices provide objective data that can guide patient management in real time. New modalities continue to emerge, allowing clinicians to integrate data that reflect different aspects of cerebral function to optimize patient management. Currently, available common invasive neuromonitoring devices that have been studied in the pediatric population include the intracranial pressure monitor, brain tissue oxygenation monitor, jugular venous oximetry, cerebral microdialysis, and thermal diffusion flowmetry. In this review, we describe these neuromonitoring technologies, including their mechanisms of function, indications for use, advantages and disadvantages, and efficacy, in pediatric neurocritical care settings with respect to patient outcomes.
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Affiliation(s)
- Shih-Shan Lang
- Division of Neurosurgery, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, 6 Wood Center, Philadelphia, PA, 19104, USA. .,Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Raphia Rahman
- Division of Neurosurgery, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, 6 Wood Center, Philadelphia, PA, 19104, USA.,School of Osteopathic Medicine, Rowan University, Stratford, NJ, USA
| | - Nankee Kumar
- Division of Neurosurgery, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, 6 Wood Center, Philadelphia, PA, 19104, USA
| | - Alexander Tucker
- Division of Neurosurgery, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, 6 Wood Center, Philadelphia, PA, 19104, USA
| | - Tracy M Flanders
- Division of Neurosurgery, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, 6 Wood Center, Philadelphia, PA, 19104, USA
| | - Matthew Kirschen
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia and Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jimmy W Huh
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia and Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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2
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Sharma R, Tsikvadze M, Peel J, Howard L, Kapoor N, Freeman WD. Multimodal monitoring: practical recommendations (dos and don'ts) in challenging situations and uncertainty. Front Neurol 2023; 14:1135406. [PMID: 37206910 PMCID: PMC10188941 DOI: 10.3389/fneur.2023.1135406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 04/06/2023] [Indexed: 05/21/2023] Open
Abstract
With the advancements in modern medicine, new methods are being developed to monitor patients in the intensive care unit. Different modalities evaluate different aspects of the patient's physiology and clinical status. The complexity of these modalities often restricts their use to the realm of clinical research, thereby limiting their use in the real world. Understanding their salient features and their limitations can aid physicians in interpreting the concomitant information provided by multiple modalities to make informed decisions that may affect clinical care and outcomes. Here, we present a review of the commonly used methods in the neurological intensive care unit with practical recommendations for their use.
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Affiliation(s)
- Rohan Sharma
- Department of Neurology, Mayo Clinic in Florida, Jacksonville, FL, United States
- *Correspondence: Rohan Sharma
| | - Mariam Tsikvadze
- Department of Neurology, Mayo Clinic in Florida, Jacksonville, FL, United States
| | - Jeffrey Peel
- Department of Neurology, Mayo Clinic in Florida, Jacksonville, FL, United States
| | - Levi Howard
- Department of Neurology, Mayo Clinic in Florida, Jacksonville, FL, United States
| | - Nidhi Kapoor
- Department of Neurology, Baptist Medical Center, Jacksonville, FL, United States
| | - William D. Freeman
- Department of Neurology, Mayo Clinic in Florida, Jacksonville, FL, United States
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3
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Sarigul B, De Macêdo Filho LJM, Hawryluk GWJ. Invasive Monitoring in Traumatic Brain Injury. CURRENT SURGERY REPORTS 2022. [DOI: 10.1007/s40137-022-00332-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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4
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Wang T, Kleiven S, Li X. Electroosmosis Based Novel Treatment Approach for Cerebral Edema. IEEE Trans Biomed Eng 2021; 68:2645-2653. [PMID: 33338011 DOI: 10.1109/tbme.2020.3045916] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Cerebral edema characterized as an abnormal accumulation of interstitial fluid has not been treated effectively. We propose a novel edema treatment approach to drive edematous fluid out of the brain by direct current utilizing brain tissue's electroosmotic property. METHODS A finite element (FE) head model is developed and employed to assess the feasibility of the approach. First, the capacity of the model for electric field prediction is validated against human experiments. Second, two electrode configurations (S and D-montage) are designed to evaluate the distribution of the electric field, electroosmotic flow (EOF), current density, and temperature across the brain under an applied direct current. RESULTS The S-montage is shown to induce an average EOF velocity of 7e-4 mm/s underneath the anode by a voltage of 15 V, and the D-montage induces a velocity of 9e-4 mm/s by a voltage of 5 V. Meanwhile, the brain temperature in both configurations is below 38 °C, which is within the safety range. Further, the magnitude of EOF is proportional to the electric field, and the EOF direction follows the current flow from anode to cathode. The EOF velocity in the white matter is significantly higher than that in the gray matter under the anode where the fluid is to be drawn out. CONCLUSION The proposed electroosmosis based approach allows alleviating brain edema within the critical time window by direct current. SIGNIFICANCE The approach may be further developed as a new treatment solely or as a complement to existing conventional treatments of edema.
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Hoiland RL, Ainslie PN, Wellington CL, Cooper J, Stukas S, Thiara S, Foster D, Fergusson N, Conway EM, Menon DK, Gooderham PA, Hirsch-Reinshagen V, Griesdale D, Sekhon M. Brain Hypoxia Is Associated With Neuroglial Injury in Humans Post-Cardiac Arrest. Circ Res 2021; 129:583-597. [PMID: 34287000 PMCID: PMC8376277 DOI: 10.1161/circresaha.121.319157] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Supplemental Digital Content is available in the text. Secondary brain hypoxia portends significant mortality in ischemic brain diseases; yet, our understanding of hypoxic ischemic brain injury (HIBI) pathophysiology in humans remains rudimentary.
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Affiliation(s)
- Ryan L Hoiland
- Health and Exercise Sciences, University of British Columbia Okanagan, CANADA
| | | | | | | | - Sophie Stukas
- Pathology and Laboratory Medicine, University of British Columbia, CANADA
| | - Sonny Thiara
- Critical Care Medicine, University of British Columbia
| | - Denise Foster
- Critical Care Medicine, University of British Columbia, CANADA
| | | | - Edward M Conway
- Centre for Blood Research, University of British Columbia, CANADA
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6
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Lüchow M, Fortuin L, Malkoch M. Modular, synthetic, thiol‐ene mediated hydrogel networks as potential scaffolds for
3D
cell cultures and tissue regeneration. JOURNAL OF POLYMER SCIENCE 2020. [DOI: 10.1002/pol.20200530] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Mads Lüchow
- Division of Coating Technology, Department of Fibre and Polymer Technology KTH Stockholm Sweden
| | - Lisa Fortuin
- Division of Coating Technology, Department of Fibre and Polymer Technology KTH Stockholm Sweden
| | - Michael Malkoch
- Division of Coating Technology, Department of Fibre and Polymer Technology KTH Stockholm Sweden
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7
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Beck-Schimmer B, Restin T, Muroi C, Roth Z'Graggen B, Keller E, Schläpfer M. Sevoflurane sedation attenuates early cerebral oedema formation through stabilisation of the adherens junction protein beta catenin in a model of subarachnoid haemorrhage: A randomised animal study. Eur J Anaesthesiol 2020; 37:402-412. [PMID: 32068571 DOI: 10.1097/eja.0000000000001161] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Severe neurological impairment is a problem after subarachnoid haemorrhage (SAH). Although volatile anaesthetics, such as sevoflurane, have demonstrated protective properties in many organs, their use in cerebral injury is controversial. Cerebral vasodilation may lead to increased intracranial pressure (ICP), but at the same time volatile anaesthetics are known to stabilise the SAH-injured endothelial barrier. OBJECTIVE To test the effect of sevoflurane on ICP and blood-brain barrier function. DESIGN Randomised study. PARTICIPANTS One hundred male Wistar rats included, 96 analysed. INTERVENTIONS SAH was induced by the endoluminal filament method under ketamine/xylazine anaesthesia. Fifteen minutes after sham surgery or induction of SAH, adult male Wistar rats were randomised to 4 h sedation with either propofol or sevoflurane. MAIN OUTCOME MEASURES Mean arterial pressure (MAP), ICP, extravasation of water (small), Evan's blue (intermediate) and IgG (large molecule) were measured. Zonula occludens-1 (ZO-1) and beta-catenin (β-catenin), as important representatives of tight and adherens junction proteins, were determined by western blot. RESULTS Propofol and sevoflurane sedation did not affect MAP or ICP in SAH animals. Extravasation of small molecules was higher in SAH-propofol compared with SAH-sevoflurane animals (79.1 ± 0.9 vs. 78.0 ± 0.7%, P = 0.04). For intermediate and large molecules, no difference was detected (P = 0.6 and P = 0.2). Both membrane and cytosolic fractions of ZO-1 as well as membrane β-catenin remained unaffected by the injury and type of sedation. Decreased cytosolic fraction of β-catenin in propofol-SAH animals (59 ± 15%) was found to reach values of sham animals (100%) in the presence of sevoflurane in SAH animals (89 ± 21%; P = 0.04). CONCLUSION This experiment demonstrates that low-dose short-term sevoflurane sedation after SAH in vivo did not affect ICP and MAP and at the same time may attenuate early brain oedema formation, potentially by preserving adherens junctions. TRIAL REGISTRATION No 115/2014 Veterinäramt Zürich.
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Affiliation(s)
- Beatrice Beck-Schimmer
- From the Institute of Physiology and Zurich Centre for Integrative Human Physiology, University of Zurich (BBS, TR, BRZ, MS), Institute of Anaesthesiology, University Hospital Zurich, Zurich, Switzerland (BBS, TR, MS), Department of Anesthesiology, University of Illinois at Chicago, Chicago, USA (BBS) and Neurosurgical Intensive Care Unit, University Hospital Zurich, Zurich, Switzerland (CM, EK)
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8
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Oros-Peusquens AM, Loução R, Abbas Z, Gras V, Zimmermann M, Shah NJ. A Single-Scan, Rapid Whole-Brain Protocol for Quantitative Water Content Mapping With Neurobiological Implications. Front Neurol 2019; 10:1333. [PMID: 31920951 PMCID: PMC6934004 DOI: 10.3389/fneur.2019.01333] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 12/02/2019] [Indexed: 12/16/2022] Open
Abstract
Water concentration is tightly regulated in the healthy human brain and changes only slightly with age and gender in healthy subjects. Consequently, changes in water content are important for the characterization of disease. MRI can be used to measure changes in brain water content, but as these changes are usually in the low percentage range, highly accurate and precise methods are required for detection. The method proposed here is based on a long-TR (10 s) multiple-echo gradient-echo measurement with an acquisition time of 7:21 min. Using such a long TR ensures that there is no T1 weighting, meaning that the image intensity at zero echo time is only proportional to the water content, the transmit field, and to the receive field. The receive and transmit corrections, which are increasingly large at higher field strengths and for highly segmented coil arrays, are multiplicative and can be approached heuristically using a bias field correction. The method was tested on 21 healthy volunteers at 3T field strength. Calibration using cerebral-spinal fluid values (~100% water content) resulted in mean values and standard deviations of the water content distribution in white matter and gray matter of 69.1% (1.7%) and 83.7% (1.2%), respectively. Measured distributions were coil-independent, as seen by using either a 12-channel receiver coil or a 32-channel receiver coil. In a test-retest investigation using 12 scans on one volunteer, the variation in the mean value of water content for different tissue types was ~0.3% and the mean voxel variability was ~1%. Robustness against reduced SNR was assessed by comparing results for 5 additional volunteers at 1.5T and 3T. Furthermore, water content distribution in gray matter is investigated and regional contrast reported for the first time. Clinical applicability is illustrated with data from one stroke patient and one brain tumor patient. It is anticipated that this fast, stable, easy-to-use, high-quality mapping method will facilitate routine quantitative MR imaging of water content.
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Affiliation(s)
| | - Ricardo Loução
- Institute of Neurosciences and Medicine 4 (INM-4), Forschungszentrum Jülich, Jülich, Germany
| | - Zaheer Abbas
- Institute of Neurosciences and Medicine 4 (INM-4), Forschungszentrum Jülich, Jülich, Germany
| | - Vincent Gras
- Institute of Neurosciences and Medicine 4 (INM-4), Forschungszentrum Jülich, Jülich, Germany
| | - Markus Zimmermann
- Institute of Neurosciences and Medicine 4 (INM-4), Forschungszentrum Jülich, Jülich, Germany
| | - N J Shah
- Institute of Neurosciences and Medicine 4 (INM-4), Forschungszentrum Jülich, Jülich, Germany.,Institute of Neurosciences and Medicine 11 (INM-11), JARA, Forschungszentrum Jülich, Jülich, Germany.,JARA - BRAIN - Translational Medicine, Aachen, Germany.,Department of Neurology, RWTH Aachen University, Aachen, Germany
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9
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Kundu B, Awad AW, Park MS, Grandhi R, Enniss T, Hawryluk GWJ. Characterization of Focal Brain Tissue Water Measurements in Human Traumatic Brain Injury. World Neurosurg 2019; 135:e271-e285. [PMID: 31805402 DOI: 10.1016/j.wneu.2019.11.132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 11/21/2019] [Accepted: 11/22/2019] [Indexed: 10/25/2022]
Abstract
BACKGROUND Cerebral edema is a major cause of morbidity in patients with severe traumatic brain injury (TBI). Intraparenchymal thermal conductivity-based probes that measure local cerebral blood flow can measure percent brain tissue water (%BTW) content, but such measures have been insufficiently characterized in patients with TBI. METHODS We retrospectively reviewed physiologic data from patients with severe TBI treated at our institution (2014-2016) who underwent cerebral blood flow monitoring. RESULTS Sixteen patients underwent focal %BTW measurements at a 15-minute sampling rate. %BTW measurements showed characteristic temporal profiles, with a mean time to peak of 3.7 ± 1.7 days. The mean minimum and maximum %BTWs were 71.0 ± 3.9% and 82.7 ± 7.4%, respectively (overall mean %BTW, 77.0 ± 2.9%). Intracranial pressure (ICP) values of 22 mm Hg (the current treatment threshold for patients with trauma) corresponded to 75.8 ± 5.4 %BTW. Repeated measures correlation showed that %BTW is negatively correlated with serum sodium concentration (r = -0.3; P < 0.001) and weakly positively correlated with ICP (r = 0.08; P = 0.01) and regional cerebral blood flow (r = 0.06; P < 0.001). These effects were consistent in a multivariable model including time from injury. In the best model, time was modeled as a quadratic term because the %BTW followed a parabolic trajectory. CONCLUSIONS %BTW may be a clinically useful, real-time measurement of cerebral edema in patients with TBI. It is closely associated with the serum sodium concentration and follows a characteristic temporal course with characteristic trajectory and stability over time.
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Affiliation(s)
- Bornali Kundu
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah, USA
| | - Al-Wala Awad
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah, USA
| | - Min S Park
- Department of Neurosurgery, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Ramesh Grandhi
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah, USA
| | - Toby Enniss
- Department of Surgery, University of Utah, Salt Lake City, Utah, USA
| | - Gregory W J Hawryluk
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah, USA; Section of Neurosurgery, University of Manitoba, Winnipeg, Manitoba, Canada.
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10
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Cerebral Edema After Cardiopulmonary Resuscitation: A Therapeutic Target Following Cardiac Arrest? Neurocrit Care 2019; 28:276-287. [PMID: 29080068 DOI: 10.1007/s12028-017-0474-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We sought to review the role that cerebral edema plays in neurologic outcome following cardiac arrest, to understand whether cerebral edema might be an appropriate therapeutic target for neuroprotection in patients who survive cardiopulmonary resuscitation. Articles indexed in PubMed and written in English. Following cardiac arrest, cerebral edema is a cardinal feature of brain injury and is a powerful prognosticator of neurologic outcome. Like other conditions characterized by cerebral ischemia/reperfusion, neuroprotection after cardiac arrest has proven to be difficult to achieve. Neuroprotection after cardiac arrest generally has focused on protecting neurons, not the microvascular endothelium or blood-brain barrier. Limited preclinical data suggest that strategies to reduce cerebral edema may improve neurologic outcome. Ongoing research will be necessary to determine whether targeting cerebral edema will improve patient outcomes after cardiac arrest.
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11
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Sinha S, Hudgins E, Schuster J, Balu R. Unraveling the complexities of invasive multimodality neuromonitoring. Neurosurg Focus 2018; 43:E4. [PMID: 29088949 DOI: 10.3171/2017.8.focus17449] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Acute brain injuries are a major cause of death and disability worldwide. Survivors of life-threatening brain injury often face a lifetime of dependent care, and novel approaches that improve outcome are sorely needed. A delayed cascade of brain damage, termed secondary injury, occurs hours to days and even weeks after the initial insult. This delayed phase of injury provides a crucial window for therapeutic interventions that could limit brain damage and improve outcome. A major barrier in the ability to prevent and treat secondary injury is that physicians are often unable to target therapies to patients' unique cerebral physiological disruptions. Invasive neuromonitoring with multiple complementary physiological monitors can provide useful information to enable this tailored, precision approach to care. However, integrating the multiple streams of time-varying data is challenging and often not possible during routine bedside assessment. The authors review and discuss the principles and evidence underlying several widely used invasive neuromonitors. They also provide a framework for integrating data for clinical decision making and discuss future developments in informatics that may allow new treatment paradigms to be developed.
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Affiliation(s)
- Saurabh Sinha
- Department of Neurosurgery, Perelman School of Medicine; and
| | - Eric Hudgins
- Department of Neurosurgery, Perelman School of Medicine; and
| | - James Schuster
- Department of Neurosurgery, Perelman School of Medicine; and
| | - Ramani Balu
- Department of Neurology, Division of Neurocritical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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12
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Kofler M, Schiefecker A, Beer R, Sohm F, Broessner G, Rhomberg P, Lackner P, Pfausler B, Thomé C, Schmutzhard E, Helbok R. Neuroglucopenia and Metabolic Distress in Two Patients with Viral Meningoencephalitis: A Microdialysis Study. Neurocrit Care 2017; 25:273-81. [PMID: 27112148 PMCID: PMC5043006 DOI: 10.1007/s12028-016-0272-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Introduction Viral encephalitis is an emerging disease requiring intensive care management in severe cases. Underlying pathophysiologic mechanisms are incompletely understood and may be elucidated using invasive multimodal neuromonitoring techniques in humans. Methods Two otherwise healthy patients were admitted to our neurological intensive care unit with altered level of consciousness necessitating mechanical ventilation. Brain imaging and laboratory workup suggested viral encephalitis in both patients. Invasive neuromonitoring was initiated when head computed tomography revealed generalized brain edema, including monitoring of intracranial pressure, brain metabolism (cerebral microdialysis; CMD), brain tissue oxygen tension (in one patient), and cerebral blood flow (in one patient). Results Brain metabolism revealed episodes of severe neuroglucopenia (brain glucose <0.7 mM/l) in both patients, which were not attributable to decreased cerebral perfusion or hypoglycemia. CMD-glucose levels changed depending on variations in insulin therapy, nutrition, and systemic glucose administration. The metabolic profile, moreover, showed a pattern of non-ischemic metabolic distress suggestive for mitochondrial dysfunction. Both patients had a prolonged but favorable clinical course and improved to a modified Rankin Scale Score of 1 and 0 three months later. Conclusion Invasive multimodal neuromonitoring is feasible in poor-grade patients with viral meningoencephalitis and may help understand pathophysiologic mechanisms associated with secondary brain injury. The detection of neuroglucopenia and mitochondrial dysfunction may serve as treatment targets in the future.
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Affiliation(s)
- Mario Kofler
- Neurological Intensive Care Unit, Department of Neurology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Alois Schiefecker
- Neurological Intensive Care Unit, Department of Neurology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Ronny Beer
- Neurological Intensive Care Unit, Department of Neurology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Florian Sohm
- Department of Neurosurgery, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Gregor Broessner
- Neurological Intensive Care Unit, Department of Neurology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Paul Rhomberg
- Department of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Peter Lackner
- Neurological Intensive Care Unit, Department of Neurology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Bettina Pfausler
- Neurological Intensive Care Unit, Department of Neurology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Claudius Thomé
- Department of Neurosurgery, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Erich Schmutzhard
- Neurological Intensive Care Unit, Department of Neurology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Raimund Helbok
- Neurological Intensive Care Unit, Department of Neurology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria.
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Abstract
Management of patients with aneurysmal subarachnoid hemorrhage focuses on prevention of rebleeding by early treatment of the aneurysm, as well as detection and management of neurologic and medical complications. Early detection of delayed cerebral ischemia and management of modifiable contributing causes such as vasospasm take a central role, with the goal of preventing irreversible cerebral injury. In efforts to prevent delayed cerebral ischemia, multimodality monitoring has emerged as a promising tool in detecting subclinical physiologic changes before infarction occurs. However, there has been much variability in the utilization of this technology. Recent consensus guidelines discuss the role of multimodality monitoring in acute brain injury. In this review, we evaluate these guidelines and the utility of each modality of multimodality monitoring in aneurysmal subarachnoid hemorrhage.
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14
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Hirzallah MI, Choi HA. The Monitoring of Brain Edema and Intracranial Hypertension. JOURNAL OF NEUROCRITICAL CARE 2016. [DOI: 10.18700/jnc.160093] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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15
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Regional cerebral blood flow and cellular environment in subarachnoid hemorrhage: A thermal doppler flowmetry and microdialysis study. Neurol Neurochir Pol 2016; 51:66-71. [PMID: 27908617 DOI: 10.1016/j.pjnns.2016.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Revised: 08/19/2016] [Accepted: 11/09/2016] [Indexed: 11/20/2022]
Abstract
BACKGROUND Cerebral microdialysis enables assessment of regional metabolic physiology and provides biomarkers for clinical correlation in critical conditions, such as subarachnoid hemorrhage (SAH). The aim of our current study was to investigate the correlation between regional cerebral blood flow and microdialysis parameters (glucose, lactate, glycerol, pyruvate concentrations, and lactate/pyruvate metabolic ratio) in patients with SAH. MATERIALS AND METHODS Twenty-one patients with SAH were enrolled in our retrospective study. Cerebral blood flow (CBF) based on thermal diffusion methodology, the thermal coefficient K, and microdialysis biochemical markers were recorded. The duration of the brain monitoring was 10 days. RESULTS Microdialysis glucose concentration was inversely related to the cerebral temperature and to the L/P ratio. Furthermore, it was positively correlated to all other microdialysis parameters but glycerol. The K coefficient was strongly and positively correlated with the temperature and marginally with the CBF. The L/P ratio was positively correlated with glycerol, while it was inversely correlated with the CBF. Patients who died had elevated L/P ratio and K coefficient compared to the survivors in our series. CONCLUSIONS Thermal conductivity coefficient may change over time as cerebral injury progresses and tissue properties alter. These alterations were found to be associated with the microdialysis metabolite concentrations and the CBF itself. The microdialysis biochemical indices of cell stress and death (glycerol, L/P ratio) were positively related to each other, while the measured L/P metabolic ratio was higher among patients who died.
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Gradisek P, Dolenc S. Isoflurane rescue therapy for bronchospasm reduces intracranial pressure in a patient with traumatic brain injury. Brain Inj 2016; 30:1035-40. [PMID: 27120554 DOI: 10.3109/02699052.2016.1147598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PRIMARY OBJECTIVE To assess the unusual use of a volatile anaesthetic for treatment of life-threatening bronchospasm in a patient with traumatic brain injury (TBI). RESEARCH DESIGN Case report. METHODS AND PROCEDURES This study presents a previously healthy 30-year-old man with severe TBI and bronchospasm-induced acute hypercapnia. He was treated with inhaled isoflurane in combination with monitoring of intracranial pressure (ICP) and regional cerebral blood flow (rCBF). RESULTS Three-day-long isoflurane treatment resolved drug-refractory bronchospasm, decreased airway pressure and improved gas exchange, even at a low end-tidal concentration (0.3-0.5 vol%). Although rCBF was increased by 18 ml min(-1) 100 g(-1) during isoflurane treatment, there was a significant decrease in ICP (21 (SD = 3) mmHg, 9 (SD = 5) mmHg, 2 (SD = 3) mmHg; during pre-treatment, treatment and post-treatment, respectively; p < 0.001). Improved autoregulation due to lower partial pressure of carbon dioxide, restoration of carbon dioxide reactivity, isoflurane-induced regional differences in rCBF and improved microcirculation may have been responsible for the prompt and long-lasting normalization of ICP. The patient had no TBI-related disability at 6 months post-injury. CONCLUSIONS Isoflurane at a low dose can be an effective and safe treatment option for drug-refractory bronchospasm in a patient with traumatic intracranial hypertension, provided that multimodality neuromonitoring is used.
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Affiliation(s)
- Primoz Gradisek
- a Clinical Department of Anaesthesiology and Intensive Therapy , Centre for Intensive Therapy, University Medical Centre Ljubljana , Ljubljana , Slovenia
| | - Simon Dolenc
- a Clinical Department of Anaesthesiology and Intensive Therapy , Centre for Intensive Therapy, University Medical Centre Ljubljana , Ljubljana , Slovenia
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Claassen J, Rahman SA, Huang Y, Frey HP, Schmidt JM, Albers D, Falo CM, Park S, Agarwal S, Connolly ES, Kleinberg S. Causal Structure of Brain Physiology after Brain Injury from Subarachnoid Hemorrhage. PLoS One 2016; 11:e0149878. [PMID: 27123582 PMCID: PMC4849773 DOI: 10.1371/journal.pone.0149878] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 02/06/2016] [Indexed: 11/19/2022] Open
Abstract
High frequency physiologic data are routinely generated for intensive care patients. While massive amounts of data make it difficult for clinicians to extract meaningful signals, these data could provide insight into the state of critically ill patients and guide interventions. We develop uniquely customized computational methods to uncover the causal structure within systemic and brain physiologic measures recorded in a neurological intensive care unit after subarachnoid hemorrhage. While the data have many missing values, poor signal-to-noise ratio, and are composed from a heterogeneous patient population, our advanced imputation and causal inference techniques enable physiologic models to be learned for individuals. Our analyses confirm that complex physiologic relationships including demand and supply of oxygen underlie brain oxygen measurements and that mechanisms for brain swelling early after injury may differ from those that develop in a delayed fashion. These inference methods will enable wider use of ICU data to understand patient physiology.
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Affiliation(s)
- Jan Claassen
- Division of Critical Care Neurology, Department of Neurology, Columbia University, New York, NY, United States of America
- * E-mail:
| | - Shah Atiqur Rahman
- Computer Science Department, Stevens Institute of Technology, Hoboken, NJ, United States of America
| | - Yuxiao Huang
- Computer Science Department, Stevens Institute of Technology, Hoboken, NJ, United States of America
| | - Hans-Peter Frey
- Division of Critical Care Neurology, Department of Neurology, Columbia University, New York, NY, United States of America
| | - J. Michael Schmidt
- Division of Critical Care Neurology, Department of Neurology, Columbia University, New York, NY, United States of America
| | - David Albers
- Department of Biomedical Informatics, Columbia University, New York, NY, United States of America
| | - Cristina Maria Falo
- Division of Critical Care Neurology, Department of Neurology, Columbia University, New York, NY, United States of America
| | - Soojin Park
- Division of Critical Care Neurology, Department of Neurology, Columbia University, New York, NY, United States of America
| | - Sachin Agarwal
- Division of Critical Care Neurology, Department of Neurology, Columbia University, New York, NY, United States of America
| | - E. Sander Connolly
- Department of Neurosurgery, Columbia University, New York, NY, United States of America
| | - Samantha Kleinberg
- Computer Science Department, Stevens Institute of Technology, Hoboken, NJ, United States of America
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23.4% Saline Decreases Brain Tissue Volume in Severe Hepatic Encephalopathy as Assessed by a Quantitative CT Marker. Crit Care Med 2016; 44:171-9. [PMID: 26308431 DOI: 10.1097/ccm.0000000000001276] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Cerebral edema is common in severe hepatic encephalopathy and may be life threatening. Bolus 23.4% hypertonic saline improves surveillance neuromonitoring scores, although its mechanism of action is not clearly established. We investigated the hypothesis that bolus hypertonic saline decreases cerebral edema in severe hepatic encephalopathy utilizing a quantitative technique to measure brain and cerebrospinal fluid volume changes. DESIGN Retrospective analysis of serial CT scans, and clinical data for a case-control series were performed. SETTING ICUs of a tertiary care hospital. PATIENTS Patients with severe hepatic encephalopathy treated with 23.4% hypertonic saline and control patients who did not receive 23.4% hypertonic saline. INTERVENTIONS 23.4% hypertonic saline bolus administration. MEASUREMENTS AND MAIN RESULTS We used clinically obtained CT scans to measure volumes of the ventricles, intracranial cerebrospinal fluid, and brain using a previously validated semiautomated technique (Analyze Direct, Overland Park, KS). Volumes before and after 23.4% hypertonic saline were compared with Wilcoxon signed rank test. Associations among total cerebrospinal fluid volume, ventricular volume, serum sodium, and Glasgow Coma Scale scores were assessed using Spearman rank correlation test. Eleven patients with 18 administrations of 23.4% hypertonic saline met inclusion criteria. Total cerebrospinal fluid (median, 47.6 mL [35.1-69.4 mL] to 61.9 mL [47.7-87.0 mL]; p < 0.001) and ventricular volumes (median, 8.0 mL [6.9-9.5 mL] to 9.2 mL [7.8-11.9 mL]; p = 0.002) increased and Glasgow Coma Scale scores improved (median, 4 [3-6] to 7 [6-9]; p = 0.008) after 23.4% hypertonic saline. In contrast, total cerebrospinal fluid and ventricular volumes decreased in untreated control patients. Serum sodium increase was associated with increase in total cerebrospinal fluid volume (r = 0.83, p < 0.001), and change in total cerebrospinal fluid volume was associated with ventricular volume change (r = 0.86; p < 0.001). CONCLUSIONS Total cerebrospinal fluid and ventricular volumes increased after 23.4% hypertonic saline, consistent with a reduction in brain tissue volume. Total cerebrospinal fluid and ventricular volume change may be useful quantitative measures to assess cerebral edema in severe hepatic encephalopathy.
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Siler DA, Berlow YA, Kukino A, Davis CM, Nelson JW, Grafe MR, Ono H, Cetas JS, Pike M, Alkayed NJ. Soluble Epoxide Hydrolase in Hydrocephalus, Cerebral Edema, and Vascular Inflammation After Subarachnoid Hemorrhage. Stroke 2015; 46:1916-22. [PMID: 25991416 DOI: 10.1161/strokeaha.114.008560] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 04/23/2015] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND PURPOSE Acute communicating hydrocephalus and cerebral edema are common and serious complications of subarachnoid hemorrhage (SAH), whose causes are poorly understood. Using a mouse model of SAH, we determined whether soluble epoxide hydrolase (sEH) gene deletion protects against SAH-induced hydrocephalus and edema by increasing levels of vasoprotective eicosanoids and suppressing vascular inflammation. METHODS SAH was induced via endovascular puncture in wild-type and sEH knockout mice. Hydrocephalus and tissue edema were assessed by T2-weighted magnetic resonance imaging. Endothelial activation was assessed in vivo using T2*-weighted magnetic resonance imaging after intravenous administration of iron oxide particles linked to anti-vascular cell adhesion molecule-1 antibody 24 hours after SAH. Behavioral outcome was assessed at 96 hours after SAH with the open field and accelerated rotarod tests. RESULTS SAH induced an acute sustained communicating hydrocephalus within 6 hours of endovascular puncture in both wild-type and sEH knockout mice. This was followed by tissue edema, which peaked at 24 hours after SAH and was limited to white matter fiber tracts. sEH knockout mice had reduced edema, less vascular cell adhesion molecule-1 uptake, and improved outcome compared with wild-type mice. CONCLUSIONS Genetic deletion of sEH reduces vascular inflammation and edema and improves outcome after SAH. sEH inhibition may serve as a novel therapy for SAH.
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Affiliation(s)
- Dominic A Siler
- From the Department of Anesthesiology and Perioperative Medicine, The Knight Cardiovascular Institute (D.A.S., C.M.D., J.W.N., M.R.G., N.J.A.), Department of Neurological Surgery (D.A.S., J.S.C.), Advanced Imaging Research Center (Y.A.B., A.K., M.P.), Oregon Health and Science University, Portland; Department of Neurosurgery, Nishijima Hospital, Numazu City, Sizuoka, Japan (H.O.); and Portland VA Medical Center, OR (J.S.C.)
| | - Yosef A Berlow
- From the Department of Anesthesiology and Perioperative Medicine, The Knight Cardiovascular Institute (D.A.S., C.M.D., J.W.N., M.R.G., N.J.A.), Department of Neurological Surgery (D.A.S., J.S.C.), Advanced Imaging Research Center (Y.A.B., A.K., M.P.), Oregon Health and Science University, Portland; Department of Neurosurgery, Nishijima Hospital, Numazu City, Sizuoka, Japan (H.O.); and Portland VA Medical Center, OR (J.S.C.)
| | - Ayaka Kukino
- From the Department of Anesthesiology and Perioperative Medicine, The Knight Cardiovascular Institute (D.A.S., C.M.D., J.W.N., M.R.G., N.J.A.), Department of Neurological Surgery (D.A.S., J.S.C.), Advanced Imaging Research Center (Y.A.B., A.K., M.P.), Oregon Health and Science University, Portland; Department of Neurosurgery, Nishijima Hospital, Numazu City, Sizuoka, Japan (H.O.); and Portland VA Medical Center, OR (J.S.C.)
| | - Catherine M Davis
- From the Department of Anesthesiology and Perioperative Medicine, The Knight Cardiovascular Institute (D.A.S., C.M.D., J.W.N., M.R.G., N.J.A.), Department of Neurological Surgery (D.A.S., J.S.C.), Advanced Imaging Research Center (Y.A.B., A.K., M.P.), Oregon Health and Science University, Portland; Department of Neurosurgery, Nishijima Hospital, Numazu City, Sizuoka, Japan (H.O.); and Portland VA Medical Center, OR (J.S.C.)
| | - Jonathan W Nelson
- From the Department of Anesthesiology and Perioperative Medicine, The Knight Cardiovascular Institute (D.A.S., C.M.D., J.W.N., M.R.G., N.J.A.), Department of Neurological Surgery (D.A.S., J.S.C.), Advanced Imaging Research Center (Y.A.B., A.K., M.P.), Oregon Health and Science University, Portland; Department of Neurosurgery, Nishijima Hospital, Numazu City, Sizuoka, Japan (H.O.); and Portland VA Medical Center, OR (J.S.C.)
| | - Marjorie R Grafe
- From the Department of Anesthesiology and Perioperative Medicine, The Knight Cardiovascular Institute (D.A.S., C.M.D., J.W.N., M.R.G., N.J.A.), Department of Neurological Surgery (D.A.S., J.S.C.), Advanced Imaging Research Center (Y.A.B., A.K., M.P.), Oregon Health and Science University, Portland; Department of Neurosurgery, Nishijima Hospital, Numazu City, Sizuoka, Japan (H.O.); and Portland VA Medical Center, OR (J.S.C.)
| | - Hirohisa Ono
- From the Department of Anesthesiology and Perioperative Medicine, The Knight Cardiovascular Institute (D.A.S., C.M.D., J.W.N., M.R.G., N.J.A.), Department of Neurological Surgery (D.A.S., J.S.C.), Advanced Imaging Research Center (Y.A.B., A.K., M.P.), Oregon Health and Science University, Portland; Department of Neurosurgery, Nishijima Hospital, Numazu City, Sizuoka, Japan (H.O.); and Portland VA Medical Center, OR (J.S.C.)
| | - Justin S Cetas
- From the Department of Anesthesiology and Perioperative Medicine, The Knight Cardiovascular Institute (D.A.S., C.M.D., J.W.N., M.R.G., N.J.A.), Department of Neurological Surgery (D.A.S., J.S.C.), Advanced Imaging Research Center (Y.A.B., A.K., M.P.), Oregon Health and Science University, Portland; Department of Neurosurgery, Nishijima Hospital, Numazu City, Sizuoka, Japan (H.O.); and Portland VA Medical Center, OR (J.S.C.)
| | - Martin Pike
- From the Department of Anesthesiology and Perioperative Medicine, The Knight Cardiovascular Institute (D.A.S., C.M.D., J.W.N., M.R.G., N.J.A.), Department of Neurological Surgery (D.A.S., J.S.C.), Advanced Imaging Research Center (Y.A.B., A.K., M.P.), Oregon Health and Science University, Portland; Department of Neurosurgery, Nishijima Hospital, Numazu City, Sizuoka, Japan (H.O.); and Portland VA Medical Center, OR (J.S.C.)
| | - Nabil J Alkayed
- From the Department of Anesthesiology and Perioperative Medicine, The Knight Cardiovascular Institute (D.A.S., C.M.D., J.W.N., M.R.G., N.J.A.), Department of Neurological Surgery (D.A.S., J.S.C.), Advanced Imaging Research Center (Y.A.B., A.K., M.P.), Oregon Health and Science University, Portland; Department of Neurosurgery, Nishijima Hospital, Numazu City, Sizuoka, Japan (H.O.); and Portland VA Medical Center, OR (J.S.C.).
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Chen S, Feng H, Sherchan P, Klebe D, Zhao G, Sun X, Zhang J, Tang J, Zhang JH. Controversies and evolving new mechanisms in subarachnoid hemorrhage. Prog Neurobiol 2014; 115:64-91. [PMID: 24076160 PMCID: PMC3961493 DOI: 10.1016/j.pneurobio.2013.09.002] [Citation(s) in RCA: 270] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 09/07/2013] [Accepted: 09/12/2013] [Indexed: 12/13/2022]
Abstract
Despite decades of study, subarachnoid hemorrhage (SAH) continues to be a serious and significant health problem in the United States and worldwide. The mechanisms contributing to brain injury after SAH remain unclear. Traditionally, most in vivo research has heavily emphasized the basic mechanisms of SAH over the pathophysiological or morphological changes of delayed cerebral vasospasm after SAH. Unfortunately, the results of clinical trials based on this premise have mostly been disappointing, implicating some other pathophysiological factors, independent of vasospasm, as contributors to poor clinical outcomes. Delayed cerebral vasospasm is no longer the only culprit. In this review, we summarize recent data from both experimental and clinical studies of SAH and discuss the vast array of physiological dysfunctions following SAH that ultimately lead to cell death. Based on the progress in neurobiological understanding of SAH, the terms "early brain injury" and "delayed brain injury" are used according to the temporal progression of SAH-induced brain injury. Additionally, a new concept of the vasculo-neuronal-glia triad model for SAH study is highlighted and presents the challenges and opportunities of this model for future SAH applications.
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Affiliation(s)
- Sheng Chen
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China; Department of Physiology & Pharmacology, Loma Linda University, Loma Linda, CA, USA
| | - Hua Feng
- Department of Neurosurgery, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Prativa Sherchan
- Department of Physiology & Pharmacology, Loma Linda University, Loma Linda, CA, USA
| | - Damon Klebe
- Department of Physiology & Pharmacology, Loma Linda University, Loma Linda, CA, USA
| | - Gang Zhao
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shanxi, China
| | - Xiaochuan Sun
- Department of Neurosurgery, First Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Jianmin Zhang
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jiping Tang
- Department of Physiology & Pharmacology, Loma Linda University, Loma Linda, CA, USA
| | - John H Zhang
- Department of Physiology & Pharmacology, Loma Linda University, Loma Linda, CA, USA; Department of Neurosurgery, Loma Linda University, Loma Linda, CA, USA.
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Ko SB. Multimodality monitoring in the neurointensive care unit: a special perspective for patients with stroke. J Stroke 2013; 15:99-108. [PMID: 24324945 PMCID: PMC3779668 DOI: 10.5853/jos.2013.15.2.99] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2013] [Revised: 05/06/2013] [Accepted: 05/06/2013] [Indexed: 02/06/2023] Open
Abstract
Multimodality monitoring (MMM) is a recently developed method that aids in understanding real-time brain physiology. Early detection of physiological disturbances is possible with the help of MMM, which allows identification of underlying causes of deterioration and minimization of secondary brain injury (SBI). MMM is especially helpful in comatose patients with severe brain injury because neurological examinations are not sensitive enough to detect SBI. The variables frequently examined in MMM are hemodynamic parameters such as intracranial pressure, cerebral perfusion pressure, and mean arterial pressure; brainspecific oxygen tension; markers for brain metabolism including glucose, lactate, and pyruvate levels in brain tissue; and cerebral blood flow. Continuous electroencephalography can be performed, if needed. The majority of SBIs stem from brain tissue hypoxia, brain ischemia, and seizures, which lead to a disturbance in brain oxygen levels, cerebral blood flow, and electrical discharges, all of which are easily detected by MMM. In this review, we discuss the clinical importance of physiological variables as well as the practical applicability of MMM in patients with stroke.
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Affiliation(s)
- Sang-Bae Ko
- Department of Neurology, Seoul National University Hospital, Seoul, Korea
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