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Baron Shahaf D, Abergel E, Sivan Hoffmann R, Meirovitch E, Konstadt S, Feierman DE, Derman R, Shahaf G. Evaluating a Novel EEG-Based Index for Stroke Detection Under Anesthesia During Mechanical Thrombectomy. J Neurosurg Anesthesiol 2024; 36:60-68. [PMID: 36730962 DOI: 10.1097/ana.0000000000000889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 08/21/2022] [Indexed: 02/04/2023]
Abstract
BACKGROUND The rapid identification of acute stroke (AS) during and after anesthesia might lead to early interventions and improved outcomes. We investigated a novel 2-channel electroencephalogram (EEG)-based marker for stroke detection-the lateral interconnection ratio (LIR)-in AS patients having endovascular thrombectomy (EVT) with general anesthesia (GA) or sedation. The LIR in 2 reference groups of patients without postoperative neurological complications was used for comparison. METHODS The National Institutes of Health stroke scale score was assessed before and after thrombectomy in 100 patients having EVT with GA or sedation. The EEG was monitored during and for 4 hours following EVT in the AS group and during surgery in the 2 reference groups. We compared: (1) LIR between AS and reference groups; (2) LIR and stroke dynamics (clinical improvement or deterioration after EVT assessed by the National Institutes of Health stroke scale score); (3) the impact of stroke site (anterior vs. posterior circulation) and anesthesia type (GA vs. sedation) on the LIR. RESULTS Median (interquartile range) LIR was lower in patients with AS compared with reference patients (0.09, 0.05 to 0.16 vs. 0.39, 0.24 to 0.52, respectively; P <0.000002), and LIR increased in AS patients whose clinical status recovered after EVT compared with nonrecovered patients (0.20, 0.12 to 0.29 vs. 0.09, 0.05 to 0.11, respectively; P <0.007). The LIR might be more sensitive to anterior circulation stroke but is not impacted by anesthesia type. CONCLUSIONS We demonstrated the utility of using AS patients undergoing EVT as a platform for assessing a novel EEG marker for the identification of stroke during anesthesia. Further, large-scale studies in AS patients during EVT and in patients undergoing different surgeries and anesthesia are required to validate the LIR.
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Affiliation(s)
| | | | | | | | | | - Dennis E Feierman
- Department of Anesthesiology
- IRB, Maimonides Medical Center, Brooklyn NY
| | | | - Goded Shahaf
- Applied Neurophysiology Lab, Rambam Health Care Campus, Haifa
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2
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Vlisides PE, Li D, Maywood M, Zierau M, Lapointe AP, Brooks J, McKinney AM, Leis AM, Mentz G, Mashour GA. Electroencephalographic Biomarkers, Cerebral Oximetry, and Postoperative Cognitive Function in Adult Noncardiac Surgical Patients: A Prospective Cohort Study. Anesthesiology 2023; 139:568-579. [PMID: 37364282 PMCID: PMC10592490 DOI: 10.1097/aln.0000000000004664] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
BACKGROUND Perioperative neurocognitive disorders are a major public health issue, although there are no validated neurophysiologic biomarkers that predict cognitive function after surgery. This study tested the hypothesis that preoperative posterior electroencephalographic alpha power, alpha frontal-parietal connectivity, and cerebral oximetry would each correlate with postoperative neurocognitive function. METHODS This was a single-center, prospective, observational study of adult (older than 18 yr) male and female noncardiac surgery patients. Whole-scalp, 16-channel electroencephalography and cerebral oximetry were recorded in the preoperative, intraoperative, and immediate postoperative settings. The primary outcome was the mean postoperative T-score of three National Institutes of Health Toolbox Cognition tests-Flanker Inhibitory Control and Attention, List Sorting Working Memory, and Pattern Comparison Processing Speed. These tests were obtained at preoperative baseline and on the first two postoperative mornings. The lowest average score from the first two postoperative days was used for the primary analysis. Delirium was a secondary outcome (via 3-min Confusion Assessment Method) measured in the postanesthesia care unit and twice daily for the first 3 postoperative days. Last, patient-reported outcomes related to cognition and overall well-being were collected 3 months postdischarge. RESULTS Sixty-four participants were recruited with a median (interquartile range) age of 59 (48 to 66) yr. After adjustment for baseline cognitive function scores, no significant partial correlation (ρ) was detected between postoperative cognition scores and preoperative relative posterior alpha power (%; ρ = -0.03, P = 0.854), alpha frontal-parietal connectivity (via weight phase lag index; ρ = -0.10, P = 0.570, respectively), or preoperative cerebral oximetry (%; ρ = 0.21, P = 0.246). Only intraoperative frontal-parietal theta connectivity was associated with postoperative delirium (F[1,6,291] = 4.53, P = 0.034). No electroencephalographic or oximetry biomarkers were associated with cognitive or functional outcomes 3 months postdischarge. CONCLUSIONS Preoperative posterior alpha power, frontal-parietal connectivity, and cerebral oximetry were not associated with cognitive function after noncardiac surgery. EDITOR’S PERSPECTIVE
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Affiliation(s)
- Phillip E. Vlisides
- Department of Anesthesiology, Michigan Medicine, Ann Arbor, MI USA
- Center for Consciousness Science, University of Michigan, Ann Arbor, MI USA
| | - Duan Li
- Department of Anesthesiology, Michigan Medicine, Ann Arbor, MI USA
| | - Michael Maywood
- Department of Ophthalmology, William Beaumont Hospital, Royal Oak, MI, USA
| | - Mackenzie Zierau
- College of Health Professions, University of Detroit Mercy, Detroit, MI USA
| | - Andrew P. Lapointe
- Department of Radiology, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada
| | - Joseph Brooks
- Department of Orthopaedic Surgery, Michigan Medicine, Ann Arbor, MI USA
| | - Amy M. McKinney
- Department of Anesthesiology, Michigan Medicine, Ann Arbor, MI USA
| | - Aleda M. Leis
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI USA
| | - Graciela Mentz
- Department of Anesthesiology, Michigan Medicine, Ann Arbor, MI USA
| | - George A. Mashour
- Department of Anesthesiology, Michigan Medicine, Ann Arbor, MI USA
- Center for Consciousness Science, University of Michigan, Ann Arbor, MI USA
- Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI USA
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Ji S, Shi Y, Fan X, Jiang T, Yang X, Tao T, Ye B. Global trends in perioperative stroke research from 2003 to 2022: a web of science-based bibliometric and visual analysis. Front Neurol 2023; 14:1185326. [PMID: 37325224 PMCID: PMC10264628 DOI: 10.3389/fneur.2023.1185326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 04/27/2023] [Indexed: 06/17/2023] Open
Abstract
Background Perioperative stroke is a potentially devastating complication in surgical patients, which has attracted global attention. This retrospective bibliometric and visual analysis evaluates the status and global trends in perioperative stroke research. Methods Papers published between 2003 and 2022 were retrieved from the Web of Science core collection. Extracted data were summarized and analyzed using Microsoft Excel and further bibliometric and co-occurrence analyses were conducted using VOSviewer and CiteSpace software. Results Publications on perioperative stroke have increased over the years. The USA topped the list of countries with the highest number of publications and citations, while Canada had the highest mean citation frequency. The Journal of Vascular Surgery and Annals of Thoracic Surgery had the highest number of publications and citation frequency for perioperative stroke. Regarding authors, Malas, Mahmoud B. contributed the most publications to the field, and Harvard University had the highest number of publications (409 papers). Based on an overlay visualization map, timeline view, and the strongest strength burst of keywords, "antiplatelet therapy," "antithrombotic therapy," "carotid revascularization," "bleeding complications," "postoperative cognitive dysfunction," "intraoperative hypotension," "thrombectomy," "cerebral revascularization," "valve surgery," "tranexamic acid," and "frozen elephant trunk" were trending topics in perioperative stroke research. Conclusion Publications regarding perioperative stroke have experienced rapid growth in the past 20 years and are likely to continuously increase. Research on perioperative antiplatelet and antithrombotic, cardiovascular surgery, postoperative cognitive dysfunction, thrombectomy, tranexamic acid, and frozen elephant trunk has attracted increasing attention, and these topics are emerging hotspots of present research and possible candidates for future research.
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Affiliation(s)
- Shunpan Ji
- Department of Anesthesiology, Air Force Medical Center, Beijing, China
- Graduate School of China Medical University, Shenyang, China
| | - Yue Shi
- Department of Anesthesiology, Air Force Medical Center, Beijing, China
- Graduate School of China Medical University, Shenyang, China
| | - Xiaojing Fan
- Department of Anesthesiology, Air Force Medical Center, Beijing, China
| | - Tian Jiang
- Department of Anesthesiology, Air Force Medical Center, Beijing, China
| | - Xiaoming Yang
- Department of Anesthesiology, Air Force Medical Center, Beijing, China
| | - Tianzhu Tao
- Department of Anesthesiology, Air Force Medical Center, Beijing, China
- Graduate School of China Medical University, Shenyang, China
| | - Bo Ye
- Department of Anesthesiology, Air Force Medical Center, Beijing, China
- Graduate School of China Medical University, Shenyang, China
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Correlation between brain tissue oxygen tension and regional cerebral oximetry in uninjured human brain under conditions of changing ventilation strategy. J Clin Monit Comput 2022; 36:1227-1232. [PMID: 35113286 PMCID: PMC8812359 DOI: 10.1007/s10877-022-00821-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 01/25/2022] [Indexed: 11/09/2022]
Abstract
Controversy surrounds regional cerebral oximetry (rSO2) because extracranial contamination and unmeasured changes in cerebral arterial:venous ratio confound readings. Correlation of rSO2 with brain tissue oxygen (PbrO2), a “gold standard” for cerebral oxygenation, could help resolve this controversy but PbrO2 measurement is highly invasive. This was a prospective cohort study. The primary aim was to evaluate correlation between PbrO2 and rSO2 and the secondary aim was to investigate the relationship between changing ventilation regimens and measurement of PbrO2 and rSO2. Patients scheduled for elective removal of cerebral metastases were anesthetized with propofol and remifentanil, targeted to a BIS range 40–60. rSO2 was measured using the INVOS 5100B monitor and PbrO2 using the Licox brain monitoring system. The Licox probe was placed into an area of normal brain within the tumor excision corridor. FiO2 and minute ventilation were sequentially adjusted to achieve two set points: (1) FiO2 0.3 and paCO2 30 mmHg, (2) FiO2 1.0 and paCO2 40 mmHg. PbrO2 and rSO2 were recorded at each. Nine participants were included in the final analysis, which showed a positive Spearman’s correlation (r = 0.50, p = 0.036) between PbrO2 and rSO2. From set point 1 to set point 2, PbrO2 increased from median 6.0, IQR 4.0–11.3 to median 22.5, IQR 9.8–43.6, p = 0.015; rSO2 increased from median 68.0, IQR 62.5–80.5 to median 83.0, IQR 74.0–90.0, p = 0.047. Correlation between PbrO2 and rSO2 is evident. Increasing FiO2 and PaCO2 results in significant increases in cerebral oxygenation measured by both monitors.
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Perioperative Care of Patients at High Risk for Stroke During or After Non-cardiac, Non-neurological Surgery: 2020 Guidelines From the Society for Neuroscience in Anesthesiology and Critical Care. J Neurosurg Anesthesiol 2021; 32:210-226. [PMID: 32433102 DOI: 10.1097/ana.0000000000000686] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Perioperative stroke is associated with considerable morbidity and mortality. Stroke recognition and diagnosis are challenging perioperatively, and surgical patients receive therapeutic interventions less frequently compared with stroke patients in the outpatient setting. These updated guidelines from the Society for Neuroscience in Anesthesiology and Critical Care provide evidence-based recommendations regarding perioperative care of patients at high risk for stroke. Recommended areas for future investigation are also proposed.
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Postoperative Screening With the Modified National Institutes of Health Stroke Scale After Noncardiac Surgery: A Pilot Study. J Neurosurg Anesthesiol 2021; 34:327-332. [PMID: 34054030 DOI: 10.1097/ana.0000000000000779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 04/20/2021] [Indexed: 11/26/2022]
Abstract
BACKGROUND Perioperative stroke is associated with high rates of morbidity and mortality, yet there is no validated screening tool. The modified National Institutes of Health Stroke Scale (mNIHSS) is validated for use in nonsurgical strokes but is not well-studied in surgical patients. We evaluated perioperative changes in the mNIHSS score in noncardiac, non-neurological surgery patients, feasibility in the perioperative setting, and the relationship between baseline cognitive screening and change in mNIHSS score. METHODS Patients aged 65 years and above presenting for noncardiac, non-neurological surgery were prospectively recruited. Those with significant preoperative cognitive impairment (Montreal Cognitive Assessment score [MoCA] ≤17) were excluded. mNIHSS was assessed preoperatively, on postoperative day (POD) 0, POD 1, and POD 2, demographic data collected, and feedback solicited from participants. Changes in mNIHSS from baseline, time to completion, and relationship between baseline MoCA score and change in mNIHSS score were analyzed. RESULTS Twenty-five patients were enrolled into the study; no overt strokes occurred. Median mNIHSS score increased between baseline (0 interquartile range [IQR 0 to 1]) and POD 0 (2 [IQR 0 to 3.5]; P<0.001) but not between baseline and POD 1 (0.5 [IQR 0 to 1.5]; P=0.174) or POD 2 (0 [IQR 0 to 1]; P=0.650). Time to complete the mNIHSS at baseline was 3.5 minutes (SD 0.8), increasing to 4.1 minutes (SD 1.0) on POD 0 (P=0.0249). Baseline MoCA score was correlated with mNIHSS score change (P=0.038). Perioperative administration of the mNIHSS was feasible, and acceptable to patients. CONCLUSIONS Changes in mNIHSS score can occur early after surgery in the absence of overt stroke. Assessment of mNIHSS appears feasible in the perioperative setting, although further research is required to define its role in detecting perioperative stroke.
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Abstract
Stroke is associated with substantial morbidity and mortality. The aim of this review is to provide an evidence-based synthesis of the literature related to perioperative stroke, including its etiology, common risk factors, and potential risk reduction strategies. In addition, the authors will discuss screening methods for the detection of postoperative cerebral ischemia and how multidisciplinary collaborations, including endovascular interventions, should be considered to improve patient outcomes. Lastly, the authors will discuss the clinical and scientific knowledge gaps that need to be addressed to reduce the incidence and improve outcomes after perioperative stroke.
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Møller A, Wetterslev J, Shahidi S, Hellemann D, Secher NH, Pedersen OB, Marcussen KV, Ramsing BGU, Mortensen A, Nielsen HB. Effect of low vs high haemoglobin transfusion trigger on cardiac output in patients undergoing elective vascular surgery: Post-hoc analysis of a randomized trial. Acta Anaesthesiol Scand 2021; 65:302-312. [PMID: 33141936 DOI: 10.1111/aas.13733] [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: 06/11/2020] [Revised: 10/06/2020] [Accepted: 10/07/2020] [Indexed: 12/01/2022]
Abstract
BACKGROUND During vascular surgery, restricted red-cell transfusion reduces frontal lobe oxygen (ScO2 ) saturation as determined by near-infrared spectroscopy. We evaluated whether inadequate increase in cardiac output (CO) following haemodilution explains reduction in ScO2 . METHODS This is a post-hoc analysis of data from the Transfusion in Vascular surgery (TV) Trial where patients were randomized on haemoglobin drop below 9.7 g/dL to red-cell transfusion at haemoglobin below 8.0 (low-trigger) vs 9.7 g/dL (high-trigger). Fluid administration was guided by optimizing stroke volume. We compared mean intraoperative levels of CO, haemoglobin, oxygen delivery, and CO at nadir ScO2 with linear regression adjusted for age, operation type and baseline. Data for 46 patients randomized before end of surgery were included for analysis. RESULTS The low-trigger resulted in a 7.1% lower mean intraoperative haemoglobin level (mean difference, -0.74 g/dL; P < .001) and reduced volume of red-cell transfused (median [inter-quartile range], 0 [0-300] vs 450 mL [300-675]; P < .001) compared with the high-trigger group. Mean CO during surgery was numerically 7.3% higher in the low-trigger compared with the high-trigger group (mean difference, 0.36 L/min; 95% confidence interval (CI.95), -0.05 to 0.78; P = .092; n = 42). At the nadir ScO2 -level, CO was 11.9% higher in the low-trigger group (mean difference, 0.58 L/min; CI.95, 0.10-1.07; P = .024). No difference in oxygen delivery was detected between trial groups (MD, 1.39 dLO2 /min; CI.95, -6.16 to 8.93; P = .721). CONCLUSION Vascular surgical patients exposed to restrictive RBC transfusion elicit the expected increase in CO making it unlikely that their potentially limited cardiac capacity explains the associated ScO2 decrease.
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Affiliation(s)
- Anders Møller
- Department of Anaesthesia and Intensive care Næstved‐Slagelse‐Ringsted Slagelse Hospital Slagelse Denmark
| | - Jørn Wetterslev
- Copenhagen Trial Unit Centre for Clinical Intervention Research, Rigshospitalet Copenhagen Denmark
| | - Saeid Shahidi
- Department of Cardiology and Vascular Surgery Zealand University Hospital Roskilde Roskilde Denmark
| | - Dorthe Hellemann
- Department of Anaesthesia and Intensive care Næstved‐Slagelse‐Ringsted Slagelse Hospital Slagelse Denmark
| | - Niels H. Secher
- Department of Anaesthesia, Rigshospitalet University of Copenhagen Copenhagen Denmark
| | - Ole B. Pedersen
- Department of Clinical Immunology Næstved Hospital Nastved Denmark
| | - Klaus V. Marcussen
- Department of Anaesthesia and Intensive care Næstved‐Slagelse‐Ringsted Slagelse Hospital Slagelse Denmark
| | - Benedicte G. U. Ramsing
- Department of Anaesthesia and Intensive care Næstved‐Slagelse‐Ringsted Slagelse Hospital Slagelse Denmark
| | - Anette Mortensen
- Department of Anaesthesia and Intensive care Næstved‐Slagelse‐Ringsted Slagelse Hospital Slagelse Denmark
| | - Henning B. Nielsen
- Department of Anaesthesia Zealand University Hospital Roskilde Roskilde Denmark
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Businger J, Fort AC, Vlisides PE, Cobas M, Akca O. Management of Acute Ischemic Stroke-Specific Focus on Anesthetic Management for Mechanical Thrombectomy. Anesth Analg 2020; 131:1124-1134. [PMID: 32925333 DOI: 10.1213/ane.0000000000004959] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Acute ischemic stroke is a neurological emergency with a high likelihood of morbidity, mortality, and long-term disability. Modern stroke care involves multidisciplinary management by neurologists, radiologists, neurosurgeons, and anesthesiologists. Current American Heart Association/American Stroke Association (AHA/ASA) guidelines recommend thrombolytic therapy with intravenous (IV) alteplase within the first 3-4.5 hours of initial stroke symptoms and endovascular mechanical thrombectomy within the first 16-24 hours depending on specific inclusion criteria. The anesthesia and critical care provider may become involved for airway management due to worsening neurologic status or to enable computerized tomography (CT) or magnetic resonance imaging (MRI) scanning, to facilitate mechanical thrombectomy, or to manage critical care of stroke patients. Existing data are unclear whether the mechanical thrombectomy procedure is best performed under general anesthesia or sedation. Retrospective cohort trials favor sedation over general anesthesia, but recent randomized controlled trials (RCT) neither suggest superiority nor inferiority of sedation over general anesthesia. Regardless of anesthesia type, a critical element of intraprocedural stroke care is tight blood pressure management. At different phases of stroke care, different blood pressure targets are recommended. This narrative review will focus on the anesthesia and critical care providers' roles in the management of both perioperative stroke and acute ischemic stroke with a focus on anesthetic management for mechanical thrombectomy.
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Affiliation(s)
- Jerrad Businger
- From the Division of Critical Care, Department of Anesthesiology & Perioperative Medicine, Neuroscience Intensive Care Unit (ICU), Comprehensive Stroke Center, University of Louisville, Louisville, Kentuckys
| | - Alexander C Fort
- Department of Anesthesiology, University of Miami, Miami, Florida
| | - Phillip E Vlisides
- Department of Anesthesiology, University of Michigan, Ann Arbor, Michigan
| | - Miguel Cobas
- Department of Anesthesiology, University of Miami, Miami, Florida
| | - Ozan Akca
- Department of Anesthesiology and Perioperative Medicine, Stroke ICU, University of Louisville, Louisville, Kentucky
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Abstract
Perioperative stroke is defined as an ischemic cerebrovascular event that occurs during or within 30 days after surgery and is associated with an increased perioperative risk of morbidity and mortality. Depending on the type of surgery stroke is diagnosed in up to 11% of all patients in the perioperative period. Patients with a history of ischemic stroke or transitory ischemic attack have an increased risk for perioperative stroke. Therefore, a critical assessment of indications and the timing of surgery are crucial to prevent recurring stroke in this patient population. Importantly, individualized blood pressure management is essential for optimization of cerebral perfusion during the perioperative period.This article provides a summary of the epidemiology, risk factors, and etiology of perioperative stroke. Moreover, possible preventive strategies relevant for the anesthesiologist are reviewed.
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Affiliation(s)
- M Fischer
- Klinik und Poliklinik für Anästhesiologie, Universitätsklinikum Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Deutschland.
| | - U Kahl
- Klinik und Poliklinik für Anästhesiologie, Universitätsklinikum Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Deutschland
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Vlisides PE, Avidan MS, Mashour GA. Uncovering covert stroke in surgical patients. Lancet 2019; 394:982-984. [PMID: 31422896 DOI: 10.1016/s0140-6736(19)31770-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 07/08/2019] [Indexed: 11/17/2022]
Affiliation(s)
- Phillip E Vlisides
- Department of Anesthesiology and Center for Consciousness Science, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Michael S Avidan
- Department of Anesthesiology, Washington University School of Medicine, St Louis, MO, USA
| | - George A Mashour
- Department of Anesthesiology and Center for Consciousness Science, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
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