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Raghavan V, Sobczyk O, Sayin ES, Poublanc J, Skanda A, Duffin J, Venkatraghavan L, Fisher JA, Mikulis DJ. Assessment of Cerebrovascular Reactivity Using CO 2-BOLD MRI: A 15-Year, Single Center Experience. J Magn Reson Imaging 2024; 60:954-961. [PMID: 38135486 DOI: 10.1002/jmri.29176] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 11/21/2023] [Accepted: 11/22/2023] [Indexed: 12/24/2023] Open
Abstract
BACKGROUND Cerebrovascular reactivity (CVR) is a measure of the change in cerebral blood flow (CBF) in response to a vasoactive challenge. It is a useful indicator of the brain's vascular health. PURPOSE To evaluate the factors that influence successful and unsuccessful CVR examinations using precise arterial and end-tidal partial pressure of CO2 control during blood oxygen level-dependent (BOLD) MRI. STUDY TYPE Retrospective. SUBJECTS Patients that underwent a CVR between October 2005 and May 2021 were studied (total of 1162 CVR examinations). The mean (±SD) age was 46.1 (±18.8) years, and 352 patients (43%) were female. FIELD STRENGTH/SEQUENCE 3 T; T1-weighted images, T2*-weighed two-dimensional gradient-echo sequence with standard echo-planar readout. ASSESSMENT Measurements were obtained following precise hypercapnic stimuli using BOLD MRI as a surrogate of CBF. Successful CVR examinations were defined as those where: 1) patients were able to complete CVR testing, and 2) a clinically useful CVR map was generated. Unsuccessful examinations were defined as those where patients were not able to complete the CVR examination or the CVR maps were judged to be unreliable due to, for example, excessive head motion, and poor PETCO2 targeting. STATISTICAL ANALYSIS Successful and unsuccessful CVR examinations between hypercapnic stimuli, and between different patterns of stimulus were compared with Chi-Square tests. Interobserver variability was determined by using the intraclass correlation coefficient (P < 0.05 is significant). RESULTS In total 1115 CVR tests in 662 patients were included in the final analysis. The success rate of generating CVR maps was 90.8% (1012 of 1115). Among the different hypercapnic stimuli, those containing a step plus a ramp protocol was the most successful (95.18%). Among the unsuccessful examinations (9.23%), most were patient related (89.3%), the most common of which was difficulty breathing. DATA CONCLUSION CO2-BOLD MRI CVR studies are well tolerated with a high success rate. EVIDENCE LEVEL 4 TECHNICAL EFFICACY: Stage 3.
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Affiliation(s)
- Vishvak Raghavan
- School of Computer Science, McGill University, Montreal, Quebec, Canada
| | - Olivia Sobczyk
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory, University Health Network, Toronto, Ontario, Canada
| | - Ece Su Sayin
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory, University Health Network, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Julien Poublanc
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory, University Health Network, Toronto, Ontario, Canada
| | - Abby Skanda
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory, University Health Network, Toronto, Ontario, Canada
| | - James Duffin
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Lashmi Venkatraghavan
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Joseph A Fisher
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory, University Health Network, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada
| | - David J Mikulis
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory, University Health Network, Toronto, Ontario, Canada
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2
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Gavriely N, Rasanen JO, Saar SA, Lamhaut L, Hutin A, Lidouren F, Abi Zeid Daou Y, Tissier R. Novel gas mixture combined with an auto-transfusion tourniquet enhances cerebral O 2 transport and hemodynamic indices in CPR swine. Part B - A pilot experimental study. Resusc Plus 2024; 19:100681. [PMID: 38966232 PMCID: PMC11223111 DOI: 10.1016/j.resplu.2024.100681] [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: 02/16/2024] [Revised: 05/21/2024] [Accepted: 05/24/2024] [Indexed: 07/06/2024] Open
Abstract
Objectives The cognitive outcome of CPR is poor. This study aims to evaluate if enhancing blood flow to the brain and oxygen dissociation from the hemoglobin improve cerebral O2 transport during CPR in cardiac arrest swine. Methods Standard swine-CPR model of induced VF and recovery was treated with an auto-transfusion tourniquet (A-TT®; HemaShock® (HS) Oneg HaKarmel Ltd. Israel) and ventilation with a novel mixture of 30% Oxygen, 5% CO2, and 65% Argon (COXAR™). Five swine received the study treatment and 5 controls standard therapy. Animals were anesthetized, ventilated, and instrumented for blood draws and pressure measurements. Five minutes of no-CPR arrest were followed by 10 min of mechanical CPR with and without COXAR-HS™ enhancement followed by defibrillation and 45 min post ROSC follow-up. Results All 5 COXAR-HS™ animals were resuscitated successfully as opposed to 3 of the control animals. Systolic (p < 0.05), and diastolic (p < 0.01) blood pressures, and coronary (p < 0.001) and cerebral (p < 0.05) perfusion pressures were higher in the COXAR-HS™ group after ROSC, as well as cerebral flow and O2 provided to the brain (p < 0.05). Blood pressure maintenance after ROSC required much higher doses of norepinephrine in the 3 resuscitated control animals vs. the 5 COXAR-HS™ animals (p < 0.05). jugular vein PO2 and SO2 exceeded 50 mmHg and 50%, respectively with COXAR-HS™. Conclusions In this pilot experimental study, COXAR-HS™ was associated with higher diastolic blood pressure and coronary perfusion pressure with lower need of vasopressors after ROSC without significant differences prior to ROSC. The higher PjvO2 and SjvO2 suggest enhanced O2 provision to the brain mitochondria, while limb compression by the HS counteracts the vasodilatory effect of the CO2. Further studies are needed to explore and validate the COXAR-HS™ effects on actual post-ROSC brain functionality.
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Affiliation(s)
- Noam Gavriely
- Technion, Israel Institute of Technology (ret), Haifa, Israel
- Oneg HaKarmel Ltd., Tirat Carmel, Israel
| | | | | | - Lionel Lamhaut
- Université de Paris – Cité, Paris, France
- Necker University Hospital, Assistance Publique-Hôpitaux de Paris, SAMU de Paris-ICU, 75015 Paris, France
- Paris Sudden Death Expertise Center, INSERM U970, Paris France
| | - Alice Hutin
- Necker University Hospital, Assistance Publique-Hôpitaux de Paris, SAMU de Paris-ICU, 75015 Paris, France
- Ecole Nationale Vétérinaire d’Alfort, IMRB, 94700 Maisons-Alfort, France
| | - Fanny Lidouren
- Université Paris Est Créteil, INSERM, IMRB, 94010 Créteil, France
- Ecole Nationale Vétérinaire d’Alfort, IMRB, 94700 Maisons-Alfort, France
| | - Yara Abi Zeid Daou
- Université Paris Est Créteil, INSERM, IMRB, 94010 Créteil, France
- Ecole Nationale Vétérinaire d’Alfort, IMRB, 94700 Maisons-Alfort, France
| | - Renaud Tissier
- Université Paris Est Créteil, INSERM, IMRB, 94010 Créteil, France
- Ecole Nationale Vétérinaire d’Alfort, IMRB, 94700 Maisons-Alfort, France
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Kapoor A, Dutt S, Alitin JPM, Sible IJ, Marshall A, Shenasa F, Engstrom AC, Gaubert A, Shao X, Bradford DR, Rodgers K, Mather M, Wang DJJ, Nation DA. Older adults with reduced cerebrovascular reactivity exhibit high white matter hyperintensity burden. Neurobiol Aging 2024; 139:5-10. [PMID: 38579393 DOI: 10.1016/j.neurobiolaging.2024.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 03/17/2024] [Accepted: 03/22/2024] [Indexed: 04/07/2024]
Abstract
Cerebrovascular reactivity (CVR) deficits may contribute to small vessel disease, such as white matter hyperintensities (WMH). Moreover, apolipoprotein-e4 (APOE4) carriers at genetic risk for Alzheimer's disease exhibit cerebrovascular dysfunction relative to non-carriers. We examined whether older adults, and APOE4 carriers specifically, with diminished CVR would exhibit higher WMH burden. Independently living older adults (N = 125, mean age = 69.2 years; SD = 7.6; 31.2% male) free of dementia or clinical stroke underwent brain MRI to quantify cerebral perfusion during CVR to hypercapnia and hypocapnia and determine WMH volume. Adjusting for age, sex and intracranial volume, hierarchical regression analysis revealed a significant association between whole brain CVR to hypercapnia and WMH overall [B = -.02, 95% CI (-.04, -.008), p =.003] and in APOE4 carriers [B = -.03, 95% CI (-.06, -.009), p =.009]. Findings suggest deficits in cerebral vasodilatory capacity are associated with WMH burden in older adults and future studies are warranted to further delineate the effect of APOE4 on precipitating WMH.
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Affiliation(s)
- Arunima Kapoor
- Department of Psychological Science, University of California, Irvine, Irvine, CA, USA
| | - Shubir Dutt
- Department of Psychology, University of Southern California, Los Angeles, CA, USA
| | - John Paul M Alitin
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA, USA
| | - Isabel J Sible
- Department of Psychology, University of Southern California, Los Angeles, CA, USA
| | - Anisa Marshall
- Department of Psychology, University of Southern California, Los Angeles, CA, USA
| | - Fatemah Shenasa
- Department of Psychological Science, University of California, Irvine, Irvine, CA, USA
| | - Allison C Engstrom
- Department of Psychological Science, University of California, Irvine, Irvine, CA, USA
| | - Aimée Gaubert
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA, USA
| | - Xingfeng Shao
- Stevens Neuroimaging and Informatics Institute, University of Southern California, Los Angeles, CA, USA
| | - David Robert Bradford
- Center for Innovations in Brain Science, Department of Pharmacology, University of Arizona, Tucson, AZ, USA
| | - Kathleen Rodgers
- Center for Innovations in Brain Science, Department of Pharmacology, University of Arizona, Tucson, AZ, USA
| | - Mara Mather
- University of Southern California Leonard Davis School of Gerontology, USA
| | - Danny J J Wang
- Stevens Neuroimaging and Informatics Institute, University of Southern California, Los Angeles, CA, USA
| | - Daniel A Nation
- University of Southern California Leonard Davis School of Gerontology, USA; Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, University of Southern California Keck School of Medicine, USA.
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Brown LK. Targeting Hypercapnia in Chronic Lung Disease and Obesity Hypoventilation: Benefits and Challenges. Sleep Med Clin 2024; 19:357-369. [PMID: 38692758 DOI: 10.1016/j.jsmc.2024.02.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
Hypoventilation is a complication that is not uncommon in chronic obstructive pulmonary disease and calls for both medical treatment of the underlying disease and, frequently, noninvasive ventilation either during exacerbations requiring hospitalization or in a chronic state in the patient at home. Obesity hypoventilation syndrome by definition is associated with ventilatory failure and hypercapnia. It may or may not be accompanied by obstructive sleep apnea, which when detected becomes an additional target for positive airway pressure treatment. Intensive research has not completely resolved the best choice of treatment, and the simplest modality, continuous positive airway pressure, may still be entertained.
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Affiliation(s)
- Lee K Brown
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, University of New Mexico School of Medicine, Albuquerque, NM, USA.
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5
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Beekman R, Gilmore EJ. Cerebral edema following cardiac arrest: Are all shades of gray equal? Resuscitation 2024; 198:110213. [PMID: 38636600 DOI: 10.1016/j.resuscitation.2024.110213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 04/05/2024] [Indexed: 04/20/2024]
Affiliation(s)
- Rachel Beekman
- Department of Neurology, Yale School of Medicine, New Haven, CT, United States.
| | - Emily J Gilmore
- Department of Neurology, Yale School of Medicine, New Haven, CT, United States
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6
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Ahmed A, Patel B, Wang R, Luna L, Verde A, Besheli LD, Intrapiromkul J, Nabi M, Edpuganti N, Deng F, Yedavalli V. Clinical applications of arterial spin labeling of the intracranial compartment in vascular anomalies-A case-based review. Neuroradiol J 2023; 36:638-650. [PMID: 36172883 PMCID: PMC10649537 DOI: 10.1177/19714009221130490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Arterial spin labeling (ASL) is a magnetic resonance perfusion technique that allows for quantification of cerebral blood flow (CBF) without the use of contrast or radiation. Several applications of ASL have been described in diagnosis of strokes and stroke mimics, intracranial tumors, and other conditions. Various vascular anomalies exhibit specific CBF patterns that correlate with different signal intensities on ASL. In this case-based review, we demonstrate the utility of ASL in diagnosis and surveillance of vascular anomalies in the intracranial compartment.
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Affiliation(s)
- Amara Ahmed
- Florida State University College of Medicine, Tallahassee, FL, USA
| | - Bhumi Patel
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Richard Wang
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Licia Luna
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD, USA
| | | | - Laleh Daftari Besheli
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Jarunee Intrapiromkul
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Mehreen Nabi
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Namratha Edpuganti
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Francis Deng
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Vivek Yedavalli
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD, USA
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7
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A novel computational model for cerebral blood flow rate control mechanisms to evaluate physiological cases. Biomed Signal Process Control 2022. [DOI: 10.1016/j.bspc.2022.103851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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8
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Daftari Besheli L, Ahmed A, Hamam O, Luna L, Sun LR, Urrutia V, Hillis AE, Tekes-Brady A, Yedavalli V. Arterial Spin Labeling technique and clinical applications of the intracranial compartment in stroke and stroke mimics - A case-based review. Neuroradiol J 2022; 35:437-453. [PMID: 35635512 PMCID: PMC9437493 DOI: 10.1177/19714009221098806] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2023] Open
Abstract
Magnetic resonance imaging perfusion (MRP) techniques can improve the selection of acute ischemic stroke patients for treatment by estimating the salvageable area of decreased perfusion, that is, penumbra. Arterial spin labeling (ASL) is a noncontrast MRP technique that is used to assess cerebral blood flow without the use of intravenous gadolinium contrast. Thus, ASL is of particular interest in stroke imaging. This article will review clinical applications of ASL in stroke such as assessment of the core infarct and penumbra, localization of the vascular occlusion, and collateral status. Given the nonspecific symptoms that patients can present with, differentiating between stroke and a stroke mimic is a diagnostic dilemma. ASL not only helps in differentiating stroke from stroke mimic but also can be used to specify the exact mimic when used in conjunction with the symptomatology and structural imaging. In addition to a case-based overview of clinical applications of the ASL in stroke and stroke mimics in this article, the more commonly used ASL labeling techniques as well as emerging ASL techniques, future developments, and limitations will be reviewed.
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Affiliation(s)
| | - Amara Ahmed
- Florida State University College of
Medicine, Tallahassee, FL, USA
| | - Omar Hamam
- Johns Hopkins School of
Medicine, Baltimore, MD, USA
| | - Licia Luna
- Johns Hopkins School of
Medicine, Baltimore, MD, USA
| | - Lisa R Sun
- Johns Hopkins School of
Medicine, Baltimore, MD, USA
| | | | - Argye E Hillis
- Johns Hopkins University School of
Medicine, Baltimore, MD, USA
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9
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A perspective on spaceflight associated neuro-ocular syndrome causation secondary to elevated venous sinus pressure. NPJ Microgravity 2022; 8:3. [PMID: 35169156 PMCID: PMC8847421 DOI: 10.1038/s41526-022-00188-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 01/21/2022] [Indexed: 11/17/2022] Open
Abstract
Spaceflight associated neuro-ocular syndrome (SANS) alters the vision of astronauts during long-duration spaceflights. There is controversy regarding SANS being similar to patients with idiopathic intracranial hypertension (IIH). IIH has been shown to be due to an elevation in venous sinus pressure. The literature suggests an increase in jugular vein pressure secondary to a headward shift of fluid occurs in SANS but this may not be enough to significantly alter the intracranial pressure (ICP). The literature regarding cardiac output and cerebral blood flow (CBF) in long-duration spaceflight is contradictory, however, more recent data suggests increased flow. Recent modelling has shown that an increase in CBF can significantly increase sinus pressure. The purpose of the present paper is to review the SANS vascular dynamics literature and through mathematical modelling suggest the possible underlying cause of SANS as an elevation in venous sinus pressure, secondary to the redistribution of fluids towards the head, together with a significant increase in pressure drop across the venous system related to the CBF.
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10
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The impact of prehospital endotracheal intubation on mortality in traumatic brain injury. Am J Emerg Med 2022; 55:152-156. [DOI: 10.1016/j.ajem.2022.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 01/22/2022] [Accepted: 02/02/2022] [Indexed: 11/20/2022] Open
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Tamayo A, Siepmann T. Regulation of Blood Flow in the Cerebral Posterior Circulation by Parasympathetic Nerve Fibers: Physiological Background and Possible Clinical Implications in Patients With Vertebrobasilar Stroke. Front Neurol 2021; 12:660373. [PMID: 34777191 PMCID: PMC8585859 DOI: 10.3389/fneur.2021.660373] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 09/23/2021] [Indexed: 01/14/2023] Open
Abstract
Posterior circulation involves the vertebrobasilar arteries, which supply oxygen and glucose to vital human brainstem structures and other areas. This complex circulatory- perfusion system is not homogenous throughout the day; rather, its hemodynamic changes rely on physiological demands, ensuring brainstem perfusion. This dynamic autoregulatory pattern maintains cerebral perfusion during blood pressure changes. Accumulative evidence suggests that activity within the autonomic nervous system is involved in the regulation of cerebral blood flow. Neither the sympathetic nor parasympathetic nervous systems work independently. Functional studies have shown a tight and complicated cross talk between these systems. In pathological processes where sympathetic stimulation is present, systemic vasoconstriction is followed, representing the most important CNS parasympathetic trigger that will promote local vasodilation. Stroke is a clear example of this process. The posterior circulation is affected in 30% of strokes, causing high morbidity and mortality outcomes. Currently, the management of ischemic stroke is focused on thrombolytic treatment and endovascular thrombectomy within an overall tight 4.5 to 6 h ischemic time window. Therefore, the autonomic nervous system could represent a potential therapeutic target to modulate reperfusion after cerebral ischemia through vasodilation, which could potentially decrease infarct size and increase the thrombolytic therapeutic ischemic window. In addition, shifting the autonomic nervous system balance toward its parasympathetic branch has shown to enhance neurogenesis and decrease local inflammation. Regretfully, the vast majority of animal models and human research on neuromodulation during brain ischemia have been focused on anterior circulation with disappointing results. In addition, the source of parasympathetic inputs in the vertebrobasilar system in humans is poorly understood, substantiating a gap and controversy in this area. Here, we reviewed current available literature regarding the parasympathetic vascular function and challenges of its stimulation in the vertebrobasilar system.
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Affiliation(s)
- Arturo Tamayo
- The Max Rady Faculty of Health Sciences, Department of Medicine, Section of Neurology, WRHA, Winnipeg and Brandon Regional Health Centre, University of Manitoba, Winnipeg, MB, Canada
- Department of Health Care Sciences, Center for Clinical Research and Management Education, Dresden International University, Dresden, Germany
| | - Timo Siepmann
- Department of Health Care Sciences, Center for Clinical Research and Management Education, Dresden International University, Dresden, Germany
- Department of Neurology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
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12
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Cao R, Tran A, Li J, Xu Z, Sun N, Zuo Z, Hu S. Hemodynamic and oxygen-metabolic responses of the awake mouse brain to hypercapnia revealed by multi-parametric photoacoustic microscopy. J Cereb Blood Flow Metab 2021; 41:2628-2639. [PMID: 33899557 PMCID: PMC8504963 DOI: 10.1177/0271678x211010352] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 03/13/2021] [Accepted: 03/18/2021] [Indexed: 11/16/2022]
Abstract
A widely used cerebrovascular stimulus and common pathophysiologic condition, hypercapnia is of great interest in brain research. However, it remains controversial how hypercapnia affects brain hemodynamics and energy metabolism. By using multi-parametric photoacoustic microscopy, the multifaceted responses of the awake mouse brain to different levels of hypercapnia are investigated. Our results show significant and vessel type-dependent increases of the vessel diameter and blood flow in response to the hypercapnic challenges, along with a decrease in oxygen extraction fraction due to elevated venous blood oxygenation. Interestingly, the increased blood flow and decreased oxygen extraction are not commensurate with each other, which leads to reduced cerebral oxygen metabolism. Further, time-lapse imaging over 2-hour chronic hypercapnic challenges reveals that the structural, functional, and metabolic changes induced by severe hypercapnia (10% CO2) are not only more pronounced but more enduring than those induced by mild hypercapnia (5% CO2), indicating that the extent of brain's compensatory response to chronic hypercapnia is inversely related to the severity of the challenge. Offering quantitative, dynamic, and CO2 level-dependent insights into the hemodynamic and metabolic responses of the brain to hypercapnia, these findings might provide useful guidance to the application of hypercapnia in brain research.
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Affiliation(s)
- Rui Cao
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Angela Tran
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Jun Li
- Department of Anesthesiology, University of Virginia, Charlottesville, VA, USA
| | - Zhiqiang Xu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Naidi Sun
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Zhiyi Zuo
- Department of Anesthesiology, University of Virginia, Charlottesville, VA, USA
| | - Song Hu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA
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13
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One-pot synthesis of carboxymethyl-dextran coated iron oxide nanoparticles (CION) for preclinical fMRI and MRA applications. Neuroimage 2021; 238:118213. [PMID: 34116153 PMCID: PMC8418149 DOI: 10.1016/j.neuroimage.2021.118213] [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] [Received: 03/01/2021] [Revised: 05/15/2021] [Accepted: 05/25/2021] [Indexed: 11/21/2022] Open
Abstract
Superparamagnetic iron-oxide nanoparticles are robust contrast agents for magnetic resonance imaging (MRI) used for sensitive structural and functional mapping of the cerebral blood volume (CBV) when administered intravenously. To date, many CBV-MRI studies are conducted with Feraheme, manufactured for the clinical treatment of iron-deficiency. Unfortunately, Feraheme is currently not available outside the United States due to commercial and regulatory constraints, making CBV-MRI methods either inaccessible or very costly to achieve. To address this barrier, we developed a simple, one-pot recipe to synthesize Carboxymethyl-dextran coated Iron Oxide Nanoparticles, namely, “CION”, suitable for preclinical CBV-MRI applications. Here we disseminate a step-by-step instruction of our one-pot synthesis protocol, which allows CION to be produced in laboratories with minimal cost. We also characterized different CION-conjugations by manipulating polymer to metal stoichiometric ratio in terms of their size, surface chemistry, and chemical composition, and shifts in MR relaxivity and pharmacokinetics. We performed several proof-of-concept experiments in vivo, demonstrating the utility of CION for functional and structural MRI applications, including hypercapnic CO2 challenge, visual stimulation, targeted optogenetic stimulation, and microangiography. We also present evidence that CION can serve as a cross-modality research platform by showing concurrent in vivo optical and MRI measurement of CBV using fluorescent-labeled CION. The simplicity and cost-effectiveness of our one-pot synthesis method should allow researchers to reproduce CION and tailor the relaxivity and pharmacokinetics according to their imaging needs. It is our hope that this work makes CBV-MRI more openly available and affordable for a variety of research applications.
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14
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Roberts DR, Collins HR, Lee JK, Taylor JA, Turner M, Zaharchuk G, Wintermark M, Antonucci MU, Mulder ER, Gerlach DA, Asemani D, McGregor HR, Seidler RD. Altered cerebral perfusion in response to chronic mild hypercapnia and head-down tilt Bed rest as an analog for Spaceflight. Neuroradiology 2021; 63:1271-1281. [PMID: 33587162 DOI: 10.1007/s00234-021-02660-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 01/26/2021] [Indexed: 01/01/2023]
Abstract
PURPOSE Following prolonged stays on the International Space Station (ISS), some astronauts exhibit visual acuity changes, ophthalmological findings, and mildly elevated intracranial pressures as part of a novel process called spaceflight-associated neuro-ocular syndrome (SANS). To determine the pathophysiology of SANS, NASA conducted a multi-investigator study in which 11 healthy participants underwent head-down tilt bed rest, mimicking microgravity-induced cephalad fluid shifts, combined with elevated ambient CO2 levels similar to those on the ISS (HDT+CO2). As part of that study, we examined the effects of HDT+CO2 on cerebral perfusion. METHODS Using arterial spin labeling, we compared cerebral perfusion before, during, and after HDT+CO2 in participants who developed SANS (n = 5) with those who did not (n = 6). RESULTS All participants demonstrated a decrease in perfusion during HDT+CO2 (mean decrease of 25.1% at HDT7 and 16.2% at HDT29); however, the timing and degree of change varied between the groups. At day 7 of HDT+CO2, the SANS group experienced a greater reduction in perfusion than the non-SANS group (p =.05, 95% CI:-0.19 to 16.11, d=.94, large effect). Conversely, by day 29 of HDT+CO2, the SANS group had significantly higher perfusion (approaching their baseline) than the non-SANS group (p = .04, 95% CI:0.33 to 13.07, d=1.01, large effect). CONCLUSION Compared with baseline and recovery, HDT+CO2 resulted in reduced cerebral perfusion which varied based on SANS status. Further studies are needed to unravel the relative role of HDT vs hypercapnia, to determine if these perfusion changes are clinically relevant, and whether perfusion changes contribute to the development of SANS during spaceflight.
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Affiliation(s)
- Donna R Roberts
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA. .,Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA.
| | - Heather R Collins
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Jessica K Lee
- German Aerospace Center (DLR, Institute of Aerospace Medicine), Cologne, Germany.,Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, FL, USA
| | - James A Taylor
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Matthew Turner
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Greg Zaharchuk
- Department of Radiology, Division of Neuroradiology, Stanford University, Stanford, CA, USA
| | - Max Wintermark
- Department of Radiology, Division of Neuroradiology, Stanford University, Stanford, CA, USA
| | - Michael U Antonucci
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Edwin R Mulder
- German Aerospace Center (DLR, Institute of Aerospace Medicine), Cologne, Germany
| | - Darius A Gerlach
- German Aerospace Center (DLR, Institute of Aerospace Medicine), Cologne, Germany
| | - Davud Asemani
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Heather R McGregor
- Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, FL, USA
| | - Rachael D Seidler
- Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, FL, USA.,Norman Fixel Institute for Neurological Diseases, College of Health and Human Performance, University of Florida, Gainesville, FL, USA
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15
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Bambach S, Smith M, Morris PP, Campeau NG, Ho ML. Arterial Spin Labeling Applications in Pediatric and Adult Neurologic Disorders. J Magn Reson Imaging 2020; 55:698-719. [PMID: 33314349 DOI: 10.1002/jmri.27438] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 10/26/2020] [Accepted: 10/27/2020] [Indexed: 12/17/2022] Open
Abstract
Arterial spin labeling (ASL) is a powerful noncontrast magnetic resonance imaging (MRI) technique that enables quantitative evaluation of brain perfusion. To optimize the clinical and research utilization of ASL, radiologists and physicists must understand the technical considerations and age-related variations in normal and disease states. We discuss advanced applications of ASL across the lifespan, with example cases from children and adults covering a wide variety of pathologies. Through literature review and illustrated clinical cases, we highlight the subtleties as well as pitfalls of ASL interpretation. First, we review basic physical principles, techniques, and artifacts. This is followed by a discussion of normal perfusion variants based on age and physiology. The three major categories of perfusion abnormalities-hypoperfusion, hyperperfusion, and mixed patterns-are covered with an emphasis on clinical interpretation and relationship to the disease process. Major etiologies of hypoperfusion include large artery, small artery, and venous disease; other vascular conditions; global hypoxic-ischemic injury; and neurodegeneration. Hyperperfusion is characteristic of vascular malformations and tumors. Mixed perfusion patterns can be seen with epilepsy, migraine, trauma, infection/inflammation, and toxic-metabolic encephalopathy. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 3.
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Affiliation(s)
- Sven Bambach
- Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Mark Smith
- Department of Radiology, Nationwide Children's Hospital, Columbus, Ohio, USA
| | - P Pearse Morris
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Mai-Lan Ho
- Department of Radiology, Nationwide Children's Hospital, Columbus, Ohio, USA
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16
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Milej D, Abdalmalak A, Rajaram A, St. Lawrence K. Direct assessment of extracerebral signal contamination on optical measurements of cerebral blood flow, oxygenation, and metabolism. NEUROPHOTONICS 2020; 7:045002. [PMID: 33062801 PMCID: PMC7540337 DOI: 10.1117/1.nph.7.4.045002] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 09/04/2020] [Indexed: 05/08/2023]
Abstract
Significance: Near-infrared spectroscopy (NIRS) combined with diffuse correlation spectroscopy (DCS) provides a noninvasive approach for monitoring cerebral blood flow (CBF), oxygenation, and oxygen metabolism. However, these methods are vulnerable to signal contamination from the scalp. Our work evaluated methods of reducing the impact of this contamination using time-resolved (TR) NIRS and multidistance (MD) DCS. Aim: The magnitude of scalp contamination was evaluated by measuring the flow, oxygenation, and metabolic responses to a global hemodynamic challenge. Contamination was assessed by collecting data with and without impeding scalp blood flow. Approach: Experiments involved healthy participants. A pneumatic tourniquet was used to cause scalp ischemia, as confirmed by contrast-enhanced NIRS, and a computerized gas system to generate a hypercapnic challenge. Results: Comparing responses acquired with and without the tourniquet demonstrated that the TR-NIRS technique could reduce scalp contributions in hemodynamic signals up to 4 times (r SD = 3 cm ) and 6 times (r SD = 4 cm ). Similarly, blood flow responses from the scalp and brain could be separated by analyzing MD DCS data with a multilayer model. Using these techniques, there was no change in metabolism during hypercapnia, as expected, despite large increases in CBF and oxygenation. Conclusion: NIRS/DCS can accurately monitor CBF and metabolism with the appropriate enhancement to depth sensitivity, highlighting the potential of these techniques for neuromonitoring.
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Affiliation(s)
- Daniel Milej
- Lawson Health Research Institute, Imaging Program, London, Ontario, Canada
- Western University, Department of Medical Biophysics, London, Ontario, Canada
| | - Androu Abdalmalak
- Lawson Health Research Institute, Imaging Program, London, Ontario, Canada
- Western University, Department of Medical Biophysics, London, Ontario, Canada
| | - Ajay Rajaram
- Lawson Health Research Institute, Imaging Program, London, Ontario, Canada
- Western University, Department of Medical Biophysics, London, Ontario, Canada
| | - Keith St. Lawrence
- Lawson Health Research Institute, Imaging Program, London, Ontario, Canada
- Western University, Department of Medical Biophysics, London, Ontario, Canada
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17
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Cavayas YA, Munshi L, Del Sorbo L, Fan E. The Early Change in Pa CO2 after Extracorporeal Membrane Oxygenation Initiation Is Associated with Neurological Complications. Am J Respir Crit Care Med 2020; 201:1525-1535. [PMID: 32251606 DOI: 10.1164/rccm.202001-0023oc] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Rationale: Large decreases in PaCO2 that occur when initiating extracorporeal membrane oxygenation (ECMO) in patients with respiratory failure may cause cerebral vasoconstriction and compromise brain tissue perfusion.Objectives: To determine if the magnitude of PaCO2 correction upon ECMO initiation is associated with an increased incidence of neurological complications in patients with respiratory failure.Methods: We conducted a multicenter, international, retrospective cohort study using the Extracorporeal Life Support Organization Registry, including adults with respiratory failure receiving ECMO via any mode between 2012 and 2017. The relative change in PaCO2 in the first 24 hours was calculated as (24-h post-ECMO PaCO2 - pre-ECMO PaCO2)/pre-ECMO PaCO2. The primary outcome was the occurrence of neurological complications, defined as seizures, ischemic stroke, intracranial hemorrhage, or brain death.Measurements and Main Results: We included 11,972 patients, 88% of whom were supported with venovenous ECMO. The median relative change in PaCO2 was -31% (interquartile range, -46% to -12%). Neurological complications were uncommon overall (6.9%), with a low incidence of seizures (1.1%), ischemic stroke (1.9%), intracranial hemorrhage (3.5%), and brain death (1.6%). Patients with a large relative decrease in PaCO2 (>50%) had an increased incidence of neurological complications compared with those with a smaller decrease (9.8% vs. 6.4%; P < 0.001). A large relative decrease in PaCO2 was independently associated with neurological complications after controlling for previously described risk factors (odds ratio, 1.7; 95% confidence interval, 1.3 to 2.3; P < 0.001).Conclusions: In patients receiving ECMO for respiratory failure, a large relative decrease in PaCO2 in the first 24 hours after ECMO initiation is independently associated with an increased incidence of neurological complications.
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Affiliation(s)
- Yiorgos Alexandros Cavayas
- Interdepartmental Division of Critical Care Medicine, Toronto General Hospital, and.,Département de Médecine, Hôpital du Sacré-Coeur de Montréal, and.,Département de Chirurgie, Institut de Cardiologie de Montréal, Université de Montréal, Montreal, Quebec, Canada
| | - Laveena Munshi
- Interdepartmental Division of Critical Care Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada; and
| | - Lorenzo Del Sorbo
- Interdepartmental Division of Critical Care Medicine, Toronto General Hospital, and
| | - Eddy Fan
- Interdepartmental Division of Critical Care Medicine, Toronto General Hospital, and
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18
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Velasco Gonzalez A, Schülke C, Buerke B. Uni-hemispheric hyperperfusion in the early postictal state: case report. BMC Neurol 2020; 20:108. [PMID: 32209081 PMCID: PMC7093958 DOI: 10.1186/s12883-020-01665-9] [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: 10/29/2019] [Accepted: 02/28/2020] [Indexed: 11/16/2022] Open
Abstract
Background In the emergency setting of acute ischemic stroke, seizures have been reported in up to 4% of patients. In the absence of arterial occlusion, seizures may also cause abnormalities in CT perfusion in 78% of cases when the time window from onset to imaging is short. Both hyperperfusion and hypoperfusion in the postictal state have been described. Also, though rarely reported, postictal perfusion changes can be uni-hemispheric. In these cases, perfusion maps should be analyzed thoroughly, since perfusion reconstruction software relies heavily on a “normal” contralateral perfusion status. Case presentation A 39-year-old man was found on the ground with a minor head injury. On admission, his reactions were generally slow, but there were no other neurological symptoms, and blood pressure was low. The patient had a history of primary generalized epilepsy and admitted to dropping off his anti-epileptic medication. He was transferred to the radiological department for imaging but shortly before began to experience generalized onset tonic-clonic seizures which were brought under control by intravenous therapy with 10 mg diazepam. After approximately 15 min, a multimodal CT scan was performed, revealing marked changes in the perfusion of the brain hemispheres and posterior fossa, with sharp delimitation at the midline. Blood gas analysis was congruent with respiratory acidosis. Clinically, the patient remained awake without developing any new symptoms. He gradually recovered over the following 3 h and, against our medical recommendation, discharged himself from the hospital. Conclusions To the authors’ knowledge, this is the first report of an early postictal state describing sharply delimited uni-hemispheric hyperperfusion and hemispheric alteration of the cerebellum with an equally split rhombencephalon. Surprisingly, these changes were not associated with any focal neurological signs. To prevent misdiagnosis of perfusion alterations in seizures, radiologists and neurologists should be aware of the limitations of CT perfusion maps and software reconstructions. Novel use of CT perfusion reconstruction using peak enhancement helped in identifying the cerebral pathology.
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Affiliation(s)
- A Velasco Gonzalez
- Department of Clinical Radiology and Neuroradiology, University Hospital Muenster, Albert-Schweitzer-Campus 1, Building A1, 48149, Muenster, Germany.
| | - C Schülke
- Department of Clinical Radiology, University Hospital Muenster, Albert-Schweitzer-Campus 1, Gebäude A1, 48149, Muenster, Germany
| | - B Buerke
- Department of Clinical Radiology and Neuroradiology, University Hospital Muenster, Albert-Schweitzer-Campus 1, Building A1, 48149, Muenster, Germany
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19
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The Organ-Protective Effect of Higher Partial Pressure of Arterial Carbon Dioxide in the Normal Range for Infant Patients Undergoing Ventricular Septal Defect Repair. Pediatr Cardiol 2020; 41:372-381. [PMID: 31844927 DOI: 10.1007/s00246-019-02269-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 12/07/2019] [Indexed: 10/25/2022]
Abstract
Hypercapnia has been reported to play an active role in protection against organ injury. The aim of this study was to determine whether a higher level of partial pressure of arterial carbon dioxide (PaCO2) within the normal range in pediatric patients undergoing cardiac surgery had a similar organ-protective effect. From May 2017 to May 2018, 83 consecutive infant patients undergoing ventricular septal defect (VSD) repair with cardiopulmonary bypass were retrospectively enrolled. We recorded the end-expiratory tidal partial pressure of carbon dioxide (Pet-CO2) as an indirect and continuous way to reflect the PaCO2. The patients were divided into a low PaCO2 group (LPG; 30 mmHg < Pet-CO2 < 40 mmHg) and a high PaCO2 group (HPG; 40 mmHg < Pet-CO2 < 50 mmHg). The regional cerebral oxygen saturation (rScO2), cerebral blood flow velocity (CBFV), and hemodynamics at five time points throughout the operation, and perioperative data were recorded and analyzed for the two groups. In total, 34 LPG and 49 HPG patients were included. Demographics and perioperative clinical data showed no significant difference between the groups. Compared with LPG, the HPG produced lower postoperative creatine kinase isoenzyme-MB (40.88 versus 50.34 ng/mL, P = 0.038). The postoperative C-reactive protein of HPG trended lower than in LPG (61.09 versus 73.4 mg/L, P = 0.056). The rScO2 and mean CBFV of HPG were significantly higher compared with LPG (P < 0.05) except at the end of cardiopulmonary bypass. Hemodynamic data showed no significant difference between the groups. As a convenient and safe approach, higher-normal PaCO2 could attenuate brain injury, heart injury, and inflammatory response in infant patients undergoing VSD repair.
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20
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Sohn B, Park S, Lee HJ, Jeong JH, Choi SM, Lee SM, Seo JH, Kim YT. Cardiopulmonary Bypass Strategies to Maintain Brain Perfusion during Lung Transplantation in a Patient with Severe Hypercapnia. THE KOREAN JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY 2019; 52:58-60. [PMID: 30834222 PMCID: PMC6383849 DOI: 10.5090/kjtcs.2019.52.1.58] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 11/04/2018] [Accepted: 11/05/2018] [Indexed: 11/16/2022]
Abstract
Herein, we report a case of lung transplantation in a patient with profound preoperative hypercapnia, focusing on the cardiopulmonary bypass strategy used for brain perfusion during the operation. We applied the pH-stat method for acid-base regulation, and thereby achieved the desired outcome without any neurologic deficit.
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Affiliation(s)
- Bongyeon Sohn
- Department of Thoracic and Cardiovascular Surgery, Seoul National University Hospital, Seoul National University College of Medicine
| | - Samina Park
- Department of Thoracic and Cardiovascular Surgery, Seoul National University Hospital, Seoul National University College of Medicine
| | - Hyun Joo Lee
- Department of Thoracic and Cardiovascular Surgery, Seoul National University Hospital, Seoul National University College of Medicine
| | - Jin Hee Jeong
- Department of Thoracic and Cardiovascular Surgery, Seoul National University Hospital, Seoul National University College of Medicine
| | - Sun Mi Choi
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University Hospital, Seoul National University College of Medicine
| | - Sang-Min Lee
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University Hospital, Seoul National University College of Medicine
| | - Jeong-Hwa Seo
- Department of Anaesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine
| | - Young Tae Kim
- Department of Thoracic and Cardiovascular Surgery, Seoul National University Hospital, Seoul National University College of Medicine
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21
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Fuglsang CH, Johansen T, Kaila K, Kasch H, Bach FW. Treatment of acute migraine by a partial rebreathing device: A randomized controlled pilot study. Cephalalgia 2018; 38:1632-1643. [PMID: 30134739 PMCID: PMC6158684 DOI: 10.1177/0333102418797285] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Background Impaired brain oxygen delivery can trigger and exacerbate migraine attacks. Normoxic hypercapnia increases brain oxygen delivery markedly by vasodilation of the cerebral vasculature, and hypercapnia has been shown to abort migraine attacks. Stable normoxic hypercapnia can be induced by a compact partial rebreathing device. This pilot study aimed to provide initial data on the device's efficacy and safety. Methods Using a double-blinded, randomized, cross-over study design, adult migraine-with-aura patients self-administered the partial rebreathing device or a sham device for 20 minutes at the onset of aura symptoms. Results Eleven participants (mean age 35.5, three men) self-treated 41 migraine attacks (20 with the partial rebreathing device, 21 with sham). The partial rebreathing device increased mean End Tidal CO2 by 24%, while retaining mean oxygen saturation above 97%. The primary end point (headache intensity difference between first aura symptoms and two hours after treatment (0-3 scale) - active/sham difference) did not reach statistical significance (-0.55 (95% CI: -1.13-0.04), p = 0.096), whereas the difference in percentage of attacks with pain relief at two hours was significant ( p = 0.043), as was user satisfaction ( p = 0.022). A marked efficacy increase was seen from first to second time use of the partial rebreathing device. No adverse events occurred, and side effects were absent or mild. Conclusion Normoxic hypercapnia shows promise as an adjunctive/alternative migraine treatment, meriting further investigation in a larger population. Clinical study registered at ClinicalTrials.gov with identifier NCT03472417.
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Affiliation(s)
| | - Troels Johansen
- 2 Aarhus University School of Engineering, Aarhus University, Aarhus, Denmark.,3 BalancAir, Kongens Lyngby, Denmark
| | - Kai Kaila
- 4 Molecular and Integrative Biosciences Research Program and HiLife, University of Helsinki, Helsinki, Finland
| | - Helge Kasch
- 5 Spinal Cord Injury Center of Western Denmark, Department of Neurology, Regional Hospital of Viborg, Viborg, Denmark
| | - Flemming W Bach
- 1 Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
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22
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Does prolonged severe hypercapnia interfere with normal cerebrovascular function in piglets? Pediatr Res 2018; 84:290-295. [PMID: 29907849 PMCID: PMC6185793 DOI: 10.1038/s41390-018-0061-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 04/16/2018] [Accepted: 04/17/2018] [Indexed: 11/21/2022]
Abstract
BACKGROUND Hypercapnia causes cerebral vasodilation and increased cerebral blood flow (CBF). During prolonged hypercapnia it is unknown whether cerebral vasodilation persists and whether cerebrovascular function is preserved. We investigated the effects of prolonged severe hypercapnia on pial arteriolar diameters (PAD) and cerebrovascular reactivity to vasodilators and vasoconstrictors. METHODS Piglets were anesthetized, intubated and ventilated. Closed cranial windows were implanted to measure PAD. Changes in PAD were documented during hypercapnia (PaCO2 75-80 mm Hg). Cerebrovascular reactivity was documented during normocapnia and at 30, 60, and 120 min of hypercapnia. RESULTS Cerebral vasodilation to hypercapnia was sustained over 120 min. Cerebrovascular responses to vasodilators and vasoconstrictors were preserved during hypercapnia. During hypercapnia, vasodilatory responses to second vasodilators were similar to normocapnia, while exposure to vasoconstrictors caused significant vasoconstriction. CONCLUSIONS Prolonged severe hypercapnia causes sustained vasodilation of pial arteriolar diameters indicative of hyperperfusion. During hypercapnia, cerebral vascular responses to vasodilators and vasoconstrictors were preserved, suggesting that cerebral vascular function remained intact. Of note, cerebral vessels during hypercapnia were capable of further dilation when exposed to additional cerebral vasodilators and, significant vasoconstriction when exposed to vasoconstrictors. Extrapolating these findings to infants, we suggest that severe hypercapnia should be avoided, because it could cause/increase cerebrovascular injury.
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23
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Mishra V, Sreenivasan K, Banks SJ, Zhuang X, Yang Z, Cordes D, Bernick C. Investigating structural and perfusion deficits due to repeated head trauma in active professional fighters. NEUROIMAGE-CLINICAL 2017; 17:616-627. [PMID: 29234598 PMCID: PMC5716952 DOI: 10.1016/j.nicl.2017.11.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 11/13/2017] [Accepted: 11/14/2017] [Indexed: 12/14/2022]
Abstract
Repeated head trauma experienced by active professional fighters results in various structural, functional and perfusion damage. However, whether there are common regions of structural and perfusion damage due to fighting and whether these structural and perfusion differences are associated with neuropsychological measurements in active professional fighters is still unknown. To that end, T1-weighted and pseudocontinuous arterial spin labeling MRI on a group of healthy controls and active professional fighters were acquired. Voxelwise group comparisons, in a univariate and multivariate sense, were performed to investigate differences in gray and white matter density (GMD, WMD) and cerebral blood flow (CBF) between the two groups. A significantly positive association between global GMD and WMD was obtained with psychomotor speed and reaction time, respectively, in our cohort of active professional fighters. In addition, regional WMD deficit was observed in a cluster encompassing bilateral pons, hippocampus, and thalamus in fighters (0.49 ± 0.04 arbitrary units (a.u.)) as compared to controls (0.51 ± 0.05a.u.). WMD in the cluster of active fighters was also significantly associated with reaction time. Significantly lower CBF was observed in right inferior temporal lobe with both partial volume corrected (46.9 ± 14.93 ml/100 g/min) and non-partial volume corrected CBF maps (25.91 ± 7.99 ml/100 g/min) in professional fighters, as compared to controls (65.45 ± 22.24 ml/100 g/min and 35.22 ± 12.18 ml/100 g/min respectively). A paradoxical increase in CBF accompanying right cerebellum and fusiform gyrus in the active professional fighters (29.52 ± 13.03 ml/100 g/min) as compared to controls (19.43 ± 12.56 ml/100 g/min) was observed with non-partial volume corrected CBF maps. Multivariate analysis with both structural and perfusion measurements found the same clusters as univariate analysis in addition to a cluster in right precuneus. Both partial volume corrected and non-partial volume corrected CBF of the cluster in the thalamus had a significantly positive association with the number of fights. In addition, GMD of the cluster in right precuneus was significantly associated with psychomotor speed in our cohort of active professional fighters. Our results suggest a heterogeneous pattern of structural and CBF deficits due to repeated head trauma in active professional fighters. This finding indicates that investigating both structural and CBF changes in the same set of participants may help to understand the pathophysiology and progression of cognitive decline due to repeated head trauma. Repetitive head trauma revealed no global structural or global perfusion deficits. Cluster of significantly lower WMD was associated with reaction time in fighters. Fighters had lower CBF in right inferior temporal lobe. Multivariate analysis revealed a cluster associated with number of fights. Combined analysis of structural and perfusion measurements is recommended.
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Affiliation(s)
- Virendra Mishra
- Lou Ruvo Center for Brain Health, Cleveland Clinic Foundation, Las Vegas, NV, United States.
| | - Karthik Sreenivasan
- Lou Ruvo Center for Brain Health, Cleveland Clinic Foundation, Las Vegas, NV, United States
| | - Sarah J Banks
- Lou Ruvo Center for Brain Health, Cleveland Clinic Foundation, Las Vegas, NV, United States
| | - Xiaowei Zhuang
- Lou Ruvo Center for Brain Health, Cleveland Clinic Foundation, Las Vegas, NV, United States
| | - Zhengshi Yang
- Lou Ruvo Center for Brain Health, Cleveland Clinic Foundation, Las Vegas, NV, United States
| | - Dietmar Cordes
- Lou Ruvo Center for Brain Health, Cleveland Clinic Foundation, Las Vegas, NV, United States
| | - Charles Bernick
- Lou Ruvo Center for Brain Health, Cleveland Clinic Foundation, Las Vegas, NV, United States
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Chaudhary S, Wahab A, Varghese S, Smith SJ. Hypercapnia-induced cerebral oedema in a patient with COPD exacerbation: a rare and under-recognised entity. BMJ Case Rep 2017; 2017:bcr-2017-221568. [PMID: 28801335 DOI: 10.1136/bcr-2017-221568] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Siddique Chaudhary
- Department of Internal Medicine, McLaren Regional Medical Center, Flint, Michigan, USA
| | - Ahsan Wahab
- Department of Internal Medicine, McLaren Regional Medical Center, Flint, Michigan, USA
| | - Shiny Varghese
- Department of Internal Medicine, McLaren Regional Medical Center, Flint, Michigan, USA
| | - Susan Jane Smith
- Department of Internal Medicine, McLaren-Flint Health Care Center/Michigan State University, Flint, Michigan, USA
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25
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Lin L, Metherel AH, Jones PJ, Bazinet RP. Fatty acid amide hydrolase (FAAH) regulates hypercapnia/ischemia-induced increases in n-acylethanolamines in mouse brain. J Neurochem 2017; 142:662-671. [DOI: 10.1111/jnc.14067] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 04/24/2017] [Accepted: 04/26/2017] [Indexed: 01/04/2023]
Affiliation(s)
- Lin Lin
- Department of Nutritional Sciences; University of Toronto; Toronto Canada
| | - Adam H. Metherel
- Department of Nutritional Sciences; University of Toronto; Toronto Canada
| | - Peter J. Jones
- Department of Human Nutritional Sciences; University of Manitoba; Winnipeg Canada
| | - Richard P. Bazinet
- Department of Nutritional Sciences; University of Toronto; Toronto Canada
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Urback AL, MacIntosh BJ, Goldstein BI. Cerebrovascular reactivity measured by functional magnetic resonance imaging during breath-hold challenge: A systematic review. Neurosci Biobehav Rev 2017; 79:27-47. [PMID: 28487157 DOI: 10.1016/j.neubiorev.2017.05.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 04/05/2017] [Accepted: 05/02/2017] [Indexed: 10/19/2022]
Abstract
Cerebrovascular reactivity (CVR) is the cerebral hemodynamic response to a vasoactive substance. Breath-hold (BH) induced CVR has the advantage of being non-invasive and easy to implement during magnetic resonance imaging (MRI). We systematically reviewed the literature regarding MRI measurement of BH induced CVR. The literature was searched using MEDLINE with the search terms breath-hold; and MRI or cerebrovascular reactivity. The search yielded 2244 results and 54 articles were included. Between-group comparisons have found that CVR was higher among healthy controls than patients with various pathologies (e.g. sleep apnea, diabetes, hypertension etc.). However, counter-intuitive findings have also been reported, including higher CVR among smokers, sedentary individuals, and patients with schizophrenia vs. CONTROLS Methodological studies have highlighted important measurement characteristics (e.g. normalizing signal to end-tidal CO2), and comparisons of BH induced CVR to non-BH methods. Future studies are warranted to address questions about group differences, treatment response, disease progression, and other salient clinical themes. Standardization of CVR and BH designs is needed to fully exploit the potential of this practical non-invasive method.
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Affiliation(s)
- Adam L Urback
- Centre for Youth Bipolar Disorder, Sunnybrook Health Sciences Centre 2075 Bayview Ave., FG-53, Toronto, ON, M4N 3M5, Canada; Department of Pharmacology, University of Toronto, Medicine, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada.
| | - Bradley J MacIntosh
- University of Toronto, Department of Medical Biophysics, 101 College Street Suite 15-701, Toronto, ON, M5G 1L7, Canada; Canadian Partnership for Stroke Recovery, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Room M6 180, Toronto, ON, M4N 3M5, Canada.
| | - Benjamin I Goldstein
- Centre for Youth Bipolar Disorder, Sunnybrook Health Sciences Centre 2075 Bayview Ave., FG-53, Toronto, ON, M4N 3M5, Canada; Department of Pharmacology, University of Toronto, Medicine, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada; Department of Psychiatry, University of Toronto, Medicine,250 College Street, Room 835, Toronto, ON, M5T 1R8, Canada.
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Lee JK, Poretti A, Perin J, Huisman TAGM, Parkinson C, Chavez-Valdez R, O'Connor M, Reyes M, Armstrong J, Jennings JM, Gilmore MM, Koehler RC, Northington FJ, Tekes A. Optimizing Cerebral Autoregulation May Decrease Neonatal Regional Hypoxic-Ischemic Brain Injury. Dev Neurosci 2016; 39:248-256. [PMID: 27978510 DOI: 10.1159/000452833] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 10/24/2016] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Therapeutic hypothermia provides incomplete neuroprotection for neonatal hypoxic-ischemic encephalopathy (HIE). We examined whether hemodynamic goals that support autoregulation are associated with decreased brain injury and whether these relationships are affected by birth asphyxia or vary by anatomic region. METHODS Neonates cooled for HIE received near-infrared spectroscopy autoregulation monitoring to identify the mean arterial blood pressure with optimized autoregulatory function (MAPOPT). Blood pressure deviation from MAPOPT was correlated with brain injury on MRI after adjusting for the effects of arterial carbon dioxide, vasopressors, seizures, and birth asphyxia severity. RESULTS Blood pressure deviation from MAPOPT related to neurologic injury in several regions independent of birth asphyxia severity. Greater duration and deviation of blood pressure below MAPOPT were associated with greater injury in the paracentral gyri and white matter. Blood pressure within MAPOPT related to lesser injury in the white matter, putamen and globus pallidus, and brain stem. Finally, blood pressures that exceeded MAPOPT were associated with reduced injury in the paracentral gyri. CONCLUSIONS Blood pressure deviation from optimal autoregulatory vasoreactivity was associated with MRI markers of brain injury that, in many regions, were independent of the initial birth asphyxia. Targeting hemodynamic ranges to optimize autoregulation has potential as an adjunctive therapy to hypothermia for HIE.
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Affiliation(s)
- Jennifer K Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
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Schnitzler S, Kopitz J, Plaschke K. Increased hippocampal CD38 and systemic inflammation after partial hepatectomy does not induce impairment of spatial cognition. Neurol Res 2016; 38:973-980. [DOI: 10.1080/01616412.2016.1242452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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29
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Welch TL, Pasternak JJ. The Anesthetic Management of Interventional Procedures for Acute Ischemic Stroke. CURRENT ANESTHESIOLOGY REPORTS 2016. [DOI: 10.1007/s40140-016-0166-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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30
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Bellucci B, Qiao R. A 47-year-old woman with hypercapnia and altered mental status. CLINICAL RESPIRATORY JOURNAL 2016; 12:331-333. [PMID: 27216321 DOI: 10.1111/crj.12498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 05/12/2016] [Indexed: 11/30/2022]
Abstract
Permissive hypercapnia is a commonly used ventilator strategy in attempt to improve refractory hypoxemia. The rationale of such practice is based on the assumption that hypercapnia, although associated with altered mental status, is well tolerated. Here, we report a case in which the altered mental status caused by hypercapnia is underlined by a life-threatening mechanism. The case indicates the severity of hypercapnia may have been mistakenly overlooked in the past.
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Affiliation(s)
- Brian Bellucci
- Division of Pulmonary, Critical Care, and Sleep Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Renli Qiao
- Division of Pulmonary, Critical Care, and Sleep Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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Yang H, Xiang P, Zhang E, Guo W, Shi Y, Zhang S, Tong Z. Is hypercapnia associated with poor prognosis in chronic obstructive pulmonary disease? A long-term follow-up cohort study. BMJ Open 2015; 5:e008909. [PMID: 26671953 PMCID: PMC4679936 DOI: 10.1136/bmjopen-2015-008909] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVES To assess whether hypercapnia may predict the prognosis in chronic obstructive pulmonary disease (COPD). DESIGN Prospective cohort study comparing the survival of patients with COPD and normocapnia to those with chronic hypercapnia. SETTING Patients with consecutive COPD were enrolled between 1 May 1993 and 31 October 2006 at two medical centres. Follow-up was censored on 31 October 2011. PARTICIPANTS A total of 275 patients with stable COPD and aged 40-85 years were enrolled. Diagnosis of hypercapnia was confirmed by blood gas analysis. Patients with near-terminal illness or comorbidities that affect PaCO2 (obstructive sleep apnoea, obesity-related hypoventilation, or neuromuscular disease) were excluded. The outcome of 98 patients with normocapnia and 177 with chronic hypercapnia was analysed. OUTCOME MEASURES Overall survival. RESULTS Median survival was longer in patients with normocapnia than in those with hypercapnia (6.5 vs 5.0 years, p=0.016). Multivariate COX regression analysis indicated that age (HR=1.043, 95% CI 1.012 to 1.076), Charlson Index, which is a measure of comorbidity (HR=1.172, 95% CI 1.067 to 1.288), use of medication (HR=0.565, 95% CI 0.379 to 0.842), body mass index (BMI) (HR=0.922, 95% CI 0.883 to 0.963), PaCO2 (HR=1.026, 95% CI 1.011 to 1.042), Cor pulmonale (HR=2.164, 95% CI 1.557 to 3.006), non-invasive positive-pressure ventilation (NPPV) (HR=0.615, 95% CI 0.429 to 0.881) and per cent of forced expiratory volume in 1 s (FEV1%) (HR=0.979, 95% CI 0.967 to 0.991), were independent risk factors for mortality. CONCLUSIONS Increased age, Charlson Index, chronic hypercapnia and Cor pulmonale, and decreased FEV1%, use of medication, BMI and NPPV, were associated with a poor prognosis in patients with COPD.
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Affiliation(s)
- Hui Yang
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine, Beijing Chao-Yang Hospital Beijing, Capital Medical University, Beijing, China
- Department of Respiratory and Critical Care Medicine, Shou-Gang Hospital Affiliated to Peking University, Beijing, China
| | - Pingchao Xiang
- Department of Respiratory and Critical Care Medicine, Shou-Gang Hospital Affiliated to Peking University, Beijing, China
| | - Erming Zhang
- Department of Respiratory and Critical Care Medicine, Shou-Gang Hospital Affiliated to Peking University, Beijing, China
| | - Weian Guo
- Department of Respiratory and Critical Care Medicine, Shou-Gang Hospital Affiliated to Peking University, Beijing, China
| | - Yanwei Shi
- Department of Respiratory and Critical Care Medicine, Shou-Gang Hospital Affiliated to Peking University, Beijing, China
| | - Shuo Zhang
- Department of Respiratory and Critical Care Medicine, Shou-Gang Hospital Affiliated to Peking University, Beijing, China
| | - Zhaohui Tong
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine, Beijing Chao-Yang Hospital Beijing, Capital Medical University, Beijing, China
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Chawla S, Ge Y, Lu H, Marshall O, Davitz MS, Fatterpekar G, Soher BJ, Gonen O. Whole-Brain N-Acetylaspartate Concentration Is Preserved during Mild Hypercapnia Challenge. AJNR Am J Neuroradiol 2015; 36:2055-61. [PMID: 26294651 PMCID: PMC4644678 DOI: 10.3174/ajnr.a4424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 04/01/2015] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Although NAA is often used as a marker of neuronal health and integrity in neurologic disorders, its normal response to physiologic challenge is not well-established and its changes are almost always attributed exclusively to brain pathology. The purpose of this study was to test the hypothesis that the neuronal cell marker NAA, often used to assess neuronal health and integrity in neurologic disorders, is not confounded by (possibly transient) physiologic changes. Therefore, its decline, when observed by using (1)H-MR spectroscopy, can almost always be attributed exclusively to brain pathology. MATERIALS AND METHODS Twelve healthy young male adults underwent a transient hypercapnia challenge (breathing 5% CO2 air mixture), a potent vasodilator known to cause a substantial increase in CBF and venous oxygenation. We evaluated their whole-brain NAA by using nonlocalizing proton MR spectroscopy, venous oxygenation with T2-relaxation under spin-tagging MR imaging, CBF with pseudocontinuous arterial spin-labeling, and the cerebral metabolic rate of oxygen, during normocapnia (breathing room air) and hypercapnia. RESULTS There was insignificant whole-brain NAA change (P = .88) from normocapnia to hypercapnia and back to normocapnia in this cohort, as opposed to highly significant increases: 28.0 ± 10.3% in venous oxygenation and 49.7 ± 16.6% in global CBF (P < 10(-4)); and a 6.4 ± 10.9% decrease in the global cerebral metabolic rate of oxygen (P = .04). CONCLUSIONS Stable whole-brain NAA during normocapnia and hypercapnia, despite significant global CBF and cerebral metabolic rate of oxygen changes, supports the hypothesis that global NAA changes are insensitive to transient physiology. Therefore, when observed, they most likely reflect underlying pathology resulting from neuronal cell integrity/viability changes, instead of a response to physiologic changes.
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Affiliation(s)
- S Chawla
- From the Department of Radiology (S.C., Y.G., O.M., M.S.D., G.F., O.G.), Center for Advanced Imaging Innovation and Research and Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, New York
| | - Y Ge
- From the Department of Radiology (S.C., Y.G., O.M., M.S.D., G.F., O.G.), Center for Advanced Imaging Innovation and Research and Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, New York
| | - H Lu
- The Russell H. Morgan Department of Radiology and Radiological Science (H.L.), Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - O Marshall
- From the Department of Radiology (S.C., Y.G., O.M., M.S.D., G.F., O.G.), Center for Advanced Imaging Innovation and Research and Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, New York
| | - M S Davitz
- From the Department of Radiology (S.C., Y.G., O.M., M.S.D., G.F., O.G.), Center for Advanced Imaging Innovation and Research and Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, New York
| | - G Fatterpekar
- From the Department of Radiology (S.C., Y.G., O.M., M.S.D., G.F., O.G.), Center for Advanced Imaging Innovation and Research and Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, New York
| | - B J Soher
- Department of Radiology (B.J.S.), Center for Advanced MR Development, Duke University Medical Center, Durham, North Carolina
| | - O Gonen
- From the Department of Radiology (S.C., Y.G., O.M., M.S.D., G.F., O.G.), Center for Advanced Imaging Innovation and Research and Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, New York
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Thoracoscopic versus open repair of CDH in cardiovascular stable neonates. Surg Endosc 2015; 30:2818-24. [PMID: 26490767 PMCID: PMC4912591 DOI: 10.1007/s00464-015-4560-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 09/04/2015] [Indexed: 11/17/2022]
Abstract
Background Thoracoscopic surgery is an increasingly popular surgical technique to repair congenital diaphragmatic hernia (CDH). However, acidosis during surgery and the higher recurrence rate are considerable risk factors. The aim of this retrospective study is to compare the outcome of open versus thoracoscopic repair of the diaphragm in neonates with CDH with the same degree of cardiovascular and pulmonary illness who meet the criteria for thoracoscopic repair. Methods Retrospective analysis of all patients of two large national reference centers for CDH born in the years 2008 through 2012, and meeting the criteria for surgical repair on cardiopulmonary and physiological criteria according to the CDH EURO consortium consensus and meeting the criteria for thoracoscopic repair according to the review by Vijfhuize et al. The surgical technical aspects were comparable in both centers. Results 108 patients were included, of whom 75 underwent thoracoscopic repair and 34 underwent open repair. The gestational age and lung-to-head ratio were significantly lower and stay on the ICU significantly longer in the open-repair group. The operation time was longer (178 vs. 150 min, p = .012) and the recurrence rate higher (18.9 vs. 5.9 %, p = .036) in the thoracoscopic-repair group. The arterial pH, pO2, pCO2 and base excess before and after thoracoscopic repair were all significantly different. Conclusion After critical selection for thoracoscopic repair of left-sided CDH based on the patient’s preoperative condition, the outcomes of open repair were almost identical to those of thoracoscopic repair. A notable exception is the recurrence rate, which was significantly higher in the thoracoscopic-repair group. For the time being, thoracoscopic primary closure seems a safe and effective procedure, but efficacy of thoracoscopic patch repair has not been established.
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Burton VJ, Gerner G, Cristofalo E, Chung SE, Jennings JM, Parkinson C, Koehler RC, Chavez-Valdez R, Johnston MV, Northington FJ, Lee JK. A pilot cohort study of cerebral autoregulation and 2-year neurodevelopmental outcomes in neonates with hypoxic-ischemic encephalopathy who received therapeutic hypothermia. BMC Neurol 2015; 15:209. [PMID: 26486728 PMCID: PMC4618147 DOI: 10.1186/s12883-015-0464-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 10/06/2015] [Indexed: 11/17/2022] Open
Abstract
Background Neurodevelopmental disabilities persist in survivors of neonatal hypoxic-ischemic encephalopathy (HIE) despite treatment with therapeutic hypothermia. Cerebrovascular autoregulation, the mechanism that maintains cerebral perfusion during changes in blood pressure, may influence outcomes. Our objective was to describe the relationship between acute autoregulatory vasoreactivity during treatment and neurodevelopmental outcomes at 2 years of age. Methods In a pilot study of 28 neonates with HIE, we measured cerebral autoregulatory vasoreactivity with the hemoglobin volume index (HVx) during therapeutic hypothermia, rewarming, and the first 6 h of normothermia. The HVx, which is derived from near-infrared spectroscopy, was used to identify the individual optimal mean arterial blood pressure (MAPOPT) at which autoregulatory vasoreactivity is greatest. Cognitive and motor neurodevelopmental evaluations were completed in 19 children at 21–32 months of age. MAPOPT, blood pressure in relation to MAPOPT, blood pressure below gestational age + 5 (ga + 5), and regional cerebral oximetry (rSO2) were compared to the neurodevelopmental outcomes. Results Nineteen children who had HIE and were treated with therapeutic hypothermia performed in the average range on cognitive and motor evaluations at 21–32 months of age, although the mean performance was lower than that of published normative samples. Children with impairments at the 2-year evaluation had higher MAPOPT values, spent more time with blood pressure below MAPOPT, and had greater blood pressure deviation below MAPOPT during rewarming in the neonatal period than those without impairments. Greater blood pressure deviation above MAPOPT during rewarming was associated with less disability and higher cognitive scores. No association was observed between rSO2 or blood pressure below ga + 5 and neurodevelopmental outcomes. Conclusion In this pilot cohort, motor and cognitive impairments at 21–32 months of age were associated with greater blood pressure deviation below MAPOPT during rewarming following therapeutic hypothermia, but not with rSO2 or blood pressure below ga + 5. This suggests that identifying individual neonates’ MAPOPT is superior to using hemodynamic goals based on gestational age or rSO2 in the acute management of neonatal HIE. Electronic supplementary material The online version of this article (doi:10.1186/s12883-015-0464-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Vera Joanna Burton
- Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA. .,Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, Johns Hopkins School of Medicine, 801 N Broadway, Baltimore, MD, 21205, USA.
| | - Gwendolyn Gerner
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Department of Neuropsychology, Kennedy Krieger Institute, Baltimore, MD, USA.
| | - Elizabeth Cristofalo
- Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA. .,Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Shang-en Chung
- Center for Child and Community Health Research (CCHR), Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Jacky M Jennings
- Center for Child and Community Health Research (CCHR), Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Charlamaine Parkinson
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Raymond C Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Raul Chavez-Valdez
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Michael V Johnston
- Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA. .,Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Hugo Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA.
| | - Frances J Northington
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Jennifer K Lee
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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Burton VJ, Gerner G, Cristofalo E, Chung SE, Jennings JM, Parkinson C, Koehler RC, Chavez-Valdez R, Johnston MV, Northington FJ, Lee JK. A pilot cohort study of cerebral autoregulation and 2-year neurodevelopmental outcomes in neonates with hypoxic-ischemic encephalopathy who received therapeutic hypothermia. BMC Neurol 2015. [PMID: 26486728 DOI: 10.1186/s12883-015-0464-410.1186/s12883-015-0464-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023] Open
Abstract
BACKGROUND Neurodevelopmental disabilities persist in survivors of neonatal hypoxic-ischemic encephalopathy (HIE) despite treatment with therapeutic hypothermia. Cerebrovascular autoregulation, the mechanism that maintains cerebral perfusion during changes in blood pressure, may influence outcomes. Our objective was to describe the relationship between acute autoregulatory vasoreactivity during treatment and neurodevelopmental outcomes at 2 years of age. METHODS In a pilot study of 28 neonates with HIE, we measured cerebral autoregulatory vasoreactivity with the hemoglobin volume index (HVx) during therapeutic hypothermia, rewarming, and the first 6 h of normothermia. The HVx, which is derived from near-infrared spectroscopy, was used to identify the individual optimal mean arterial blood pressure (MAPOPT) at which autoregulatory vasoreactivity is greatest. Cognitive and motor neurodevelopmental evaluations were completed in 19 children at 21-32 months of age. MAPOPT, blood pressure in relation to MAPOPT, blood pressure below gestational age + 5 (ga + 5), and regional cerebral oximetry (rSO2) were compared to the neurodevelopmental outcomes. RESULTS Nineteen children who had HIE and were treated with therapeutic hypothermia performed in the average range on cognitive and motor evaluations at 21-32 months of age, although the mean performance was lower than that of published normative samples. Children with impairments at the 2-year evaluation had higher MAPOPT values, spent more time with blood pressure below MAPOPT, and had greater blood pressure deviation below MAPOPT during rewarming in the neonatal period than those without impairments. Greater blood pressure deviation above MAPOPT during rewarming was associated with less disability and higher cognitive scores. No association was observed between rSO2 or blood pressure below ga + 5 and neurodevelopmental outcomes. CONCLUSION In this pilot cohort, motor and cognitive impairments at 21-32 months of age were associated with greater blood pressure deviation below MAPOPT during rewarming following therapeutic hypothermia, but not with rSO2 or blood pressure below ga + 5. This suggests that identifying individual neonates' MAPOPT is superior to using hemodynamic goals based on gestational age or rSO2 in the acute management of neonatal HIE.
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Affiliation(s)
- Vera Joanna Burton
- Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA.
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA.
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA.
- Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, Johns Hopkins School of Medicine, 801 N Broadway, Baltimore, MD, 21205, USA.
| | - Gwendolyn Gerner
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA.
- Department of Neuropsychology, Kennedy Krieger Institute, Baltimore, MD, USA.
| | - Elizabeth Cristofalo
- Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA.
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA.
- Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Shang-en Chung
- Center for Child and Community Health Research (CCHR), Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Jacky M Jennings
- Center for Child and Community Health Research (CCHR), Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Charlamaine Parkinson
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA.
- Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Raymond C Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Raul Chavez-Valdez
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA.
- Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Michael V Johnston
- Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA.
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA.
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA.
- Hugo Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA.
| | - Frances J Northington
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA.
- Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Jennifer K Lee
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA.
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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Burton VJ, Gerner G, Cristofalo E, Chung SE, Jennings JM, Parkinson C, Koehler RC, Chavez-Valdez R, Johnston MV, Northington FJ, Lee JK. A pilot cohort study of cerebral autoregulation and 2-year neurodevelopmental outcomes in neonates with hypoxic-ischemic encephalopathy who received therapeutic hypothermia. BMC Neurol 2015. [PMID: 26486728 DOI: 10.1186/s12883‐015‐0464‐4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Neurodevelopmental disabilities persist in survivors of neonatal hypoxic-ischemic encephalopathy (HIE) despite treatment with therapeutic hypothermia. Cerebrovascular autoregulation, the mechanism that maintains cerebral perfusion during changes in blood pressure, may influence outcomes. Our objective was to describe the relationship between acute autoregulatory vasoreactivity during treatment and neurodevelopmental outcomes at 2 years of age. METHODS In a pilot study of 28 neonates with HIE, we measured cerebral autoregulatory vasoreactivity with the hemoglobin volume index (HVx) during therapeutic hypothermia, rewarming, and the first 6 h of normothermia. The HVx, which is derived from near-infrared spectroscopy, was used to identify the individual optimal mean arterial blood pressure (MAPOPT) at which autoregulatory vasoreactivity is greatest. Cognitive and motor neurodevelopmental evaluations were completed in 19 children at 21-32 months of age. MAPOPT, blood pressure in relation to MAPOPT, blood pressure below gestational age + 5 (ga + 5), and regional cerebral oximetry (rSO2) were compared to the neurodevelopmental outcomes. RESULTS Nineteen children who had HIE and were treated with therapeutic hypothermia performed in the average range on cognitive and motor evaluations at 21-32 months of age, although the mean performance was lower than that of published normative samples. Children with impairments at the 2-year evaluation had higher MAPOPT values, spent more time with blood pressure below MAPOPT, and had greater blood pressure deviation below MAPOPT during rewarming in the neonatal period than those without impairments. Greater blood pressure deviation above MAPOPT during rewarming was associated with less disability and higher cognitive scores. No association was observed between rSO2 or blood pressure below ga + 5 and neurodevelopmental outcomes. CONCLUSION In this pilot cohort, motor and cognitive impairments at 21-32 months of age were associated with greater blood pressure deviation below MAPOPT during rewarming following therapeutic hypothermia, but not with rSO2 or blood pressure below ga + 5. This suggests that identifying individual neonates' MAPOPT is superior to using hemodynamic goals based on gestational age or rSO2 in the acute management of neonatal HIE.
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Affiliation(s)
- Vera Joanna Burton
- Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA. .,Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, Johns Hopkins School of Medicine, 801 N Broadway, Baltimore, MD, 21205, USA.
| | - Gwendolyn Gerner
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Department of Neuropsychology, Kennedy Krieger Institute, Baltimore, MD, USA.
| | - Elizabeth Cristofalo
- Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA. .,Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Shang-en Chung
- Center for Child and Community Health Research (CCHR), Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Jacky M Jennings
- Center for Child and Community Health Research (CCHR), Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Charlamaine Parkinson
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Raymond C Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Raul Chavez-Valdez
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Michael V Johnston
- Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA. .,Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Hugo Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA.
| | - Frances J Northington
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Division of Perinatal-Neonatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Jennifer K Lee
- Neurosciences Intensive Care Nursery, Johns Hopkins School of Medicine, Baltimore, MD, USA. .,Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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Zhang P, Shi X, Downey HF. Two-week normobaric intermittent-hypoxic exposures stabilize cerebral perfusion during hypocapnia and hypercapnia. Exp Biol Med (Maywood) 2014; 240:961-8. [PMID: 25504012 DOI: 10.1177/1535370214562339] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 10/14/2014] [Indexed: 11/15/2022] Open
Abstract
The effect of moderately extended, intermittent-hypoxia (IH) on cerebral perfusion during changes in CO2 was unknown. Thus, we assessed the changes in cerebral vascular conductance (CVC) and cerebral tissue oxygenation (ScO2) during experimental hypocapnia and hypercapnia following 14-day normobaric exposures to IH (10% O2). CVC was estimated from the ratio of mean middle cerebral arterial blood flow velocity (transcranial Doppler sonography) to mean arterial pressure (tonometry), and ScO2 in the prefrontal cortex was monitored by near-infrared spectroscopy. Changes in CVC and ScO2 during changes in partial pressure of end-tidal CO2 (PETCO2, mass spectrometry) induced by 30-s paced-hyperventilation (hypocapnia) and during 6-min CO2 rebreathing (hypercapnia) were compared before and after 14-day IH exposures in eight young nonsmokers. Repetitive IH exposures reduced the ratio of %ΔCVC/ΔPETCO2 during hypocapnia (1.00 ± 0.13 vs 1.94 ± 0.35 vs %/mmHg, P = 0.026) and the slope of ΔCVC/ΔPETCO2 during hypercapnia (1.79 ± 0.37 vs 2.97 ± 0.64 %/mmHg, P = 0.021), but had no significant effect on ΔScO2/ΔPETCO2. The ventilatory response to hypercapnia during CO2 rebreathing was significantly diminished following 14-day IH exposures (0.83 ± 0.07 vs 1.14 ± 0.09 L/min/mmHg, P = 0.009). We conclude that repetitive normobaric IH exposures significantly diminish variations of cerebral perfusion in response to hypercapnia and hypocapnia without compromising cerebral tissue oxygenation. This IH-induced blunting of cerebral vasoreactivity during CO2 variations helps buffer excessive oscillations of cerebral underperfusion and overperfusion while sustaining cerebral O2 homeostasis.
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Affiliation(s)
- Peizhen Zhang
- Department of Integrative Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, TX 76107, USA Beijing Sport University, Beijing 100084, China
| | - Xiangrong Shi
- Department of Integrative Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, TX 76107, USA Cardiovascular Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - H Fred Downey
- Department of Integrative Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, TX 76107, USA Cardiovascular Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
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38
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Raffield LM, Cox AJ, Hugenschmidt CE, Freedman BI, Langefeld CD, Williamson JD, Hsu FC, Maldjian JA, Bowden DW. Heritability and genetic association analysis of neuroimaging measures in the Diabetes Heart Study. Neurobiol Aging 2014; 36:1602.e7-15. [PMID: 25523635 DOI: 10.1016/j.neurobiolaging.2014.11.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 11/15/2014] [Indexed: 12/24/2022]
Abstract
Patients with type 2 diabetes are at increased risk of age-related cognitive decline and dementia. Neuroimaging measures such as white matter lesion volume, brain volume, and fractional anisotropy may reflect the pathogenesis of these cognitive declines, and genetic factors may contribute to variability in these measures. This study examined multiple neuroimaging measures in 465 participants from 238 families with extensive genotype data in the type 2 diabetes enriched Diabetes Heart Study-Mind cohort. Heritability of these phenotypes and their association with candidate single-nucleotide polymorphisms (SNPs), and SNP data from genome- and exome-wide arrays were explored. All neuroimaging measures analyzed were significantly heritable (ĥ(2) = 0.55-0.99 in unadjusted models). Seventeen candidate SNPs (from 16 genes/regions) associated with neuroimaging phenotypes in prior studies showed no significant evidence of association. A missense variant (rs150706952, A432V) in PLEKHG4B from the exome-wide array was significantly associated with white matter mean diffusivity (p = 3.66 × 10(-7)) and gray matter mean diffusivity (p = 2.14 × 10(-7)). This analysis suggests genetic factors contribute to variation in neuroimaging measures in a population enriched for metabolic disease and other associated comorbidities.
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Affiliation(s)
- Laura M Raffield
- Molecular Genetics and Genomics Program, Wake Forest School of Medicine, Winston-Salem, NC, USA; Center for Genomics and Personalized Medicine Research, Wake Forest School of Medicine, Winston-Salem, NC, USA; Center for Diabetes Research, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Amanda J Cox
- Center for Genomics and Personalized Medicine Research, Wake Forest School of Medicine, Winston-Salem, NC, USA; Center for Diabetes Research, Wake Forest School of Medicine, Winston-Salem, NC, USA; Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Christina E Hugenschmidt
- Department of Gerontology and Geriatrics, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Barry I Freedman
- Department of Internal Medicine-Nephrology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Carl D Langefeld
- Department of Biostatistical Sciences, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Jeff D Williamson
- Department of Gerontology and Geriatrics, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Fang-Chi Hsu
- Department of Biostatistical Sciences, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Joseph A Maldjian
- Department of Radiology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Donald W Bowden
- Center for Genomics and Personalized Medicine Research, Wake Forest School of Medicine, Winston-Salem, NC, USA; Center for Diabetes Research, Wake Forest School of Medicine, Winston-Salem, NC, USA; Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC, USA.
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39
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Talke PO, Sharma D, Heyer EJ, Bergese SD, Blackham KA, Stevens RD. Republished: Society for Neuroscience in Anesthesiology and Critical Care expert consensus statement: Anesthetic management of endovascular treatment for acute ischemic stroke. Stroke 2014; 45:e138-50. [PMID: 25070964 DOI: 10.1161/strokeaha.113.003412] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Literature on the anesthetic management of endovascular treatment of acute ischemic stroke (AIS) is limited. Anesthetic management during these procedures is still mostly dependent on individual or institutional preferences. Thus, the Society of Neuroscience in Anesthesiology and Critical Care (SNACC) created a task force to provide expert consensus recommendations on anesthetic management of endovascular treatment of AIS. The task force conducted a systematic literature review (up to August 2012). Because of the limited number of research articles relating to this subject, the task force solicited opinions from experts in this area. The task force created a draft consensus statement based on the available data. Classes of recommendations and levels of evidence were assigned to articles specifically addressing anesthetic management during endovascular treatment of stroke using the standard American Heart Association evidence rating scheme. The draft consensus statement was reviewed by the Task Force, SNACC Executive Committee and representatives of Society of NeuroInterventional Surgery (SNIS) and Neurocritical Care Society (NCS) reaching consensus on the final document. For this consensus statement the anesthetic management of endovascular treatment of AIS was subdivided into 12 topics. Each topic includes a summary of available data followed by recommendations. This consensus statement is intended for use by individuals involved in the care of patients with acute ischemic stroke, such as anesthesiologists, interventional neuroradiologists, neurologists, neurointensivists and neurosurgeons.
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Affiliation(s)
- Pekka O Talke
- Department of Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, CA.
| | - Deepak Sharma
- Department of Anesthesiology & Pain Medicine, University of Washington, Seattle, WA
| | - Eric J Heyer
- Departments of Anesthesiology and Neurology, Columbia University, New York, NY
| | - Sergio D Bergese
- Departments of Anesthesiology and Neurological Surgery, The Ohio State University, Columbus (on behalf of Society for Neuroscience in Anesthesiology and Critical Care [SNACC])
| | - Kristine A Blackham
- Department of Radiology, Case Western Reserve University, Cleveland, OH (representing the Society of NeuroInterventional Surgery [SNIS])
| | - Robert D Stevens
- Departments of Anesthesiology Critical Care Medicine, Neurology, Neurosurgery and Radiology, Hopkins University School of Medicine, Baltimore, MD (representing the Neurocritical Care Society [NCS])
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40
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Telischak NA, Detre JA, Zaharchuk G. Arterial spin labeling MRI: clinical applications in the brain. J Magn Reson Imaging 2014; 41:1165-80. [PMID: 25236477 DOI: 10.1002/jmri.24751] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 08/05/2014] [Indexed: 11/05/2022] Open
Abstract
Visualization of cerebral blood flow (CBF) has become an important part of neuroimaging for a wide range of diseases. Arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) sequences are increasingly being used to provide MR-based CBF quantification without the need for contrast administration, and can be obtained in conjunction with a structural MRI study. ASL MRI is useful for evaluating cerebrovascular disease including arterio-occlusive disease, vascular shunts, for assessing primary and secondary malignancy, and as a biomarker for neuronal metabolism in other disorders such as seizures and neurodegeneration. In this review we briefly outline the various ASL techniques including advantages and disadvantages of each, methodology for clinical interpretation, and clinical applications with specific examples.
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Affiliation(s)
- Nicholas A Telischak
- Department of Radiology, Stanford University Medical Center, Stanford, California, USA
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41
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Lee JK, Brady KM, Chung SE, Jennings JM, Whitaker EE, Aganga D, Easley RB, Heitmiller K, Jamrogowicz JL, Larson AC, Lee JH, Jordan LC, Hogue CW, Lehmann CU, Bembea MM, Hunt EA, Koehler RC, Shaffner DH. A pilot study of cerebrovascular reactivity autoregulation after pediatric cardiac arrest. Resuscitation 2014; 85:1387-93. [PMID: 25046743 DOI: 10.1016/j.resuscitation.2014.07.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 06/26/2014] [Accepted: 07/07/2014] [Indexed: 11/17/2022]
Abstract
AIM Improved survival after cardiac arrest has placed greater emphasis on neurologic resuscitation. The purpose of this pilot study was to evaluate the relationship between cerebrovascular autoregulation and neurologic outcomes after pediatric cardiac arrest. METHODS Children resuscitated from cardiac arrest had autoregulation monitoring during the first 72h after return of circulation with an index derived from near-infrared spectroscopy in a pilot study. The range of mean arterial blood pressure (MAP) with optimal vasoreactivity (MAPOPT) was identified. The area under the curve (AUC) of the time spent with MAP below MAPOPT and MAP deviation below MAPOPT was calculated. Neurologic outcome measures included placement of a new tracheostomy or gastrostomy, death from a primary neurologic etiology (brain death or withdrawal of support for neurologic futility), and change in the Pediatric Cerebral Performance Category score (ΔPCPC). RESULTS Thirty-six children were monitored. Among children who did not require extracorporeal membrane oxygenation (ECMO), children who received a tracheostomy/gastrostomy had greater AUC during the second 24h after resuscitation than those who did not (P=0.04; n=19). Children without ECMO who died from a neurologic etiology had greater AUC during the first 48h than did those who lived or died from cardiovascular failure (P=0.04; n=19). AUC below MAPOPT was not associated with ΔPCPC when children with or without ECMO were analyzed separately. CONCLUSIONS Deviation from the blood pressure with optimal autoregulatory vasoreactivity may predict poor neurologic outcomes after pediatric cardiac arrest. This experimental autoregulation monitoring technique may help individualize blood pressure management goals after resuscitation.
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Affiliation(s)
- Jennifer K Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA.
| | - Ken M Brady
- Department of Anesthesiology, Texas Children's Hospital, Houston, TX, USA
| | - Shang-En Chung
- Department of Pediatrics, Division of General Pediatrics and Adolescent Medicine, JHU, USA; Center for Child and Community Health Research, JHU, USA
| | - Jacky M Jennings
- Department of Pediatrics, Division of General Pediatrics and Adolescent Medicine, JHU, USA; Center for Child and Community Health Research, JHU, USA
| | - Emmett E Whitaker
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA
| | - Devon Aganga
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA
| | - Ronald B Easley
- Department of Anesthesiology, Texas Children's Hospital, Houston, TX, USA
| | - Kerry Heitmiller
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA
| | - Jessica L Jamrogowicz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA
| | - Abby C Larson
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA
| | - Jeong-Hoo Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA
| | - Lori C Jordan
- Department of Neurology, Vanderbilt University (VU), Nashville, TN, USA
| | - Charles W Hogue
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA
| | - Christoph U Lehmann
- Department of Pediatrics, VU, USA; Department of Biomedical Informatics, VU, USA
| | - Mela M Bembea
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA
| | - Elizabeth A Hunt
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA
| | - Raymond C Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA
| | - Donald H Shaffner
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University (JHU), Baltimore, MD, USA
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42
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Society for Neuroscience in Anesthesiology and Critical Care Expert Consensus Statement. J Neurosurg Anesthesiol 2014; 26:95-108. [DOI: 10.1097/ana.0000000000000042] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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43
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The intensive care management of acute ischemic stroke: an overview. Intensive Care Med 2014; 40:640-53. [DOI: 10.1007/s00134-014-3266-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 03/11/2014] [Indexed: 01/21/2023]
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Howlett JA, Northington FJ, Gilmore MM, Tekes A, Huisman TA, Parkinson C, Chung SE, Jennings JM, Jamrogowicz JJ, Larson AC, Lehmann CU, Jackson E, Brady KM, Koehler RC, Lee JK. Cerebrovascular autoregulation and neurologic injury in neonatal hypoxic-ischemic encephalopathy. Pediatr Res 2013; 74:525-35. [PMID: 23942555 PMCID: PMC3954983 DOI: 10.1038/pr.2013.132] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 01/31/2013] [Indexed: 12/12/2022]
Abstract
BACKGROUND Neonates with hypoxic-ischemic encephalopathy (HIE) are at risk of cerebral blood flow dysregulation. Our objective was to describe the relationship between autoregulation and neurologic injury in HIE. METHODS Neonates with HIE had autoregulation monitoring with the hemoglobin volume index (HVx) during therapeutic hypothermia, rewarming, and the first 6 h of normothermia. The 5-mm Hg range of mean arterial blood pressure (MAP) with best vasoreactivity (MAPOPT) was identified. The percentage of time spent with MAP below MAPOPT and deviation in MAP from MAPOPT were measured. Neonates received brain magnetic resonance imaging (MRI) 3-7 d after treatment. MRIs were coded as no, mild, or moderate/severe injury in five regions. RESULTS HVx identified MAPOPT in 79% (19/24), 77% (17/22), and 86% (18/21) of the neonates during hypothermia, rewarming, and normothermia, respectively. Neonates with moderate/severe injury in paracentral gyri, white matter, basal ganglia, and thalamus spent a greater proportion of time with MAP below MAPOPT during rewarming than neonates with no or mild injury. Neonates with moderate/severe injury in paracentral gyri, basal ganglia, and thalamus had greater MAP deviation below MAPOPT during rewarming than neonates without injury. CONCLUSION Maintaining MAP within or above MAPOPT may reduce the risk of neurologic injuries in neonatal HIE.
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Affiliation(s)
- Jessica A. Howlett
- Department of Pediatrics, Division of Neonatology, Johns Hopkins University School of Medicine (JHU), Baltimore, MD,Neurosciences Intensive Care Nursery Program, JHU
| | - Frances J. Northington
- Department of Pediatrics, Division of Neonatology, Johns Hopkins University School of Medicine (JHU), Baltimore, MD,Neurosciences Intensive Care Nursery Program, JHU
| | - Maureen M. Gilmore
- Department of Pediatrics, Division of Neonatology, Johns Hopkins University School of Medicine (JHU), Baltimore, MD,Neurosciences Intensive Care Nursery Program, JHU
| | - Aylin Tekes
- Neurosciences Intensive Care Nursery Program, JHU,Department of Radiology, Division of Pediatric Radiology, JHU
| | - Thierry A.G.M. Huisman
- Neurosciences Intensive Care Nursery Program, JHU,Department of Radiology, Division of Pediatric Radiology, JHU
| | - Charlamaine Parkinson
- Department of Pediatrics, Division of Neonatology, Johns Hopkins University School of Medicine (JHU), Baltimore, MD,Neurosciences Intensive Care Nursery Program, JHU
| | - Shang-En Chung
- Department of Pediatrics, Division of General Pediatrics and Adolescent Medicine, JHU,Center for Child and Community Health Research (CCHR), JHU
| | - Jacky M. Jennings
- Department of Pediatrics, Division of General Pediatrics and Adolescent Medicine, JHU,Center for Child and Community Health Research (CCHR), JHU
| | | | - Abby C. Larson
- Department of Anesthesiology and Critical Care Medicine, JHU
| | - Christoph U. Lehmann
- Department of Pediatrics, Division of Neonatology, Johns Hopkins University School of Medicine (JHU), Baltimore, MD
| | - Eric Jackson
- Department of Anesthesiology and Critical Care Medicine, JHU
| | - Ken M. Brady
- Department of Anesthesiology, Texas Children’s Hospital, Houston, TX
| | | | - Jennifer K. Lee
- Neurosciences Intensive Care Nursery Program, JHU,Department of Anesthesiology and Critical Care Medicine, JHU
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Balancing the Potential Risks and Benefits of Out-of-Hospital Intubation in Traumatic Brain Injury: The Intubation/Hyperventilation Effect. Ann Emerg Med 2012; 60:732-6. [DOI: 10.1016/j.annemergmed.2012.06.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 06/11/2012] [Accepted: 06/25/2012] [Indexed: 11/20/2022]
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47
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McGehee BE, Pollock JM, Maldjian JA. Brain perfusion imaging: How does it work and what should I use? J Magn Reson Imaging 2012; 36:1257-72. [DOI: 10.1002/jmri.23645] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Accepted: 02/17/2012] [Indexed: 11/09/2022] Open
Affiliation(s)
- Blake E. McGehee
- Department of Radiology, Wake Forest University School of Medicine, Winston‐Salem, North Carolina, USA
| | - Jeffrey M. Pollock
- Department of Radiology, Oregon Health and Science University, Portland, Oregon, USA
| | - Joseph A. Maldjian
- Department of Radiology, Wake Forest University School of Medicine, Winston‐Salem, North Carolina, USA
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Blinman T, Ponsky T. Pediatric minimally invasive surgery: laparoscopy and thoracoscopy in infants and children. Pediatrics 2012; 130:539-49. [PMID: 22869825 DOI: 10.1542/peds.2011-2812] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
This article discusses the potential benefits and challenges of minimally invasive surgery for infants and small children, and discusses why pediatric minimally invasive surgery is not yet the surgical default or standard of care. Minimally invasive methods offer advantages such as smaller incisions, decreased risk of infection, greater surgical precision, decreased cost of care, reduced length of stay, and better clinical information. But none of these benefits comes without cost, and these costs, both monetary and risk-based, rise disproportionately with the declining size of the patient. In this review, we describe recent progress in minimally invasive surgery for infants and children. The evidence for the large benefits to the patient will be presented, as well as the considerable, sometimes surprising, mechanical and physiological challenges surgeons must manage.
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Affiliation(s)
- Thane Blinman
- Children's Hospital of Philadelphia, 34th and Civic Center, Philadelphia, PA 19083, USA.
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Donahue MJ, Strother MK, Hendrikse J. Novel MRI approaches for assessing cerebral hemodynamics in ischemic cerebrovascular disease. Stroke 2012; 43:903-15. [PMID: 22343644 DOI: 10.1161/strokeaha.111.635995] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Changes in cerebral hemodynamics underlie a broad spectrum of ischemic cerebrovascular disorders. An ability to accurately and quantitatively measure hemodynamic (cerebral blood flow and cerebral blood volume) and related metabolic (cerebral metabolic rate of oxygen) parameters is important for understanding healthy brain function and comparative dysfunction in ischemia. Although positron emission tomography, single-photon emission tomography, and gadolinium-MRI approaches are common, more recently MRI approaches that do not require exogenous contrast have been introduced with variable sensitivity for hemodynamic parameters. The ability to obtain hemodynamic measurements with these new approaches is particularly appealing in clinical and research scenarios in which follow-up and longitudinal studies are necessary. The purpose of this review is to outline current state-of-the-art MRI methods for measuring cerebral blood flow, cerebral blood volume, and cerebral metabolic rate of oxygen and provide practical tips to avoid imaging pitfalls. MRI studies of cerebrovascular disease performed without exogenous contrast are synopsized in the context of clinical relevance and methodological strengths and limitations.
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Affiliation(s)
- Manus J Donahue
- Department of Radiology, Vanderbilt University, Nashville, TN, USA.
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50
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Almendros I, Farré R, Planas AM, Torres M, Bonsignore MR, Navajas D, Montserrat JM. Tissue oxygenation in brain, muscle, and fat in a rat model of sleep apnea: differential effect of obstructive apneas and intermittent hypoxia. Sleep 2011; 34:1127-33. [PMID: 21804675 DOI: 10.5665/sleep.1176] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
STUDY OBJECTIVES To test the hypotheses that the dynamic changes in brain oxygen partial pressure (PtO(2)) in response to obstructive apneas or to intermittent hypoxia differ from those in other organs and that the changes in brain PtO(2) in response to obstructive apneas is a source of oxidative stress. DESIGN Prospective controlled animal study. SETTING University laboratory. PARTICIPANTS 98 Sprague-Dawley rats. INTERVENTIONS Cerebral cortex, skeletal muscle, or visceral fat tissues were exposed in anesthetized animals subjected to either obstructive apneas or intermittent hypoxia (apneic and hypoxic events of 15 s each and 60 events/h) for 1 h. MEASUREMENTS AND RESULTS Arterial oxygen saturation (SpO(2)) presented a stable pattern, with similar desaturations during both stimuli. The PtO(2) was measured by a microelectrode. During obstructive apneas, a fast increase in cerebral PtO(2) was observed (38.2 ± 3.4 vs. 54.8 ± 5.9 mm Hg) but not in the rest of tissues. This particular cerebral response was not found during intermittent hypoxia. The cerebral content of reduced glutathione was decreased after obstructive apneas (46.2% ± 15.2%) compared to controls (100.0% ± 14.7%), but not after intermittent hypoxia. This antioxidant consumption after obstructive apneas was accompanied by increased cerebral lipid peroxidation under this condition. No changes were observed for these markers in the other tissues. CONCLUSIONS These results suggest that cerebral cortex could be protected in some way from hypoxic periods caused by obstructive apneas. The increased cerebral PtO(2) during obstructive apneas may, however, cause harmful effects (oxidative stress). The obstructive apnea model appears to be more adequate than the intermittent hypoxia model for studying brain changes associated with OSA.
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