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Qin N, Cao Q, Li F, Wang W, Peng X, Wang L. A nomogram based on quantitative EEG to predict the prognosis of nontraumatic coma patients in the neuro-intensive care unit. Intensive Crit Care Nurs 2024; 83:103618. [PMID: 38171953 DOI: 10.1016/j.iccn.2023.103618] [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: 08/07/2023] [Revised: 12/20/2023] [Accepted: 12/22/2023] [Indexed: 01/05/2024]
Abstract
OBJECTIVE We aimed to establish a quantitative electroencephalography-based prognostic prediction model specifically tailored for nontraumatic coma patients to guide clinical work. METHODS This retrospective study included 126 patients with nontraumatic coma admitted to the First Affiliated Hospital of Chongqing Medical University from December 2020 to December 2022. Six in-hospital deaths were excluded. The Glasgow Outcome Scale assessed the prognosis at 3 months after discharge. The least absolute shrinkage and selection operator regression analysis and stepwise regression method were applied to select the most relevant predictors. We developed a predictive model using binary logistic regression and then presented it as a nomogram. We assessed the predictive effectiveness and clinical utility of the model. RESULTS After excluding six deaths that occurred within the hospital, a total of 120 patients were included in this study. Three predictor variables were identified, including APACHE II score [39.129 (1.4244-1074.9000)], sleep cycle [OR: 0.006 (0.0002-0.1808)], and RAV [0.068 (0.0049-0.9500)]. The prognostic prediction model showed exceptional discriminative ability, with an AUC of 0.939 (95 % CI: 0.899-0.979). CONCLUSION A lack of sleep cycles, smaller relative alpha variants, and higher APACHE II scores were associated with a poor prognosis of nontraumatic coma patients in the neurointensive care unit at 3 months after discharge. CLINICAL IMPLICATION This study presents a novel methodology for the prognostic assessment of nontraumatic coma patients and is anticipated to play a significant role in clinical practice.
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Affiliation(s)
- Ningxiang Qin
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Qingqing Cao
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China; Department of Neurology, Bishan Hospital of Chongqing Medical University, Chongqing, China
| | - Feng Li
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Wei Wang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xi Peng
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.
| | - Liang Wang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
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Schoknecht K, Maechler M, Wallach I, Dreier JP, Liotta A, Berndt N. Isoflurane lowers the cerebral metabolic rate of oxygen and prevents hypoxia during cortical spreading depolarization in vitro: An integrative experimental and modeling study. J Cereb Blood Flow Metab 2024; 44:1000-1012. [PMID: 38140913 DOI: 10.1177/0271678x231222306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2023]
Abstract
Cortical spreading depolarization (SD) imposes a massive increase in energy demand and therefore evolves as a target for treatment following acute brain injuries. Anesthetics are empirically used to reduce energy metabolism in critical brain conditions, yet their effect on metabolism during SD remains largely unknown. We investigated oxidative metabolism during SD in brain slices from Wistar rats. Extracellular potassium ([K+]o), local field potential and partial tissue oxygen pressure (ptiO2) were measured simultaneously. The cerebral metabolic rate of oxygen (CMRO2) was calculated using a reaction-diffusion model. By that, we tested the effect of clinically relevant concentrations of isoflurane on CMRO2 during SD and modeled tissue oxygenation for different capillary pO2 values. During SD, CMRO2 increased 2.7-fold, resulting in transient hypoxia in the slice core. Isoflurane decreased CMRO2, reduced peak [K+]o, and prolonged [K+]o clearance, which indicates reduced synaptic transmission and sodium-potassium ATPase inhibition. Modeling tissue oxygenation during SD illustrates the need for increased capillary pO2 levels to prevent hypoxia. In the absence thereof, isoflurane could improve tissue oxygenation by lowering CMRO2. Therefore, isoflurane is a promising candidate for pre-clinical studies on neuronal survival in conditions involving SD.
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Affiliation(s)
- Karl Schoknecht
- Carl-Ludwig-Institute of Physiology, Medical Faculty, Leipzig University, Leipzig, Germany
| | - Mathilde Maechler
- Department of Anesthesiology and Intensive Care, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Institute of Neurophysiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Institute of Computer-Assisted Cardiovascular Medicine, Deutsches Herzzentrum der Charité (DHZC), Berlin, Germany
| | - Iwona Wallach
- Institute of Computer-Assisted Cardiovascular Medicine, Deutsches Herzzentrum der Charité (DHZC), Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Jens P Dreier
- Centre for Stroke Research Berlin, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Department of Experimental Neurology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Department of Neurology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Bernstein Centre for Computational Neuroscience Berlin, Berlin, Germany
- Einstein Centre for Neurosciences Berlin, Berlin, Germany
| | - Agustin Liotta
- Department of Anesthesiology and Intensive Care, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Institute of Neurophysiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Institute of Computer-Assisted Cardiovascular Medicine, Deutsches Herzzentrum der Charité (DHZC), Berlin, Germany
- Department of Experimental Neurology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Institute of Health at Charité - Universitätsmedizin Berlin, Berlin
- Neuroscience Research Center, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Nikolaus Berndt
- Institute of Computer-Assisted Cardiovascular Medicine, Deutsches Herzzentrum der Charité (DHZC), Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), Department of Molecular Toxicology, Nuthetal, Germany
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Chan DYC, Li LF, Lui WM, Poon CCM, Tsang ACO, Leung GKK. Predictive value of Bispectral Index (BIS) in emergency neurosurgical patients: Loss of BIS reactivity to propofol predicts poor functional outcomes. Clin Neurol Neurosurg 2022; 221:107382. [DOI: 10.1016/j.clineuro.2022.107382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 11/26/2022]
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Vestergaard MB, Frederiksen JL, Larsson HBW, Cramer SP. Cerebrovascular Reactivity and Neurovascular Coupling in Multiple Sclerosis-A Systematic Review. Front Neurol 2022; 13:912828. [PMID: 35720104 PMCID: PMC9198441 DOI: 10.3389/fneur.2022.912828] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 05/04/2022] [Indexed: 11/25/2022] Open
Abstract
The inflammatory processes observed in the central nervous system in multiple sclerosis (MS) could damage the endothelium of the cerebral vessels and lead to a dysfunctional regulation of vessel tonus and recruitment, potentially impairing cerebrovascular reactivity (CVR) and neurovascular coupling (NVC). Impaired CVR or NVC correlates with declining brain health and potentially plays a causal role in the development of neurodegenerative disease. Therefore, we examined studies on CVR or NVC in MS patients to evaluate the evidence for impaired cerebrovascular function as a contributing disease mechanism in MS. Twenty-three studies were included (12 examined CVR and 11 examined NVC). Six studies found no difference in CVR response between MS patients and healthy controls. Five studies observed reduced CVR in patients. This discrepancy can be because CVR is mainly affected after a long disease duration and therefore is not observed in all patients. All studies used CO2 as a vasodilating stimulus. The studies on NVC demonstrated diverse results; hence a conclusion that describes all the published observations is difficult to find. Future studies using quantitative techniques and larger study samples are needed to elucidate the discrepancies in the reported results.
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Affiliation(s)
- Mark B Vestergaard
- Functional Imaging Unit, Department of Clinical Physiology and Nuclear Medicine, Copenhagen University Hospital Rigshospitalet, Glostrup, Denmark
| | - Jette L Frederiksen
- Danish Multiple Sclerosis Center, Department of Neurology, Copenhagen University Hospital Rigshospitalet, Glostrup, Denmark.,Department of Clinical Medicine, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark
| | - Henrik B W Larsson
- Functional Imaging Unit, Department of Clinical Physiology and Nuclear Medicine, Copenhagen University Hospital Rigshospitalet, Glostrup, Denmark.,Danish Multiple Sclerosis Center, Department of Neurology, Copenhagen University Hospital Rigshospitalet, Glostrup, Denmark
| | - Stig P Cramer
- Functional Imaging Unit, Department of Clinical Physiology and Nuclear Medicine, Copenhagen University Hospital Rigshospitalet, Glostrup, Denmark
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Sevoflurane Effects on Neuronal Energy Metabolism Correlate with Activity States While Mitochondrial Function Remains Intact. Int J Mol Sci 2022; 23:ijms23063037. [PMID: 35328453 PMCID: PMC8949020 DOI: 10.3390/ijms23063037] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/04/2022] [Accepted: 03/09/2022] [Indexed: 12/04/2022] Open
Abstract
During general anesthesia, alterations in neuronal metabolism may induce neurotoxicity and/or neuroprotection depending on the dose and type of the applied anesthetic. In this study, we investigate the effects of clinically relevant concentrations of sevoflurane (2% and 4%, i.e., 1 and 2 MAC) on different activity states in hippocampal slices of young Wistar rats. We combine electrophysiological recordings, partial tissue oxygen (ptiO2) measurements, and flavin adenine dinucleotide (FAD) imaging with computational modeling. Sevoflurane minimally decreased the cerebral metabolic rate of oxygen (CMRO2) while decreasing synaptic transmission in naive slices. During pharmacologically induced gamma oscillations, sevoflurane impaired network activity, thereby decreasing CMRO2. During stimulus-induced neuronal activation, sevoflurane decreased CMRO2 and excitability while basal metabolism remained constant. In this line, stimulus-induced FAD transients decreased without changes in basal mitochondrial redox state. Integration of experimental data and computer modeling revealed no evidence for a direct effect of sevoflurane on key enzymes of the citric acid cycle or oxidative phosphorylation. Clinically relevant concentrations of sevoflurane generated a decent decrease in energy metabolism, which was proportional to the present neuronal activity. Mitochondrial function remained intact under sevoflurane, suggesting a better metabolic profile than isoflurane or propofol.
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Joo P, Lee H, Wang S, Kim S, Hudetz AG. Network Model With Reduced Metabolic Rate Predicts Spatial Synchrony of Neuronal Activity. Front Comput Neurosci 2021; 15:738362. [PMID: 34690730 PMCID: PMC8529180 DOI: 10.3389/fncom.2021.738362] [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: 07/08/2021] [Accepted: 09/01/2021] [Indexed: 11/25/2022] Open
Abstract
In a cerebral hypometabolic state, cortical neurons exhibit slow synchronous oscillatory activity with sparse firing. How such a synchronization spatially organizes as the cerebral metabolic rate decreases have not been systemically investigated. We developed a network model of leaky integrate-and-fire neurons with an additional dependency on ATP dynamics. Neurons were scattered in a 2D space, and their population activity patterns at varying ATP levels were simulated. The model predicted a decrease in firing activity as the ATP production rate was lowered. Under hypometabolic conditions, an oscillatory firing pattern, that is, an ON-OFF cycle arose through a failure of sustainable firing due to reduced excitatory positive feedback and rebound firing after the slow recovery of ATP concentration. The firing rate oscillation of distant neurons developed at first asynchronously that changed into burst suppression and global synchronization as ATP production further decreased. These changes resembled the experimental data obtained from anesthetized rats, as an example of a metabolically suppressed brain. Together, this study substantiates a novel biophysical mechanism of neuronal network synchronization under limited energy supply conditions.
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Affiliation(s)
- Pangyu Joo
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States.,Department of Physics, Pohang University of Science and Technology, Pohang, South Korea
| | - Heonsoo Lee
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
| | - Shiyong Wang
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
| | - Seunghwan Kim
- Department of Physics, Pohang University of Science and Technology, Pohang, South Korea
| | - Anthony G Hudetz
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
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Hadjipavlou G, Warnaby CE, Fitzgerald J, Sleigh J. Contributions of synaptic and astrocyte physiology to the anaesthetised encephalogram revealed using a computational model. Br J Anaesth 2021; 126:985-995. [PMID: 33773753 DOI: 10.1016/j.bja.2021.01.034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 01/21/2021] [Accepted: 01/22/2021] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND General anaesthesia is known to enhance inhibitory synaptic transmission to produce characteristic effects on the EEG and reduction in brain metabolism secondary to reduced neuronal activity. Evidence suggests that anaesthesia might have a direct effect on synaptic metabolic processes, and this relates to anaesthesia sensitivity. We explored elements of synaptic transmission looking for possible contributions to the anaesthetised EEG and how it may modulate anaesthesia sensitivity. METHODS We developed a Hodgkin-Huxley-type neural network computer simulation capable of mimicking anaesthetic prolongation of gamma-aminobutyric acid (GABA)ergic inhibitory postsynaptic potentials (IPSPs), and capable of altering postsynaptic ion homeostasis and neurotransmitter recycling. We examined their interactions on simulated electrocorticography (sECoG), and compared these with published anaesthesia EEG spectra. RESULTS The sECoG spectra from the model were comparable with published normal awake EEG spectra. Prolongation of IPSP duration in the model caused inhibition of high frequencies and saturation of low frequencies with a peak in keeping with current evidence. IPSP prolongation alone was unable to reproduce alpha rhythms or the generalised increase in EEG power found with anaesthesia. Adding inhibition of postsynaptic ion homeostasis to IPSP prolongation helped retain alpha rhythms, increased sECoG power, and antagonised the slow-wave saturation peak in a dose-dependent fashion that appeared dependent on the postsynaptic membrane potential, providing a plausible mechanism for how metabolic changes can modulate anaesthesia sensitivity. CONCLUSIONS Our model suggests how metabolic processes can modulate anaesthesia and produce non-receptor dependent drug sensitivity.
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Affiliation(s)
- George Hadjipavlou
- Nuffield Department of Anaesthesia, Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Headington, Oxford, UK.
| | - Catherine E Warnaby
- Wellcome Centre for Integrative Neuroimaging, Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - James Fitzgerald
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Jamie Sleigh
- Department of Anaesthesia, Waikato Clinical Campus, University of Auckland, Hamilton, New Zealand
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Feasibility of combining functional near-infrared spectroscopy with electroencephalography to identify chronic stroke responders to cerebellar transcranial direct current stimulation-a computational modeling and portable neuroimaging methodological study. THE CEREBELLUM 2021; 20:853-871. [PMID: 33675516 DOI: 10.1007/s12311-021-01249-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/21/2021] [Indexed: 10/22/2022]
Abstract
Feasibility of portable neuroimaging of cerebellar transcranial direct current stimulation (ctDCS) effects on the cerebral cortex has not been investigated vis-à-vis cerebellar lobular electric field strength. We studied functional near-infrared spectroscopy (fNIRS) in conjunction with electroencephalography (EEG) to measure changes in the brain activation at the prefrontal cortex (PFC) and the sensorimotor cortex (SMC) following ctDCS as well as virtual reality-based balance training (VBaT) before and after ctDCS treatment in 12 hemiparetic chronic stroke survivors. We performed general linear modeling (GLM) that putatively associated the lobular electric field strength with the changes in the fNIRS-EEG measures at the ipsilesional and contra-lesional PFC and SMC. Here, fNIRS-EEG measures were found in the latent space from canonical correlation analysis (CCA) between the changes in total hemoglobin (tHb) concentrations (0.01-0.07Hz and 0.07-0.13Hz bands) and log10-transformed EEG bandpower within 1-45 Hz where significant (Wilks' lambda>0.95) canonical correlations were found only for the 0.07-0.13-Hz band. Also, the first principal component (97.5% variance accounted for) of the mean lobular electric field strength was a good predictor of the latent variables of oxy-hemoglobin (O2Hb) concentrations and log10-transformed EEG bandpower. GLM also provided insights into non-responders to ctDCS who also performed poorly in the VBaT due to ideomotor apraxia. Future studies should investigate fNIRS-EEG joint-imaging in a larger cohort to identify non-responders based on GLM fitting to the fNIRS-EEG data.
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The influence of induction speed on the frontal (processed) EEG. Sci Rep 2020; 10:19444. [PMID: 33173114 PMCID: PMC7655958 DOI: 10.1038/s41598-020-76323-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 10/27/2020] [Indexed: 12/12/2022] Open
Abstract
The intravenous injection of the anaesthetic propofol is clinical routine to induce loss of responsiveness (LOR). However, there are only a few studies investigating the influence of the injection rate on the frontal electroencephalogram (EEG) during LOR. Therefore, we focused on changes of the frontal EEG especially during this period. We included 18 patients which were randomly assigned to a slow or fast induction group and recorded the frontal EEG. Based on this data, we calculated the power spectral density, the band powers and band ratios. To analyse the behaviour of processed EEG parameters we calculated the beta ratio, the spectral entropy, and the spectral edge frequency. Due to the prolonged induction period in the slow injection group we were able to distinguish loss of responsiveness to verbal command (LOvR) from loss of responsiveness to painful stimulus (LOpR) whereas in the fast induction group we could not. At LOpR, we observed a higher relative alpha and beta power in the slow induction group while the relative power in the delta range was lower than in the fast induction group. When concentrating on the slow induction group the increase in relative alpha power pre-LOpR and even before LOvR indicated that frontal EEG patterns, which have been suggested as an indicator of unconsciousness, can develop before LOR. Further, LOvR was best reflected by an increase of the alpha to delta ratio, and LOpR was indicated by a decrease of the beta to alpha ratio. These findings highlight the different spectral properties of the EEG at various levels of responsiveness and underline the influence of the propofol injection rate on the frontal EEG during induction of general anesthesia.
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Kaya C, Cebeci H, Tomak L, Ozbalci GS. Prospective Randomized Trial Between Propofol Intravenous and Sevoflurane Inhaled Anesthesia on Cerebral Oximetry. Bariatr Surg Pract Patient Care 2020. [DOI: 10.1089/bari.2019.0038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Cengiz Kaya
- Department of Anesthesiology, School of Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Halil Cebeci
- Department of Anesthesiology, School of Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Leman Tomak
- Department of Biostatistics and Public Health, School of Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Gokhan Selcuk Ozbalci
- Department of General Surgery, School of Medicine, Ondokuz Mayis University, Samsun, Turkey
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Veraar CM, Rinösl H, Kühn K, Skhirtladze-Dworschak K, Felli A, Mouhieddine M, Menger J, Pataraia E, Ankersmit HJ, Dworschak M. Non-pulsatile blood flow is associated with enhanced cerebrovascular carbon dioxide reactivity and an attenuated relationship between cerebral blood flow and regional brain oxygenation. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2019; 23:426. [PMID: 31888721 PMCID: PMC6937980 DOI: 10.1186/s13054-019-2671-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 11/13/2019] [Indexed: 12/16/2022]
Abstract
BACKGROUND Systemic blood flow in patients on extracorporeal assist devices is frequently not or only minimally pulsatile. Loss of pulsatile brain perfusion, however, has been implicated in neurological complications. Furthermore, the adverse effects of absent pulsatility on the cerebral microcirculation are modulated similarly as CO2 vasoreactivity in resistance vessels. During support with an extracorporeal assist device swings in arterial carbon dioxide partial pressures (PaCO2) that determine cerebral oxygen delivery are not uncommon-especially when CO2 is eliminated by the respirator as well as via the gas exchanger of an extracorporeal membrane oxygenation machine. We, therefore, investigated whether non-pulsatile flow affects cerebrovascular CO2 reactivity (CVR) and regional brain oxygenation (rSO2). METHODS In this prospective, single-centre case-control trial, we studied 32 patients undergoing elective cardiac surgery. Blood flow velocity in the middle cerebral artery (MCAv) as well as rSO2 was determined during step changes of PaCO2 between 30, 40, and 50 mmHg. Measurements were conducted on cardiopulmonary bypass during non-pulsatile and postoperatively under pulsatile blood flow at comparable test conditions. Corresponding changes of CVR and concomitant rSO2 alterations were determined for each flow mode. Each patient served as her own control. RESULTS MCAv was generally lower during hypocapnia than during normocapnia and hypercapnia (p < 0.0001). However, the MCAv/PaCO2 slope during non-pulsatile flow was 14.4 cm/s/mmHg [CI 11.8-16.9] and 10.4 cm/s/mmHg [CI 7.9-13.0] after return of pulsatility (p = 0.03). During hypocapnia, non-pulsatile CVR (4.3 ± 1.7%/mmHg) was higher than pulsatile CVR (3.1 ± 1.3%/mmHg, p = 0.01). Independent of the flow mode, we observed a decline in rSO2 during hypocapnia and a corresponding rise during hypercapnia (p < 0.0001). However, the relationship between ΔrSO2 and ΔMCAv was less pronounced during non-pulsatile flow. CONCLUSIONS Non-pulsatile perfusion is associated with enhanced cerebrovascular CVR resulting in greater relative decreases of cerebral blood flow during hypocapnia. Heterogenic microvascular perfusion may account for the attenuated ΔrSO2/ΔMCAv slope. Potential hazards related to this altered regulation of cerebral perfusion still need to be assessed. TRIAL REGISTRATION The study was retrospectively registered on October 30, 2018, with Clinical Trial.gov (NCT03732651).
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Affiliation(s)
- Cecilia Maria Veraar
- Division of Cardiothoracic and Vascular Anaesthesia and Intensive Care Medicine, Department of Anaesthesia, Intensive Care Medicine, and Pain Medicine, Vienna General Hospital, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Harald Rinösl
- Department of Anaesthesia and Intensive Care Medicine, LKH Feldkirch, Feldkirch, Austria
| | - Karina Kühn
- Department of Anaesthesia, Intensive Care Medicine and Pain Medicine, Klinikum Traunstein, Traunstein, Germany
| | - Keso Skhirtladze-Dworschak
- Division of Cardiothoracic and Vascular Anaesthesia and Intensive Care Medicine, Department of Anaesthesia, Intensive Care Medicine, and Pain Medicine, Vienna General Hospital, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Alessia Felli
- Division of Cardiothoracic and Vascular Anaesthesia and Intensive Care Medicine, Department of Anaesthesia, Intensive Care Medicine, and Pain Medicine, Vienna General Hospital, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Mohamed Mouhieddine
- Division of Cardiothoracic and Vascular Anaesthesia and Intensive Care Medicine, Department of Anaesthesia, Intensive Care Medicine, and Pain Medicine, Vienna General Hospital, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Johannes Menger
- Division of Cardiothoracic and Vascular Anaesthesia and Intensive Care Medicine, Department of Anaesthesia, Intensive Care Medicine, and Pain Medicine, Vienna General Hospital, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Ekaterina Pataraia
- Department of Neurology, Vienna General Hospital, Medical University of Vienna, Vienna, Austria
| | - Hendrik Jan Ankersmit
- Division of Thoracic Surgery, Department of Surgery, Vienna General Hospital, Medical University of Vienna, Vienna, Austria
| | - Martin Dworschak
- Division of Cardiothoracic and Vascular Anaesthesia and Intensive Care Medicine, Department of Anaesthesia, Intensive Care Medicine, and Pain Medicine, Vienna General Hospital, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
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12
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Schneider J, Berndt N, Papageorgiou IE, Maurer J, Bulik S, Both M, Draguhn A, Holzhütter HG, Kann O. Local oxygen homeostasis during various neuronal network activity states in the mouse hippocampus. J Cereb Blood Flow Metab 2019; 39:859-873. [PMID: 29099662 PMCID: PMC6501513 DOI: 10.1177/0271678x17740091] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cortical information processing comprises various activity states emerging from timed synaptic excitation and inhibition. However, the underlying energy metabolism is widely unknown. We determined the cerebral metabolic rate of oxygen (CMRO2) along a tissue depth of <0.3 mm in the hippocampal CA3 region during various network activities, including gamma oscillations and sharp wave-ripples that occur during wakefulness and sleep. These physiological states associate with sensory perception and memory formation, and critically depend on perisomatic GABA inhibition. Moreover, we modelled vascular oxygen delivery based on quantitative microvasculature analysis. (1) Local CMRO2 was highest during gamma oscillations (3.4 mM/min), medium during sharp wave-ripples, asynchronous activity and isoflurane application (2.0-1.6 mM/min), and lowest during tetrodotoxin application (1.4 mM/min). (2) Energy expenditure of axonal and synaptic signaling accounted for >50% during gamma oscillations. (3) CMRO2 positively correlated with number and synchronisation of activated synapses, and neural multi-unit activity. (4) The median capillary distance was 44 µm. (5) The vascular oxygen partial pressure of 33 mmHg was needed to sustain oxidative phosphorylation during gamma oscillations. We conclude that gamma oscillations featuring high energetics require a hemodynamic response to match oxygen consumption of respiring mitochondria, and that perisomatic inhibition significantly contributes to the brain energy budget.
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Affiliation(s)
- Justus Schneider
- 1 Institute of Physiology and Pathophysiology, and Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany
| | - Nikolaus Berndt
- 2 Computational Systems Biochemistry, Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Ismini E Papageorgiou
- 1 Institute of Physiology and Pathophysiology, and Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany
| | - Jana Maurer
- 1 Institute of Physiology and Pathophysiology, and Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany
| | - Sascha Bulik
- 2 Computational Systems Biochemistry, Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Martin Both
- 1 Institute of Physiology and Pathophysiology, and Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany
| | - Andreas Draguhn
- 1 Institute of Physiology and Pathophysiology, and Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany
| | - Hermann-Georg Holzhütter
- 2 Computational Systems Biochemistry, Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Oliver Kann
- 1 Institute of Physiology and Pathophysiology, and Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany
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13
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Chalela R, Gallart L, Pascual-Guardia S, Sancho-Muñoz A, Gea J, Orozco-Levi M. Bispectral index in hypercapnic encephalopathy associated with COPD exacerbation: a pilot study. Int J Chron Obstruct Pulmon Dis 2019; 13:2961. [PMID: 30310272 PMCID: PMC6167126 DOI: 10.2147/copd.s167020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Hypercapnic encephalopathy is relatively frequent in severe exacerbations of COPD (ECOPDs), with its intensity usually being evaluated through clinical scales. Bispectral index (BIS) is a relatively new technique, based on the analysis of the electroencephalographic signal, which provides a good approximation to the level of consciousness, having already been validated in anesthesia. OBJECTIVE The objective of the study was to evaluate the utility of BIS in the assessment of the intensity of hypercapnic encephalopathy in ECOPD patients. PATIENTS AND METHODS A total of ten ECOPD patients were included, and the level of brain activity was assessed using BIS and different scales: Glasgow Coma Scale, Ramsay Sedation Scale (RSS), and Richmond Agitation-Sedation Scale. The evaluation was performed both in the acute phase and 3 months after discharge. RESULTS BIS was recorded for a total of about 600 minutes. During ECOPD, BIS values ranged from 58.8 (95% CI: 48.6-69) for RSS score of 4 to 92.2 (95% CI: 90.1-94.3) for RSS score of 2. A significant correlation was observed between values obtained with BIS and those from the three scales, although the best fit was for RSS, followed by Glasgow and Richmond (r=-0.757, r=0.701, and r=0.615, respectively; P<0.001 for all). In the stable phase after discharge, BIS showed values considered as normal for a wake state (94.6; 95% CI: 91.7-97.9). CONCLUSION BIS may be useful for the objective early detection and automatic monitoring of the intensity of hypercapnic encephalopathy in ECOPD, facilitating the early detection and follow-up of this condition, which may avoid management problems in these patients.
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Affiliation(s)
- Roberto Chalela
- Respiratory Medicine Department, Hospital del Mar-IMIM, Barcelona, Spain, .,Department CEXS, Universitat Pompeu Fabra, Barcelona, Spain, .,CIBERES, ISCIII, Barcelona, Spain,
| | - Lluis Gallart
- Department of Anesthesia, Hospital del Mar-IMIM, Barcelona, Spain.,Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Sergi Pascual-Guardia
- Respiratory Medicine Department, Hospital del Mar-IMIM, Barcelona, Spain, .,Department CEXS, Universitat Pompeu Fabra, Barcelona, Spain, .,CIBERES, ISCIII, Barcelona, Spain,
| | - Antonio Sancho-Muñoz
- Respiratory Medicine Department, Hospital del Mar-IMIM, Barcelona, Spain, .,Department CEXS, Universitat Pompeu Fabra, Barcelona, Spain,
| | - Joaquim Gea
- Respiratory Medicine Department, Hospital del Mar-IMIM, Barcelona, Spain, .,Department CEXS, Universitat Pompeu Fabra, Barcelona, Spain, .,CIBERES, ISCIII, Barcelona, Spain,
| | - Mauricio Orozco-Levi
- Respiratory Medicine Department, Hospital del Mar-IMIM, Barcelona, Spain, .,Department CEXS, Universitat Pompeu Fabra, Barcelona, Spain, .,CIBERES, ISCIII, Barcelona, Spain,
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14
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Villacorta J, Kerbaul F, Collart F, Guidon C, Bonnet M, Guillen JC, Gouin F. Perioperative Cerebral Ischaemia in Cardiac Surgery and BIS. Anaesth Intensive Care 2019; 33:514-7. [PMID: 16119495 DOI: 10.1177/0310057x0503300415] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A 46-year-old woman was monitored by bispectral index monitoring (BIS) during redo aortic and mitral valve replacement. On release of the aortic cross clamp there was a sudden, severe, unexplained, and sustained fall in the BIS value. Postoperatively, a CT scan was consistent with multiple ischaemic lesions. The lesions were presumed to be due to air embolism. This case suggests that a sudden unexplained and persistent fall in BIS may indicate cerebral ischaemia.
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Affiliation(s)
- J Villacorta
- Department of Anesthesiology and Intensive Care, Groupe Hospitalier Timone, Marseilles, France
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15
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Puri GD, Bagchi A, Anandamurthy B, Dhaliwal RS. The Bispectral Index and Induced Hypothermia— Electrocerebral Silence at an Unusually High Temperature. Anaesth Intensive Care 2019; 31:578-80. [PMID: 14601285 DOI: 10.1177/0310057x0303100515] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The optimal temperature for deep hypothermic circulatory arrest remains undefined. We present a case in which Bispectral Index monitoring during hypothermic cardiopulmonary bypass showed electrocerebral silence at a higher temperature than previously reported. Bispectral Index monitoring may be a potentially useful tool in surgery employing deep hypothermic circulatory arrest.
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Affiliation(s)
- G D Puri
- Department of Anaesthesia and Intensive Care, Post Graduate Institute of Medical Education and Research, Chandigarh-160012, India
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16
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Laaksonen L, Kallioinen M, Långsjö J, Laitio T, Scheinin A, Scheinin J, Kaisti K, Maksimow A, Kallionpää RE, Rajala V, Johansson J, Kantonen O, Nyman M, Sirén S, Valli K, Revonsuo A, Solin O, Vahlberg T, Alkire M, Scheinin H. Comparative effects of dexmedetomidine, propofol, sevoflurane, and S-ketamine on regional cerebral glucose metabolism in humans: a positron emission tomography study. Br J Anaesth 2018; 121:281-290. [PMID: 29935583 DOI: 10.1016/j.bja.2018.04.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/16/2017] [Indexed: 11/28/2022] Open
Abstract
INTRODUCTION The highly selective α2-agonist dexmedetomidine has become a popular sedative for neurointensive care patients. However, earlier studies have raised concern that dexmedetomidine might reduce cerebral blood flow without a concomitant decrease in metabolism. Here, we compared the effects of dexmedetomidine on the regional cerebral metabolic rate of glucose (CMRglu) with three commonly used anaesthetic drugs at equi-sedative doses. METHODS One hundred and sixty healthy male subjects were randomised to EC50 for verbal command of dexmedetomidine (1.5 ng ml-1; n=40), propofol (1.7 μg ml-1; n=40), sevoflurane (0.9% end-tidal; n=40) or S-ketamine (0.75 μg ml-1; n=20) or placebo (n=20). Anaesthetics were administered using target-controlled infusion or vapouriser with end-tidal monitoring. 18F-labelled fluorodeoxyglucose was administered 20 min after commencement of anaesthetic administration, and high-resolution positron emission tomography with arterial blood activity samples was used to quantify absolute CMRglu for whole brain and 15 brain regions. RESULTS At the time of [F18]fluorodeoxyglucose injection, 55% of dexmedetomidine, 45% of propofol, 85% of sevoflurane, 45% of S-ketamine, and 0% of placebo subjects were unresponsive. Whole brain CMRglu was 63%, 71%, 71%, and 96% of placebo in the dexmedetomidine, propofol, sevoflurane, and S-ketamine groups, respectively (P<0.001 between the groups). The lowest CMRglu was observed in nearly all brain regions with dexmedetomidine (P<0.05 compared with all other groups). With S-ketamine, CMRglu did not differ from placebo. CONCLUSIONS At equi-sedative doses in humans, potency in reducing CMRglu was dexmedetomidine>propofol>ketamine=placebo. These findings alleviate concerns for dexmedetomidine-induced vasoconstriction and cerebral ischaemia. CLINICAL TRIAL REGISTRATION NCT02624401.
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Affiliation(s)
- L Laaksonen
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland; Department of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland.
| | - M Kallioinen
- Department of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland
| | - J Långsjö
- Department of Intensive Care, Tampere University Hospital, Tampere, Finland
| | - T Laitio
- Department of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland
| | - A Scheinin
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland; Department of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland
| | - J Scheinin
- Department of Anaesthesiology, Kuopio University Hospital, Kuopio, Finland
| | - K Kaisti
- Department of Anaesthesiology and Intensive Care, Oulu University Hospital, Oulu, Finland
| | - A Maksimow
- Department of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland
| | - R E Kallionpää
- Department of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland; Department of Psychology and Speech-Language Pathology, Turku Brain and Mind Center, University of Turku, Turku, Finland
| | - V Rajala
- Department of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland
| | - J Johansson
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland; Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - O Kantonen
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland; Department of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland; University of California, Irvine, CA, USA
| | - M Nyman
- Department of Radiology, Turku University Hospital, Turku, Finland
| | - S Sirén
- Institute of Biomedicine, University of Turku, Unit of Clinical Pharmacology, Turku University Hospital, Turku, Finland
| | - K Valli
- Department of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland; Department of Psychology and Speech-Language Pathology, Turku Brain and Mind Center, University of Turku, Turku, Finland; Department of Cognitive Neuroscience and Philosophy, School of Bioscience, University of Skövde, Sweden
| | - A Revonsuo
- Department of Psychology and Speech-Language Pathology, Turku Brain and Mind Center, University of Turku, Turku, Finland; Department of Cognitive Neuroscience and Philosophy, School of Bioscience, University of Skövde, Sweden
| | - O Solin
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland
| | - T Vahlberg
- Department of Clinical Medicine, Biostatistics, University of Turku and Turku University Hospital, Turku, Finland
| | - M Alkire
- University of California, Irvine, CA, USA
| | - H Scheinin
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland; Department of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland; Integrative Physiology and Pharmacology, Institute of Biomedicine, University of Turku, Turku, Finland
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17
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Scheib CM. Brainstem Influence on Thalamocortical Oscillations during Anesthesia Emergence. Front Syst Neurosci 2017; 11:66. [PMID: 28959192 PMCID: PMC5603712 DOI: 10.3389/fnsys.2017.00066] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 08/31/2017] [Indexed: 12/23/2022] Open
Abstract
Theories of mechanisms that impair or prevent consciousness during anesthesia that are related to thalamocortical oscillations have been proposed. Many methods of EEG analysis have been proposed as measures of anesthetic effects but only a few have potential to provide measures of those anesthetic effects that are directly related to thalamocortical oscillations. Some of these methods will be explained and demonstrated with examples chosen to provide evidence for or against two of the proposed mechanisms. The first of the two mechanisms to be addressed is the “traveling peak” (Ching et al., 2010), which relates to anesthetic agents synchronizing neural oscillations that occur in subjects who are awake and reducing their frequency from the gamma (25–40 Hz) to the beta range (13–24 Hz) as a state of sedation develops. The mechanism continues to lower the frequency of this oscillation to the alpha (8–12 Hz) range. In the alpha frequency range, responses to sounds and words stop. It has been proposed that the mechanism changes fundamentally at this point and the oscillations are not compatible with consciousness. The second mechanism that will be addressed is a modification of the generally accepted mechanism for the spindle oscillations that occur during natural sleep (Steriade et al., 1993a,b). These two different mechanisms imply two different patterns for changes in the frequency of the thalamocortical oscillations during emergence. The first mechanism implies that the frequency of the oscillations should increase from the alpha range to the beta range during emergence. The “spindle” mechanism implies that the frequency of the oscillation would not increase much beyond the alpha range. Examples of EEG recordings during anesthesia and emergence from anesthesia were found which were consistent with either mechanism alone or both mechanisms at the same time. Neither theory was able to explain all examples. It is possible that both mechanisms can occur and that brainstem activity may influence the characteristics of emergence. The brainstem activity in question may be influenced by nociception and analgesic supplementation. It may be possible to control the path of emergence by controlling brainstem activity with opioids and other agents in order to allow the patient to awaken without going through an excitement phase or delirium at the transition to consciousness.
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Affiliation(s)
- Christopher M Scheib
- Anesthesia Department, W. G. (Bill) Hefner VA Medical CenterSalisbury, NC, United States
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18
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Hajat Z, Ahmad N, Andrzejowski J. The role and limitations of EEG-based depth of anaesthesia monitoring in theatres and intensive care. Anaesthesia 2017; 72 Suppl 1:38-47. [DOI: 10.1111/anae.13739] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2016] [Indexed: 12/14/2022]
Affiliation(s)
- Z. Hajat
- Sheffield Teaching Hospitals NHS Trust; Sheffield UK
| | - N. Ahmad
- Sheffield Teaching Hospitals NHS Trust; Sheffield UK
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19
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Positron Emission Tomography: Basic Principles, New Applications, and Studies Under Anesthesia. Int Anesthesiol Clin 2016; 54:109-28. [PMID: 26655512 DOI: 10.1097/aia.0000000000000090] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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20
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A comparative analysis of the effects of sevoflurane and propofol on cerebral oxygenation during steep Trendelenburg position and pneumoperitoneum for robotic-assisted laparoscopic prostatectomy. J Anesth 2016; 30:949-955. [PMID: 27565964 PMCID: PMC5097119 DOI: 10.1007/s00540-016-2241-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 08/13/2016] [Indexed: 11/17/2022]
Abstract
Purpose Steep Trendelenburg position and pneumoperitoneum during robotic-assisted laparoscopic prostatectomy (RALP) increase intracranial pressure (ICP) and may alter cerebral blood flow (CBF) and oxygenation. Volatile anesthetics and propofol have different effects on ICP, CBF, and cerebral metabolic rate and may have different impact on cerebral oxygenation during RALP. In this study, we measured jugular venous bulb oxygenation (SjO2) and regional oxygen saturation (SctO2) in patients undergoing RALP to evaluate cerebral oxygenation and compared the effects of sevoflurane and propofol. We also verified whether SctO2 may be an alternative to SjO2. Methods Fifty patients scheduled for RALP were randomly assigned to undergo sevoflurane (group S) or propofol (group P) anesthesia. SjO2, SctO2, mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), central venous pressure (CVP), partial pressures of arterial oxygen (PaO2) and carbon dioxide (PaCO2), hemoglobin concentration (Hb), Bispectral Index (BIS) and nasopharyngeal temperature (BT) were recorded 5 min before surgery commencement, 5 min after pneumoperitoneum, 5, 30, 60, 90, and 120 min after pneumoperitoneum in a Trendelenburg position, and after desufflation in a supine position. Results SjO2 was significantly higher in group S than in group P at all measurement points [group S vs. group P: 77 % (11) vs. 65 % (13), mean of all measurement points (1SD); p < 0.01]. Linear regression analysis (β = 0.106; r2 = 0.065; p = 0.004) shows a weak relationship between SjO2 and SctO2. Conclusions Sevoflurane maintains higher SjO2 levels than propofol during RALP. SctO2 does not accurately reflect SjO2.
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21
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Kabukcu HK, Sahin N, Ozkaloglu K, Golbasi I, Titiz TA. Bispectral Index Monitoring in Patients Undergoing Open Heart Surgery. Braz J Cardiovasc Surg 2016; 31:178-82. [PMID: 27556320 PMCID: PMC5062717 DOI: 10.5935/1678-9741.20160038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 05/03/2016] [Indexed: 11/20/2022] Open
Abstract
Introduction To obtain the optimal anesthesia depth is not easy in cardiovascular surgery
patients where the haemodynamic reserve is limited, due to reasons such as
not being able to give the desired dose of anesthetic agent, or the change
in the pharmacokinetics of the agent in the heart-lung machine. This study
was planned to assess the contribution of bispectral index (BIS) monitoring
in the depth of anesthesia. Methods The patients were divided into 2 groups, and BIS monitoring was used for each
patient. Group 1 (G1 n=35): keeping the BIS monitor screen open, the
anesthesia need was set. Group 2 (G2 n=35): BIS monitor was tied to the
patient and the monitor screen was closed in such a way that the
anaesthesist couldn't see the BIS value. When the recording time came, the
data on the monitor was recorded. The need for the anesthetic agent was set
according to the parameters such as haemodynamics or follow up of pupils,
instead of BIS value, by titrating the anesthetic infusion doses. Results BIS values were similar in both groups before the induction, BIS values in
both groups showed a decrease, showing no significant statistical difference
(P>0.05). One patient in each group said that he
dreamt, and one patient in G2 said that he had heard a noise and felt that
he was taken from one place to another. Conclusion The management should be done with clinical evaluation, haemodynamics and
other monitorization methods and BIS monitoring findings together.
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Affiliation(s)
| | - Nursel Sahin
- Medical Faculty, Akdeniz University, Antalya, Turkey
| | | | - Ilhan Golbasi
- Medical Faculty, Akdeniz University, Antalya, Turkey
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Stender J, Mortensen KN, Thibaut A, Darkner S, Laureys S, Gjedde A, Kupers R. The Minimal Energetic Requirement of Sustained Awareness after Brain Injury. Curr Biol 2016; 26:1494-9. [PMID: 27238279 DOI: 10.1016/j.cub.2016.04.024] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 03/20/2016] [Accepted: 04/08/2016] [Indexed: 11/18/2022]
Abstract
Differentiation of the minimally conscious state (MCS) and the unresponsive wakefulness syndrome (UWS) is a persistent clinical challenge [1]. Based on positron emission tomography (PET) studies with [(18)F]-fluorodeoxyglucose (FDG) during sleep and anesthesia, the global cerebral metabolic rate of glucose has been proposed as an indicator of consciousness [2, 3]. Likewise, FDG-PET may contribute to the clinical diagnosis of disorders of consciousness (DOCs) [4, 5]. However, current methods are non-quantitative and have important drawbacks deriving from visually guided assessment of relative changes in brain metabolism [4]. We here used FDG-PET to measure resting state brain glucose metabolism in 131 DOC patients to identify objective quantitative metabolic indicators and predictors of awareness. Quantitation of images was performed by normalizing to extracerebral tissue. We show that 42% of normal cortical activity represents the minimal energetic requirement for the presence of conscious awareness. Overall, the cerebral metabolic rate accounted for the current level, or imminent return, of awareness in 94% of the patient population, suggesting a global energetic threshold effect, associated with the reemergence of consciousness after brain injury. Our data further revealed that regional variations relative to the global resting metabolic level reflect preservation of specific cognitive or sensory modules, such as vision and language comprehension. These findings provide a simple and objective metabolic marker of consciousness, which can readily be implemented clinically. The direct correlation between brain metabolism and behavior further suggests that DOCs can fundamentally be understood as pathological neuroenergetic conditions and provide a unifying physiological basis for these syndromes.
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Affiliation(s)
- Johan Stender
- BRAINlab, Department of Neuroscience & Pharmacology, Panum Institute, University of Copenhagen, Nørre Allé 10, 2200 Copenhagen, Denmark; Cyclotron Research Center and Department of Neurology, CHU Sart Tilman, University of Liège, Avenue de l'hôpital 11, 4000 Liège, Belgium
| | - Kristian Nygaard Mortensen
- BRAINlab, Department of Neuroscience & Pharmacology, Panum Institute, University of Copenhagen, Nørre Allé 10, 2200 Copenhagen, Denmark
| | - Aurore Thibaut
- Cyclotron Research Center and Department of Neurology, CHU Sart Tilman, University of Liège, Avenue de l'hôpital 11, 4000 Liège, Belgium
| | - Sune Darkner
- Department of Computer Science, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Steven Laureys
- Cyclotron Research Center and Department of Neurology, CHU Sart Tilman, University of Liège, Avenue de l'hôpital 11, 4000 Liège, Belgium
| | - Albert Gjedde
- BRAINlab, Department of Neuroscience & Pharmacology, Panum Institute, University of Copenhagen, Nørre Allé 10, 2200 Copenhagen, Denmark
| | - Ron Kupers
- BRAINlab, Department of Neuroscience & Pharmacology, Panum Institute, University of Copenhagen, Nørre Allé 10, 2200 Copenhagen, Denmark; Department of Radiology & Biomedical Imaging, Yale University, 300 Cedar Street, New Haven, CT 06520, USA.
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May TL, Seder DB, Fraser GL, Stone P, McCrum B, Riker RR. Moderate-dose sedation and analgesia during targeted temperature management after cardiac arrest. Neurocrit Care 2016; 22:105-11. [PMID: 24962894 DOI: 10.1007/s12028-014-9998-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Sedation and analgesia regimens during targeted temperature management (TTM), after cardiac arrest varies widely, are poorly described in the literature and may have a negative impact on outcome. Since implementing TTM in 2005, we have used moderate-dose sedation and describe our experience with this approach. METHODS In this retrospective review, we included patients treated with TTM for cardiac arrest at our institution for 2008-2012. Patients received TTM if they did not follow verbal commands following cardiac arrest, regardless of place of arrest or rhythm. Utstein-compatible data were prospectively entered into the International Cardiac Arrest Registry, supplemented by review of nursing, pharmacy, and physical therapy records. We report analgesic and sedative medications and doses during the 24 h of active TTM at 33 °C, resource utilization, and important clinical events. RESULTS 166 patients treated with TTM after in- and out-of-hospital cardiac arrest with complete data were included. Overall survival was 42 %, median time to following commands was 3 h after rewarming (-6, 14), time to spontaneous breathing trial was 19 h (5-35), time to extubation was 28 h (9-60), and 59 % of survivors were discharged directly home at 13 (10-20) days. The incidence of seizure was 6 %, septic shock 4 %, and pneumonia 32 %. Four survivors required tracheostomy at 8, 8, 12, and 16 days. CONCLUSIONS A moderate-dose sedation and analgesia regimen was well tolerated and effective during therapeutic hypothermia after cardiac arrest and is an effective alternative to very deep sedation. We recommend more complete description of sedation and analgesia protocols in future studies, including expanded outcome reporting to include variables affected by sedation therapy. Further study is required to define which sedation approach for TTM may be best.
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Affiliation(s)
- Teresa L May
- Division of Pulmonary and Critical Care Medicine, Maine Medical Center, 22 Bramhall St, Portland, ME, 04102, USA,
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Kim TK, Cho YJ, Min JJ, Murkin JM, Bahk JH, Hong DM, Jeon Y. Tissue microcirculation measured by vascular occlusion test during anesthesia induction. J Clin Monit Comput 2015; 30:41-50. [PMID: 25750016 DOI: 10.1007/s10877-015-9679-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 02/27/2015] [Indexed: 11/27/2022]
Abstract
Tissue microcirculation measured by vascular occlusion test is impaired during septic shock. However, it has not been investigated extensively during anesthesia induction. The aim of the study is to evaluate tissue microcirculation during anesthesia induction. We hypothesized that during anesthesia induction, tissue microcirculation measured by vascular occlusion test might be enhanced with peripheral vasodilation during anesthesia induction. We conducted a prospective observational study of 50 adult patients undergoing cardiac surgery. During anesthesia induction, we measured and analyzed tissue oxygen saturation, vascular occlusion test, cerebral oximetry, forearm-minus-fingertip skin temperature gradients and hemodynamic data in order to evaluate microcirculation as related to alterations in peripheral vasodilation as reflected by increased Tforearm-finger thermal gradients. During anesthesia induction, recovery slope during vascular occlusion test and cerebral oxygen saturation increased from 4.0 (1.5) to 4.7 (1.3) % s(-1) (p = 0.02) and 64.0 (10.2) to 74.2 (9.2) % (p < 0.001), respectively. Forearm-minus-fingertip skin temperature gradients decreased from 1.9 (2.9) to -1.4 (2.2) °C (p < 0.001). There was an inverse correlation between changes in the skin temperature gradients and changes in cerebral oximetry (r = 0.33; p = 0.02). During anesthesia induction, blood pressure and forearm-minus-fingertip skin temperature gradients decrease while cerebral oximetry and vascular occlusion test recovery slope increase. These findings suggest that anesthesia induction increases tissue microcirculation with peripheral vasodilation.
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Affiliation(s)
- Tae Kyong Kim
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Daehakro 101, Jongno-gu, Seoul, 110-744, Korea
| | - Youn Joung Cho
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Daehakro 101, Jongno-gu, Seoul, 110-744, Korea
| | - Jeong Jin Min
- Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Seoul, Korea
| | - John M Murkin
- Department of Anesthesiology and Perioperative Medicine, Schulich School of Medicine, University of Western Ontario, London, ON, Canada
| | - Jae-Hyon Bahk
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Daehakro 101, Jongno-gu, Seoul, 110-744, Korea
| | - Deok Man Hong
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Daehakro 101, Jongno-gu, Seoul, 110-744, Korea
| | - Yunseok Jeon
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Daehakro 101, Jongno-gu, Seoul, 110-744, Korea.
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Andrzejowski JC, Wiles MD. Was NAP5 ‘NICE’ enough; where next for depth of anaesthesia monitors? Anaesthesia 2015; 70:514-8. [DOI: 10.1111/anae.13045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
| | - M. D. Wiles
- Sheffield Teaching Hospitals NHS Foundation Trust; Sheffield UK
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Smith MMJ. BiSpectral Index (BIS) monitoring may detect critical hypotension before automated non-invasive blood pressure (NIBP) measurement during general anaesthesia; a case report. F1000Res 2015; 3:5. [PMID: 25580217 PMCID: PMC4038321 DOI: 10.12688/f1000research.3-5.v1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/09/2014] [Indexed: 12/02/2022] Open
Abstract
A patient undergoing general anaesthesia for neurosurgery exhibited an unexpected sudden decrease in the BiSpectral Index (BIS) value to near-zero. This prompted the detection of profound hypotension using non-invasive blood pressure (NIBP) measurement and expedited urgent assessment and treatment, with the patient making a full recovery. Widely regarded as a ‘depth of anaesthesia’ monitor, this case demonstrates the potential extra clinical benefit BIS may have in the detection of critical incidents such as anaphylaxis during general anaesthesia.
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Affiliation(s)
- Matthew M J Smith
- Department of Anaesthetics, Sheffield Teaching Hospitals, Sheffield, S10 2JF, UK
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Flores A, Ribó M, Rubiera M, Gonzalez-Cuevas M, Pagola J, Rodriguez-Luna D, Muchada M, Kallas J, Meler P, Sanjuan E, Alvarez-Sabin J, Montaner J, Molina CA. Monitoring of Cortical Activity Postreperfusion. A Powerful Tool for Predicting Clinical Response Immediately After Recanalization. J Neuroimaging 2014; 25:257-262. [DOI: 10.1111/jon.12113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 12/01/2013] [Accepted: 01/27/2014] [Indexed: 11/27/2022] Open
Affiliation(s)
- Alan Flores
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - Marc Ribó
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - Marta Rubiera
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - Montserrat Gonzalez-Cuevas
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - Jorge Pagola
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - David Rodriguez-Luna
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - Marián Muchada
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - Julia Kallas
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - Pilar Meler
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - Estela Sanjuan
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - Jose Alvarez-Sabin
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - Joan Montaner
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
| | - Carlos A. Molina
- Stroke Unit, Department of Neurology, Vall d’Hebron University Hospital, Vall d’Hebron Research Institute, Departament de Medicina; Universitat Autonoma de Barcelona; Barcelona Spain
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Pillay S, Vizuete J, Liu X, Juhasz G, Hudetz AG. Brainstem stimulation augments information integration in the cerebral cortex of desflurane-anesthetized rats. Front Integr Neurosci 2014; 8:8. [PMID: 24605091 PMCID: PMC3932553 DOI: 10.3389/fnint.2014.00008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Accepted: 01/13/2014] [Indexed: 11/16/2022] Open
Abstract
States of consciousness have been associated with information integration in the brain as modulated by anesthesia and the ascending arousal system. The present study was designed to test the hypothesis that electrical stimulation of the oral part of the pontine reticular nucleus (PnO) can augment information integration in the cerebral cortex of anesthetized rats. Extracellular unit activity and local field potentials were recorded in freely moving animals from parietal association (PtA) and secondary visual (V2) cortices via chronically implanted microwire arrays at three levels of anesthesia produced by desflurane: 3.5, 4.5, and 6.0% (where 4.5% corresponds to that critical for the loss of consciousness). Information integration was characterized by integration (multiinformation) and interaction entropy, estimated from the statistical distribution of coincident spike patterns. PnO stimulation elicited electrocortical activation as indicated by the reductions in δ- and θ-band powers at the intermediate level of anesthesia. PnO stimulation augmented integration from 1.13 ± 0.03 to 6.12 ± 1.98 × 103 bits and interaction entropy from 0.44 ± 0.11 to 2.18 ± 0.72 × 103 bits; these changes were most consistent in the PtA at all desflurane concentrations. Stimulation of the retina with discrete light flashes after PnO stimulation elicited an additional 166 ± 25 and 92 ± 12% increase in interaction entropy in V2 during light and intermediate levels. The results suggest that the PnO may modulate spontaneous ongoing and sensory stimulus-related cortical information integration under anesthesia.
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Affiliation(s)
- Siveshigan Pillay
- Department of Anesthesiology, Medical College of Wisconsin Milwaukee, WI, USA
| | - Jeannette Vizuete
- Department of Anesthesiology, Medical College of Wisconsin Milwaukee, WI, USA
| | - Xiping Liu
- Department of Anesthesiology, Medical College of Wisconsin Milwaukee, WI, USA
| | - Gabor Juhasz
- Laboratory of Proteomics, Institute of Biology, Eötvös Loránd University Budapest, Hungary
| | - Anthony G Hudetz
- Department of Anesthesiology, Medical College of Wisconsin Milwaukee, WI, USA
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Abstract
How does general anesthesia (GA) work? Anesthetics are pharmacological agents that target specific central nervous system receptors. Once they bind to their brain receptors, anesthetics modulate remote brain areas and end up interfering with global neuronal networks, leading to a controlled and reversible loss of consciousness. This remarkable manipulation of consciousness allows millions of people every year to undergo surgery safely most of the time. However, despite all the progress that has been made, we still lack a clear and comprehensive insight into the specific neurophysiological mechanisms of GA, from the molecular level to the global brain propagation. During the last decade, the exponential progress in neuroscience and neuro-imaging led to a significant step in the understanding of the neural correlates of consciousness, with direct consequences for clinical anesthesia. Far from shutting down all brain activity, anesthetics lead to a shift in the brain state to a distinct, highly specific and complex state, which is being increasingly characterized by modern neuro-imaging techniques. There are several clinical consequences and challenges that are arising from the current efforts to dissect GA mechanisms: the improvement of anesthetic depth monitoring, the characterization and avoidance of intra-operative awareness and post-anesthesia cognitive disorders, and the development of future generations of anesthetics.
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Affiliation(s)
- L Uhrig
- CEA, NeuroSpin center, 91191 Gif-sur-Yvette, France; Avenir-Bettencourt-Schueller, Inserm, 91191 Gif-sur-Yvette, France; Cognitive neuroimaging unit, Inserm, U992, 91191 Gif-sur-Yvette, France.
| | - S Dehaene
- CEA, NeuroSpin center, 91191 Gif-sur-Yvette, France; Cognitive neuroimaging unit, Inserm, U992, 91191 Gif-sur-Yvette, France; Collège de France, 75231 Paris, France; Université Paris-Sud, 91405 Orsay, France
| | - B Jarraya
- CEA, NeuroSpin center, 91191 Gif-sur-Yvette, France; Avenir-Bettencourt-Schueller, Inserm, 91191 Gif-sur-Yvette, France; Neuromodulation unit, department of neurosurgery, Foch Hospital, 92150 Suresnes, France; Université Versailles Saint-Quentin-en-Yvelines, 78000 Versailles, France
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Abstract
Applying scalp sensors in the operating theater, intensive care, or resuscitation scenarios to detect and monitor brain function is achievable, practical, and affordable. The modalities are complex and the output of the monitor needs careful interpretation. The monitor may have technical problems, and a single reading must be considered with caution. These monitors may have a use for monitoring trends in specific situations, but evidence does not support their widespread use. Nevertheless, research should continue to investigate their role. Future techniques and treatments may show that these monitors can monitor brain function and prevent harm.
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Affiliation(s)
- Michael Sury
- Department of Anaesthesia, Great Ormond Street Hospital, Great Ormond Street, London WC1N 3JH, UK.
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Tsaousi GG, Pitsis AA, Deliaslani DV, Amaniti EN, Karakoulas KA, Vasilakos DG. Cerebral Oxygenation Impairment and S-100β Protein Release During Off-Pump Coronary Artery Revascularization. J Cardiothorac Vasc Anesth 2013; 27:245-52. [DOI: 10.1053/j.jvca.2012.06.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Indexed: 11/11/2022]
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ZEIDAN A, MAZOIT JX. Minimal alveolar concentration of sevoflurane for maintaining bispectral index below 50 in morbidly obese patients. Acta Anaesthesiol Scand 2013; 57:474-9. [PMID: 23252750 DOI: 10.1111/aas.12038] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/2012] [Indexed: 11/29/2022]
Abstract
BACKGROUND Morbid obesity is associated with important differences in pharmacokinetics and pharmacodynamics. The aim of this study was to determine minimum alveolar concentration of sevoflurane for maintaining bispectral index (BIS) below 50 (MACBIS50 ) in morbidly obese patients undergoing bariatric surgery using the Continual Reassessment Method (CRM) method. METHODS Twenty-four morbidly obese patients (body mass index 40-70 kg/m(2) ) were enrolled in our study. Twenty minutes following pre-medication with fentanyl 100 μg, general anaesthesia was induced using propofol 2 mg/kg and cisatracurium 2 mg/kg to facilitate tracheal intubation. The lowest BIS score was recorded following induction. Thereafter, when BIS began to increase > 60, maintenance of anaesthesia was started with a pre-determined end-tidal sevoflurane concentration (ET Sevo) and maintained for 10 min followed by 1-min assessment of BIS taken at 10-s intervals to determine the ET Sevo. The ET Sevo leading to a probability close to 80% success was calculated using the CRM, and the MACBIS50 leading to 50% success was calculated by fitting the data to a dose-probability sigmoid curve, respectively. RESULTS The ET Sevo able to maintain BIS value below 50 was 1.8% in 67% [95% confidence interval (CI) 0.44-0.86] and higher in the remaining 33% of the patients and the ET Sevo leading to a BIS value below 50 in 50% of the patients (MACBIS50 ) was 1.6 ± 0.10%. CONCLUSIONS The calculated values (1.8% and 1.6%) were higher than that previously reported in normal adult patients (0.97%; 95% CI 0.89-1.1%) and less than that reported in children (2.8%; 95% CI 2.7-3.1%).
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Affiliation(s)
- A. ZEIDAN
- Department of Anaesthesiology; Procare Riaya Hospital; Al-Khobar; Kingdom of Saudi Arabia
| | - J. X. MAZOIT
- Laboratoire d'Anesthésie INSERM UMR788 Université Paris-Sud and Département d'Anesthésie-Réanimation; Hôpitaux Universitaires Paris-Sud; AP-HP Le Kremlin Bicêtre; France
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Hyder F, Fulbright RK, Shulman RG, Rothman DL. Glutamatergic function in the resting awake human brain is supported by uniformly high oxidative energy. J Cereb Blood Flow Metab 2013; 33:339-47. [PMID: 23299240 PMCID: PMC3587823 DOI: 10.1038/jcbfm.2012.207] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Rodent (13)C magnetic resonance spectroscopy studies show that glutamatergic signaling requires high oxidative energy in the awake resting state and allowed calibration of functional magnetic resonance imaging (fMRI) signal in terms of energy relative to the resting energy. Here, we derived energy used for glutamatergic signaling in the awake resting human. We analyzed human data of electroencephalography (EEG), positron emission tomography (PET) maps of oxygen (CMR(O2)) and glucose (CMR(glc)) utilization, and calibrated fMRI from a variety of experimental conditions. CMR(glc) and EEG in the visual cortex were tightly coupled over several conditions, showing that the oxidative demand for signaling was four times greater than the demand for nonsignaling events in the awake state. Variations of CMR(O2) and CMR(glc) from gray-matter regions and networks were within ±10% of means, suggesting that most areas required similar energy for ubiquitously high resting activity. Human calibrated fMRI results suggest that changes of fMRI signal in cognitive studies contribute at most ±10% CMR(O2) changes from rest. The PET data of sleep, vegetative state, and anesthesia show metabolic reductions from rest, uniformly >20% across, indicating no region is selectively reduced when consciousness is lost. Future clinical investigations will benefit from using quantitative metabolic measures.
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Affiliation(s)
- Fahmeed Hyder
- Magnetic Resonance Research Center, Yale University, New Haven, Connecticut 06520, USA.
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Walter B, Eiselt M, Cumming P, Xiong G, Hinz R, Uthe S, Brust P, Bauer R. Resistance of brain glucose metabolism to thiopental-induced CNS depression in newborn piglets. Int J Dev Neurosci 2013; 31:157-64. [PMID: 23305916 DOI: 10.1016/j.ijdevneu.2012.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2012] [Accepted: 12/30/2012] [Indexed: 10/27/2022] Open
Abstract
The transition from mild sedation to deep anaesthesia is marked by the phenomenon of burst suppression (BS). FDG-PET studies show that the cerebral metabolic rate for glucose (CMRglc) declines dramatically with onset of BS in the adult brain. Global CMRglc increases substantially in the post-natal period and achieves its maximum in preadolescence. However, the impact of post-natal brain development on the vulnerability of CMRglc to the onset of BS has not been documented. Therefore, cerebral blood flow and metabolism were measured using a variant of the Kety-Schmidt method, in conjunction with quantitative regional estimation of brain glucose uptake by FDG-PET in groups of neonate and juvenile pigs, under a condition of light sedation or after induction of deep anaesthesia with thiopental. Quantification of simultaneous ECoG recordings was used to establish the correlation between anaesthesia-related changes in brain electrical activity and the observed cerebrometabolic changes. In the condition of light sedation the magnitude of CMRglc was approximately 20% higher in the older pigs, with the greatest developmental increase evident in the cerebral cortex and basal ganglia (P<0.05). Onset of BS was associated with 20-40% declines in CMRglc. Subtraction of the mean parametric maps for CMRglc showed the absolute reductions in CMRglc evoked by thiopental anaesthesia to be two-fold greater in the pre-adolescent pigs than in the neonates (P<0.05). Thus, the lesser suppression of brain energy demand of neonate brain during deep anaesthesia represents a reduced part of thiopental suppressing brain metabolism in neonates.
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Affiliation(s)
- Bernd Walter
- Institute of Molecular Cell Biology, Jena University Hospital, Friedrich Schiller University, Jena, Germany
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Herreras Gutiérrez JL, Gilsanz Rodríguez F. [Pneumocephalus as a cause of a decrease in the bispectral index]. ACTA ACUST UNITED AC 2012; 61:43-6. [PMID: 23261226 DOI: 10.1016/j.redar.2012.10.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 10/15/2012] [Accepted: 10/22/2012] [Indexed: 11/16/2022]
Abstract
A sharp decrease in the values of the bispectral index (BIS), along with an increase in suppression rate, was observed in a patient after the removal of an epidermoid tumor in the cerebellopontine angle by right retrosigmoid access under general anesthesia. This was probably related to a frontal pneumocephalus. No accompanying neurological signs were observed. The patient was extubated in the Recovery Room with no further incidents, as the BIS increased again. The neurosurgeons chose conservative treatment, relying on the reabsorption and redistribution of the air.
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Affiliation(s)
| | - F Gilsanz Rodríguez
- Servicio de Anestesia y Reanimación, Hospital Universitario La Paz, Madrid, España
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Klein K, Fukui K, Schramm P, Stadie A, Fischer G, Werner C, Oertel J, Engelhard K. Human cerebral microcirculation and oxygen saturation during propofol-induced reduction of bispectral index †. Br J Anaesth 2011; 107:735-41. [DOI: 10.1093/bja/aer227] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Kim SJ, Kwon JY, Cho AR, Kim HK, Kim TK. The effects of sevoflurane and propofol anesthesia on cerebral oxygenation in gynecological laparoscopic surgery. Korean J Anesthesiol 2011; 61:225-32. [PMID: 22025945 PMCID: PMC3198184 DOI: 10.4097/kjae.2011.61.3.225] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Revised: 03/28/2011] [Accepted: 04/05/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Both the Trendelenburg position and pneumoperitoneum with carbon dioxide have been reported to increase intracranial pressure (ICP) and to alter cerebral blood flow or cerebral blood volume. Also anesthetic agents have variable effects on cerebral hemodynamics and ICP. The present study was conducted to determine whether regional cerebral oxygen saturation (rSO(2)) values differ between propofol and sevoflurane anesthesia during laparoscopic surgery in the Trendelenburg position. METHODS Thirty-two adult women undergoing gynecological laparoscopic surgery were divided into sevoflurane and propofol groups. rSO(2) values were recorded at 10 min after induction in the neutral position (Tpre), 10 min after the pneumoperitoneum in the Trendelenburg position (Tpt) and 10 min after desufflation in the neutral position (Tpost). For analysis of rSO(2), we did ANOVA and univariate two-way ANCOVA with covariates being mean arterial pressure and end tidal carbon dioxide tension. RESULTS Between sevoflurane and propofol groups, the change in rSO(2) was significantly different even after ANCOVA. rSO(2) at Tpt (76.3 ± 5.9% in sevoflurane vs 69.4 ± 5.8% in propofol) and Tpost (69.5 ± 7.1% in sevoflurane vs 63.8 ± 6.6% in propofol) were significantly higher in the sevoflurane group compared with the propofol group. In the propofol group, rSO(2) at Tpost was significantly lower than at Tpre (71.1 ± 4.8%) and cerebral oxygen desaturation occurred in two patients (14.3%). CONCLUSIONS Significantly lower rSO(2) values were observed in the propofol group during gynecological laparoscopic surgery. The possibility of cerebral oxygen desaturation should not be overlooked during propofol anesthesia even after desufflation of the abdomen in the neutral position.
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Affiliation(s)
- Sung-Jin Kim
- Department of Anesthesia and Pain Medicine, Pusan National University Hospital, Busan, Korea
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Deeper total intravenous anesthesia reduced the incidence of early postoperative cognitive dysfunction after microvascular decompression for facial spasm. J Neurosurg Anesthesiol 2011; 23:12-7. [PMID: 21252704 DOI: 10.1097/ana.0b013e3181f59db4] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
OBJECTIVE To investigate whether the depth of total intravenous anesthesia affects postoperative cognitive dysfunction. METHODS Ninety-six patients with facial spasm who were scheduled to receive microvascular decompression were randomly divided into 2 groups: deeper anesthesia (n = 50) and lighter anesthesia (n = 46). Exclusion criteria included: a history of neurologic or mental disease, serum creatinine in excess of 177 μmol/L, active liver disease, cardiac dysfunction, pulmonary dysfunction, endocrine disease, metabolic disease, a history of surgery, fewer than 6 years of school, inability to complete neuropsychologic testing, vision dysfunction, and auditory dysfunction. Propofol and sufentanil were used for anesthesia induction and propofol and remifentanil were used for the maintenance of anesthesia. A battery of 9 neuropsychologic was administered preoperatively and 5 days after surgery. A postoperative deficit was defined as a postop decrement to preop score greater than 1 standard deviation on any test. Patients who experienced 2 or more deficits were deemed to have early postoperative cognitive dysfunction. RESULTS Eighty patients completed both preoperative and postoperative neuropsychologic testing, of which 40 each were in the deeper and lighter anesthesia group. Postoperative early cognitive dysfunction occurred in 4 patients (10%) in the deeper anesthesia group and in 11 patients (27.5%) in the lighter anesthesia group. The incidence of the postoperative cognitive dysfunction was significantly reduced in the deeper anesthesia group compared with the lighter anesthesia group (P < 0.05, χ). CONCLUSION Deeper total intravenous anesthesia can decrease the incidence of cognitive dysfunction in the early postoperative period.
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Mechanisms of general anesthetic action: Focus on the cellular network. Transl Neurosci 2011. [DOI: 10.2478/s13380-011-0022-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractThe discovery of general anesthetics had a tremendous impact on development of surgery and medicine in general, during the last century. Despite the widespread use of general anesthetics, the mechanisms by which they produce their effects in the central nervous system are still poorly understood. Over the past decade, several new findings have contributed significantly to a better understanding of general anesthetic mechanisms. The current review summarizes recent data on different anesthetic neuronal targets that might be involved in the mechanism of action of general anesthetics, giving special attention to the importance of binding pockets for anesthetics within transmembrane receptors and cellular signaling leading to morphological changes of neuronal cells. Several lines of evidence suggest that disruption in brain network connectivity is important for anaesthesia-induced loss of consciousness and this is discussed in relation to morphological changes.
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Newman A, Boyd C, Meyers D, Bonanno L. Implementation of Music as an Anesthetic Adjunct During Monitored Anesthesia Care. J Perianesth Nurs 2010; 25:387-91. [DOI: 10.1016/j.jopan.2010.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Revised: 09/07/2010] [Accepted: 10/05/2010] [Indexed: 10/18/2022]
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Lee MS, Ko J, Lee AR, Lee IH, Jung MA, Austin B, Chung H, Nahm S, Eom K. Effects of anesthetic protocol on normal canine brain uptake of 18F-FDG assessed by PET/CT. Vet Radiol Ultrasound 2010; 51:130-5. [PMID: 20402395 DOI: 10.1111/j.1740-8261.2009.01636.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
The purpose of this study was to assess the effects of four anesthetic protocols on normal canine brain uptake of 2-deoxy-2-[18F]fluoro-D-glucose (FDG) using positron emission tomography/computed tomography (PET/CT). Five clinically normal beagle dogs were anesthetized with (1) propofol/isoflurane, (2) medetomidine/pentobarbital, (3) xylazine/ketamine, and (4) medetomidine/tiletamine-zolazepam in a randomized cross-over design. The standard uptake value (SUV) of FDG was obtained in the frontal, parietal, temporal and occipital lobes, cerebellum, brainstem and whole brain, and compared within and between anesthetic protocols using the Friedman test with significance set at P < 0.05. Significant differences in SUVs were observed in various part of the brain associated with each anesthetic protocol. The SUV for the frontal and occipital lobes was significantly higher than in the brainstem in all dogs. Dogs receiving medetomidine/tiletamine-zolazepam also had significantly higher whole brain SUVs than the propofol/isoflurane group. We concluded that each anesthetic protocol exerted a different regional brain glucose uptake pattern. As a result, when comparing brain glucose uptake using PET/CT, one should consider the effects of anesthetic protocols on different regions of the glucose uptake in the dog's brain.
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Affiliation(s)
- Min Su Lee
- Department of Veterinary Diagnostic Imaging, the College of Veterinary Medicine, Konkuk University, Seoul, Korea
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Decrease in Bispectral Index Preceding Signs of Impending Brain Death in Traumatic Brain Injury. J Neurosurg Anesthesiol 2010; 22:268-9. [DOI: 10.1097/ana.0b013e3181d732c8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Kawaguchi H, Hirakawa K, Miyauchi K, Koike K, Ohno Y, Sakamoto A. Pattern recognition analysis of proton nuclear magnetic resonance spectra of brain tissue extracts from rats anesthetized with propofol or isoflurane. PLoS One 2010; 5:e11172. [PMID: 20567596 PMCID: PMC2887427 DOI: 10.1371/journal.pone.0011172] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Accepted: 05/27/2010] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND General anesthesia is routinely used as a surgical procedure and its safety has been endorsed by clinical outcomes; however, its effects at the molecular level have not been elucidated. General anesthetics influence glucose metabolism in the brain. However, the effects of anesthetics on brain metabolites other than those related to glucose have not been well characterized. We used a pattern recognition analysis of proton nuclear magnetic resonance spectra to visualize the changes in holistic brain metabolic phenotypes in response to the widely used intravenous anesthetic propofol and the volatile anesthetic isoflurane. METHODOLOGY/PRINCIPAL FINDINGS Rats were randomized into five groups (n = 7 each group). Propofol and isoflurane were administered to two groups each, for 2 or 6 h. The control group received no anesthesia. Brains were removed directly after anesthesia. Hydrophilic compounds were extracted from excised whole brains and measured by proton nuclear magnetic resonance spectroscopy. All spectral data were processed and analyzed by principal component analysis for comparison of the metabolite profiles. Data were visualized by plotting principal component (PC) scores. In the plots, each point represents an individual sample. The propofol and isoflurane groups were clustered separately on the plots, and this separation was especially pronounced when comparing the 6-h groups. The PC scores of the propofol group were clearly distinct from those of the control group, particularly in the 6-h group, whereas the difference in PC scores was more subtle in the isoflurane group and control groups. CONCLUSIONS/SIGNIFICANCE The results of the present study showed that propofol and isoflurane exerted differential effects on holistic brain metabolism under anesthesia.
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Affiliation(s)
- Hiroshi Kawaguchi
- Department of Anesthesiology, Nippon Medical School, Bunkyo-ku, Tokyo, Japan.
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Smith MMJ, Andrzejowski J. Effect of decompressive craniectomy on bispectral index and memory. Br J Anaesth 2010; 104:512. [PMID: 20228191 DOI: 10.1093/bja/aeq049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Doufas AG, Komatsu R, Orhan-Sungur M, Sengupta P, Wadhwa A, Mascha E, Shafer SL, Sessler DI. Neuromuscular Block Differentially Affects Immobility and Cortical Activation at Near–Minimum Alveolar Concentration Anesthesia. Anesth Analg 2009; 109:1097-104. [DOI: 10.1213/ane.0b013e3181af631a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Young Choi M, Soo Lee D, Hwang JM, Gyu Choi D, Lee KM, Park K, Suk Yu Y, Chung H. Investigation of visual cortex in children with cortical visual impairment: positron emission tomography. Neuroophthalmology 2009. [DOI: 10.1076/noph.25.3.103.7129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Abstract
An individual, human or animal, is defined to be in a conscious state empirically by the behavioral ability to respond meaningfully to stimuli, whereas the loss of consciousness is defined by unresponsiveness. PET measurements of glucose or oxygen consumption show a widespread approximately 45% reduction in cerebral energy consumption with anesthesia-induced loss of consciousness. Because baseline brain energy consumption has been shown by (13)C magnetic resonance spectroscopy to be almost exclusively dedicated to neuronal signaling, we propose that the high level of brain energy is a necessary property of the conscious state. Two additional neuronal properties of the conscious state change with anesthesia. The delocalized fMRI activity patterns in rat brain during sensory stimulation at a higher energy state (close to the awake) collapse to a contralateral somatosensory response at lower energy state (deep anesthesia). Firing rates of an ensemble of neurons in the rat somatosensory cortex shift from the gamma-band range (20-40 Hz) at higher energy state to <10 Hz at lower energy state. With the conscious state defined by the individual's behavior and maintained by high cerebral energy, measurable properties of that state are the widespread fMRI patterns and high frequency neuronal activity, both of which support the extensive interregional communication characteristic of consciousness. This usage of high brain energies when the person is in the "state" of consciousness differs from most studies, which attend the smaller energy increments observed during the stimulations that form the "contents" of that state.
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Purdon PL, Pierce ET, Bonmassar G, Walsh J, Harrell PG, Kwo J, Deschler D, Barlow M, Merhar RC, Lamus C, Mullaly CM, Sullivan M, Maginnis S, Skoniecki D, Higgins HA, Brown EN. Simultaneous electroencephalography and functional magnetic resonance imaging of general anesthesia. Ann N Y Acad Sci 2009; 1157:61-70. [PMID: 19351356 DOI: 10.1111/j.1749-6632.2008.04119.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
It has been long appreciated that anesthetic drugs induce stereotyped changes in electroencephalogram (EEG), but the relationships between the EEG and underlying brain function remain poorly understood. Functional imaging methods including positron emission tomography (PET) and functional magnetic resonance imaging (fMRI), have become important tools for studying how anesthetic drugs act in the human brain to induce the state of general anesthesia. To date, no investigation has combined functional MRI with EEG to study general anesthesia. We report here a paradigm for conducting combined fMRI and EEG studies of human subjects under general anesthesia. We discuss the several technical and safety problems that must be solved to undertake this type of multimodal functional imaging and show combined recordings from a human subject. Combined fMRI and EEG exploits simultaneously the high spatial resolution of fMRI and the high temporal resolution of EEG. In addition, combined fMRI and EEG offers a direct way to relate established EEG patterns induced by general anesthesia to changes in neural activity in specific brain regions as measured by changes in fMRI blood oxygen level dependent (BOLD) signals.
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Affiliation(s)
- Patrick L Purdon
- Department of Anesthesia and Critical Care, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
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Abstract
In 1947, a second power of anesthesia was described: "With anesthetic agents we seem to have a tool for producing and holding at will, and at little risk, different levels of consciousness--a tool that promises to be of great help in studies of mental phenomena." In 1995, anesthetic manipulation was coupled with neuroimaging, paving the way for detailed assessments of the relationship between the structure and the functioning of the brain. Anesthesia combined with neuroimaging thus provides a unique tool for investigating the neural correlates of human cognition.
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Affiliation(s)
- M T Alkire
- Department of Anesthesiology, University of California, Irvine, California, USA
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