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INTENSIVE CARE in NEUROLOGY and NEUROSURGERY Pathophysiological Basis for the Management of Acute Cerebral Injury

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INTENSIVE CARE in NEUROLOGY and NEUROSURGERY Pathophysiological Basis for the Management of Acute Cerebral Injury Daniel Agustín Godoy INTENSIVE CARE IN NEUROLOGY AND NEUROSURGERY Pathophysiological Basis for the Management of Acute Cerebral Injury VOLUME 1 Head Editor Daniel Agustín Godoy, MD, FCCM Neurointensive Care Unit- Sanatorio Pasteur Intensive Care Unit Hospital Interzonal de Agudos ‘’San Juan Bautista’’ Catamarca. Argentina Associate Editor Gustavo Rene Piñero, MD, FCCM Intensive Care Unit Hospital Municipal ‘’Leonidas Lucero’’ Assistant Professor Critical and Emergency MedicineHealth Sciences Department - South University Bahia Blanca, Buenos Aires. Argentina © SEEd srl. All rights reserved Piazza Carlo Emanuele II, 19 – 10123 Torino, Italy Tel. 011.566.02.58 – Fax 011.518.68.92 www.edizioniseed.it [email protected] First edition February 2013 VOLUME 1 ISBN 978-88-9741-939-6 Printed on acid-free paper by Tipografia Graphot, Torino (Italy) Although the information about medication given in this book has been carefully checked, the author and publisher accept no liability for the accuracy of this information. In every individual case the user must check such information by consulting the relevant literature. This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcast- ing, reproduction on microfilm or in any other way, and storage in data banks. Duplication of this publi- cation or parts thereof is permitted only under the provisions of the Italian Copyright Law in its current version, and permission for use must always be obtained from SEEd Medical Publishers Srl. Violations are liable to prosecution under the Italian Copyright Law. To my parents Mirtha and Justino for giving me the life, education and the opportunity to study and acquire this wonderful profession. To my kids, Facundo, Luciano, Josefina and Alvaro who have suffered my absences and for all the love given me every day. To Veronica, my love, my friend, my support, guidance, and containment with whom if God willing I share what I have left. To all my colleagues and friends who have shared with me over than 23 years of hard and tireless work, uncertainties, anxieties, sorrows and joys in the Intensive Care Units where I have worked. To the life... Table of Contents Prologue ........................................................................................................................XV Preface ........................................................................................................................XVII References.........................................................................................................XVII SECTION 1. Introduction to Neuroinjury 1 Neuroscience Critical Care: Two Experts’ Point of View ................................................ 3 1.1 History, Organization, and Vision for the Future: Prof. Mirski’s Point of View ......3 1.2 NICU Organization: Past, Present and Future: Prof. Robertson’s Point of View .. 10 References........................................................................................................... 20 2 Basic Anatomy Applied to the Interpretation of Axial Tomography of the Brain in Emergency Medicine ............................................................................27 2.1 Introduction ........................................................................................................ 27 2.2 Development....................................................................................................... 27 2.3 Key Concepts ....................................................................................................... 36 2.4 Appendix: Images ................................................................................................ 36 References........................................................................................................... 51 General References ............................................................................................. 51 3 Physiological Basis for the Correct Interpretation of Different Situations in Acute Cerebral Injury ................................................................................................ 53 3.1 Functional and Structural Organization of the Nervous System .........................53 3.2 The Blood-Brain Barrier (BBB) .............................................................................55 3.3 Cerebrospinal Fluid (CSF) ....................................................................................56 3.4 Aquaporins (AQP)................................................................................................ 57 3.5 Intracranial Pressure ........................................................................................... 58 3.6 Cerebral Volume/Pressure Curve (V/P). Cerebral Compliance ............................59 3.7 Intracranial Pressure Curve .................................................................................60 3.8 Cerebral Oxygen Metabolism ..............................................................................61 3.9 Cerebral Blood Flow (CBF)...................................................................................62 3.10 Oxygen Tissue Pressure (ptiO2) ...........................................................................64 3.11 Cerebral Glucose Metabolism .............................................................................65 3.12 Cerebral Temperature ......................................................................................... 65 3.13 Brain-systemic Temperature Gradient ................................................................66 3.14 Concept of Primary and Secondary Injury ..........................................................68 General References ............................................................................................. 68 4 Examination of the Critically Ill Neurological Patient .................................................. 71 4.1 Clinical Evaluation (or Examination) of the Critically Ill Neurological Patient .....71 4.2 General Examination ........................................................................................... 72 4.3 Comprehensive Neurological Examination .........................................................74 4.4 Routine Investigations of the Neurocritical Patient ............................................74 V Intensive Care in Neurology and Neurosurgery 4.5 Focused Neurological Examination of Selected Topics .......................................75 References......................................................................................................... 101 General References ...........................................................................................102 5 Evaluation Scales in Neurocritically Ill Patients ......................................................... 105 5.1 Objectives ......................................................................................................... 105 5.2 Introduction ...................................................................................................... 105 5.3 Evaluation in the Acute Phase ...........................................................................105 5.4 Imaging-based Assessment Scales ....................................................................114 5.5 Scale of Evolution, Evaluation of Consciousness in Advanced Stages of Brain Injury Outcome Scales .........................................................................123 General References ...........................................................................................129 SECTION 2. Neuromonitoring 6 Neuroimage Monitoring in the Management of Neurocritical Care Patients ...........135 6.1 Introduction ...................................................................................................... 135 6.2 CT in Head-injured Patients...............................................................................137 6.3 CT in Patients With Cerebrovascular Hemorrhagic Disease ..............................145 6.4 CT in the Diagnosis of Acute Ischemic Cerebrovascular Diseases ....................152 6.5 Conclusions ....................................................................................................... 156 References......................................................................................................... 156 7 Intracranial Pressure Monitoring. Acute Cerebral Injury: the First 48 Hours ...........159 7.1 Intracranial Pressure .........................................................................................159 7.2 Techniques for Monitoring Intracranial Pressure ..............................................160 7.3 The ICP Waveform ............................................................................................. 161 7.4 Elevated Intracranial Pressure and Pressure Waves ..........................................163 7.5 Cerebral Perfusion Pressure ..............................................................................165 7.6 Cerebral Autoregulation ....................................................................................165 7.7 Indications for ICP Monitoring ..........................................................................166 7.8 Conclusions ....................................................................................................... 166 References........................................................................................................
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