This e-book will review special features of the cerebral circulation and how they contribute to the physiology of the brain. It describes structural and functional properties of the cerebral circulation that are unique to the brain, an organ with high metabolic demands and the need for tight water and ion homeostasis. Autoregulation is pronounced in the brain, with myogenic, metabolic and neurogenic mechanisms contributing to maintain relatively constant blood flow during both increases and decreases in pressure. In addition, unlike peripheral organs where the majority of vascular resistance resides in small arteries and arterioles, large extracranial and intracranial arteries contribute significantly to vascular resistance in the brain. The prominent role of large arteries in cerebrovascular resistance helps maintain blood flow and protect downstream vessels during changes in perfusion pressure. The cerebral endothelium is also unique in that its barrier properties are in some way more like epithelium than endothelium in the periphery. The cerebral endothelium, known as the blood-brain barrier, has specialized tight junctions that do not allow ions to pass freely and has very low hydraulic conductivity and transcellular transport. This special configuration modifies Starling's forces in the brain microcirculation such that ions retained in the vascular lumen oppose water movement due to hydrostatic pressure. Tight water regulation is necessary in the brain because it has limited capacity for expansion within the skull. Increased intracranial pressure due to vasogenic edema can cause severe neurologic complications and death.

Studies of the mechanisms relating blood supply to the brain appeared to be, in some sense, at a deadlock. Despite extensive application of different methodical approaches, no qualitative progress has been observed in these studies at the present time. This is perhaps due to the traditional, but not understandable, separation of neurophysiological and "circulatory" studies. It may seem very paradoxical, but the study of cerebral blood circulation proceeds almost in complete isolation from the knowledge about brain functions and does not take into account the specificity of the working brain as a part of the whole body. This book comprehensively addresses the issues of blood flow regulation. It is well known that the brain belongs to the group of organs having a high level of oxygen consumption. Oxygen consumption by the brain is an average 4.6 ml per 100 g of tissue per minute. In humans, the level of oxygen consumption by the whole brain attains 46 ml/min. This makes up approximately 20% of the total oxygen volume consumed by the organism. Consequently, the cerebral tissue is characterised by highly energetic processes. There is evidence indicating that even in functionally resting conditions, 18% of the entire energy expenditure of the body is utilised by the brain Calculations made by Rushmer indicate that the intensity of energy consumption by the human brain appears to be on average 20 Watt.

Easily understood, up-to-date and clinically relevant, this book provides junior anaesthetists with an essential physiology resource.

This second edition presents core clinical neuroanesthesia and neurointensive care knowledge in a practical, user-friendly format.

While there are a number of books on the market that deal with neuronal mechanisms and targets, the proposed book will be the only one to cover the vascular aspects of CNS trauma. The contributing authors will present basic mechanisms, explain cutting-edge experimental models and techniques, and provide several clinical chapters that provide treating physicians with some insight on the cases that they see in the ICU. The table of contents is diverse and comprehensive with chapters on molecular mechanisms, physiology, pharmacology, stem cells, genomics and proteomics, in vivo MRI and PET, as well as the clinical management of vascular parameters.​

Until recently, monitoring of cerebral blood flow and metabolism was an unattained goal. Determination of cerebral blood flow was limited to intermittent measurements and particularly difficult to perform in critically ill patients. Meanwhile there are techniques available, however, to monitor cerebral blood flow and cerebral oxygenation, both globally and regionally. Therefore we thought it worthwhile to discuss these new continuous techniques and to compare them with well-known techniques which discontinuously measure CBF. For that purpose, an international workshop with some leading experts in the field was held in October 1992 in Berlin. The workshop consisted of about 20 lectures, either reviews on a special topic, or latest results. These contributions were given by invitation and were extensively discussed. Unfortunately it is impossible to reproduce the discussions. On the other hand, all speakers delivered a manuscript promptly after the meeting so that we were able to edit them within a short time. Since monitoring of cerebral blood flow in intensive care is a rapidly growing and changing topic, the written contributions should be quickly available. Authors, editors and publishers have tried to come close to this ideal. As editors we would like to thank the authors and the publishers who enabled us to come out with this volume of the proceedings as early as possible.

Every few years a dissertation comes to the area of clinical application of medical technology which carries us forward as on a magic carpet into new regions of understanding and patient care. This book is such a magic carpet. It brings together, in a clear and incisive fashion, important hemodynamic principles with a simple noninvasive method of application to a part of the cerebral vasculature which has been relatively inaccessible. To the lucky and perceptive person who reads this book, a feeling of excitement and hope for progress is engendered. The diligent application of the potentials of transcranial Doppler ultrasound brings new power to our efforts in understanding the cerebral circulation and the causes, treatment and prevention of cerebrovascular disorders. Merrill P. Spencer, M. D. Director Institute of Applied Physiology and Medicine Seattle, Wash. , July 1986 Acknowledgements I am greatly indebted to Prof. He1ge Nornes, Oslo, who introduced me to the fascinating study of cerebral hemodynamics in the early 1970's and since then continually encouraged my interest in this field. It was through his pioneering work on the cerebral circulation-using peroperative electromagnetic flowmetry and Doppler techniques-that the basis was laid for the noninvasive trans cranial approach to the circle of Willis described in this book. I also gratefully acknowledge the stimulating case discussions with Prof. Peter Huber, Berne, at the very early introduction of trans cranial Doppler, the inspiring exchange of ideas with Dr. Merrill P.

Cardiovascular disease remains a major cause of death and disability in developed countries and, increasingly so, in the developing world. Presented in this volume of Advances in Pharmacology are some of the most promising possibilities for treating large numbers of individuals afflicted with these conditions. - Contains up-to-date reviews of the most important emerging cardiovascular therapies written by world leaders in the field

Brain dysfunction is a major clinical problem in intensive care, with potentially debilitating long-term consequences for post-ICU patients of any age. The resulting extended length of stay in the ICU and post-discharge cognitive dysfunction are now recognized as major healthcare burdens. This comprehensive clinical text provides intensivists and neurologists with a practical review of the pathophysiology of brain dysfunction and a thorough account of the diagnostic and therapeutic options available. Initial sections review the epidemiology, outcomes, relevant behavioral neurology and biological mechanisms of brain dysfunction. Subsequent sections evaluate the available diagnostic options and preventative and therapeutic interventions, with a final section on clinical encephalopathy syndromes encountered in the ICU. Each chapter is rich in illustrations, with an executive summary and a helpful glossary of terms. Brain Disorders in Critical Illness is a seminal reference for all physicians and neuroscientists interested in the care and outcome of severely ill patients.