Cerebral Oxygenation In Health And Disease

Scientists and clinicians interested in cerebrovascular physiology in humans now have numerous possibilities to monitor, invasively or non-invasively, the oxygenation status of cerebral tissue. Monitoring cerebral oxygenation has several utilities; to improve patient outcome, to better understand the mechanisms underlying orthostatic hypotension; to provide insight into functional neurovascular coupling; to evaluate the influence of vasopressors on cerebral oxygen levels in patients under anesthesia; and to study the limitations of exercise tolerance. This themed research topic, through theoretical and experimental papers, covers new and exciting issues related to the study of cerebral oxygenation in health and disease. This e-book includes manuscripts inclusive of original research, methodologies and reviews in the field of integrative physiology, cognitive testing, orthostatic stress, exercise physiology and anesthesia.

The Oxford Textbook of Neurocritical Care provides an authoritative and up-to-date summary of the scientific basis, clinical techniques and management guidelines in this exciting clinical discipline. Authored by an international team of expert practitioners this textbook reflects world-wide practice.

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.

This book presents cutting-edge papers and perspectives on the transport of oxygen to tissues by scientists in a multitude of disciplines such as biochemistry, engineering, mathematics, medicine, physics, physiology, veterinary and complementary medicine. The book is composed of the following 6 parts: Brain Oxygenation and Function, Tumor Oxygenation and Metabolism, Muscle Oxygenation and Sports Medicine, Cell Metabolism and Tissue Oxygenation, Methodology of O2 Measurements, and Special Topics. The articles in this book have been presented at the 46th annual meeting of the International Society on Oxygen Transport to Tissue (ISOTT 2018) held in Seoul, Republic of Korea, from July 1 to July 5, 2018. Academics, clinical and industry researchers, engineers, as well as graduate students who are interested in oxygen transport to tissue will find this book a great reference and a useful learning resource.

Core Topics in Neuroanesthesia and Neurointensive Care is an authoritative and practical clinical text that offers clear diagnostic and management guidance for a wide range of neuroanesthesia and neurocritical care problems. With coverage of every aspect of the discipline by outstanding world experts, this should be the first book to which practitioners turn for easily accessible and definitive advice. Initial sections cover relevant anatomy, physiology and pharmacology, intraoperative and critical care monitoring and neuroimaging. These are followed by detailed sections covering all aspects of neuroanesthesia and neurointensive care in both adult and pediatric patients. The final chapter discusses ethical and legal issues. Each chapter delivers a state-of-the art review of clinical practice, including outcome data when available. Enhanced throughout with numerous clinical photographs and line drawings, this practical and accessible text is key reading for trainee and consultant anesthetists and critical care specialists.

This presentation describes various aspects of the regulation of tissue oxygenation, including the roles of the circulatory system, respiratory system, and blood, the carrier of oxygen within these components of the cardiorespiratory system. The respiratory system takes oxygen from the atmosphere and transports it by diffusion from the air in the alveoli to the blood flowing through the pulmonary capillaries. The cardiovascular system then moves the oxygenated blood from the heart to the microcirculation of the various organs by convection, where oxygen is released from hemoglobin in the red blood cells and moves to the parenchymal cells of each tissue by diffusion. Oxygen that has diffused into cells is then utilized in the mitochondria to produce adenosine triphosphate (ATP), the energy currency of all cells. The mitochondria are able to produce ATP until the oxygen tension or PO2 on the cell surface falls to a critical level of about 4–5 mm Hg. Thus, in order to meet the energetic needs of cells, it is important to maintain a continuous supply of oxygen to the mitochondria at or above the critical PO2 . In order to accomplish this desired outcome, the cardiorespiratory system, including the blood, must be capable of regulation to ensure survival of all tissues under a wide range of circumstances. The purpose of this presentation is to provide basic information about the operation and regulation of the cardiovascular and respiratory systems, as well as the properties of the blood and parenchymal cells, so that a fundamental understanding of the regulation of tissue oxygenation is achieved.

Close monitoring of patients during anesthesia is crucial for ensuring positive treatment outcomes and patient safety. The increasing availability of new technologies and the repurposing of older monitors means more patient data is at anesthesiologists' fingertips than ever before. However, this flood of options can be overwhelming. A practical resource for understanding this array of clinical monitoring options in anesthesia, this important text focuses on real-world applications in anesthesia and perioperative care. Reviewing the evidence for improved patient outcomes for monitoring technology, neurological monitoring, echocardiography systems and ultrasound are amongst the techniques covered in a head-to-toe approach. Statistics used by manufacturers to gain approval for their technology are discussed, as well as the under-appreciated risks associated with monitoring such as digital distraction. Future monitoring technologies including wearable systems are explored in depth. Focusing on applied practice, this book is an essential text for front-line healthcare professionals in anesthesia.