Neuromonitoring Techniques

Abstract

The ability to monitor brain function during neurosurgery and in the neurointensive care unit has advanced dramatically during recent years, and a wide range of neuromonitoring techniques have become incorporated into routine clinical practice. However, the complex science underlying these tools and their clinical interpretation can be challenging for both novice and experienced clinicians. Fortunately, this textbook, edited by an expert in the field—Hemanshu Prabhakar, professor of neuroanaesthesia in New Delhi, India, and an executive editor of the Journal of Neuroanaesthesiology and Critical Care, has been written to help. Neuromonitoring Techniques consists of 11 chapters that cover the key methods of neurological and cognitive monitoring or analysis. The chapters include the traditional methods of intracranial pressure, cerebral blood flow, and jugular venous oximetry monitoring; electroencephalography and evoked response monitoring; and brain microdialysis and the expanding fields of brain tissue oxygenation, cognitive function monitoring, and functional magnetic resonance imaging. Each chapter begins with a detailed content list and an introduction that puts the monitoring modality in context. There is then a more detailed explanation of the basic physiological principles behind the modality and descriptions of its clinical use. Technical explanations are well supported with relevant equations, color pictures, and diagrams that break up the text and reinforce understanding. For residents learning about monitoring techniques for the first time, the illustrations are a highlight of the book. An effort has also been made to include descriptions and pictures of a range of brands for each device. The chapters then conclude with a summary of expert consensus opinion on the role of each technique in contemporary clinical practice and suggestions for more in-depth reading. As anesthesiologists, we found the section titled “Effects of Anesthetics” of particular interest. Another highlight was the foreword written by Dr Elizabeth Frost, detailing her neuroanesthesia residency in the 1960s. She describes working with a neurosurgeon who insisted on the use of ether along with cautery, necessitating the anesthesia team to drape the machine, and themselves, in wet towels in case of fire. In addition to the strengths of this text, there are limitations. This book requires more thorough editing. Errors in both grammar and spelling appear with reasonable regularity. There are graphs that do not have numbers on their axes, and there are errors in factual content. The most concerning is on page 35, where the authors state: “Paco2 has a powerful vasoconstrictor effect on brain vessels” … “for each kPa increase of CO2 in arterial blood, there is a reduction of 15 mL/100 g/min in CBF.” This is the opposite of the true relationship, and could lead to undesirable clinical effects for the unsuspecting trainee. This error requires an addendum to correct it. Although the literature is well summarized, it was not always clear when or why one technique should be chosen over another. Clinicians new to this field may find it challenging to decide which method should be used and in which clinical context because the techniques discussed in each chapter seem to be advocated by the authors. The book could also have been improved by the inclusion of clinical case studies or examples that illustrate the value of the monitors. In summary, Neuromonitoring Techniques is a concise, well-illustrated, and comprehensive introductory text on neuromonitoring techniques for clinicians specializing in neurosurgery, neurophysiology, neuroanesthesia, and neurointensive care. The paperback is lightweight and easily portable. The eBook is also a good option, with enhanced, readable typesetting, highlighting, note-taking, and search functions to support the learning process. The book will be of use to both senior trainees preparing for subspecialty examinations and experienced clinicians wishing to keep up to date. It is a worthwhile addition to departmental libraries, but future editions will require more careful editing. Doug Campbell, BM, FRCA, FANZCAStephanie Clark, MBChBDepartment of Anaesthesia and Perioperative MedicineAuckland City HospitalAuckland, New Zealand Timothy G. Short, MBChB, MD, FANZCADepartment of Anaesthesia and Perioperative MedicineAuckland City HospitalAuckland, New ZealandDepartment of AnaesthesiaFaculty of Medical and Health SciencesUniversity of AucklandAuckland, New Zealand