Preface

From the healthcare provider perspective, the word "shock" is associated with a mixed array of feelings, including dread, well-founded fear, and deep respect. The physiological state of shock is well recognized for the associated destructive consequences, and its successful management requires prompt identification, immediate action, and sustained effort by all members of the healthcare team [1–4]. Taking after the notion of "sudden violent blow or impact [5]," the physiological state of shock is conceptually similar to the human "fear response" in face of the unexpected of unknown. Putting it all together with the relevant clinical construct of shock, as eloquently stated by Mary Renault, "There is only one kind of shock worse than the totally unexpected: the expected for which one has refused to prepare [6]." This mindset of advanced preparation and constant readiness constitutes the foundation of the modern approach toward shock – early detection and prompt treatment for optimal outcomes.

Despite the heterogeneity of "shock" as a clinico-pathological entity, there are some common threads that permeate all forms and manifestations of shock, with apparent increase in observed commonalities in the more advanced (and often irreversible) stages of the systemic syndrome. Whether hemorrhagic, septic, or anaphylactic, the state of shock is felt similarly at the tissue level – there is an acute decrease in vital supplies to tissues, resulting in system-wide cellular distress. The body and its systems do their best to compensate for the maldistribution of oxygen and nutrients, up to a certain point [7–9]. This is commonly recognized as so-called compensated shock. Beyond that, the body loses its ability to adjust any further, thus descending into a state of "uncompensated shock," with a refractory state characterized by vasoplegia and irreversible cardiovascular failure [10, 11].

As the reader journeys through the chapters of the book, he or she will read about various biomarkers and endpoints of resuscitation, explore different types of shock (e.g., septic, hemorrhagic, anaphylactic), and learn about some of the less often discussed topics such as neurogenic and spinal shock as well as amniotic fluid embolism. Although not specifically discussed as a focus of a dedicated chapter, cardiogenic shock and cardiac dysfunction will be discussed throughout this collective work, especially as it relates to the various stages and manifestations of different shock states. Our other goals were to keep things clinically relevant and practically oriented, thus enabling the reader to apply the newly acquired knowledge in their everyday clinical routines.

This book is a collection of unique chapters, each dedicated to a different area within the expansive and heterogeneous subject of shock. As the reader progresses through the book, we hope to help stimulate further discourse and innovative thinking about the topic. We also hope to shed light on various other dimensions of a clinical problem that all too often becomes reduced to protocolized management approaches without much reflection on its true mechanistic and energetic implications and impact. While the authors hope that this textbook will enlighten healthcare providers as to diagnosis and treatment of shock, it must be acknowledged that the currently available guidelines regarding the treatment of this malady do not provide

guidance on post-hospital care or recovery [12–14]. In the latter context, an entire unexplored area of long-term complications of critical care awaits much needed research [15, 16]. It is also critical that basic, translational and clinical research on shock is sufficiently balanced between different types of shock to improve our understanding of all pertinent pathophysiologic states, whether due to infection, amniotic fluid emboli, myocardial infarction, or neurological injury. In this way, scientific progress will help improve outcomes for patients with both rare and common forms of shock.
