Introduction

Knowledge and error flow from the same mental sources, only success can tell the one from the other.

Ernst Mach, 1905

There are many veterinary anesthesia texts on how to anesthetize a variety of animal patients; such is not the purpose of this text. It does, however, have everything to do with the processes involved in anesthetizing animal patients, from pre-anesthetic assessment to recovery, and does so by seeking answers to how and why errors occur during anesthesia. In this text we define an error as a failure to carry out a planned action as intended (error of execution), or the use of an incorrect or inappropriate plan (error of planning), while an adverse incident is a situation where harm has occurred to a patient or a healthcare provider as a result of some action or event. How can those who are responsible for the anesthetic management of patients detect and manage unexpected errors and accidents during anesthesia? How can we learn from errors and accidents?

In the heat of the moment when a patient under our care suffers a life-threatening injury or dies, it is natural to look for something or someone to blame; usually the person who "made the mistake." This is a normal response. Subsequently we may reprimand and chastise the individual who caused the accident and, by so doing, assume we've identified the source of the problem and prevented it from ever occurring again. Unfortunately, such is not the case because this approach fails to take into account two realities: (1) all humans, without exception, make errors (Allnutt 1987); and (2) errors are often due to latent conditions within the organization, conditions that set the stage for the error or accident and that were present long before the person who erred was hired. We can either acknowledge these realities and take steps to learn from errors and accidents, or we can deny them, for whatever reasons, be they fear of criticism or litigation, and condemn ourselves to make the same or similar errors over and over again (Adams 2005; Allnutt 1987; Edmondson 2004; Leape 1994, 2002; Reason 2000, 2004; Woods 2005).

In general there are two approaches to studying and solving the problem of human fallibility and the making of errors: the person approach (also called proximate cause analysis) and the systems approach (Reason 2000). The person approach focuses on individuals and their errors, and blames them for forgetfulness, inattention, or moral weakness. This approach sees errors arising primarily from aberrant mental processes, such as forgetfulness, inattention, poor motivation, carelessness, negligence, and recklessness (Reason 2000). Those who follow this approach may use countermeasures such as poster campaigns that appeal to people's sense of fear, develop new procedures or add to existing ones, discipline the individual who made the error, threaten litigation, or name, blame, and shame the individual who erred (Reason 2000). It's an approach that tends to treat errors as moral issues because it assumes bad things happen to bad people-what psychologists call the "just world hypothesis" (Reason 2000).

In contrast, the systems approach recognizes the fundamental reality that humans always have and always will make errors, a reality we cannot change. But we can change the conditions under which people work so as to build defenses within the system, defenses designed to avert errors or mitigate their effects (Diller et al. 2014; Reason 2000; Russ et al. 2013). Proponents of the systems approach strive for a comprehensive error management program that considers the multitude of factors that lead to errors, including organizational, environmental, technological, and other system factors.

Some, however, have misgivings about these two approaches as means of preventing errors in medical practice. A prevalent view is that clinicians are personally responsible for ensuring the safe care of their patients and a systems or human factors analysis approach will lead clinicians to behave irresponsibly, that is, they will blame errors on the system and not take personal responsibility for their errors (Leape 2001). Dr Lucian Leape, an advocate of the systems approach, points out that these thoughts only perpetuate the culture of blame that permeates healthcare (Leape 2001). The essence of systems theory is that human errors are caused by system failures that can be prevented by redesigning work environments so that it is difficult or impossible to make errors that harm patients (Leape 2001). Leape contends that this approach does not lessen a clinician's responsibility, but deepens and broadens it; when an error does occur the clinician has a responsibility-an obligation-to future patients to ask how the error could have been prevented, thus questioning the system with all of its component parts. Leape goes on to say that fears about "blameless" medicine are unfounded and are related to the universal tendency to confuse the making of an error with misconduct (Leape 2001). Misconduct, the willful intent to mislead or cause harm, is never to be tolerated in healthcare. Multiple studies in many different types of environments including healthcare, have shown that the majority of errors-95% or more-are made by well-trained, well-meaning, conscientious people who are trying to do their job well, but who are caught in faulty systems that set them up to make mistakes and who become "second victims" (Leape 2001). People do not go to work with the intent of making errors or causing harm.

This text is written with a bias toward the systems approach, a bias that has grown out of our experiences as anesthetists, as teachers of anesthesia to veterinary students, residents, and technicians, and as individuals who believe in the principles and practices underlying continuous quality improvement. This latter stance is not unique and reflects a movement toward the systems approach in the larger world of healthcare (Chang et al. 2005).

No part of this book is written as a criticism of others. Far from it. Many of the errors described herein are our own or those for which we feel fully responsible. Our desire is to understand how and why we make errors in anesthesia so as to discover how they can be prevented, or more quickly recognized and managed. We believe that the systems approach allows us to do just that. It is also an approach that can be used to help teach the principles of good anesthetic management to those involved in veterinary anesthesia. This approach also has broader applicability to the larger world of veterinary medicine.

This text consists of eight chapters. The first chapter is divided into two sections, the first of which briefly discusses terminology and the use of terms within the domain of patient safety. The reader is strongly encouraged to read the brief section on terminology because it defines the terms we use throughout this book. Terms, in and of themselves, do not explain why or how errors occur; that is the purpose of the second section, which provides some answers to the "whys" and "hows" of error genesis. This discussion draws upon a large body of literature representing the results of studies into the causes and management of errors and accidents; a body of literature spanning the fields of psychology, human systems engineering, medicine, and the aviation, nuclear, and petrochemical industries. This section is not an exhaustive review of the literature, but is meant to acquaint the reader with error concepts and terminology that are the basis for understanding why and how errors happen.

Terminology, especially abbreviations, can be a source of error. In the medical literature many terms are abbreviated under the assumption they are so common that their meanings are fully recognized and understood by all readers. For example, ECG is the abbreviation for electrocardiogram unless, of course, you are accustomed to EKG, which derives from the German term. It is assumed that every reader know that "bpm" signifies "beats per minute" for heart rate. But wait a minute! Could that abbreviation be used for breaths per minute? Or, what about blood pressure monitoring? And therein is the problem. A number of studies have clearly shown that abbreviations, although their use is well intentioned and meant to reduce verbiage, can be confusing, and out of that confusion misunderstandings and errors arise (Brunetti 2007; Kilshaw et al. 2010; Parvaiz et al. 2008; Sinha et al. 2011). This reality has led us to avoid using abbreviations as much as possible throughout the book. In the few instances where we do use abbreviations, primarily in the chapters describing cases and near misses, we spell the terms in full and include in parentheses the abbreviations that will be used in that particular case or near miss vignette. It seems like such a minor detail in the realm of error prevention, but the devil is in the details.

The second chapter presents the multiple factors that cause errors, including organizational, supervisory, environmental, personnel, and individual factors. At the organizational level the discussion focuses on organizational features that are the hallmarks of "learning organizations" or "high reliability organizations," organizations with a culture attuned to error prevention and a willingness and ability to learn from errors. Because individuals are at the forefront-at the sharp end-of systems where errors occur this chapter discusses cognitive factors that can lead to error generation.

The third...