In the preface to the text that preceded this edition, we predicted that the pace of change in the clinical practice of pediatric surgery, and in our understanding of the scientific principles that are the basis for that practice, would soon render the text obsolete. That expectation was more predictable than prescient, and it has clearly come to pass. During the intervening years, important basic science advances in pharmacology, immunology, genetics, embryology, developmental biology, and other relevant areas were reported almost daily. Virtually every knowledgeable physician and scientist anticipates that this process will continue, perhaps accelerating further. The trend is similar in clinical practice. Although the rate of real change is arguably slower, it is undoubtedly substantial. Minimally invasive surgical techniques or their derivatives are now employed for many, perhaps most, major intracavitary procedures in infants and children. Now routine are minimally invasive complex procedures such as laparoscopic pullthrough for imperforate anus and Hirschsprung's disease, among others, while repair of tracheoesophageal fistula, portoenterostomy for biliary atresia, and other procedures requiring a high level of surgical precision are more and more feasible. Robotic technology is now in place in a number of major children's centers around the world, and this too will be an engine for change.
Since the original version of this text was published in 1997, serious effort has been invested in the development of rigorous clinical research tools to improve medical and surgical practice and to quantify outcomes. Evidence-based decision making and demonstrable quality are now demanded from the public, payors, and other health care providers in a way not imagined even a few years ago. Emerging problems require new surgical approaches. For example, the field of bariatric surgery as it relates to children and adolescents has developed of necessity in the last several years, driven by a stunning worldwide obesity epidemic and a host of attendant comorbidities now affecting the young. Each of these individual areas, and many others, receive explicit and detailed new attention in this text, either in the form of entirely new or substantially revised chapters.