Pre-Operative Fasting, vol. 20, no. 3 in Best Practice & Research, Clinical Anaesthesiology, September 2006
Ljungqvist O, Soreide E, eds. Amsterdam: Elsevier, 2006. ISSN 1521-6896. 131 pages, $196.00 for four issues or $71.02 for a single issue.
This issue of Best Practice & Research: Clinical Anaesthesiology is intended to provide an evidence-based review of current clinical practice in regards to preoperative fasting. In the years since the practice of fasting from midnight before surgery was accepted, many new aspects regarding preoperative fasting, including the metabolic effects of fasting and several new guidelines, have arisen.
The book consists of 9 chapters, each chapter written by different authors (a total of 19 authors from 6 different countries). As with any effort that spans many countries, the editorial effort to maintain uniformity while reading the various chapters is important. The author selection, consisting mostly of anesthesiologists with a few gastroenterologists and surgeons, seems appropriate. Each chapter begins with a succinct review of the entire chapter and ends with bulleted practice points. The last chapter summarizes the information provided in the previous chapters and provides a quick review for the reader.
Chapter 1 provides the historical background and the real basis of the currently accepted standard clinical practice of preoperative fasting by the patient from the midnight before surgery. Chapter 2 elaborates on the barriers to the acceptance and incorporation of new ideas, especially when presented as guidelines, into clinical practice. Understanding this phenomenon is essential to identifying the factors responsible for resistance to change. This chapter is very well written and introduces the subject of change management. Readers can use some of the suggested methods and techniques when introducing changes into other areas of their clinical practice. Chapter 3, which describes the process of gastric emptying, may contain information that is new to some anesthesiologists, but this reviewer found the chapter rather dry and hard to read.
In Chapter 4, the practical management of the dreaded complication of pulmonary aspiration of gastric contents is described using concepts based on crisis management and is summarized as an algorithm. In reviewing the pathophysiology of aspiration, a distinction is made between aspiration pneumonitis and aspiration pneumonia.
Chapter 5 discusses the metabolic changes that occur during fasting, in relation to surgical stress. Anyone interested in preventing perioperative hyperglycemia should find this chapter very useful. Chapter 6 elaborates on perioperative fluid management and its impact on postoperative outcome. The authors make a fine point that if patients arrive at the operating room in a state of normal electrolyte and fluid balance, then there is less need to resuscitate them. Anesthesiologists practicing perioperative medicine should be quite familiar with this topic and may find some of this information repetitive. In Chapter 7, current evidence behind fasting guidelines, gleaned from a Cochrane report, is summarized. The author cautions the reader to evaluate the evidence themselves and to modify the existing fasting guidelines when necessary on an individual basis. Although this is a noble pursuit, in the current atmosphere of following rigid hospital policies and performing several “time-outs” in the operating room, this may not be practical in those hospitals where the schedule is constantly changing. Chapter 8 provides fasting guidelines for various types of food in normal infants and children (i.e., those without gastrointestinal disorders). While the authors acknowledge that residual gastric volume is used as a surrogate marker for pulmonary aspiration, they are guilty of introducing yet another acronym “GFV” (gastric fluid volume) in their text. Chapter 9, authored by the editors, is a summary of the previous chapters, presents the current recommendations, and identifies the need for more research to define best practice.
The authors must be commended for identifying the lacunae in the existing medical literature and presenting key ideas as topics for possible research at the end of each chapter. While much data is presented in tables, the entire book has a lone figure that demonstrates the proper application of cricoid pressure. This issue is in paperback format, with 131 pages. The pages are of good quality and the book is a handy size; however, the font is rather small.
From a patient’s perspective, preoperative fasting is one of the rather unpleasant routines before surgery. This well-written review, with clear recommendations, comes at a time when clinicians consider patient satisfaction as an important outcome.
In summary, the editors have succeeded in their objective of providing an update for clinicians and trainees through this well-balanced review that offers information on every aspect of preoperative fasting. By providing some insight and guidance, this book should be a useful resource to clinical anesthesiologists interested in rewriting their hospital policies using guidelines issues by various societies to more modern standards.
Srikantha L. Rao, MB, BS
Assistant Professor of Anesthesiology
Penn State College of Medicine
Milton S. Hershey Medical Center