Book Review

Understanding Acid-Base

N Engl J Med 1998; 339:1170-1171October 15, 1998

Article

Understanding Acid-Base
By Benjamin Abelow. 333 pp., illustrated. Baltimore, Williams & Wilkins, 1998. $24.95. ISBN: 0-683-18272-2

For most students of medicine, acid–base homeostasis (and its disorders) remains an elusive and arcane subject. This is not surprising: the concepts underlying the clinical management of acid–base homeostasis are complex, involving chemistry as well as physiology, and textbooks on the subject often fail to communicate these concepts clearly. Understanding Acid-Base is a remarkably successful attempt to cut through this complexity and to present the subject unambiguously. The approach is unique because the author is not an expert in the field but came to the subject as a student himself, trying to gain a full understanding of the topic. His single-minded pursuit of this goal resulted in this textbook.

Abelow's energy has been well directed. He has managed to present this complex subject in a very readable and disarmingly straightforward style. Considerable effort clearly underlies the simplicity of this style. All the aspects of the book have been given meticulous attention, from the instructive approach to the structure and content of each chapter. The book is organized into five distinct sections: chemistry, physiology, pathophysiology, diagnosis, and treatment. As the author indicates in the introduction, each is self-contained so that readers can pick a section of interest to read as a “stand alone,” depending on their level of knowledge of the subject. The book is so readable, however, that readers can quickly move from one section to the next to get more information.

The first section is preceded by a brief review of the fundamentals, including the definitions of “ion,” “mole,” and “equivalent.” This chapter sets the stage: throughout the book, there is no ambiguity, and there is nothing that is not explained completely. Each section ends with a comprehensive self-assessment quiz, with answers provided, in classic textbook fashion. Although the book focuses on the information necessary to understand and manage acid–base disorders, a valuable feature is the appendix, which covers specific areas in more depth. Readers can peruse these areas or not, depending on their level of interest. The appendix is brief and readable as well. At the end of the book, the author encourages readers to seek out other sources to gain deeper knowledge of the subject, and he gives an extensive annotated list of suggested publications that reflect various approaches to the topic.

The author's superb ability as a textbook writer is partially counterbalanced by the lack of depth of his knowledge of the field. The substance of the book appears to have been provided largely by Drs. Aronson, Wright, and Rastegar, all experienced acid–base physiologists and clinicians, and particularly by Dr. Rastegar, whose conversations the author recorded to make sure he would get the information right. The author's lack of depth is most apparent in the sections on pathophysiology and treatment. For example, to sum up the complex and controversial issues regarding the pathophysiology of metabolic alkalosis, he uses the acronym “HAV” (hypokalemia, aldosterone, volume) — “it's all you HAV to remember.” This is a handy device for beginning students who are hungry for a simple answer, but unfortunately they HAV to remember a lot more if they really want to understand the pathophysiology of this disorder. The author is also overly simplistic about the effect of bicarbonate administration on extracellular potassium concentration. The evidence is far from clear that it causes a rapid shift of potassium into cells. He seems to be unaware that hypocapnia during hemodialysis occurs only when the bath solution contains no bicarbonate — a rare event in 1998. These, however, are minor shortcomings. The book is at its best when it covers the basics and topics such as venous electrolytes and arterial-blood gases.

The clarity, instructive style, and readability of Understanding Acid-Base make it one of the best in the field both for beginning students and for those who want to refresh their basic knowledge in the area. I encourage the author, who has a real talent for textbook writing, to interview experts in other fields and publish additional books for teaching. Despite his assertion that acid–base homeostasis is “one of the most important” areas of medicine, many other very important areas could benefit from his superb writing skills.

F. John Gennari, M.D.
University of Vermont College of Medicine, Burlington, VT 05405