Of all tests performed on patient blood samples, arterial blood gases (ABGs) are conceptually probably the most complex. An understanding of the clinical significance of the measured and derived parameters generated by blood gas machines depends on a basic knowledge of so many topics, including acid-base theory, blood buffers, respiratory and renal physiology, hemoglobin and its role in transport of gases and so on. Moreover, it is important to appreciate the interrelatedness of these topics. Not surprising then that health professionals often find the interpretation of patient blood gas results daunting at first, and that books like this are necessary and welcome.

 

This is an introductory course or "workbook" on blood gas analysis with written exercises to be completed by the reader at each stage of learning. The first of five chapters is an introduction to the measured parameters and allows familiarization with the symbols, units and reference ranges. There are explanations of the concept of acidity/alkalinity, partial pressure of a gas, bicarbonate, base excess and oxygen saturation. The second chapter deals with blood transport of oxygen and carbon dioxide and includes a brief discussion of the oxygen dissociation curve. The third chapter deals with the physiology of acid-base balance, introduces the concept of buffers and highlights the role of lungs and kidneys in maintaining blood pH. The fourth chapter is devoted to the interpretation of blood gas results and explains the four classes of acid-base disturbance and the concept of compensation. Algorithms to aid interpretation of blood gas results are included and 15 sets of blood gas results are presented for interpretation by the reader. The final chapter is devoted to collection of arterial blood.

 

When preparing a book like this for the novice, it must be difficult to decide what is most relevant and necessary for inclusion and what to exclude. Overall I think the author has chosen the right topics to discuss, but the depth of discussion is perhaps a little too superficial. Although I like the idea of a "workbook" and the opportunity for readers to assess their understanding, the ratio of worksheets to information seems too high. The book serves as a gentle first introduction to the topic of arterial blood gases.