Centra Communications, 2015. — 32 p.
Understanding the chemistry of water and hydrogen ions is an important part of understanding the living system because hydrogen ions participate in so many reactions. One interesting facet of human homeostasis is the tight control of hydrogen ion concentration, [H+]. As metabolism creates about 300 liters of carbon dioxide each day, and as we also consume about several hundred mEq of strong acids and bases in the same period, it is remarkable that the biochemical and feedback mechanism can maintain [H+] between 30 and 150 nanoEq/liter
Appreciation of the physics and chemistry involved in the regulatory process is essential for all life scientists, especially physiologists. Many physiology textbooks start the discussion of acid-base equilibrium by defining pH , which immediately followed by the Henderson-Hasselbalch equation
Attention has recently shifted to a quantitative physicochemical approach to acid- base physiology. Many of the generally accepted concepts of hydrogen ion behaviour are viewed differently. This analysis, introduced by Peter Stewart in 1978, provides a chemical insight into the complex chemical equilibrium system known as acid-base balance
The impact of Stewart’s analysis has been slow, but there has been a recent resurgence in interest, particularly as this approach provides explanations for several areas which are otherwise difficult to understand (e.g. dilutional acidosis, acid-base disorders related to changes in plasma albumin concentration)
Undoubtedly, the physicochemical approach will become more important in the future and this brief review provides an introduction to this method
Yohanes WH George, MD Anesthesiology Intensivist Head of Emergency & Intensive Care Unit, Pondok Indah Hospital – Jakarta Indonesia Lecturer, Department of Anesthesiology and Intensive Therapy – Faculty of Medicine, University of Indonesia
Dedication
Foreword
Stewart’s Approach in Brief
Strong Ion Difference
Classification of Primary Acid Base Disturbances
The Effect of Saline and Balanced Fluid from Stewart’s Perspective
Designing Balanced Crystalloids
Body pH Regulation: Interaction Between Membranes
Strong Ion Difference in Kidney
Compensation
Clinical application
Conclusions