Chapter 17 - Fluid, Electrolyte, and Acid-Base Balance

Abstract

This chapter discusses the physiology of fluid, electrolyte, and acid-base balance. The body fluids are arranged in dynamic, but orderly, functional compartments. Maintenance of these compartments in terms of volume and composition is essential for sustaining normal physiological and biochemical events. The electrolytes dissolved in body fluids fulfill vital roles in virtually all of life's processes. Transmembrane movements of electrolytes are responsible for the electrical events that result in nerve conduction and muscular contraction. The electrical stability of membranes is highly dependent on the concentration of electrolytes on both sides. Electrolytes also serve as essential cofactors in many enzymatically mediated metabolic reactions. The pH of body fluids is maintained within narrow limits. This fine control is necessary to maintain the structure and function of proteins essential for normal progression of metabolic events. Virtually every organ system participates in the maintenance of fluid and electrolyte balance, or is adversely affected by imbalances. This chapter discusses in detail the body fluid compartments. Regulation of body fluids and electrolytes is also discussed. The chapter elaborates the clinical features of fluid and electrolyte balance. Clinicopathological indicators of fluid and electrolyte imbalance are also discussed.