Porth's Essentials of Pathophysiology, 4e

2 U N I T Composition and Compartmental Distribution of Body Fluids Movement of Body Fluids Between Compartments Dissociation of Electrolytes Osmosis and Tonicity Compartmental Distribution of Body Fluids Capillary/Interstitial Fluid Exchange Edema Third-Space Accumulation Water and Sodium Balance Regulation of Water Balance Regulation of Sodium Balance Mechanisms of Water and Sodium Regulation Thirst and Disorders of Thirst Antidiuretic Hormone and Disorders of Antidiuretic Hormone Disorders of Water and Sodium Balance

Integrative Body Functions

luids and electrolytes are present in body cells, in the tissue spaces between the cells, and in the blood that fills the vascular compartment. Body fluids transport gases, nutrients, and wastes; help generate the electri- cal activity needed to power body functions; take part in the transforming of food into energy; and otherwise maintain the overall function of the body. Although fluid volume and composition remain relatively constant in the presence of a wide range of changes in intake and output, conditions such as environmental stresses and disease can impair intake, increase losses, and otherwise interfere with mechanisms that regulate their volume, composition, and distribution. This chapter is divided into five sections: composition and compartmental distribution of body fluids; disor- ders of sodium and water balance; disorders of potas- sium balance; disorders of calcium, phosphorus, and magnesium balance; and disorders of acid–base balance. 8 C h a p t e r Disorders of Fluid, Electrolyte, and Acid–Base Balance Composition and Compartmental Distribution of Body Fluids Body fluids are distributed between the intracellular and extracellular fluid compartments. 1–3 The intracel- lular fluid (ICF) compartment¸ which consists of the F

Isotonic Fluid Volume Deficit Isotonic Fluid Volume Excess

Hyponatremia Hypernatremia

Potassium Balance Regulation of Potassium Balance Disorders of Potassium Balance

Hypokalemia Hyperkalemia Calcium, Phosphorus, and Magnesium Balance Disorders of Calcium Balance Regulation of Calcium Balance

Hypocalcemia Hypercalcemia Disorders of Phosphorus Balance Regulation of Phosphorus Balance Hypophosphatemia Hyperphosphatemia Disorders of Magnesium Balance Regulation of Magnesium Balance Hypomagnesemia Hypermagnesemia Disorders of Parathyroid Hormone

Hypoparathyroidism Hyperparathyroidism

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