Fluid /Electrolyte Balance  Elmhurst College Fluid Exchange Processes Fluid Exchange kidneys Fluid Deficit  Chemistry Department Fluid Exchange in Tissues Fluid Excess    Virtual ChemBook

Compartments of Body and Distribution of Water by Weight Plasma 5% Interstitial 15% Intracellular 40% Total 60 % Water Solids - 40% fat, protein, carbohydrates, minerals

Fluid and Electrolyte Balance The main fluid in the body is water. Total body water is 60% of body weight. The water is distributed in three main compartments separated from each other by cell membranes. The intracellular compartment is the area within the cell. The extracellular compartment consists of the interstitial area (between and around cells) and the inside of the blood vessels (plasma).

ELECTROLYTE DISTRIBUTION  Electrolyte  Extracellular meq/liter  Intracellular meq/liter Function  Sodium  142  10  fluid balance, osmotic pressure  Potassium 5 100  Neuromuscular excitability acid-base balance  Calcium 5 - bones, blood clotting  Magnesium 2 123 enzymes  Total Positive ions  154 205   Electrolyte Distribution  Electrolyte Extracellular meq/liter  Intracellular meq/liter  Function  Chloride  105  2 fluid balance, osmotic pressure  Bicarbonate 24 8 acid-base balance  Proteins 16 55 osmotic pressure  Phosphate 2 149 energy storage  Sulfate 1 - protein metabolism  Total Negative ions 154 205

Electrolytes are the chemicals dissolved in the body fluid. The distribution has important consequences for the ultimate balance of fluids. Sodium chloride is found mostly in extracellular fluid, while potassium and phosphate are the main ions in the intracellular fluid.