HLSC 2110U Lecture Notes - Lecture 20: Renal Function, Fluid Compartments, Extracellular Fluid
Document Summary
Balance is central to management of illnesses. Measurement of sodium, potassium, urea, creatine, chloride, and bicarbonate most commonly requested as it tells a lot about fluid and electrolyte status and kidney function. Body is made up mostly of water. Average person weighing 70 kg contains 42 l of water intracellular fluid = 28 l. Plasma = 3. 5 l and interstitial fluid = 10. 5 l. Intracellular fluid loss causes cellular dysfunction and is noted by fatigue, confusion, and coma. Extracellular fluid loss causes circulatory collapse, kidney failure, and shock. Positively and negatively charged ions in solution in all body fluids. Intracellularly the main anions are protein and phosphate. Extracellularly the main anions are chloride and bicarbonate. Urea and creatine concentrations given an indication of kidney function. Increased concentrations indicate a decreased glomerular filtration rate. Ratio of two variables: amount of solute and the amount of solvent. Concentration can change because either one or both variables have changed.