URINE VOLUME, FORMATION, & CONCENTRATION

• Urine is normally 95% water and 5% solutes.
• Urea - a metabolic waste product produced in the liver from the breakdown of protein and amino acids.
• The normal daily urine output is usually 1200 to 1500 mL, a range of 600 to 2000 mL is also considered normal.
• The kidneys continuously form urine as an ultrafiltrate of plasma.
• Antidiuretic hormone (ADH) - regulates blood pressure and regulates secretion of urine.
• To identify that the fluid is urine, it must be high in urea and creatinine content.
• Oliguria - a decrease in urine output.
• Anuria - cessation of urine flow.
• Nocturia - increase of excretion of urine during the night.
• Polyuria - increase in daily urine volume, usually associated with diabetes mellitus and diabetes insipidus.
• Urea - primary organic component of urine.
• Creatinine - product of metabolism of creatine by muscles.
• Uric Acid - product of breakdown of nucleic acid in food and cells.
• Chloride - primary inorganic component.
• Sodium - Primary form salt, varies by intake.
• Potassium - combined with chloride and other salts.
• Phosphate - combines with sodium to buffer the blood.
• Ammonium - regulates blood and tissue fluid acidity.
• Calcium - combines with chloride, sulfate, and phosphate.
• Diabetes Mellitus - defect either in the pancreatic production of insulin or in the body's response to insulin.
• Diabetes Insipidus - a condition where the body does not produce enough antidiuretic hormone.
• Polydipsia - excessive thirst, excessive urination, and excessive fluid intake.