Fluid and electrolyte problems in renal and urologic disorders.

Because the kidneys are primarily responsible for the regulation of fluid and electrolyte balance, acute or chronic changes in renal function can result in multiple imbalances. Acutely, the rapidity of onset of renal deterioration makes nursing assessment and intervention critical to the prevention of complications and potentially fatal outcomes. For patients with chronic renal failure, nursing assessment and intervention are equally significant, since there is an absence of renal regulatory mechanisms. In renal failure, acute or chronic, one most commonly sees patients who have a tendency to develop hypervolemia, hyperkalemia, hyperphosphatemia, hypocalcemia, and bicarbonate deficiency (metabolic acidosis). Sodium is generally retained, but may appear normal, or hyponatremic, because of dilution from fluid retention. Following the relief of a urinary tract obstruction, hypovolemia, hyponatremia (true loss of sodium), hypokalemia, hypocalcemia, hypomagnesemia, and bicarbonate loss are most apt to occur. Electrolyte imbalances after urinary diversion vary depending on the site of urine diversion.