20: Tumors of the bladder Flashcards
What syndrome and blood changes are associated with using the stomach for urinary diversion? Also, list the associated abnormalities, symptoms, and treatment.
The stomach is associated with severe metabolic alkalosis, with a decrease in K+ and Cl–, and an increase in pH. The associated abnormality is elevated aldosterone. Symptoms include lethargy, muscle weakness, respiratory insufficiency, seizures, and ventricular arrhythmia. Treatment involves H2 blockers, proton pump inhibitors, and if life-threatening, arginine hydrochloride infusion and/or removal of the segment.
What happens to serum potassium levels during alkalosis, and what is the physiological explanation for this change?
During alkalosis, serum potassium levels decrease. The increase in blood pH leads to the movement of hydrogen ions out of the cells, and in exchange, potassium ions move into the cells, resulting in a decrease in extracellular potassium concentration.
Explain the syndrome, blood changes, associated abnormalities, symptoms, and treatment when using the ileum/colon for urinary diversion.
The ileum/colon is associated with hyperchloremic metabolic acidosis, with a decrease in K+ and an increase in Cl–, along with a decrease in pH. Associated abnormalities are total-body potassium depletion and hypocalcemia. Symptoms include fatigue, anorexia, lethargy, and weakness. Treatment consists of potassium citrate, sodium citrate, citric acid, sodium bicarbonate, chlorpromazine, and nicotinic acid.
Why does the use of the ileum/colon for urinary diversion lead to hypokalemia?
The use of the ileum/colon leads to hyperchloremic metabolic acidosis, causing initial potassium movement out of the cells. The kidneys respond by excreting H+ and K+ to correct the acidosis, and increased aldosterone secretion also promotes potassium excretion. Chronic urinary loss of potassium in this diversion further contributes to hypokalemia.
Describe the electrolyte disturbances, associated abnormalities, symptoms, and treatment when the jejunum is used for urinary diversion.
The jejunum is associated with hyperkalemic, hypochloremic metabolic acidosis, characterized by a decrease in Na+ and Cl–, and an increase in K+, with a decrease in pH. Abnormalities include elevated renin and angiotensin. Symptoms are lethargy, nausea, vomiting, dehydration, and muscle weakness. Treatment is intravenous hydration, sodium bicarbonate, thiazide, and if life-threatening, removal of the segment.
Why does the use of the jejunum for urinary diversion lead to hyperkalemia?
The jejunum’s use for urinary diversion leads to hyperkalemia through increased absorption of potassium, loss of sodium and chloride, and the complex response of the renin-angiotensin-aldosterone system, which may prioritize sodium retention over potassium excretion.
How do the large intestine and small intestine differ in terms of hyperkalemia or hypokalemia when used for urinary diversion?
The small intestine (e.g., jejunum) may lead to hyperkalemia due to increased potassium absorption and altered sodium and chloride balance. The large intestine (e.g., ileum/colon) often results in hypokalemia due to hyperchloremic metabolic acidosis, increased aldosterone secretion, and chronic urinary loss of potassium.
