hypokalemiaandpotassiumdeficit-免費閱讀
【正文】 查體： ℃ , 嗜睡，醒后煩躁，皮膚干熱，明顯腹脹。 Hypokalemia and Potassium Deficit ? (1) Concept ? (2) Causes and mechanism ? (3) Effect on the body ? (4) Principle of treatment (1) Concept ? Hypokalemia indicates the [K+] in plasma is mmol/L. ? If the hypokalemia is caused by the movement of K+ from ECF to ICF, ? reduced [K+] ≠ K deficiency in the body. (2) Causes and mechanism ? 1) Decreased intake ? 2) Excessive loss of K+ ? 3) More moving of K+ into cells ? 4) Blood dilution 1)Decreased intake ? Since food is the main source of potassium in the body, fast, anorexia or inability to eat may cause hypokalemia. ? At the same time, there is still loss of potassium from kidneys (5~10 mmol/ day at least). Renal excretion of potassium continuously amount of K+ excretion Normal 38~150 mmol/day No K intake 1~3 day 50 mmol/ day 4~7 day 20 mmol/ day 10 day 5~10 mml/ day 2) Excessive loss of K+ ? (a) From gastrointestinal tract ? (b) Excessive renal loss (a) From gastrointestinal tract The gastric and intestinal juices are rich in potassium. position [K+] (mmol/L) Gastric juice high acidity 10 low acidity 25 Bile 10 Juice in small intestine 20 Watery stool 40 Persistent vomiting, diarrhea, gastric suction and fistula are the mon ways to lose potassium directly. At the same time hypovolemia may lead to increased secretion of aldosterone. Increased aldosterone (caused by hypovolemia) will enhance the loss of potassium from gastrointestinal tract like the renal tubules. At the same time, loss of gastric juice may lead to metabolic alkalosis. (b) Excessive renal loss ? Renal loss is the main way to lose potassium. ? ① Hyperaldosteronism Primary hyperaldosteronism is caused by adrenal tumors. Secondary hyperaldosteronism is caused by markedly reduced effective arterial volume in congestive heart failure, liver cirrhosis and nephritic syndrome. Increased aldosterone secretion will increase the potassium loss from kidneys. Administration of large amount of glucocorticoids can also produce hypokalemia. ② Diuretics The most mon diuretics losing potassium are thiazines噻嗪類 , furosemide 速尿 and etha
教學課件相關推薦
鄂ICP備17016276號-1