以下节录自内科学圣经：Harrison's Principles of Internal Medicine Chapter 41. Fluid and Electrolyte Disturbances 重点我都画起来了，里面该有的都有。 真正用来排钾的东西... 後面有写。 Severe hyperkalemia requires emergent treatment directed at minimizing membrane depolarization, shifting K+ into cells, and promoting K+ loss. In addition, exogenous K+ intake and antikaliuretic drugs should be discontinued. Administration of calcium gluconate decreases membrane excitability. The usual dose is 10 mL of a 10% solution infused over 2 to 3 min. The effect begins within minutes but is short-lived (30 to 60 min), and the dose can be repeated if no change in the electrocardiogram is seen after 5 to 10 min. Insulin causes K+ to shift into cells by mechanisms described previously and will temporarily lower the plasma K+ concentration. Although glucose alone will stimulate insulin release from normal pancreatic cells, a more rapid response generally occurs when exogenous insulin is administered (with glucose to prevent hypoglycemia). A commonly recommended combination is 10 to 20 units of regular insulin and 25 to 50 g of glucose. Obviously, hyperglycemic patients should not be given glucose. If effective, the plasma K+ concentration will fall by 0.5 to 1.5 mmol/L in 15 to 30 min and the effect will last for several hours. Alkali therapy with intravenous NaHCO3 can also shift K+ into cells. This is safest when administered as an isotonic solution of 3 ampules per liter (134 mmol/L NaHCO3) and ideally should be reserved for severe hyperkalemia associated with metabolic acidosis. Patients with end-stage renal disease seldom respond to this intervention and may not tolerate the Na+ load and resultant volume expansion. When administered parenterally or in nebulized form, 2-adrenergic agonists promote cellular uptake of K+ (see above). The onset of action is 30 min, lowering the plasma K+ concentration by 0.5 to 1.5 mmol/L, and the effect lasts 2 to 4 h. Removal of K+ can be achieved using diuretics, cation-exchange resin, or dialysis. Loop and thiazide diuretics, often in combination, may enhance K+ excretion if renal function is adequate. Sodium polystyrene sulfonate is a cation-exchange resin that promotes the exchange of Na+ for K+ in the gastrointestinal tract. Each gram binds 1 mmol of K+ and releases 2 to 3 mmol of Na+. When given by mouth, the usual dose is 25 to 50 g mixed with 100 mL of 20% sorbitol to prevent constipation. This will generally lower the plasma K+ concentration by 0.5 to 1.0 mmol/L within 1 to 2 h and last for 4 to 6 h. Sodium polystyrene sulfonate can also be administered as a retention enema consisting of 50 g of resin and 50 mL of 70% sorbitol mixed in 150 mL of tap water. The sorbitol should be omitted from the enema in postoperative patients due to the increased incidence of sorbitol-induced colonic necrosis, especially following renal transplantation. The most rapid and effective way of lowering the plasma K+ concentration is hemodialysis. This should be reserved for patients with renal failure and those with severe life-threatening hyperkalemia unresponsive to more conservative measures. Peritoneal dialysis also removes K+ but is only 15 to 20% as effective as hemodialysis. Finally, the underlying cause of the hyperkalemia should be treated. This may involve dietary modification, correction of metabolic acidosis, cautious volume expansion, and administration of exogenous mineralocorticoid. -- 个人网页： http://pcman.sayya.org/ 上面有自画像及各种联络资讯 Blog: http://pcman.sayya.org/blog.php?id=pcman PCMan 全系列 BBS 连线软体 http://pcman.ptt.cc/ http://pcmanx.csie.net/ 新酷音输入法 for Windows http://chewing.csie.net/ IE Tab Firefox plugin/extension http://ietab.mozdev.org/ --

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