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Hyperkalemia
Definition:
Hyperkalemia is a condition caused by higher than normal levels of potassium in the bloodstream. Alternative Names:
High potassium; Potassium - high Text Continues Below
Causes, incidence, and risk factors:
Potassium has many functions in the body. It helps to regulate the activity of all muscle tissue -- smooth muscles (such as the muscles in the intestines), the muscles of the heart, and skeletal muscles. Potassium is part of the enzyme reactions in digestion and metabolism. It is also part of homeostasis, the mechanism that maintains a balance between the many electrical and chemical processes of the body. Almost all (98%) potassium in the body is found inside the cells (intracellular). Only about 2% occurs in the fluids outside of the cells (extracellular). Potassium can move into and out of cells. Blood tests reflect only the extracellular potassium levels, and do not indicate the amount of potassium within the cells. Movement of potassium into or out of cells can change the blood potassium level (serum potassium) when there is no change in the total amount of potassium in the body. Hyperkalemia occurs when the level of potassium in the bloodstream is higher than normal. This may be related to increase in total body potassium or excessive release of potassium from the cells into the bloodstream. The kidneys normally excrete excess potassium from the body. Therefore, most cases of hyperkalemia are caused by disorders that reduce the kidneys' ability to excrete potassium. Insufficient kidney function may result from disorders including (but not limited to):
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