A High Potassium Level

Potassium acts as an electrolyte -- a substance that conducts electrical impulses that power the heart and prompt the muscles to contract. Potassium also works with enzymes to speed up chemical reactions in the body. Although the body needs potassium for survival, too much potassium poses serious risks for the muscles and cardiovascular system.

Significance

High potassium levels present a danger due to the way in which potassium aids in heart and muscle function. When too much potassium builds up in the bloodstream, it increases the risk for muscle paralysis, muscle weakness, absent pulse, difficulty breathing, irregular heartbeat and slow pulse.

Causes

A high potassium level -- called hyperkalemia -- occurs when the kidneys do not excrete enough potassium or when potassium shifts from inside the cells to the extracellular space between cells. Addison's disease, hypoaldosteronism, kidney failure, congenital adrenal hyperplasia, renal tubular acidosis, systemic lupus erythematosus and pseudohypoaldosteronism cause the kidneys to retain too much potassium. Acidosis, insulin deficiency, tissue damage, uncontrolled diabetes, insulin resistance, tumor lysis syndrome and familial hyperkalemic periodic paralysis cause potassium to shift from inside the cells to outside the cells. Medications that affect the amount of potassium excreted from the body may also cause hyperkalemia

Identification

The potassium blood test determines how much potassium you have in your bloodstream. If you have an existing medical condition, such as kidney disease, your doctor may order the potassium test as part of the basic metabolic panel (BMP). The BMP also helps determine the amounts of creatinine, blood urea nitrogen, calcium, sodium, glucose, chloride and carbon dioxide in your blood. The normal amount of potassium in the cells ranges from 3.7 to 5.2 mEq/L. In some cases, improper handling of a blood sample damages the red blood cells, allowing potassium to leak out of those cells. If this happens, you will need to give a second blood sample.

Treatment

Hyperkalemia needs immediate treatment when it causes cardiac changes on an electrocardiogram or when the potassium level increases quickly in a short amount of time. Someone with decreased renal function or increased blood acidity also requires emergent treatment for this condition. Physicians administer drugs, such as calcium gluconate, furosemide, albuterol, sodium polystyrene sulfonate and insulin, to reduce a high potassium level. The drug used depends on the severity of the hyperkalemia and the results of additional urine and blood testing.

Prevention

If you have a condition that puts you at risk for an elevated potassium level, your doctor may advise you to reduce the amount of potassium you consume each day. Foods such as bananas, tomatoes, yams, potatoes and chocolate have high levels of potassium, so you should avoid them or eat them in very limited amounts. Your doctor may also order regular blood tests to make sure your potassium level does not exceed the normal range.