DRG Category: 640

Mean LOS: 5.1 days

Description MEDICAL: Nutritional and Miscellaneous Metabolic Disorders with Major CC

classification section:



Normal serum levels of potassium range from 3.5 to 5.0 mEq/L. Hyperkalemia, defined as a potassium level greater than 5.0 mEq/L, is usually associated with impaired renal function, but it may also be produced by treatments for other disorders. Mild hyperkalemia is from 5.0 to 6.0 mEq/L, moderate hyperkalemia is from 6.1 to 7.0 mEq/L, and severe hyperkalemia is 7.0 mEq/L and greater. It is diagnosed in up to 8% of hospitalized patients. Increased potassium intake, reduction in potassium excretion, and shift of potassium out of the cells all may result in hyperkalemia. Because potassium plays a key role in cardiac function, a high serum potassium level is of great concern. It is sometimes the first symptom of cardiac arrest.

Potassium functions as the major intracellular cation and balances sodium in the extracellular fluid (ECF) to maintain electroneutrality in the body. It is excreted by the kidneys. The normal ratio is approximately 40 mEq of potassium in 1 L of urine. Potassium is not stored in the body and needs to be replenished daily through dietary sources. It is also exchanged for hydrogen when changes in the body's pH call for a need for cation exchange. This situation occurs in metabolic alkalosis or other alterations that lead to increased cellular uptake of potassium, including insulin excess and renal failure. Potassium is regulated by two stimuli, aldosterone and hyperkalemia. Aldosterone is secreted in response to high renin and angiotensin II or hyperkalemia. The plasma level of potassium, when high, also increases renal potassium loss.