High Potassium & Kidneys

The kidneys remove unwanted substances, toxins and waste products from the body. They also remove excess potassium, helping the body maintain normal serum potassium levels. Potassium is important for nerve, heart and muscle function. High levels of potassium in the serum can cause heart problems.

High Potassium

Hyperkalemia occurs when there is a higher-than-normal level of potassium in the blood. According to "The Hospitalist Manual," weakness, body ache and fatigue are common symptoms of hyperkalemia. Some effects of hyperkalemia on the nerves are a sensation numbness and tingling in parts of the body, palpitations or irregular heartbeats and paralysis. Several factors can cause hyperkalemia including excessive intake of potassium, certain diseases and factors that affect removal of potassium from the body.

Role of the Kidneys

One of the factors that affects the kidneys' ability to remove potassium from the body involves the adrenal hormone aldosterone. Aldosterone stimulates the kidneys to remove more potassium than sodium from the body. When the adrenal glands produce too little aldosterone, the kidneys retain more potassium in the body and this can cause hyperkalemia. Kidney failure can also lead to hyperkalemia. Here, the kidneys are unable to remove waste products from the body and this leads to accumulation of substances such as potassium. Medications, including potassium-sparing diuretics, stimulate the kidneys to retain potassium and can lead to hyperkalemia as well.

Complications

Cardiac arrest is a complication of hyperkalemia, notes MedlinePlus. In this condition, the heart stops beating. Cardiac arrest can occur as a result of ventricular arrhythmia or bradycardia -- potential effects of hyperkalemia. In ventricular arrhythmia, the heart twitches or quivers instead of beating normally, while bradycardia describes a condition where the heart beats extremely slowly. Cardiac arrest can lead to death in the absence of quick treatment.

Tests and Exams

Hyperkalemia may go undiagnosed because its symptoms are vague. This disorder is diagnosed by measuring the amount of potassium in the blood. Creatinine and urea nitrogen levels are also taken to indicate if the kidneys are working properly because kidney dysfunction can cause hyperkalemia. Heart function is also monitored for the presence of abnormal heart rhythms such as arrhythmia.

Treatment

Because cardiac arrest can happen anytime during treatment, hyperkalemia treatment involves close monitoring that is done in a hospital. Immediate treatment of this condition includes removing excess potassium from the body and protecting the heart from the effects of hyperkalemia.

People whose kidneys don't work well may require dialysis -- a procedure during which potassium is removed from the body with a medical device. In long term treatment of hyperkalemia, chronic kidney failure patients may need to limit their intakes of potassium and may be given medications that reduce blood levels of potassium.