Hyperkalemia diagnosis


 * Associate Editor(s)-In-Chief: Priyamvada Singh, M.B.B.S. [mailto:psingh@perfuse.org]

Overview
Hyperkalemia (AE) or Hyperkalaemia (BE) is an elevated blood level (above 5.0 mmol/L) of the electrolyte potassium. The prefix hyper- means high (contrast with hypo-, meaning low). The middle kal refers to kalium, which is Latin for potassium. The end portion of the word, -emia, means "in the blood". Extreme degrees of hyperkalemia are considered a medical emergency due to the risk of potentially fatal arrhythmias.

Diagnosis
In order to gather enough information for diagnosis, the measurement of potassium needs to be repeated, as the elevation can be due to hemolysis in the first sample. Generally, blood tests for renal function (creatinine, blood urea nitrogen), glucose and occasionally creatine kinase and cortisol will be performed. Calculating the trans-tubular potassium gradient can sometimes help in distinguishing the cause of the hyperkalemia.

In many cases, renal ultrasound will be performed, since hyperkalemia is highly suggestive of renal failure.

Also, electrocardiography (EKG/ECG) may be performed to determine if there is a significant risk of cardiac arrhythmias