How is hyperkalemia diagnosed?
Blood is withdrawn from a vein (like other blood tests). The potassium concentration of the blood is determined in the laboratory. If hyperkalemia is suspected, an electrocardiogram (ECG or EKG) is often performed, since the ECG may show changes typical for hyperkalemia in moderate to severe cases. The ECG will also be able to identify cardiac arrhythmias that result from hyperkalemia.