Potassium is an important cation for maintaining neuromuscular excitability, and too much potassium is hyperkalemia. When blood potassium is greater than 5.5 mmol/L it is hyperkalemia, and when blood potassium is greater than 7.0 mmol/L it is severe hyperkalemia. The most important symptoms of hyperkalemia are: i. Muscle pain and weakness, perioral numbness, and in severe cases, limb muscle paralysis, and in more serious cases, the involvement of respiratory muscles can cause respiratory arrest. Secondly, potassium ions can affect the electrophysiological activities of the heart and inhibit the contractility of the heart muscle, which is prone to arrhythmia, bradycardia, and weak heart sound. Third, hyperkalemia can have gastrointestinal irritation symptoms, such as nausea, vomiting, abdominal pain and other symptoms. So hyperkalemia can be life-threatening and needs to be treated actively.