Hyperkalemia is clinically more common because it can slow down the heart rate, even cardiac arrest can occur, and can cause neurological changes that may be life-threatening, so it is clinically necessary to deal with it promptly. The causes of hyperkalemia are the following: reduced renal sodium excretion, including acute renal failure, oliguria or advanced chronic renal failure, adrenocortical hormone synthesis; insufficient secretion, such as hyperaldosteronism, hypoaldosteronism, potassium-protective diuretics, long-term application of aminoglutethimide, spironolactone, etc.; also including intracellular potassium migration, such as acute hemolysis, tissue injury, tumor or inflammatory cell necrosis in large numbers , tissue hypoxia, shock, burns, excessive muscle spasm, etc.; acidosis and hyperkalemic periodic paralysis. The injection of the hypertonic saline agent mannitol can also cause intracellular potassium to move out of the cells due to intracellular dehydration and alteration of cell membrane permeability and cell metabolism, making the potassium in the blood relatively high. It is also possible that the input of potassium-containing drugs is too much, such as the commonly used potassium salt of penicillin, and when applied in large doses, the input is too much and too rapid, and hyperkalemia may occur. Hyperkalemia can also be caused by a high amount of stock blood input during blood transfusion and digitalis toxicity. If hyperkalemia occurs, you need to seek medical attention in a timely manner to avoid delaying the condition.