The clinical manifestations of hyperkalemia mainly affect the cardiovascular system, often presenting with slowed heart rate and various arrhythmias. When the blood potassium level is between 6.6 and 8.0 mmol/L, a tent-shaped T-wave can be observed. Rapid increases in blood potassium can lead to ventricular tachycardia, and even ventricular fibrillation. A gradual increase in blood potassium can cause conduction blocks, and in severe cases, cardiac arrest. Sudden death in severe hyperkalemia is mainly due to ventricular fibrillation and cardiac arrest. The second aspect is symptoms related to the neuromuscular system. As the concentration of potassium ions in the extracellular fluid increases, the resting membrane potential drops, leading to muscle weakness and even paralysis, typically more pronounced in the lower limbs and extending upward along the trunk. In severe cases, some patients may experience difficulty in swallowing and breathing difficulties. Symptoms involving the central nervous system mainly include restlessness, confusion, and fainting.