A blood test for electrolytes can determine whether the body has an electrolyte disorder. The more important electrolytes in blood biochemistry are blood potassium, blood sodium and blood calcium, etc. If there is an abnormality between them, the human body will have corresponding lesions, such as hyperkalemia or hypokalemia, hypernatremia or hyponatremia, hypercalcemia or hypocalcemia. Blood potassium indicator: The blood potassium of the human body is between 3.5 millimoles per liter and 5.5 millimoles per liter. Whether it is hyperkalemia or hypokalemia, it will cause greater harm to the human body, and the seriousness can lead to cardiac arrhythmia, even cardiac arrest and other dangers. Blood sodium index: it is very important for maintaining the plasma osmotic pressure of the human body, when there is an abnormality of sodium metabolism of the human body, the human body will have symptoms such as edema, even trance, or even convulsions. Calcium indicator: If the blood calcium decreases, it will lead to osteoporosis, etc. If the blood calcium is too high, it will lead to fatigue and weakness, cardiac arrhythmia, nausea, vomiting and other symptoms.