If the cuff is wrapped too tightly when measuring blood pressure, it will have an effect on the value of the blood pressure and the measured blood pressure will not be standard. The patient should be seated with the popliteal artery level with the heart, and the cuff should not be too tight or too loose to fit a finger, so that the measured blood pressure is normal, and the patient should not exert himself or cough during the measurement. Blood pressure is the lateral pressure of the blood vessel wall, and blood pressure measurement can monitor the presence of hypertension, blood flow in the blood vessels and the elasticity of the vessel wall. Blood pressure is dynamic in the blood vessels, and the value of blood pressure measured at each stage is different at each time, and the value of blood pressure in a quiet state and in an active state is also different. 24-hour ambulatory blood pressure monitoring is required to diagnose hypertension.