The difference between invasive and noninvasive blood pressure measurements is generally less than 10 mm Hg. Generally, noninvasive blood pressure measurements can meet clinical needs, and the cuff blood pressure monitors and pointer blood pressure monitors that we usually use are noninvasive blood pressure measurements, which are easy to operate, accurate and popular. Invasive blood pressure measurement is also commonly used clinically, which can truly reflect blood pressure, and is obtained directly through arterial puncture, and is mostly used during major surgery, as it can reflect instantaneous real-time blood pressure, such as valve replacement surgery for rheumatic heart disease, bypass surgery for myocardial infarction, and in critical patients such as cardiogenic shock, respiratory and circulatory failure, and heart failure patients, when necessary. Invasive blood pressure monitoring is performed to develop treatment plans. Because of the expertise required to perform invasive blood pressure, it is not widely available, and the mainstream is still non-invasive blood pressure.