Hypertension: systolic blood pressure ≥ 140, diastolic blood pressure ≥90. 1 hypertension (mild): systolic blood pressure 140 ~ 159, diastolic blood pressure 90 ~ 99. Grade 2 hypertension (moderate): systolic blood pressure 160 ~ 179, diastolic blood pressure 100 ~ 109. Grade 3 hypertension (severe): systolic blood pressure ≥ 180, diastolic blood pressure ≥ 1 10.
Extended data
Blood pressure refers to the lateral pressure of blood in blood vessels on the unit area of blood vessel wall, that is, pressure.
According to the international standard unit of measurement, the unit of pressure is Pa, that is, Newton/square meter (n/m2). The unit of pa is small, and the blood pressure value is usually expressed in kilopascals (kPa) (1mmHg is equal to 0. 133kPa).
Blood pressure in various blood vessels is called arterial blood pressure, venous blood pressure and capillary blood pressure respectively. Arterial blood pressure refers to the pressure of blood on arterial blood vessels, generally referring to aortic pressure. Average blood pressure = (systolic pressure +2× diastolic pressure) /3 = 1/3 systolic pressure +2/3 diastolic pressure.
When the heart contracts, the left ventricle will pump blood out to the aorta, and the aortic pressure will produce high blood pressure, also known as systolic blood pressure. Next, the heart will relax and blood will flow into the right atrium. At this time, the pressure is the lowest, which is called blood hypotension or diastolic pressure.