Theory of measuring human blood pressure

Theory of measuring human blood pressure

The theory of blood pressure measurement is based on the turbulence that can be generated by blood flow through narrowed arterial conduits. Blood pressure is the pressure of blood flow against the walls of the arteries. The blood pressure drop in the larger arteries is small, and the brachial artery of the upper arm is generally measured...
Continue to inflate to make the mercury column rise by 20~30mmHg and then slowly release the airbag.

When the pressure of the balloon decreases, equal to or slightly lower than the systolic blood pressure, the blood flow suddenly flows into the compressed and narrowed blood vessels, resulting in turbulent flow. The first sound of blood flow can be heard, and the mercury column reading is systolic blood pressure.

When the pressure of the air bag continues to decrease, when the pressure is equal to or slightly lower than the diastolic pressure, the air bag will no longer compress the blood vessel wall, the blood flow is completely unobstructed, and the sound of blood flow cannot be heard, and the reading is the diastolic pressure.

In addition, it is recommended to rest for 15 minutes before measuring blood pressure, do not drink coffee, strong tea, etc., in order to reduce the influencing factors of blood pressure and make blood pressure measurement more accurate.