​Oscillographic method

- Apr 19, 2018-

The oscillometric method is also called the oscillation method. It is a relatively advanced electronic measurement method developed in the 90s.

The principle is briefly described as follows:

First put the cuff on the arm and automatically inflate the cuff to a certain pressure (usually 30~50 mmHg higher than the systolic blood pressure) and then stop deflation. When the pressure reaches a certain level, the blood flow can pass. Vascular, and there is a certain oscillation wave, the oscillation wave propagates to the pressure sensor through the trachea, and the pressure sensor can detect the pressure and fluctuation in the measured cuff in real time. Gradually deflate, the oscillation wave is getting bigger and bigger. Re-breathing The looser the contact between the cuff and the arm, the pressure and fluctuations detected by the pressure sensor become smaller and smaller. Select the moment of maximum fluctuation as the reference point. Based on this point, look for the fluctuating point with a peak value of 0.45. This is the systolic pressure. Look back to the fluctuation point with a peak value of 0.75. This corresponds to the diastolic pressure. The pressure corresponding to the point with the highest volatility is the average pressure. It is worth mentioning that this constant is 0.45 and 0.75. It is not the same for each manufacturer, and should be based on the results of clinical tests. Moreover, it is also possible for large manufacturers to segment different blood pressures and set different constants.

Several internationally advanced companies have developed MWI technology, a technology that measures blood pressure during the process of pressurization, which has greatly shortened the measurement time; at the same time, it has also greatly enhanced the linear pressure technology. Improve the measurement accuracy.