摘要 |
A photoelectric transparency detector juxtaposed under a certain contact pressure with the tip of a finger works into a computer also receiving the values of an astringent pressure simultaneously applied to another part of the finger by an inflatable air cushion of a flow-blocking cuff. The computer calculates a predetermined fraction, specifically one-half, of the sum of several air-pressure values measured during a period of progressive relaxation of the astringent pressure, taken at instants coinciding with certain points of a continuous curve representing changes in the mean transparency of a skin area contacted by the detector, which constitutes a close approximation of systolic blood pressure. Diastolic blood pressure may be measured during a heartbeat immediately following a low point of the mean-transparency curve.
|