| 摘要 |
An apparatus is disclosed for monitoring a patient's blood pressure, non-invasively, in which a flexible diaphragm that encloses a liquid-filled chamber is compressed against tissue overlying an artery, with sufficient force to applanate the artery. A first control system optimizes the amount of artery applanation, which occurs at a transmural pressure of about zero, by modulating the volume of liquid within the chamber and noting the resulting effect on the pressure within the chamber. Since different pressure effects are realized according to the amount of artery applanation, an appropriate control signal can be produced that provides the optimum mean diaphragm pressure. In addition, a second control system servo controls the diaphragm position by controlling the amount of liquid within the chamber, to compensate for pressure variations due to arterial pulses. This minimizes variations in the artery diameter, whereby the pressure within the liquid-filled chamber closely follows the actual arterial pulse waveform. |
