FLEXIBLE DIAPHRAGM TONOMETER AND METHOD OF USE

摘要

A pressure waveform monitor (10) for non-invasively monitoring the pressure waveform inside a vessel, such as an artery, includes a flexible diaphragm (33) extended across an opening of a containing (29) containing a fluid (23). The flexible diaphragm (33) is placed against tissue surrounding an artery such that arterial pressure causes a deflection in the diaphragm (33). A deflection in the diaphragm (33) causes the fluid (23) to be redistributed throughout the container (29) which is effectively divided into an array of volume compartments. The relative volume distribution is determined through impedance plethysmography. The diaphragm (33) is maintained in a calibrated position by maintaining the array of volume compartments at relatively unchanged volumes. When the relative volumes remain essentially unchanged, calibrated tonometry is possible. The pressure within the container (29) is then used to determine the pulse waveform and the pressure within the artery.