Patent ID: 7641614
Filing Date: 2010-01-05
Classification: A61B

Abstract:
1. A method for performing a circulatory measurement on an extremity of a subject, the method comprising: measuring a plethysmographic signal of a plethysmographic sensor disposed on the extremity of the subject at a plurality of heights of the sensor, relative to the heart of the subject, and at a plurality of externally applied pressures at each height of the sensor; while measuring the plethysmographic signal, using a solid protrusion to externally apply a focal pressure to the extremity of the subject, the focal pressure having a value that may vary; determining a relationship characterizing variation of the plethysmographic signal with the plurality of heights of the sensor and the plurality of externally applied pressures; and deriving an arterial blood pressure feature based on at least the relationship characterizing variation of the plethysmographic signal with the plurality of heights of the sensor and the plurality of externally applied pressures, and on an instantaneously measured plethysmographic signal and height of the sensor relative to the heart of the subject.