Patent Document ID: 8313439
Application ID: 12408345
Patent Flag: 1

Claim One:
1. A method for autonomous calibration of a pulse-transit-time monitoring device for measurement of arterial blood pressure, the method comprising: measuring a pulse transit time of a circulatory feature between a proximal sensor position and a distal sensor position, the proximal and distal sensor positions disposed along a single arterial transit path on a human body; parameterizing a modeled quantitative relationship among a set of quantities, at least one of which quantities is a quantity explicitly varying with distance along the transit path, wherein the transit path is treated in a lumped parameter model having at least three segments with respect to evaluation of the at least one quantity explicitly varying with distance along the transit path, wherein each quantity explicitly varying with distance along the transit path is a linear combination of terms, each term proportional to the length of each respective segment and an exponential function of the arterial blood pressure, and wherein the at least one quantity explicitly varying with distance is parametrized as a function of transmural pressure, pulse wave velocity, arterial blood pressure, vertical height of all loci along the transit path, and any external pressure on a body surface along the transit path; performing a measurement so as to provide a plurality of quantities from among the set of quantities; and solving the plurality of quantities, on the basis of the modeled quantitative relationship, so as to obtain the arterial blood pressure as a function of the measured pulse transit time.