Patent ID: 8348851
Filing Date: 2013-01-08
Classification: A61B

Abstract:
1. A blood pressure measurement device comprising: a cuff adapted to press a blood pressure measurement portion, wherein said cuff includes a large cuff for blocking a blood vessel, and a small cuff for detecting a pulse wave, wherein said large cuff and said small cuff are connected via a fluid resistance; a pressure control unit adapted to pressurize or depressurize an interior of said large cuff; a pressure sensor adapted to sense an internal pressure of said small cuff; a pulse wave signal extracting unit adapted to extract time-series data of a pulse wave signal superposed on the cuff internal pressure sensed by said pressure sensor, in a process in which said pressure control unit pressurizes or depressurizes said large cuff; and a blood pressure determination unit adapted to determine a diastolic blood pressure value and a systolic blood pressure value based on the extracted pulse wave signal time-series data; a display unit adapted to display a pulse waveform corresponding to a pulse wave signal of at least one period, together with a value of a cuff internal pressure corresponding to the pulse wave signal; wherein the diastolic blood pressure value is determined based on (i) the cuff pressure when the phase difference between the bottom point produced ahead of the peak point of the pulse wave signal and the appearance of the maximum gradient point is smaller than a first predetermined threshold value, or (ii) the cuff pressure when the displacement of the bottom point produced ahead of or behind the peak point of the pulse wave signal from the maximum gradient point is smaller than a second predetermined value; and wherein the systolic blood pressure value is determined based on (iii) the cuff pressure value at a point where the phase difference between the bottom point produced ahead of the peak point of the pulse wave signal and the appearance of the maximum gradient point shows a large change having no value continuity when the phase difference for each pulse wave signal is checked in order from a pulse wave signal corresponding to the lowest cuff pressure, or (iv) the cuff pressure value at a point where the displacement of the bottom point produced ahead of or behind the peak point of the pulse wave signal from the maximum gradient point shows a large change having no value continuity when the displacement for each pulse wave signal is checked in order from a pulse wave signal corresponding to the lowest cuff pressure.