Patent ID: 7029448

Claim:
An electronic blood pressure monitor, comprising: a cuff adapted for attachment to a subject and pressurized and depressurized to measure said subject's blood pressure; a pulse wave detector detecting said subject's pulse wave as said cuff occludes said subject and comprising a waveform parameter calculator calculating a wave form parameter indicative of a feature of a waveform of a pulse wave detected; a mean blood pressure estimator estimating said subject's estimated mean blood pressure from said pulse wave detected by said pulse wave detector; a diastolic blood pressure detector detecting said subject's diastolic blood pressure comprising a diastolic blood pressure calculator using said waveform parameter to calculate diastolic blood pressure; and a systolic blood pressure calculator calculating said subject's systolic blood pressure from said estimated mean arterial pressure, said detected diastolic blood pressure and a waveform of said pulse; and a waveform distortion corrector correcting said waveform parameter to cancel an error introduced by a distortion of a detected pulse wave relative to said intra-arterial waveform into systolic blood pressure calculated, wherein said mean blood pressure estimator employs said waveform parameter to determine a reference pressure point within any range from a point of no more than systolic blood pressure to a point no less than a diastolic blood pressure and with reference to said reference pressure point calculates the estimated mean arterial pressure by using said waveform parameter correlated with an average value of an intra-arterial pressure waveform; and said systolic blood pressure calculator correlates said diastolic blood pressure and said estimated mean arterial pressure to said pulse waveform's maximum and average values and calculates a blood pressure corresponding to said pulse waveform's maximum value point to determine systolic blood pressure.