Method for determining diastolic arterial blood pressure in a subject

Claim 1

A method of determining a measure of the diastolic arterial blood pressure in a subject comprising the steps of: a. establishing, in response to a sequence of occlusive pressure waveform peaks and corresponding occlusive cuff pressure values occurring during deflation of an occlusive cuff, a sequence of mid-point co-ordinates, wherein one co-ordinate of each mid-point is an average of the peak amplitudes of two successive pressure waveforms and the other co-ordinate of each mid-point is an average of the occlusive cuff pressure values corresponding to each of said two peaks, b. grouping every mid-point into an alternate one of at least two series, c. determining the value of slope of each of a plurality of line segments, wherein each segment joins a pair of adjacent mid-points in one of said sequences, d. testing each of said slope values against pre-defined limits to determine whether any of said mid-points is attributable to a negator or a reversal, e. removing any pressure waveform peak and its corresponding occlusive cuff pressure value attributable to a negator or a reversal from the sequence and repeating steps (a), (b), (c) and (d) until substantially all pressure waveform peaks attributable to either negators or reversals have been removed, f. comparing the slope of each segment in each series against a pre-defined threshold and, in response thereto, choosing an appropriate one of the segments comprising each series, g. choosing an appropriate pressure waveform peak amplitude value that precedes the leading mid-point associated with the chosen segment in each series, h. selecting one of the resulting chosen pressure waveform peak amplitude values as the diastolic measure.

Claim 2

A method of determining a measure of the diastolic arterial blood pressure in a subject comprising the steps of: a. establishing, in response to a sequence of occlusive pressure waveform peaks and corresponding occlusive cuff pressure values occurring during deflation of an occlusive cuff, a sequence of mid-point co-ordinates, wherein one co-ordinate of each mid-point is an average of the peak amplitudes of two successive pressure waveforms and the other co-ordinate of each mid-point is an average of the occlusive cuff pressure values corresponding to each of said two peaks, b. grouping every mid-point into an alternate one of at least two series, c. determining the value of slope of each of a plurality of line segments, wherein each segment joins a pair of adjacent mid-points in one of said sequences, d. testing each of said slope values against pre-defined limits to determine whether any of said mid-points is attributable to a negator or a reversal, e. removing any pressure waveform peak and its corresponding occlusive cuff pressure value attributable to a negator or a reversal from the sequence and repeating steps (a), (b), (c) and (d) until substantially all pressure waveform peaks attributable to either negators or reversals have been removed, f. comparing the slope of each segment in each series against a pre-defined threshold and, in response thereto, choosing an appropriate one of the segments comprising each series, g. choosing an appropriate pressure waveform peak amplitude value that precedes the leading mid-point associated with the chosen segment in each series, h. selecting one of the resulting chosen pressure waveform peak amplitude values as the diastolic measure.