Method and apparatus for systolic blood pressure measurement

Claim 1

A method for measuring systolic blood pressure, comprising the steps of: attaching a pressure cuff to a patient adjacent to a blood vessel; pressurizing the cuff sufficiently to occlude the blood vessel; alternately measuring counter pressure pulses in the cuff and decrementing the cuff pressure; forming a table of raw, unsmoothed data measurements from the measured counter pressure pulses corresponding to the decremented cuff pressure; selecting an upper systolic threshold limit and a lower systolic threshold limit on either side of approximately 50% of a maximum measured counter pressure; scanning the table from the maximum measured counter pressure towards larger corresponding cuff pressures and finding a first measured counter pressure less than the lower systolic threshold, a first measured counter pressure greater than the lower systolic threshold and interpolating therebetween to arrive at a lower threshold result; associating the lower threshold result with a lower systolic pressure; scanning the table from the maximum measured counter pressure towards larger corresponding cuff pressures and finding the first measured counter pressure less than the upper systolic threshold, a first measured counter pressure greater than the upper systolic threshold and interpolating therebetween to arrive at an upper threshold result; associating the upper threshold result with an uppersystolic pressure; and averaging the upper and lower systolic pressure to arrive at a systolic pressure, whereby an accurate systolic pressure is obtained from raw, unsmoothed measured counter pressure data, even including random respiration artifacts, without smoothing the raw data.

Claim 2

A method for measuring systolic blood pressure, comprising the steps of: attaching a pressure cuff to a patient adjacent to a blood vessel; pressurizing the cuff sufficiently to occlude the blood vessel; alternately measuring counter pressure pulses in the cuff and decrementing the cuff pressure; forming a table of raw, unsmoothed data measurements from the measured counter pressure pulses corresponding to the decremented cuff pressure; selecting an upper systolic threshold limit and a lower systolic threshold limit on either side of approximately 50% of a maximum measured counter pressure; scanning the table from the maximum measured counter pressure towards larger corresponding cuff pressures and finding a first measured counter pressure less than the lower systolic threshold, a first measured counter pressure greater than the lower systolic threshold and interpolating therebetween to arrive at a lower threshold result; associating the lower threshold result with a lower systolic pressure; scanning the table from the maximum measured counter pressure towards larger corresponding cuff pressures and finding the first measured counter pressure less than the upper systolic threshold, a first measured counter pressure greater than the upper systolic threshold and interpolating therebetween to arrive at an upper threshold result; associating the upper threshold result with an uppersystolic pressure; and averaging the upper and lower systolic pressure to arrive at a systolic pressure, whereby an accurate systolic pressure is obtained from raw, unsmoothed measured counter pressure data, even including random respiration artifacts, without smoothing the raw data.

Claim 4

An apparatus for measuring systolic blood pressure, comprising the steps of: means for attaching a pressure cuff to a patient adjacent to a blood vessel; means for pressurizing the cuff sufficiently to occlude the blood vessel; means for alternately measuring counter pressure pulses in the cuff and decrementing the cuff pressure; means for forming a table of raw, unsmoothed data measurements from the measured counter pressure pulses corresponding to the decremented cuff pressures; means for selecting an upper systolic threshold limit and a lower systolic threshold limit on either side of approximately 50% of a maximum measured counter pressure; means for scanning the table from the maximum measured counter pressure towards larger corresponding cuff pressures and finding a first measured counter pressure less than the lower systolic threshold, a first measured counter pressure greater than the lower systolic threshold and interpolating therebetween to arrive at a lower threshold result; means for associating the lower threshold result with a lower systolic pressure; means for scanning the table from the maximum measured counter pressure towards larger corresponding cuff pressures and finding a first measured counter pressure less than the upper systolic threshold, a first measured counter pressure greater than the upper systolic threshold and interpolating therebetween to arrive at an upper threshold result; associating the upper threshold result with an upper systolic pressure; and means for averaging the upper and lower systolic pressure to arrive at a systolic pressure, whereby an accuratesystolic pressure is obtained from raw, unsmoothed measured counter pressure data, even including random respiration artifacts, without smoothing the raw data.

Claim 5

An apparatus for measuring systolic blood pressure, comprising the steps of: means for attaching a pressure cuff to a patient adjacent to a blood vessel; means for pressurizing the cuff sufficiently to occlude the blood vessel; means for alternately measuring counter pressure pulses in the cuff and decrementing the cuff pressure; means for forming a table of raw, unsmoothed data measurements from the measured counter pressure pulses corresponding to the decremented cuff pressures; means for selecting an upper systolic threshold limit and a lower systolic threshold limit on either side of approximately 50% of a maximum measured counter pressure; means for scanning the table from the maximum measured counter pressure towards larger corresponding cuff pressures and finding a first measured counter pressure less than the lower systolic threshold, a first measured counter pressure greater than the lower systolic threshold and interpolating therebetween to arrive at a lower threshold result; means for associating the lower threshold result with a lower systolic pressure; means for scanning the table from the maximum measured counter pressure towards larger corresponding cuff pressures and finding a first measured counter pressure less than the upper systolic threshold, a first measured counter pressure greater than the upper systolic threshold and interpolating therebetween to arrive at an upper threshold result; associating the upper threshold result with an upper systolic pressure; and means for averaging the upper and lower systolic pressure to arrive at a systolic pressure, whereby an accuratesystolic pressure is obtained from raw, unsmoothed measured counter pressure data, even including random respiration artifacts, without smoothing the raw data.