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Peripheral blood-flow condition monitor

Assignee: Colin Medical Technology Corp
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Filing: 1996-08-12
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Granted: 1997-09-30
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Expires: 2016-08-12
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Abstract

Abstract An apparatus for monitoring a peripheral blood-flow condition of a living subject by detecting a peripheral blood-flow resistance of the subject, including a first and a second pulse-wave sensor which are adapted to be worn on a first and a second portion of the subject, respectively, to detect a first and a second pulse wave, respectively, each of which is produced in synchronism with a heartbeat of the subject, a phase-difference determining device for determining a difference of respective phases of the first and second pulse waves detected by the first and second pulse-wave sensors, and a peripheral blood-flow resistance determining device for determining the peripheral blood-flow resistance of the subject, based on the phase difference determined by the phase-difference determining device, according to a predetermined relationship between peripheral blood-flow resistance and phase difference.

Inventors

  • 👤 Masayuki Shinoda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 20:28
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/021; A61B5/02108; A61B5/02116; A61B5/022; A61B5/0225; A61B5/026; A61B5/0285; A61B5/02225

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 200 words
An apparatus for monitoring a peripheral blood-flow condition of a living subject by detecting a peripheral blood-flow resistance of the subject, comprising: a first and a second pulse-wave sensor which are adapted to be worn on a first and a second portion of the subject, respectively, to detect a first and a second pulse wave, respectively, each of which is produced in synchronism with a heartbeat of the subject; phase-difference determining means for determining a difference of respective phases of said first and second pulse waves detected by said first and second pulse-wave sensors; peripheral blood-flow resistance determining means for determining said peripheral blood-flow resistance of the subject, based on the phase difference determined by said phase-difference determining means, according to a predetermined relationship between peripheral blood-flow resistance and phase difference; and a blood pressure measuring device which measures a blood pressure of the subject, and wherein said peripheral blood-flow resistance determining means determines said peripheral blood-flow resistance of the subject, based on the phase difference determined by said phase-difference determining means and the blood pressure measured by said blood pressure measuring device, according to said predetermined relationship defined by a function of phase difference and blood pressure as variables.
Claim 2
Independent Claim 200 words
An apparatus for monitoring a peripheral blood-flow condition of a living subject by detecting a peripheral blood-flow resistance of the subject, comprising: a first and a second pulse-wave sensor which are adapted to be worn on a first and a second portion of the subject, respectively, to detect a first and a second pulse wave, respectively, each of which is produced in synchronism with a heartbeat of the subject; phase-difference determining means for determining a difference of respective phases of said first and second pulse waves detected by said first and second pulse-wave sensors; peripheral blood-flow resistance determining means for determining said peripheral blood-flow resistance of the subject, based on the phase difference determined by said phase-difference determining means, according to a predetermined relationship between peripheral blood-flow resistance and phase difference; and a blood pressure measuring device which measures a blood pressure of the subject, and wherein said peripheral blood-flow resistance determining means determines said peripheral blood-flow resistance of the subject, based on the phase difference determined by said phase-difference determining means and the blood pressure measured by said blood pressure measuring device, according to said predetermined relationship defined by a function of phase difference and blood pressure as variables.
Claim 3
Dependent Claim 114 words
An apparatus according to claim 1, wherein said blood pressure measuring device comprises an inflatable cuff adapted to be wound around a body portion of the subject, and measuring means for measuring said blood pressure of the subject by changing a pressure of said cuff applied to the body portion of the subject, and wherein said first pulse-wave sensor comprises said cuff, a pressure sensor which detects said pressure of the cuff, and a pulse-wave filter circuit which extracts, as said first pulse wave, an oscillatory pressure wave including a plurality of pulses produced in said cuff in synchronism with the heartbeat of the subject, from the cuff pressure detected by said pressure sensor.
Claim 4
Dependent Claim 76 words
An apparatus according to claim 2, further comprising a cuff-pressure regulating device which changes said pressure of said cuff to a predetermined value lower than a diastolic blood pressure of the subject and holds the cuff pressure at the predetermined value, and wherein said pulse-wave filter circuit extracts, as said first pulse wave, a plurality of heartbeat-synchronous pulses produced in said cuff held at said predetermined value, from the cuff pressure detected by said pressure sensor.
Claim 5
Dependent Claim 70 words
An apparatus according to claim 2, wherein said second pulse-wave sensor comprises a pressure pulse wave sensor which is adapted to be pressed against an artery of the subject via a skin of the subject, said pressure pulse wave sensor detecting, as said second pulse wave, a pressure pulse wave including a plurality of pulses produced from the artery of the subject in synchronism with the heartbeat of the subject.
Claim 6
Dependent Claim 81 words
An apparatus according to claim 1, further comprising index-value determining means for determining an index value indicative of a characteristic of a waveform of a decreasing portion of a heartbeat-synchronous pulse of said second pulse wave detected by said second pulse-wave sensor, wherein said peripheral blood-flow resistance determining means comprises correcting means for correcting, based on said index value determined by said index-value determining means, said peripheral blood-flow resistance determined based on said phase difference determined by said phase-difference determining means.
Claim 7
Dependent Claim 70 words
An apparatus according to claim 5, wherein said second pulse-wave sensor comprises a pressure pulse wave sensor which is adapted to be pressed against an artery of the subject via a skin of the subject, said pressure pulse wave sensor detecting, as said second pulse wave, a pressure pulse wave including a plurality of pulses produced from the artery of the subject in synchronism with the heartbeat of the subject.
Claim 8
Dependent Claim 36 words
An apparatus according to claim 1, further comprising a display device which displays, along a time axis, a time-wise trend of respective values of said peripheral blood-flow resistance determined by said peripheral blood-flow resistance determining means.
Claim 9
Dependent Claim 87 words
An apparatus according to claim 1, wherein said phase-difference determining means comprises means for determining a phase difference of each of heartbeat-synchronous pulses of said first pulse wave and a corresponding one of heartbeat-synchronous pulses of said second pulse wave, and wherein said peripheral blood-flow resistance determining means successively determines, according to said predetermined relationship, a peripheral blood-flow resistance of the subject, based on the phase difference of said each heartbeat-synchronous pulse of said first pulse wave and said corresponding heartbeat-synchronous pulse of said second pulse wave.
Claim 10
Independent Claim 205 words
An apparatus for monitoring a peripheral blood-flow condition of a living subject by detecting a peripheral blood-flow resistance of the subject, comprising: a first and a second pulse-wave sensor which are adapted to be worn on a first and a second portion of the subject, respectively, to detect a first and a second pulse wave, respectively, each of which is produced in synchronism with a heartbeat of the subject; phase-difference determining means for determining a difference of respective phases of said first and second pulse waves detected by said first and second pulse-wave sensors; peripheral blood-flow resistance determining means for determining said peripheral blood-flow resistance of the subject, based on the phase difference determined by said phase-difference determining means, according to a predetermined relationship between peripheral blood-flow resistance and phase difference; and index-value determining means for determining an index value indicative of a characteristic of a waveform of a decreasing portion of a heartbeat-synchronous pulse of said second pulse wave detected by said second pulse-wave sensor, wherein said peripheral blood-flow resistance determining means comprises correcting means for correcting, based on said index value determined by said index-value determining means, said peripheral blood-flow resistance determined based on said phase difference determined by said phase-difference determining means.
Claim 11
Independent Claim 205 words
An apparatus for monitoring a peripheral blood-flow condition of a living subject by detecting a peripheral blood-flow resistance of the subject, comprising: a first and a second pulse-wave sensor which are adapted to be worn on a first and a second portion of the subject, respectively, to detect a first and a second pulse wave, respectively, each of which is produced in synchronism with a heartbeat of the subject; phase-difference determining means for determining a difference of respective phases of said first and second pulse waves detected by said first and second pulse-wave sensors; peripheral blood-flow resistance determining means for determining said peripheral blood-flow resistance of the subject, based on the phase difference determined by said phase-difference determining means, according to a predetermined relationship between peripheral blood-flow resistance and phase difference; and index-value determining means for determining an index value indicative of a characteristic of a waveform of a decreasing portion of a heartbeat-synchronous pulse of said second pulse wave detected by said second pulse-wave sensor, wherein said peripheral blood-flow resistance determining means comprises correcting means for correcting, based on said index value determined by said index-value determining means, said peripheral blood-flow resistance determined based on said phase difference determined by said phase-difference determining means.
Claim 12
Dependent Claim 68 words
An apparatus according to claim 9, wherein said second pulse-wave sensor comprises a pressure pulse wave sensor adapted to be pressed against an artery of the subject via a skin of the subject, said pressure pulse wave sensor detecting, as said second pulse wave, a pressure pulse wave including a plurality of pulses produced from the artery of the subject in synchronism with the heartbeat of the subject.
Claim 13
Dependent Claim 43 words
An apparatus according to claim 9, further comprising a display device which displays, along a time axis, a time-wise trend of respective corrected values of said peripheral blood-flow resistance which are provided by said correcting means of said peripheral blood-flow resistance determining means.
Claim 14
Dependent Claim 89 words
An apparatus according to claim 9, wherein said phase-difference determining means comprises means for determining a phase difference of each of heartbeat-synchronous pulses of said first pulse wave and a corresponding one of heartbeat-synchronous pulses of said second pulse wave, and wherein said peripheral blood-flow resistance determining means comprises means for determining, according to said predetermined relationship, a peripheral blood-flow resistance of the subject, based on the phase difference of said each heartbeat-synchronous pulse of said first pulse wave and said corresponding heartbeat-synchronous pulse of said second pulse wave.

References Cited (Backward Citations)

JPS61119239A Cited
EP0330463A1 Cited
US5103831A Cited
EP0487726A1 Cited
US5293874A Cited
US5101828A Cited
US5279303A Cited
US5289823A Cited
WO1996022050A1 Cited
EP0750878A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-09-29 2001-03-31 2001-09-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-09-29 2005-03-31 2005-09-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-09-29 2009-03-31 2009-09-30 $7700.00 Window Closed / Lapsed

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