Pulse-wave-propagation-velocity-relating-information obtaining apparatus and blood-pressure-index measuring apparatus

• US 6,565,515 B2
• Filed: 01/22/2002
• Issued: 05/20/2003
• Est. Priority Date: 05/06/1999
• Status: Expired due to Term

• Current Assignee: Fukuda Denshi Company Limited
• Original Assignee: Colin Corporation (Fukuda Denshi Company Limited)
• Inventors: Ogura, Toshihiko
• Primary Examiner(s): Hindenburg, Max F.
• Assistant Examiner(s): Natnithithadha, Navin
• Application Number:
  US10/051,118
• Publication Number:
  US 20020091328A1
• Time in Patent Office: 483 Days
• Field of Search: 600/494, 600/492, 600/490, 600/493, 600/495, 600/496
• US Class Current: 600/494
• CPC Class Codes: A61B 5/02225 using the oscillometric method
• CPC Class Codes: A61B 5/0225 the pressure being controlled by electric signals, e.g. derived from Korotkoff sounds
• CPC Class Codes: A61B 5/0285 Measuring or recording phase velocity of blood waves

Abstract

An apparatus for obtaining information relating to a velocity at which a pulse wave propagates in a living subject, the apparatus including a first inflatable cuff and a second inflatable cuff which are adapted to be worn on two different portions of the subject, respectively, at least one cuff-pulse-wave detecting device which detects the pulse wave occurring to each of the first and second cuffs worn on the two different portions of the subject, and a velocity-relating-information obtaining device which obtains the information relating to the velocity, based on a time difference between a first time when the cuff-pulse-wave detecting device detects the pulse wave occurring to the first cuff, and a second time when the cuff-pulse-wave detecting device detects the pulse wave occurring to the second cuff.

Claims

1. An apparatus for obtaining information relating to a velocity at which a pulse wave propagates in a living subject, the apparatus comprising:

a first inflatable cuff and a second inflatable cuff which are adapted to be worn on two different portions of the subject, respectively;

at least one cuff-pulse-wave detecting device which detects the pulse wave occurring to each of the first and second cuffs worn on the two different portions of the subject; and

a velocity-relating-information obtaining device which obtains the information relating to the velocity, based on a time difference between a first time when the cuff-pulse-wave detecting device detects the pulse wave occurring to the first cuff, and a second time when the cuff-pulse-wave detecting device detects the pulse wave occurring to the second cuff.

2. An apparatus according to claim 1, further comprising a cuff-pressure holding device which holds a pressure in said each of the first and second cuffs, at a pre-set value lower than a diastolic blood pressure of the living subject, wherein the cuff-pulse-wave detecting device detects the pulse wave occurring to said each of the first and second cuffs worn on the two different portions of the subject, in a state in which the pressure in said each of the first and second cuffs is held at the pre-set value.

3. An apparatus according to claim 1, wherein the velocity-relating-information obtaining device comprises:

a velocity determining means for determining, according to a predetermined relationship, the velocity based on the time difference; and

a velocity correcting means for correcting the determined velocity, so that the corrected velocity corresponds to a reference blood pressure value.

4. An apparatus according to claim 1, wherein the first cuff is adapted to be worn on a superior limb of the living subject as one of the two different portions of the subject, and the second cuff is adapted to be worn on an inferior limb of the subject as the other of the two different portions.

5. An apparatus for measuring a blood-pressure index of a living subject, comprising:

a velocity-relating-information obtaining apparatus according to claim 4;

a first blood-pressure measuring device which measures a first blood pressure of the superior limb of the subject based on the pulse wave occurring to the first cuff;

a second blood-pressure measuring device which measures a second blood pressure of the inferior limb of the subject based on the pulse wave occurring to the second cuff; and

a blood-pressure-index determining means for determining the blood-pressure index, based on the first blood pressure measured by the first blood-pressure measuring device and the second blood pressure measured by the second blood-pressure measuring device.

6. An apparatus according to claim 5, further comprising a display device which simultaneously displays the blood-pressure index determined by the blood-pressure-index determining means and the velocity-relating information obtained by the velocity-relating-information obtaining means, so that the blood-pressure index and the velocity-relating information are comparable with each other by an observer.

7. An apparatus according to claim 6, wherein the display device comprises simultaneously displaying means for displaying, in a two-dimensional orthogonal coordinate system which is defined by a first axis representing blood-pressure index and a second axis representing velocity-relating information, a symbol at a set of coordinates corresponding to the blood-pressure index determined by the blood-pressure-index determining means and the velocity-relating information obtained by the velocity-relating-information obtaining means.

8. An apparatus according to claim 7, wherein the two-dimensional orthogonal coordinate system includes an abnormal area representing at least one of an abnormal blood-pressure index and an abnormal velocity-relating information.

9. An apparatus according to claim 7, wherein the first cuff is adapted to be worn on an upper arm of the subject and the first blood-pressure measuring device measures a blood pressure of the upper arm, wherein the second cuff is adapted to be worn on an ankle portion of the subject and the second blood-pressure measuring device measures a blood pressure of the ankle portion, and wherein the blood-pressure-index determining means determines the blood-pressure index based on the measured blood pressure of the upper arm and the measured blood pressure of the ankle portion.