Continuous blood-pressure monitoring apparatus
First Claim
1. An apparatus for continuously monitoring a blood pressure of a living subject, comprising:
- an inflatable cuff which is adapted to be wound around a portion of the subject;
a blood-pressure determining means for determining a blood pressure of the subject based on a signal obtained while a pressure in the cuff is changed;
a relationship determining means for determining a relationship between blood pressure and magnitude of pressure pulse wave, based on the blood pressure determined by the blood-pressure determining means and a magnitude of a first-artery pressure pulse wave detected from a first artery of the subject;
a blood-pressure monitoring means for iteratively determining, according to the thus determined relationship, a monitor blood-pressure value of the subject based on a magnitude of each of a plurality of heartbeat-synchronous pulses of the first-artery pressure pulse wave detected from the first artery;
a first pressure-pulse-wave sensor which is adapted to be worn on a portion of the subject that is distant from a chest of the subject, detects a second-artery pressure pulse wave that is produced by a second artery of said portion, and produces a pressure-pulse-wave signal representing the detected second-artery pressure pulse wave;
a heart-sound extracting means for extracting, from the pressure-pulse-wave signal produced by the pressure-pulse-wave sensor, a heart-sound component representing heart sounds generated by a heart of the subject;
a pulse-wave-propagation-velocity-related-information obtaining means for iteratively obtaining a piece of pulse-wave-propagation-velocity-related information which is related to a velocity at which the second-artery pressure pulse wave propagates through the second artery of the subject, based on a time of occurrence of a prescribed periodic point of a heartbeat-synchronous pulse of the heart-sound component extracted by the heart-sound extracting means and a time of occurrence of a prescribed periodic point of a corresponding heartbeat-synchronous pulse of the second-artery pressure pulse wave detected by the pressure-pulse-wave sensor;
a propagation-velocity-related-information-change-value determining means for periodically determining, at a prescribed judgment period, a change value of the pieces of pulse-wave-propagation-velocity-related information obtained by the pulse-wave-propagation-velocity-related-information obtaining means;
a monitor-blood-pressure-change-value determining means for periodically determining, at the judgment period, a change value of the monitor blood-pressure values determined by the blood-pressure monitoring means; and
a relationship checking means for comparing the change value of the pieces of pulse-wave-propagation-velocity-related information, determined by the propagation-velocity-related-information-change-value determining means, and the change value of the monitor blood-pressure values, determined by the monitor-blood-pressure-change-value determining means, with each other, and thereby judging whether the relationship between blood pressure and magnitude of pressure pulse wave, determined by the relationship determining means, is appropriate.
2 Assignments
0 Petitions
Accused Products
Abstract
An apparatus for continuously monitoring a blood pressure of a subject, comprising a cuff; a device for determining a blood pressure of the subject based on a signal obtained while the cuff pressure is changed; a device for determining a relationship between blood pressure and pressure pulse wave, based on a determined blood pressure and a detected magnitude of a first-artery pressure pulse wave; a device for iteratively determining, according to the relationship, a monitor blood pressure based on a magnitude of each pulse of the first-artery pressure pulse wave; a sensor which detects a second-artery pressure pulse wave from a second artery and produces a pressure-pulse-wave signal representing the second-artery pressure pulse wave; a device for extracting, from the pressure-pulse-wave signal, a heart-sound component representing heart sounds; a device for iteratively obtaining a piece of pulse-wave-propagation-velocity-related information, based on a time of occurrence of a periodic point of a pulse of the heart-sound component and a time of occurrence of a periodic point of a corresponding pulse of the second-artery pressure pulse wave; a device for periodically determining a change value of the pieces of information; a device for periodically determining a change value of the monitor blood-pressure values; and a device for comparing the change value of the pieces of information and the change value of the monitor blood-pressure values, with each other, and thereby judging whether the relationship is appropriate.
18 Citations
11 Claims
-
1. An apparatus for continuously monitoring a blood pressure of a living subject, comprising:
-
an inflatable cuff which is adapted to be wound around a portion of the subject;
a blood-pressure determining means for determining a blood pressure of the subject based on a signal obtained while a pressure in the cuff is changed;
a relationship determining means for determining a relationship between blood pressure and magnitude of pressure pulse wave, based on the blood pressure determined by the blood-pressure determining means and a magnitude of a first-artery pressure pulse wave detected from a first artery of the subject;
a blood-pressure monitoring means for iteratively determining, according to the thus determined relationship, a monitor blood-pressure value of the subject based on a magnitude of each of a plurality of heartbeat-synchronous pulses of the first-artery pressure pulse wave detected from the first artery;
a first pressure-pulse-wave sensor which is adapted to be worn on a portion of the subject that is distant from a chest of the subject, detects a second-artery pressure pulse wave that is produced by a second artery of said portion, and produces a pressure-pulse-wave signal representing the detected second-artery pressure pulse wave;
a heart-sound extracting means for extracting, from the pressure-pulse-wave signal produced by the pressure-pulse-wave sensor, a heart-sound component representing heart sounds generated by a heart of the subject;
a pulse-wave-propagation-velocity-related-information obtaining means for iteratively obtaining a piece of pulse-wave-propagation-velocity-related information which is related to a velocity at which the second-artery pressure pulse wave propagates through the second artery of the subject, based on a time of occurrence of a prescribed periodic point of a heartbeat-synchronous pulse of the heart-sound component extracted by the heart-sound extracting means and a time of occurrence of a prescribed periodic point of a corresponding heartbeat-synchronous pulse of the second-artery pressure pulse wave detected by the pressure-pulse-wave sensor;
a propagation-velocity-related-information-change-value determining means for periodically determining, at a prescribed judgment period, a change value of the pieces of pulse-wave-propagation-velocity-related information obtained by the pulse-wave-propagation-velocity-related-information obtaining means;
a monitor-blood-pressure-change-value determining means for periodically determining, at the judgment period, a change value of the monitor blood-pressure values determined by the blood-pressure monitoring means; and
a relationship checking means for comparing the change value of the pieces of pulse-wave-propagation-velocity-related information, determined by the propagation-velocity-related-information-change-value determining means, and the change value of the monitor blood-pressure values, determined by the monitor-blood-pressure-change-value determining means, with each other, and thereby judging whether the relationship between blood pressure and magnitude of pressure pulse wave, determined by the relationship determining means, is appropriate. - View Dependent Claims (2, 3, 4, 5, 6)
a pressure changing device which changes the pressure of the cuff, and a pressure sensor which detects the pressure of the cuff changed by the pressure changing device.
-
-
7. An apparatus for continuously monitoring a blood pressure of a living subject, comprising:
-
an inflatable cuff which is adapted to be wound around a portion of the subject;
a blood-pressure determining means for determining a blood pressure of the subject based on a signal obtained while a pressure in the cuff is changed;
a first relationship determining means for determining a relationship between blood pressure and magnitude of pressure pulse wave, based on the blood pressure determined by the blood-pressure determining means and a magnitude of a first-artery pressure pulse wave detected from a first artery of the subject;
a blood-pressure monitoring means for iteratively determining, according to the thus determined relationship, a monitor blood-pressure value of the subject based on a magnitude of each of a plurality of heartbeat-synchronous pulses of the first-artery pressure pulse wave detected from the first artery;
a first pressure-pulse-wave sensor which is adapted to be worn on a portion of the subject that is distant from a chest of the subject, detects a second-artery pressure pulse wave that is produced by a second artery of said portion, and produces a pressure-pulse-wave signal representing the detected second-artery pressure pulse wave;
a heart-sound extracting means for extracting, from the pressure-pulse-wave signal produced by the pressure-pulse-wave sensor, a heart-sound component representing heart sounds generated by a heart of the subject;
a standard-pulse-wave-propagation-velocity-related-information obtaining means for obtaining, as a standard piece of pulse-wave-propagation-velocity-related information, a piece of pulse-wave-propagation-velocity-related information which is related to a velocity at which the second-artery pressure pulse wave propagates through the second artery of the subject, based on a time of occurrence of a prescribed periodic point of a heartbeat-synchronous pulse of the heart-sound component in a first time duration comprising at least one of a first time period in which the pressure of the cuff is changed, a prescribed preceding time period preceding the first time period, and a prescribed following time period following the first time period, and a time of occurrence of a prescribed periodic point of a corresponding heartbeat-synchronous pulse of the second-artery pressure pulse wave in the first time duration;
a second relationship determining means for determining a second relationship between blood pressure and pulse-wave-propagation-velocity-related information, based on the blood pressure determined by the blood-pressure determining means and the standard piece of pulse-wave-propagation-velocity-related information obtained by the standard-pulse-wave-propagation-velocity-related-information obtaining means;
a judgment-pulse-wave-propagation-velocity-related-information obtaining means for obtaining, as a judgment piece of pulse-wave-propagation-velocity-related information, a piece of pulse-wave-propagation-velocity-related information which is related to the velocity at which the second-artery pulse wave propagates through the second artery of the subject, based on a time of occurrence of a prescribed periodic point of a heartbeat-synchronous pulse of the heart-sound component extracted by the heart-sound extracting means, and a time of occurrence of a prescribed periodic point of a corresponding heartbeat-synchronous pulse of the second-artery pressure pulse wave detected by the pressure-pulse-wave sensor, at a prescribed judgment period;
an estimated-blood-pressure determining means for determining, according to the second relationship, an estimated blood-pressure value of the subject based on the judgment piece of pulse-wave-propagation-velocity-related information obtained by the judgment-pulse-wave-propagation-velocity-related-information obtaining means; and
a relationship checking means for comparing, at the judgment period, the estimated blood-pressure value determined by the estimated-blood-pressure determining means, and a monitor blood-pressure value determined by the blood-pressure monitoring means based on a magnitude of a heartbeat-synchronous pulse of the first-artery pressure pulse wave detected at a time around a time when the judgment piece of pulse-wave-propagation-velocity-related information is obtained by the judgment-pulse-wave-propagation-velocity-related-information obtaining means, with each other, and thereby judging whether the relationship between blood pressure and magnitude of pressure pulse wave, determined by the first relationship determining means, is appropriate. - View Dependent Claims (8, 9, 10, 11)
-
Specification