Colin Electronics Co., Ltd.

Nippon Colin Co., Ltd.

Minoru Niwa

Chikao Harada

Hifumi Yokoe

Hiroshi Sakai

Noriyuki Kaida

Masanobu Yasui

Kimimasa Kurosawa

Tomoe Higuchi

An apparatus for detecting a pressure pulse wave produced from an artery of a living subject, including a first press member having a first press surface, a pressure sensing device supported by the first press surface, a second press member having a second press surface surrounding the first press surface, a pressing device pressing the first and second press members toward a body surface of the subject so that the first press surface is pressed against the artery via the body surface, the pressure sensing device generating an electric signal representing the pressure pulse wave produced from the artery and transmitted thereto via the body surface, the first and second press members being displaceable relative to each other in a direction in which the first and second press members are pressed by the pressing device, an actuating device displacing the first press member relative to the second press member so that the first press surface is advanced outward from the second press surface, and a determining device determining an optimum amount of the outward advance of the first press surface from the second press surface, by utilizing the electric signal generated from the pressure sensing device when the first press member is displaced outward from the second press member by the actuating device with the second press member being pressed on the body surface by the pressing device.

Pulse wave detecting apparatus

An apparatus for detecting a pulse wave produced from a subject in synchronous relationship with heartbeats of the subject, including a probe device for sensing a heartbeat synchronous pulse wave transmitted thereto and generating a signal representative of the sensed pulse wave, a sampling device for periodically determining a magnitude of the signal, a determining device for determining a lower peak and a following upper peak of the heartbeat synchronous pulse wave based on variation of the magnitudes determined by the sampling means, a calculating device for calculating a value by subtracting, from each of the magnitudes determined by the sampling means, a magnitude of the signal determined by the sampling means prior by a predetermined number of periods to the each of the magnitudes, and a judging means for judging whether or not the following upper peak is a proper upper peak of a pulse of the heartbeat synchronous pulse wave, based on the values calculated by the calculating means with respect to a portion of the signal between the lower peak and the following upper peak.

Heartbeat synchronous pulse wave detecting apparatus

Pulse wave detecting apparatus and pulse wave detecting method

An apparatus for detecting a heartbeat synchronous wave produced from a subject in synchronization with heartbeat of the subject, including a probe which is adapted to be set on a body portion of the subject, a sensor for detecting the heartbeat synchronous wave produced from the subject, the sensor being supported by the probe, a judging device for judging whether or not an electric knife is being used on the subject, and a device for, if the judging device judges that the electric knife is being used, ceasing from detecting the heartbeat synchronous wave, or discarding the heartbeat synchronous wave detected when the electric knife is being used. The judging device may be adapted to detect a high frequency electric current flowing from an electric knife to the probe via the body portion of the subject, and judge whether or not the electric knife is being used on the subject, based on the detected high frequency electric current.

Heartbeat synchronous wave detecting apparatus

A pulse wave detecting apparatus including a pulse wave sensor; a pressing device for pressing the sensor against an arterial vessel of a subject, while varying the pressing force; a first device for determining an amplitude of each of pulses of pulse wave which are detected by the sensor while the pressing force is varied; a second device for determining, based on the determined pulse amplitudes, a first range of the pressing force within which the pulse amplitudes are generally constant, the first range including a point at which a rate of change of the pulse amplitudes with respect to the pressing force is zero; a third device for determining a minimum value of each of the pulses detected by the sensor; a fourth device for determining, based on the determined pulse minimum magnitude, a second range of the pressing force within which the pulse minimum magnitudes are generally constant, the second range including a point at which a rate of change of the pulse minimum magnitudes with respect to the pressing force is minimum; a fifth device for determining an optimum range of the pressing force based on the first and second ranges, and determining an optimum value of the pressing force such that the optimum value falls within the optimum range; and a sixth device for adjusting the pressing device to the optimum pressing force, and obtaining a pulse wave of the subject through the sensor pressed with the optimum pressing force.

A pulse wave detecting apparatus including a sensing device sensing a pulse wave produced from an arterial vessel of a subject, a storing device concurrently storing the pulse wave signals generated by pressure sensing elements of the sensing device, a selecting device selecting, as an optimum pressure sensing element, one of the pressure sensing elements such that an amplitude of the pulse wave signal from the selected one element is the greatest of the amplitudes of the pulse wave signals stored in the storing means, a judging device judging whether or not the pulse wave signal from the selected one element is abnormal, and a changing device which, if an affirmative judgement is provided by the judging device, changes the optimum pressure sensing element from the selected one element to another of the pressure sensing elements such that an amplitude of the pulse wave signal from the selected another element is the greatest of the amplitudes of the pulse wave signals which are stored in the storing device concurrently with the abnormal pulse wave signal.

A reflectance pulse oximeter for detecting pulse synchronous waves is disclosed. The detector includes a sensor or sensors for detecting physical motion of the subject so that readings influenced by subject movement can be eliminated or indicated. One form of motion detector used is an accelerometer employing a spring-supported weight mounted within a cylinder. Accelerations beyond a predetermined value cause the weighted member to complete a circuit against the inside walls of the cylinder. Three accelerometers for detecting acceleration in each of three directions can be utilized. Motion can also be detected by a cubic motion detector having individual reed valves associated with each of six faces. A magnetic ball is movable in a spherical space formed within the cubic body. The magnetic ball operates to actuate only one of the reeds which is at a time. Motion detection can also be accomplished by a combination of the cubic motion detector and one or more accelerometers of the type previously described. A microprocessor control system determines the presence of a pulse synchronous wave from the reflectance detector system and can suppress indication of a pulse synchronous wave occurring simultaneously with motion detection by the motion detecting sensors, which motion is detected for greater than a predetermined period of time. The control system also can include provision for the display of an indication that the displayed pulse synchronous wave occurred during movement of the subject.

Pulse oximeter with physical motion sensor

An apparatus for continuously measuring blood pressure of a subject based on magnitude variation of heartbeat-synchronous pulses produced from the subject, the apparatus including a detecting device for continuously detecting the pulses, the detecting device including an inflatable cuff to be set around a body portion of the subject, magnitude of the pulses being varied as pressure in the inflatable cuff is varied, the varying magnitude of the pulses being detected by the detecting device, a selecting device for selecting a pulse from the pulses detected at a preceding blood pressure measuring cycle, the selected pulse corresponding to maximum blood pressure determined at the preceding measuring cycle, a first determining device for determining a reference value based on at least a magnitude of the selected pulse, a second determining device for comparing, with the reference value, the varying magnitude of the heartbeat-synchronous pulses detected at a current blood pressure measuring cycle, and determining as temporary maximum blood pressure a pressure in the inflatable cuff when the varying magnitude of the currently detected pulses exceeds the reference value, and a display device for displaying the temporary blood pressure before determination of maximum blood pressure at the current blood pressure measuring cycle.

Blood pressure measuring apparatus

An apparatus for detecting pressure pulse wave, including a main body having a pressing surface which is pressed against the body surface of a subject, and a plurality of through holes formed therethrough and opening in the pressing surface; a plate member secured to the pressing surface of the main body such that the plate member covers the openings of the through holes, the pressing plate having flexibility and including a plurality of displaceable portions each of which is aligned with the opening of a corresponding through hole; a plurality of optical fibers, one of opposite ends of each optical fiber being fitted in a corresponding through hole of the main body, such that an end face of the one end is opposed to a corresponding displaceable portion of the plate member at a predetermined distance therefrom; and a plurality of signal generating devices each of which is connected to the other of the opposite ends of a corresponding optical fiber, each signal generating device detecting the pressure pulse wave transmitted to a corresponding displaceable portion of the plate member, based on minute displacement of the corresponding displaceable portion which is optically detected through the corresponding optical fiber, and generating an electric signal representing the detected pressure pulse wave.

Pressure-pulse-wave detecting apparatus

A method and apparatus for measuring blood pressure of a subject based on Korotkoff sounds which are produced synchronously with heartbeat of the subject by pressing a body portion of the subject. The method including the steps of detecting the Korotkoff sounds by a microphone, the microphone generating electric signal corresponding to the detected Korotkoff sounds in a whole frequency range thereof; separating from the electric signal a signal component corresponding to the Korotkoff sounds in a comparatively high frequency range out of the whole frequency range; measuring, regarding the signal component, time of occurrence of at least one Korotkoff sound in the comparatively high frequency range; determining at least one time window regarding the electric signal, based on the time of occurrence measured regarding the signal component, the at least one time window consisting of a time interval smaller than a time period of occurrence of the Korotkoff sounds; and collecting a Korotkoff sound occurring in the time interval of each of the at least one time window determined regarding the electric signal, the collected Korotkoff sound being utilized for determining the blood pressure of the subject.

Method and apparatus for measuring blood pressure

A method and apparatus for monitoring blood pressure of a subject, the method including the steps of continuously detecting pulse wave which is produced from an artery synchronously with heartbeat of the subject; the pulse wave consisting of a plurality of pulses, repetitively measuring blood pressure of the subject, each of the repetitive blood pressure measurements being effected by inflating a cuff set on a body portion and deflating the cuff; repetitively determining a relationship between blood pressure and magnitude of pulse wave, based on each of the repetitively measured blood pressures and magnitude of at least one pulse of the pulse wave which pulse is detected during a predetermined time length including a first time length immediately before beginning of the inflation of the inflatable cuff for a corresponding one of the repetitive blood pressure measurements, and a second time length following the first time length; replacing each of the repetitively determined relationships, with another relationship determined following the each of the repetitively determined relationships; and continuously determining blood pressure of the subject based on magnitude of each of the pulses of the continuously detected pulse wave according to a currently effective one of the repetitively determined and replaced relationships.

Method and apparatus for monitoring blood pressure

A pulse wave detecting apparatus having a pulse wave sensor for detecting pulse wave produced from an arterial vessel of a subject, the pulse wave sensor being movable along a cross line crossing the arterial vessel so as to be positioned in place relative to the arterial vessel, and pressed against a body surface of the subject so as to detect the pulse wave produced from the arterial vessel, a frame member for being set on the body surface of the subject, a guide device supported by the frame member, for guiding the pulse wave sensor within a predetermined length along the cross line, a feeding screw supported by the frame member such that the feeding screw is rotatable about a longitudinal axis thereof parallel to the cross line, the feeding screw being threadedly engaged with the pulse wave sensor, a drive motor supported by the frame member such that the drive motor is located adjacent to the body surface when the frame member is set on the body surface of the subject, and a transmission device provided between the drive motor and the feeding screw, for transmitting rotating force of the drive motor to the feeding screw, so as to move the pulse wave sensor along the cross line.

An automatic blood pressure monitoring system includes a device which detects the degree of saturation of oxygen in the blood at a peripheral part of the body. The detecting device generates a signal if the degree of saturation is detected to be abnormal. A control device operates a blood pressure measuring device in response to the signal indicating abnormal oxygen saturation. In a second embodiment, a trigger device periodically generates a signal to operate the blood pressure measuring device. When an abnormal oxygen saturation is detected, a signal operates the blood pressure measuring device and the triggering interval is shortened.

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Nagoya, Japan

Minoru Niwa