JP2010264126A - Biological information measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a biological information measuring device, capable of recognizing whether or not the device has normally operated without need of continuously watching biological information on display. <P>SOLUTION: The biological information measuring device includes measuring parts to respectively emit a plurality of lights of different wavelengths to a biological tissue, and receive the respective lights transmitted through or reflected on the biological tissue, an analysis processing part to compute the biological information of the biological tissue based on the respective lights transmitted through or reflected on the biological tissue, a display part to display the biological information computed by the analysis processing part, and a determination part to determine whether or not measurement to the biological tissue by the measuring parts is completed. The display part displays the biological information to be fixed in a case where it is determined that the measurement to the biological tissue by the measuring parts is completed, and it also displays normal operation information to show that it has normally operated in a case where it has normally operated from measurement to the biological tissue by the measuring parts till fixed display by the display part. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a biological information measuring device.

  A biological information measuring device that continuously measures biological information in a non-invasive manner is known. The principle of this biological information measuring device is as follows. The light transmitted or reflected through the living tissue periodically pulsates due to the periodic contraction of arterial blood in the living tissue. The fluctuation of the pulsating light reflects the light absorption characteristics of arterial blood. Therefore, the biological information can be obtained based on the signal component corresponding to the fluctuation of the light obtained by irradiating the biological tissue with light of a specific wavelength and receiving the light transmitted or reflected through the biological tissue. .

As biological information measured by such a biological information measuring device, for example, arterial blood oxygen saturation SpO ₂ , pulse number (BPM), perfusion index (PI), pulse waveform, etc. is there.

  Among biological information, a biological information measuring device that measures the oxygen saturation of arterial blood in particular is called a pulse oximeter. The use of pulse oximeters is not limited to wards such as operating rooms and intensive care units. And its use is expanding to sports fields such as mountain climbing.

  Examples of such a biological information measuring device include Patent Documents 1, 2, and 3 (Patent Document 1 is a publication of Japanese Patent Application 2).

  The pulse oximeters disclosed in Patent Documents 1 and 2 compare the light measurement value measured by the photodetector provided in the finger clip with the maximum measurement reference level stored in advance, and the light measurement value is If it is larger, the finger clip type pulse oximeter determines that the finger has been removed from the finger clip, automatically stops the measurement, and returns to the low power mode.

  Further, the oximeter disclosed in Patent Document 3 obtains the stability of the arterial oxygen saturation from the arterial oxygen saturation displayed as needed, and determines that the arterial oxygen saturation is stable. Without performing the subsequent measurement, the arterial blood oxygen saturation displayed at that time is continuously displayed (fixed display).

Japanese National Patent Publication No. 10-502268 International Publication No. 96/00518 Pamphlet Japanese Patent Publication No. 7-32767

  By the way, in the finger clip type pulse oximeter disclosed in Patent Documents 1 and 2, when the person to be measured removes the finger from the finger clip, the mode returns to the low power mode. Therefore, when the person to be measured removes his / her finger from the finger clip and holds the finger clip-type pulse oximeter to the measurer, the measurer determines whether the finger clip-type pulse oximeter is operating normally. May not be confirmed.

  Further, in the oximeter disclosed in Patent Document 3, since the arterial blood oxygen saturation degree determined to be stable is continuously displayed (fixed display), whether the display is fixed due to the failure of the oximeter or whether the oximeter is normal There is a possibility that it cannot be confirmed whether it is in a fixed display.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a biological information measuring apparatus capable of notifying whether or not the biological information measuring apparatus has been normally operated.

As a result of various studies, the present inventor has found that the above object is achieved by the present invention described below. That is, in the biological information measuring apparatus according to the present invention, a plurality of lights having different wavelengths are emitted to the biological tissue, and a measuring unit that receives each light transmitted or reflected through the biological tissue, and the biological tissue is transmitted. Or, based on each reflected light, the analysis processing unit that calculates biological information of the biological tissue, the display unit that displays the biological information calculated by the analysis processing unit, and the measurement of the biological tissue by the measurement unit is completed. A determination unit that determines whether or not the measurement is performed, and when the determination unit determines that the measurement of the biological tissue by the measurement unit is completed, the display unit displays the biological information as a fixed display, When operating normally from the measurement of the biological tissue in the measurement unit to the fixed display of the display unit, normal operation information indicating that the operation was normal is further displayed. That.
The fixed display means that the currently displayed value is continuously displayed as it is.

  According to this configuration, it is possible to confirm whether or not the biological information that is fixedly displayed is a value that is displayed when the biological information measuring device operates normally. For this reason, it is not necessary to monitor the biological information being measured in order to confirm whether or not the biological information measuring device is operating normally.

  Further, in the above-described biological information measuring device, the measurement unit is detachably attached to the biological tissue, and the determination unit detects whether the measurement unit is attached to the biological tissue during measurement. When it is detected that the measurement unit is removed from the biological tissue, it is determined that the measurement of the biological tissue by the measurement unit is completed.

  According to this configuration, since the measuring unit does not consume useless power, power is saved.

  In the above-described biological information measuring device, the calculation unit further determines the stability of the biological information, and the display unit further displays the stability.

  According to this configuration, the degree of stability of the displayed biological information is displayed. For this reason, the measurer can take measures such as extending the measurement time and performing re-measurement according to a decrease in stability or the like.

  Moreover, the above-described biological information measuring device further includes a notification unit that notifies the normal operation information with sound.

  According to this configuration, it is possible to confirm by sound whether or not the biological information fixedly displayed is a value displayed when the biological information measuring device operates normally. For this reason, it is not necessary to monitor the biological information being measured in order to confirm whether or not the biological information measuring device has been normally operated.

  Moreover, in the above-described biological information measuring apparatus, the biological information is arterial oxygen saturation.

  According to this configuration, the arterial oxygen saturation can be measured.

  According to the present invention, it is possible to provide a biological information measuring device capable of recognizing whether or not the device has been normally operated without continuously viewing the displayed biological information.

It is a figure which shows the electrical structure of the biological information measuring device in embodiment. It is a figure which shows the external appearance structure of the biometric information measuring apparatus in embodiment. It is a flowchart which shows operation | movement in the case of displaying normal measurement completion in a display part in embodiment. It is a figure for demonstrating the display of the display part in embodiment. (A) is a display on the display unit during measurement, and (b) is a display on the display unit during normal operation information display.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.

(Configuration of the embodiment)
FIG. 1 is a diagram illustrating an electrical configuration of a biological information measuring apparatus according to an embodiment. FIG. 2 is a diagram illustrating an external configuration of the biological information measurement device according to the embodiment.

  The biological information measuring apparatus M in the present embodiment emits a plurality of lights having different wavelengths to the living tissue, and receives a light transmitted through or reflected by the living tissue, and transmits or passes through the living tissue. Based on each reflected light, the analysis processing unit that calculates biological information of the biological tissue, the display unit that displays the biological information calculated by the analysis processing unit, and the measurement of the biological tissue by the measurement unit are completed. A determination unit that determines whether or not the display unit is configured to display the biological information as a fixed display when the determination unit determines that the measurement of the biological tissue by the measurement unit is completed. In the case of normal operation from the measurement of the biological tissue in the unit to the fixed display of the display unit, normal operation information indicating that the operation was normal is further displayed.

  More specifically, the biological information measuring apparatus M includes an apparatus main body 1 and a measuring unit 2 as shown in FIG.

The measurement unit 2 is measured at a predetermined time interval necessary for analysis processing of biological information in the apparatus main body 1, acquires time series data related to the pulsation of the biological body, and this time series data is an I / V conversion unit described later 31 is output as a current signal. Here, as a method for detecting pulsation, various methods can be adopted. For example, a method using the light absorption characteristic of hemoglobin in a living tissue can be preferably employed. As is well known, oxygen is carried by hemoglobin to each cell in the living body, but hemoglobin combines with oxygen in the lung to become oxygenated hemoglobin, and returns to hemoglobin when oxygen is consumed by cells in the living body. Oxygen saturation refers to the proportion of oxygenated hemoglobin in the blood. The absorbance of these hemoglobins and the absorbance of oxyhemoglobin are wavelength dependent.For example, hemoglobin absorbs more light than oxyhemoglobin for red light in the red region, but has a wavelength in the infrared region. Infrared light absorbs less light than oxyhemoglobin. This method obtains biological information such as arterial oxygen saturation SpO ₂ , pulse rate, and perfusion index by utilizing the difference in absorption characteristics of hemoglobin and oxyhemoglobin with respect to red light and infrared light. Is.

  The measurement unit 2 includes, for example, a light-emitting element that includes a light-emitting element that irradiates a predetermined biological tissue with red light, and a light-receiving element that receives light that is irradiated with the light-emitting element and transmits or reflects the biological tissue to be measured A first light-emitting element, a light-emitting element that irradiates the predetermined biological tissue with infrared light, and a light-receiving element that receives each light that is irradiated with the light-emitting element and transmitted or reflected through the biological tissue to be measured A reflective or transmissive sensor including a second element. The measuring unit 2 having such a configuration is mounted on a predetermined living tissue, monitors each received light amount by the first element and the second element, and each received light is converted into an electric signal according to the light intensity. By performing photoelectric conversion, each of the time series data related to the pulsating living tissue is measured. In addition, the measurement unit 2 may be a device that includes a pressure sensor or the like and acquires pulse wave data as the time-series data by directly detecting a pulse pressure due to a blood vessel pulsation. The measurement unit 2 is connected to the apparatus main body 1 and outputs each time series data to an I / V conversion unit 31 described later. For example, the measurement unit 2 includes a light emitting unit 21 and a light receiving unit 22 as shown in FIG.

  When the measurement unit 2 is a transmissive sensor, the light emitting unit 21 and the light receiving unit 22 are arranged, for example, such that the light emitting unit 21 and the light receiving unit 22 face each other with a living tissue therebetween. . The light emitted from the light emitting unit 21 passes through the living tissue and is received by the light receiving unit 22. Thereby, biological information can be measured based on the transmitted light of the measurement site.

  When the measurement unit 2 is a reflective sensor, the light emitting unit 21 and the light receiving unit 22 are, for example, arranged adjacent to a living tissue. The light emitted from the light emitting unit 21 is reflected in the living tissue and received by the light receiving unit 22. Thereby, biological information can be measured based on the reflected light of a measurement part.

  The light emitting unit 21 is an infrared light source including a red light source that emits red light having a wavelength in the red region and a light source that emits infrared light having a wavelength in the infrared region on a biological tissue, Connected to the control unit 4 and controlled to be turned on and off by the measurement control unit 4. The light emitting unit 21 performs measurement so that an appropriate level of output can be obtained even if an individual difference in biological tissue (for example, the thickness of a fingertip) serving as a measurement site or a secular change in the light receiving sensitivity of the light receiving unit 22 occurs. It is preferable that the amount of irradiation light can be adjusted within a certain range. The light emitting unit 21 is, for example, a light emitting diode that emits red light and a light emitting diode that emits infrared light.

  The light receiving unit 22 receives light from the light emitting unit 21 that has been transmitted or reflected through the living tissue, generates a current having a magnitude corresponding to the intensity of the received light, and outputs the current to the I / V conversion unit 31 described later. More specifically, the light receiving unit 22 converts optical signals of red light and infrared light into electrical signals that are biological information signals, and outputs them to an I / V conversion unit 31 described later. The light receiving unit 22 is, for example, a photoelectric conversion element such as a silicon photodiode having sensitivity to red light and infrared light emitted from the light emitting unit 21.

  The apparatus main body 1 includes a control unit 4, a storage unit 5, a display unit 6, a notification unit 7, a power supply unit 8, an I / V conversion unit 31, and an A / D conversion unit 32. The

The storage unit 5 includes a memory such as a ROM (Read Only Memory) and a RAM (Random Access Memory) that stores a control program of the biological information measuring apparatus M. In the storage unit 5, a reference value serving as a reference for determining whether or not the measurement by the determination unit 43 is completed, and a biological information signal obtained by the measurement unit 2 are analyzed by the analysis processing unit 42. (For example, the light amount and pulse wave amplitude of each light received by the light receiving unit 22, the amplitude ratio of infrared light and red light, the instantaneous SpO ₂ value, the display SpO ₂ value, and the like) are stored.

The determination of the stability of the SpO ₂ value uses data based on the measurement results going back to the past for a certain period from the present time. Therefore, the storage unit 5 includes the values obtained by the analysis processing in the analysis processing unit 42. You may store only the data by the measurement result which goes back from the present time to the past for a fixed period. By storing in this way, the memory | storage part 5 can suppress the memory consumption of the data by a measurement result. This storage method is, for example, FIFO (First In, First Out).

Further, the storage unit 5 converts the value obtained by the analysis processing in the analysis processing unit 42 into time measurement information such as a measurement time output by a time measuring unit (not shown) having a timer function provided in the CPU. It may be stored in association. The determination of the stability of the SpO ₂ value uses not only the current measurement result but also the data based on the measurement result that goes back in the past for a certain period of time. Can be easily read out. Note that the time measurement information may be time from the start of measurement or time.

  The display unit 6 is controlled by the display control unit 44 and displays biological information calculated by the analysis processing unit 42 and normal operation information indicating that when the measurement unit 2 and the apparatus main body 1 operate normally. . The display unit 6 is, for example, a display device such as a color liquid crystal display (LCD), a 7-segment LED (Light Emitting Diode), or an organic photoluminescence display. The display unit 6 displays various measurement information such as data analysis results of pulse wave data in an arbitrary form such as light lighting (including turning on and off, blinking), sentences, numbers, pictograms, and display by color. To do.

  The notification unit 7 notifies the person to be measured with light, sound, vibration, or the like that a predetermined time has elapsed since the start of measurement, that the display of the measurement value is fixed display, and that the measurement has been normally completed. The notification unit 7 is, for example, an alarm that outputs an alarm sound or sound, a vibration device, or an LED that lights or flashes.

  The power supply unit 8 supplies power to the biological information measurement device M, that is, the measurement unit 2 and the device main body 1. The power supply unit 8 is, for example, a button battery or a secondary battery. Note that the power supply unit 8 may include a power supply circuit having a power-off function that automatically stops power supply when the fixed display continues for a certain period of time.

  The operation unit 9 is a device for turning on / off each unit of the biological information measuring apparatus M. The operation unit 9 is, for example, a switch for turning on / off the power, a switch for turning off the fixed display of the display unit 6, a switch for instructing measurement start, and other various operations. By providing such an operation unit 9, the biological information measuring device M can be expected to have a further power saving effect.

  The I / V conversion unit 31 converts the current signal output from the light receiving unit 22 into a voltage signal at a predetermined cycle, and outputs this voltage signal to the A / D conversion unit 32 as a photoelectric pulse wave signal.

  The A / D conversion unit 32 converts the photoelectric pulse wave signal, which is an analog biological information signal output from the I / V conversion unit 31, into a digital photoelectric pulse wave signal and outputs it to the control unit 4.

  The control unit 4 controls the operation of each unit of the biological information measuring device M. The control unit 4 includes, for example, various electronic components, integrated circuit components, a CPU (Central Processing Unit), and the like. The control unit 4 is functionally configured to include a measurement control unit 41, an analysis processing unit 42, a determination unit 43, and a display control unit 44.

  The measurement control unit 41 controls the measurement operation of biological information by the measurement unit 2 according to a predetermined measurement program. Specifically, the measurement control unit 41 alternately emits red light and infrared light from the light emitting unit 21 at each sampling period, and acquires a photoelectric conversion signal from the light receiving unit 22 in synchronization with the light emission timing. To do. When the determination unit 43 detects (determines) that the measurement unit 2 has been removed from the living tissue, the measurement control unit 41 ends the measurement operation of the measurement unit 2.

The display control unit 44 controls the display operation of the display unit 6 and the notification operation of the notification unit 7. Specifically, the display control unit 44 displays a display indicating the state under measurement or an SpO ₂ value calculated by analyzing the biological information signal obtained by the measurement by the analysis processing unit 42 in a predetermined display form. The display operation to be displayed on the display unit 6 is controlled. In addition, when the determination unit 43 determines that the measurement is finished, the measurement control unit 41 displays the currently displayed SpO ₂ value in a fixed manner. If the operation from measurement to fixed display is normal, the measurement control unit 41 is normal. The display unit 6 is controlled so that the display unit 6 displays the operation information. Further, when the display unit 6 uses the SpO ₂ value as a fixed display, the display unit 6 is controlled to display that the display is a fixed display and the degree of stability at that time. The degree of stability includes a maximum value, a minimum value, an average value, and the like during the determination target period, and the display control unit 44 controls the display unit 6 to display them. Note that at least one of the maximum value, the minimum value, and the average value may be displayed.

The analysis processing unit 42 performs predetermined data analysis based on the biological information signal obtained by the measurement unit 2, and the light amount and pulse wave amplitude of each light received by the light receiving unit 22, the infrared light and the red light. An amplitude ratio, an instantaneous SpO ₂ value, a display SpO ₂ value, a stability determination value, a pulse rate, a perfusion index, and the like are obtained.

The instantaneous SpO ₂ value is calculated by a known method from the amplitude ratio of red light and infrared light for each sampling period.

The displayed SpO ₂ value is an average value or a moving average value of the calculated instantaneous SpO ₂ values in a predetermined range (for example, 12 seconds). The display SpO ₂ value is displayed on the display unit 6 by the display control unit 44.

  The stability is an index for determining the degree of fluctuation of the value of the biological information obtained by the analysis processing unit 42. For example, when noise due to body motion is superimposed on the photoelectric pulse wave signal, the time-series data of the biological information varies depending on the condition of the measurement subject (for example, low perfusion), the measurement site, etc., and correct biological information is measured. I can't. Therefore, the high degree of stability of the biological information is detected by obtaining the stability and comparing the predetermined value with the stability.

The stability calculation is as follows. The stability of the SpO ₂ value after the measurement is completed and the degree of stability when the measurement is stable are calculated. For example, the stability determination may be performed using the following formula 1. In Equation 1, DS is a determination value, and W (I) is a weighting factor. S (0) represents the currently displayed SpO ₂ value, S (-1) represents the previous SpO ₂ value, and S (-2) displayed the previous two. It represents the SpO ₂ value. W (I) is a value determined by I.

DS is a calculated display SpO ₂ values, are multiplied by W (I) to the difference between calculated display SpO ₂ values prior one, the latest calculated value (current display SpO ₂ value) To the display SpO ₂ value calculated before 5 points. That is, in order to obtain DS, six points of display SpO ₂ values are required. Therefore, DS is a measure of the most recent variation in the display SpO ₂ value. Not only latest display SpO ₂ values, for display SpO ₂ values in a past measurement, because it is stored in the storage unit 5 in association with the time information, the analysis processing unit 42 can be easily read.

The determination value DS obtained by Equation 1 indicates that the smaller the value is, the less variation in the displayed SpO ₂ value is, and the higher the stability is. If the determination value DS is equal to or less than a predetermined threshold, it is determined that the SpO ₂ value is stable.

Specifically, the analysis processing unit 42 may obtain DS by substituting the display SpO ₂ value into Equation 1 and determine the stability. Here, W (I) in Equation 1 is a weighting factor, which can be arbitrarily determined. In Formula 1, since the stability at the present time is determined, when the display SpO ₂ value calculated in the past is used, that is, as the value of I is smaller, the value of W (I) may be decreased. . In some cases, W (I) may be a fixed value.

The analysis processing unit 42 sets a predetermined threshold in the DS obtained by Equation 1, and determines that the DS is stable when the DS is equal to or less than the threshold. Note that the smaller the DS, the higher the stability because it can be said that there is less immediate variation in the display SpO ₂ value. Therefore, the degree of stability can be determined from the value of DS. Specifically, since 0 is the minimum value for the DS value, the range from 0 to the threshold value may be further divided into 10 equal parts, and the degree of stability may be determined in 10 steps based on each value. For example, when the predetermined threshold is Th, the threshold at each stage is represented by B (i). Note that i is an integer of 0 to 9, and the larger i is, the larger B (i) is. For example, B (0) = Th / 10, B (1) = (Th / 10) × 2 = Th / 5, B (2) = (Th / 10) × 3, B (3) = (Th / 10) ) × 4 = Th × 2/5, B (4) = (Th / 10) × 5 = Th / 2, B (5) = (Th / 10) × 6− = Th × 3/5, B (6 ) = (Th / 10) × 7, B (7) = (Th / 10) × 8 = Th × 4/5, B (8) = (Th / 10) × 9, B (9) = (Th / 10) × 10 = Th. If DS is 0 or more and B (0) or less, the stability is 10, and if DS is greater than B (0) and less than or equal to B (1), the stability is 9 and DS is greater than B (1) and B ( 2) Stability is 8 if DS or less, stability is 7 if DS is greater than B (2) and B (3) or less, and stability is DS if DS is greater than B (3) and B (4) or less 6. Stability is 5 if DS is greater than B (4) and less than B (5), stability is 4 if DS is greater than B (5) and less than B (6), DS is B (6) Greater than B (7), the stability is 3, and if DS is greater than B (7) and less than B (8), the stability is 2, and DS is greater than B (8) and less than B (9). If so, the degree of stability may be determined with a stability of 1. Note that the degree of stability is not limited to 10 levels, and the set level may be increased or decreased as appropriate. Further, in the above description, the threshold intervals in each stage represented by B (i) are set to be equal intervals, but they may be changed according to the stages instead of being equal intervals. For example, by increasing the threshold interval as i increases, the degree of stability is determined more severely as the stability increases.

Note that the determination of whether or not it is stable and the determination of the degree of stability are not limited to the method according to Equation 1 as described above, and other methods may be used. For example, in addition to the determination using the display SpO ₂ value, the light amount and pulse wave amplitude of each light received by the light receiving unit 22, the amplitude ratio between infrared light and red light, the 1 second SpO ₂ value, and the instantaneous SpO _{2 The} stability may be determined by combining any or all of these data including binary values or the display SpO ₂ values. These past data are also stored in the storage unit 5. For example, the stability of the SpO ₂ value may be determined from the variation or average value of these data, and the degree of stability may be determined based on the stability. Specifically, the analysis processing unit 42 calculates the minimum value and the maximum value among the respective data in the determination target period, and determines that the data is stable if the difference between the minimum value and the maximum value is equal to or less than a predetermined value. Alternatively, the degree of stability may be determined according to the magnitude of this difference. In the determination of the stability, the current value obtained by the latest measurement and the value obtained by the past measurement are used, and the period in which the values used for the determination are measured is referred to as a determination target period.

  Instead of the above-described stability, the analysis processing unit 42 may use an average value for each determination target period obtained while shifting the determination target period. The analysis processing unit 42 compares the average value for each determination target period, and determines that the biological information is stable if the variation in the average value is equal to or less than a predetermined value. In addition, the degree of stability may be determined according to the size of the variation.

  Furthermore, instead of the above-described stability, the analysis processing unit 42 may use the signal level of the light amount of each light or the signal level of the pulse wave amplitude. The higher the signal level, the better the signal-to-noise ratio (SN ratio). Therefore, when the signal level is high, it is determined that the stability is high, and the degree of stability is determined.

  The perfusion index is a percentage of the direct current component AC with respect to the alternating current signal DC of the photoelectric pulse wave signal of infrared light (PI (%) = AC / DC × 100), and the living tissue serving as the measurement site It is an index that relatively represents the intensity of the pulse wave. When the measurement unit 2 is attached to a living tissue, the measurement accuracy during body movement is improved by attaching the measurement unit 2 to a region where the PI is highest.

  The pulse wave number is a pulse number per minute, and is given by a frequency that gives a Fourier transform of the photoelectric pulse wave signal or a peak of its absolute value.

  The determination unit 43 determines whether or not the measurement unit 2 has finished the measurement. Specifically, the determination unit 43 determines that the measurement is completed when the measurement unit 2 is detached from the biological tissue while the measurement unit 2 is attached to the biological tissue. As a method for detecting (determining) whether or not the measurement unit 2 is attached to the living tissue during measurement, various methods can be employed. For example, light received by the light receiving unit 22 is used. Can do. Accordingly, it is possible to reduce the size and cost without requiring a separate member for determining the end of measurement.

  The light received by the light receiving unit 22 varies greatly depending on whether or not the living tissue is attached to the measuring unit 2. Thereby, the determination part 43 determines whether the measurement part 2 is mounted | worn with the biological tissue.

  In a state where the measurement unit 2 is attached to the living tissue, the light receiving unit 22 receives infrared light and red light transmitted or reflected through the living tissue. In a state where the measurement unit 2 is removed from the biological tissue, the measurement unit 2 is compared with light received by the light receiving unit 22 when the measurement unit 2 is attached to the biological tissue, for example, as described later. If the sensor is a transmissive sensor, the light received by the light receiving unit 22 is increased. If the measuring unit 2 is a reflective sensor, the light received by the light receiving unit 22 is reduced (assuming that there is no external light).

  In the case where the measurement unit 2 is a transmissive sensor and the measurement unit 2 is detached from the living tissue, the light emitted from the light emitting unit 21 reaches the light receiving unit 22 with almost the same intensity and hardly changes with time. Therefore, the light received by the light receiving unit 22 is equal to or greater than the saturation signal amount that is the maximum signal amount that can be received by the light receiving unit 22. The light receiving unit 22 outputs the current obtained by converting the saturation signal amount to the control unit 4 as a photoelectric pulse wave signal via the I / V conversion unit 31 and the A / D conversion unit 32. Here, the photoelectric pulse wave signal is a maximum value because it is obtained by converting the saturation signal amount. When the reference value (maximum value of the photoelectric pulse wave signal) stored in advance in the storage unit 5 and the photoelectric pulse wave signal input to the control unit 4 are substantially equal to each other for a predetermined time, the determination unit 43 When the measurement unit 2 is deviated from the control unit 4 and the photoelectric pulse wave signal input to the control unit 4 is smaller than the reference value (maximum value of the photoelectric pulse wave signal) stored in the storage unit 5 in advance, the living tissue It is determined that the measurement unit 2 is attached to the. Thus, the determination unit 43 compares the reference value (maximum value of the photoelectric pulse wave signal) stored in advance in the storage unit 5 with the input photoelectric pulse wave signal, and the measurement unit 2 is attached to the living tissue. It is determined whether or not it has been done.

  In the case where the measurement unit 2 is a reflective sensor and the measurement unit 2 is detached from the living tissue, the light irradiated by the light emitting unit 21 is not reflected by the living tissue, and thus the light receiving unit disposed adjacent to the light emitting unit 21. Do not reach 22. Accordingly, the output of the light receiving unit 22 is a value close to 0 (hereinafter, the minimum value). When the photoelectric pulse wave signal input to the control unit 4 is lower than the reference value (minimum value of the photoelectric pulse wave signal) stored in the storage unit 5 in advance, the determination unit 43 determines that the measurement unit 2 from the living tissue On the other hand, when the photoelectric pulse wave signal input to the control unit 4 is larger than the minimum value of the photoelectric pulse wave signal stored in advance in the storage unit 5, the measurement unit 2 is attached to the living tissue. Is determined. Thus, the determination unit 43 compares the reference value (minimum value of the photoelectric pulse wave signal) stored in advance in the storage unit 5 with the input photoelectric pulse wave signal, and the measurement unit 2 is attached to the living tissue. It is determined whether or not it has been done.

  The biological information measuring device M is provided in combination with an exterior member as appropriate. The shapes of the measurement unit 2, the apparatus main body 1, and the exterior member can take various forms in consideration of the ease of attachment to the living body and the visibility of the display unit 6 and the notification unit 7.

  The exterior member protects the measurement unit 2 and the apparatus main body 1 from external force and external light, and at the same time, prevents the external force and external light from affecting the biological information. The exterior member is, for example, a waterproof member or a light shielding member. The form of the exterior member is not particularly limited. For example, the exterior member can be configured as a housing or the like on which the apparatus main body 1 and the measurement unit 2 are mounted. For the arrangement of the measurement unit 2 in the exterior member, either a transmission type sensor or a reflection type sensor is employed. The measurement unit 2 and the exterior member may be separated or movable. As described above, the outer shape of the exterior member is set to an appropriate shape according to the attachment site to the living body and the form of the measurement unit 2. For example, as shown in FIG. 2, the exterior member includes a first exterior member 101 and a second exterior member 102 connected by a hinge 103.

  For example, as shown in FIG. 2, the first exterior member 101 is a casing in which the apparatus main body 1 is mounted. A display portion 6 is disposed on one side surface of the casing so that the display surface faces the outside, and an abdominal piece that fits the fingertip abdomen of the measurement subject's finger 300 is formed on the upper surface thereof. ing.

  For example, as shown in FIG. 2, the second exterior member 102 is a substantially rectangular parallelepiped on which the measurement unit 2 is mounted. A back piece that fits the fingertip back of the finger 300 to be measured is formed on the bottom surface of the substantially rectangular parallelepiped facing the abdomen piece of the first exterior member 101.

  The hinge 103 connects one end of the abdomen piece and one end of the back piece. The back piece and the abdomen piece are opened and closed around the hinge 103, and are biased by a connecting member (not shown) in a direction in which the space between the back piece and the abdomen piece is closed.

(Operation of the embodiment)
Next, the operation in the embodiment will be described. FIG. 3 is a flowchart illustrating an operation when displaying the end of normal measurement on the display unit in the embodiment. 4A and 4B are diagrams for explaining display on the display unit in the embodiment, in which FIG. 4A is a display of the display unit 6 during measurement, and FIG. 4B is a display of the display unit 6 during normal operation information display. It is a display.

The biological information measuring device M executes an arithmetic processing program by, for example, activation thereof. Each part 41-44 of the control part 4 is functionally comprised by execution of this arithmetic processing program. Then, the biological information measuring device M measures biological information such as arterial blood oxygen saturation SpO ₂ based on the photoelectric pulse wave signal measured by the measuring unit 2 by the following operation, and the biological information in the measuring unit 2 is measured. In the case of normal operation from the measurement of the tissue to the fixed display on the display unit 6, normal operation information indicating that the operation is normal is further displayed on the display unit 6.

  Prior to the measurement, the measurement unit 2 is attached to a biological tissue as a measurement site, and the biological information measurement device M starts measurement by operating the operation unit 9.

  The flowchart shown in FIG. 3 (steps S1 to S5) is roughly composed of a measurement flow of steps S1 to S3 and a normal operation information display flow of steps S4 to S5.

<Measurement Flow (Step S1 to Step S3)>
In step S <b> 1, when an instruction to start measurement is given from the operation unit 9 to the control unit 4, the measurement control unit 41 controls the light emitting unit 21, the light receiving unit 22, the I / V conversion unit 31, and the A / D conversion unit 32. Then, measurement of biological information such as SpO ₂ value is performed. The measurement control unit 41 causes the light emitting unit 21 to emit light and causes the light receiving unit 22 to acquire a photoelectric conversion signal that is a biological information signal in synchronization with the light emission timing. Further, the photoelectric conversion signal acquired by the light receiving unit 22 is a current signal, is converted into a voltage signal by the I / V conversion unit 31, and is output to the A / D conversion unit 32 as a photoelectric pulse wave signal. The measurement control unit 41 causes the A / D conversion unit 32 to convert the photoelectric pulse wave signal from analog to digital.

The analysis processing unit 42 performs a predetermined analysis based on the digital photoelectric pulse wave signal output from the A / D conversion unit 32, and the light amount and pulse wave amplitude of each light received by the light receiving unit 22 and infrared light. Amplitude ratio with red light, instantaneous SpO ₂ value, 1 second SpO ₂ value and display SpO ₂ , pulse rate, perfusion index, etc. are calculated. The display control unit 44 causes the display unit 6 to sequentially display the display SpO ₂ value calculated by the analysis processing unit 42. Further, the analysis processing unit 42 sequentially stores the calculated various data in the storage unit 5 together with the timing information. Note that the data stored in the storage unit 5 only needs to be used for stability determination and determination of the degree of stability.

In step S1 to step S2, the display unit 6 displays a display SpO ₂ value 6a and a display pulse value 6b, for example, as shown in FIG.

In step S2, the determination unit 43 determines whether or not the measurement unit 2 is worn on the finger by the method described above. When the determination unit 43 determines that the measurement unit 2 is attached to the finger (Yes in step S2), the process returns to step S1, the measurement control unit 41 continues the measurement, and a new display SpO ₂ value is displayed. Each time it is calculated, the display unit 6 updates and displays the currently displayed display SpO ₂ value.

  On the other hand, when the determination unit 43 determines in step S2 that the measurement unit 2 has been removed from the finger (No in step S2), the process proceeds to step S3.

In step S3, the display control unit 44 fixedly displays the display SpO ₂ value on the display unit 6, and the measurement control unit 41 causes the measurement unit 2 to stop measurement. Here, the fixed display indicates that the same display SpO ₂ value is continuously displayed as it is after the measurement is completed. More specifically, when the determination unit 43 determines that the measurement has been completed, the latest display SpO ₂ value and the latest display pulse value currently displayed on the display unit 6 are continuously displayed. The display control unit 44 controls the display unit 6 so as to continue (fixed display).

<Normal operation information display flow (steps S4 to S5)>
In step S4, the display control unit 44 causes the display unit 6 to display a normal measurement completion mark 6c that is normal operation information in the determination unit 43. Instead of displaying normal operation information, the display control unit 44 may cause the notification unit 7 to output an alarm sound for notifying the operator.

For example, as shown in FIG. 4B, the display unit 6 displays the normal measurement completion mark 6c while displaying the display SpO ₂ value 6a and the display pulse value 6b fixedly displayed in step S3. The normal measurement completion mark 6c is a display indicating that the displayed SpO ₂ value is normally measured, and is further displayed after the fixed display. The normal measurement completion mark 6c may be displayed in this way (in other examples, “HOLD”, “OK”, etc.), or may be displayed with a pictorial symbol or the like.

In step S5, after the display unit 6 displays a fixed display of the display SpO ₂ value and a normal measurement completion mark for a predetermined time (for example, 1 minute), the measurement control unit 41 supplies power to the biological information measuring apparatus M. Is turned off.

  Thus, when the biological information measuring apparatus M operates normally, a normal measurement completion mark is displayed on the display unit 6. Therefore, since the normal operation information is not displayed on the display unit 6, the measurement subject does not visually observe the display unit during the measurement, and some abnormality has occurred in the biological information measuring apparatus M from the measurement to the fixed display. Can be confirmed. Such an abnormality is not limited to the display unit being fixed due to a failure. For example, if any abnormality such as an electric circuit, a control program, or a special measurement condition occurs between the measurement of the biological information measuring device M and the fixed display operation, the display control unit 44 performs normal operation information after the fixed display of the display unit 6. Can not be displayed, the measurement subject can confirm that an abnormality has occurred in the biological information measuring apparatus M.

(Other embodiments)
In another embodiment, the measurement unit 2 may further include a detection unit (not shown). The detection unit outputs a signal including the information to the control unit 4 when the measurement unit 2 is attached to the biological tissue, and outputs a signal including the information to the control unit 4 when the measurement unit 2 is removed from the biological tissue. The determination unit 43 detects a signal output from the detection unit instead of the amount of light received by the light receiving unit 22, and detects whether or not a living tissue is attached to the measurement unit 2 during measurement based on the signal ( judge. The detection unit is, for example, an electrostatic sensor that uses an increase in capacitance when a living tissue approaches, a temperature sensor that uses radiation from the living tissue, a switch that detects opening and closing of a hinge, and the like. Instead of the operation unit 9, the detection unit may be used as a switch for turning on / off the power, a switch for instructing measurement start, and other various operations.

In still another embodiment, the display unit 6 may further display the degree of stability and the perfusion index. As described above, the degree of stability is calculated by the analysis processing unit 42 and displayed on the display unit 6 by the display control unit 44. By displaying the degree of stability on the display unit 6, the reliability of the displayed SpO ₂ value can also be recognized. Therefore, the operator can recognize the correct SpO ₂ value and its reliability without continuing to visually check the display value from the start of measurement. Whether or not the apparatus has been correctly operated can also be confirmed by the display 6c. Moreover, when the perfusion index is displayed, the accuracy of the measurement value is improved when the measurement unit 2 is attached to the living tissue.

  In order to express the present invention, the present invention has been properly and fully described through the embodiments with reference to the drawings. However, those skilled in the art can easily change and / or improve the above-described embodiments. It should be recognized that this is possible. Therefore, unless the modifications or improvements implemented by those skilled in the art are at a level that departs from the scope of the claims recited in the claims, the modifications or improvements are not covered by the claims. To be construed as inclusive.

M biological information measuring device 1 device main body 2 measuring unit 4 control unit 5 storage unit 6 display units 6a to 6c display 7 notification unit 8 power supply unit 9 operation unit 21 light emitting unit 22 light receiving unit 31 I / V conversion unit 32 A / D conversion Unit 41 measurement control unit 42 calculation unit 43 determination unit 44 display control unit 101 first exterior member 102 second exterior member 103 hinge

Claims (5)

A plurality of light having different wavelengths from each other to emit light to the living tissue, and a measuring unit that receives each light transmitted or reflected by the living tissue;
Based on each light transmitted or reflected through the biological tissue, an analysis processing unit that calculates biological information of the biological tissue;
A display unit for displaying the biological information calculated by the analysis processing unit;
A determination unit that determines whether measurement of the living tissue by the measurement unit is completed,
When the determination unit determines that the measurement of the biological tissue by the measurement unit is completed, the display unit displays the biological information as a fixed display, and from the measurement of the biological tissue in the measurement unit, the display unit A biological information measuring device further displaying normal operation information indicating that the device has been normally operated when the device is normally operated until a fixed display is achieved. The measurement unit is detachably attached to the living tissue,
The determination unit detects whether or not the measurement unit is attached to the biological tissue during measurement, and detects that the measurement unit is detached from the biological tissue. The biological information measuring device according to claim 1, wherein it is determined that the measurement has been completed. The calculation unit further determines the stability of the biological information,
The biological information measuring apparatus according to claim 1, wherein the display unit further displays the stability.   The biological information measuring device according to any one of claims 1 to 3, further comprising a notification unit that notifies the normal operation information by sound.   The biological information measuring apparatus according to any one of claims 1 to 4, wherein the biological information is oxygen saturation of arterial blood.

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