JP2018161512A - Measurement system and patient state evaluation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correctly determine a state of a circulatory system of a subject.SOLUTION: A first sensor 10 emits light to a first region of a subject, pressurizes the first region, and measures reflection light or transmitted light from the first region. A second sensor 11 emits light to a second region of a subject, pressurizes the second region, and measures reflection light or transmitted light from the second region. A first measurement value calculation section 212 calculates an index related to a blood oxygen saturation or a blood re-injection time on the basis of a change of an amount of light reception to be measured by the first sensor 10 (calculates a first measurement value). A second measurement value calculation section 213 calculates a blood oxygen saturation or a blood re-injection time on the basis of a change of light reception to be measured by the second sensor 11 (calculates a second measurement value). An evaluation section 214 evaluates a circulatory system of a subject on the basis of comparison processing using the first measurement value and the second measurement value.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a measurement system and a patient condition evaluation method.

  One of the indices for grasping the tissue perfusion of a subject is blood refilling time. The blood refill time is treated as a simple index for evaluating the presence or absence of shock. The blood refilling time is widely used in the field of emergency medicine, such as determination of necessity of infusion and triage (priority evaluation at the time of occurrence of many injuries and diseases). The degree of blood oxygenation (arterial blood oxygen saturation) is also important for determining whether the blood supply to the living tissue is sufficiently performed.

  In general measurement of blood refilling time, a medical worker presses a living tissue such as a fingernail of a subject, and visually confirms a change in the color of the nail or skin after releasing the pressure. If it returns to the original color within approximately 2 seconds, it is judged as normal. However, since it is a technique in which a living tissue is compressed by hand and a change in skin color is visually confirmed, it is subject to quantitativeness and errors are likely to occur.

  Therefore, it has been proposed to measure the blood refill time using a mechanism similar to a pulse oximeter (Patent Document 1). In this method, light having a wavelength absorbed by blood is incident on a living tissue (mainly a fingertip), and the intensity of the light transmitted through the living tissue is measured by an optical sensor. At this time, if the living tissue is compressed using the actuator, blood is excluded from the living tissue at the location, and thus the intensity of transmitted light increases. When the compression is released, blood is filled in the living tissue at the location, so that the intensity of transmitted light decreases. The blood refill time is specified based on the time from when the pressure is released until the transmitted light intensity returns to the original level.

JP 2012-115640 A JP 2014-147474 A JP 2014-147473 A

  It is known that blood flow near the fingertip is greatly affected by temperature and nervous system activity. On the other hand, the blood flow near the forehead is less affected by temperature and nervous system activity. It is known that percutaneous arterial blood oxygen saturation (SpO2) using a pulse oximeter cannot be measured with a fingertip due to poor peripheral circulation, but is likely to be measured with a forehead.

  Even in the measurement of blood refilling time, the waveform measured near the fingertip is affected by both peripheral circulation and central circulation. Therefore, even if the measurement is performed by detecting transmitted light as described above, the measured value of the blood refill time near the fingertip may be different from the measured value of the blood refill time near the forehead.

  In the case of a subject with arteriosclerosis obliterans (ASO), the measured blood refill time measured with one fingertip is different from the measured blood refill time measured with the other fingertip. There is. That is, the measured value of the blood refilling time of the hand on the side where the occlusion of the blood vessel is progressing increases.

  Thus, the measured value of the blood refill time is affected by various factors. Therefore, in the measurement of the blood refilling time for one place on the subject's body, there is a problem that the state of the subject's circulatory system cannot be judged correctly.

  The same can be said for the measurement of an index related to blood oxygen saturation. That is, the measured value of the index related to blood oxygen saturation may vary depending on the measurement location. For this reason, there is a possibility that the state of the subject's circulatory system cannot be correctly determined in the measurement for one place on the subject's body.

  That is, there is a problem in that the state of the subject's circulatory system cannot be correctly determined in the measurement of an index related to the blood refill time or blood oxygen saturation only for a certain part of the subject's body.

  This invention is made | formed in view of the said subject, and makes it a main objective to provide the measuring system, measuring apparatus, and patient state evaluation method which can judge the state of a test subject's circulatory system correctly.

One aspect of the measurement system according to the present invention is:
A first sensor that emits light to the first part of the subject, presses the first part, and measures reflected light or transmitted light from the first part;
A second sensor that emits light to the second part of the subject, presses the second part, and measures reflected light or transmitted light from the second part;
A first measurement value calculation unit for calculating a first measurement value indicating an index related to blood oxygen saturation based on a change in the amount of received light measured by the first sensor;
A second measurement value calculation unit that calculates a second measurement value indicating an index related to blood oxygen saturation based on a change in the amount of received light measured by the second sensor;
Based on the comparison process using both the first measurement value and the second measurement value, an evaluation unit that evaluates the central circulation and peripheral circulation of the subject or the left-right difference of the peripheral circulation,
Is provided.

  The evaluation unit performs evaluation using both the first measurement value relating to the first part and the second measurement value relating to the second part. Thereby, the patient state in which the difference between parts is reflected can be evaluated.

  In the present invention, it is possible to provide a measurement system, a measurement device, and a patient condition evaluation method that can accurately determine the state of the subject's circulatory system.

1 is a block diagram showing a configuration of a measurement system 1 according to a first embodiment. 3 is a flowchart showing a flow of a blood refill time calculation method according to the first exemplary embodiment; 3 is a conceptual diagram illustrating an example of an output screen generated by an output unit 23 according to the first embodiment; FIG. It is a block diagram which shows the structure of the measurement system 1 concerning Embodiment 2. FIG. It is a figure which shows the evaluation method of the evaluation part 214 concerning Embodiment 2. FIG. It is a figure which shows the evaluation method of the evaluation part 214 concerning Embodiment 2. FIG. It is a figure which shows the evaluation method of the evaluation part 214 concerning Embodiment 2. FIG. It is a figure which shows the evaluation method of the evaluation part 214 concerning Embodiment 2. FIG. It is a figure which shows the evaluation method of the evaluation part 214 concerning Embodiment 2. FIG. It is a figure which shows the evaluation method of the evaluation part 214 concerning Embodiment 2. FIG. 10 is a conceptual diagram illustrating an example of an output screen generated by an output unit 23 according to a second embodiment; FIG. 1 is a block diagram showing a configuration of a measurement system 1 according to a first embodiment.

<Embodiment 1>
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a measurement system 1 according to the present embodiment. The measurement system 1 includes a first sensor 10, a second sensor 11, and a measurement device 20.

  The first sensor 10 is used to measure an index related to a subject's blood refill time or blood oxygen saturation. In any measurement, the first sensor 10 compresses the living tissue according to the control from the measuring device 20, emits light to the living tissue, and reflects or transmits light from the living tissue (hereinafter referred to as “reflection”). "Light / transmitted light")). The first sensor 10 emits light of a plurality of wavelengths (first light having a first wavelength λ1 and second light having a second wavelength λ2) when measuring an index related to blood oxygen saturation. Emits light toward. The 1st sensor 10 has elements, such as a photodiode, in an inside, and performs the above-mentioned light emission processing. The 1st sensor 10 has a bag body, for example, and compresses a test subject's living tissue by flowing air into a bag body.

  Similar to the first sensor 10, the second sensor 11 is used to measure an index related to the blood refill time or blood oxygen saturation of the subject. The configuration of the second sensor 11 may be the same as that of the first sensor 10. The first sensor 10 and the second sensor 11 are attached to different locations (for example, left finger and right finger) of the subject. Hereinafter, the part where the first sensor 10 is attached is referred to as a first part, and the part where the second sensor 11 is attached is referred to as a second part.

  In addition, the 1st sensor 10 and the 2nd sensor 11 should just be a suitable shape according to an attachment location. For example, when attaching to a fingertip, the 1st sensor 10 or the 2nd sensor 11 should just be a probe type shape similarly to general SpO2 measurement. Moreover, when attaching to a forehead etc., the 1st sensor 10 or the 2nd sensor 11 should just be a sensor of the type adhere | attached on a test subject with a seal-like adhesive member.

  The first sensor 10 and the second sensor 11 measure the reflected light / transmitted light from the living tissue, and notify the measuring device 20 of the measured amount of received light.

  The measuring device 20 includes a control unit 21, an input unit 22, and an output unit 23. The control unit 21 controls the measurement device 20 and various sensors (the first sensor 10 and the second sensor 11), and includes a pressure control unit 211, a first measurement value calculation unit 212, and a second measurement value calculation unit. 213.

  The pressure control unit 211 controls the compression strength of the first sensor 10 and the second sensor 11 on the living tissue of the subject. Specifically, the pressure control unit 211 controls the compression strength applied to the subject by the first sensor 10 and the second sensor 11 by controlling the amount of air flowing into the air bag.

  Here, the pressure control unit 211 performs control so that the pressure release start timing of the first sensor 10 and the pressure release start timing of the second sensor 11 are substantially simultaneous. By starting the compression release of the first part and the second part substantially simultaneously, blood refilling in both parts is started at the same timing.

  The pressure control unit 211 controls the time from the start of compression release by the first sensor 10 to the end of compression and the time from the start of compression release by the second sensor 11 to the end of compression. It is preferable. Thereby, the compression conditions for the first part and the second part are substantially the same, and more accurate measurement values (first measurement value and second measurement value described later) can be obtained.

  The first measurement value calculation unit 212 calculates an index related to the blood refill time or the blood oxygen saturation based on the amount of received light measured by the first sensor 10. An example of a method for calculating a blood refill time and a method for measuring an index related to blood oxygen saturation is described in detail in Patent Documents 2 and 3, which are applications of the inventor of the present invention. Therefore, the details of the calculation method of the index related to the blood refill time and the blood oxygen saturation will be omitted, and the outline of the calculation method will be briefly described.

  First, an outline of a blood refill time calculation method will be described with reference to FIG. The control unit 21 starts light emission and light reception of the first sensor 10 at a predetermined timing (for example, every 30 minutes) (S11). At this time, the pressure control unit 211 performs control so as not to compress the living tissue. The first measurement value calculation unit 212 measures the amount of received light before pressing the living tissue from the first sensor 10 (S12). The pressure control unit 211 starts compression on the living tissue after acquiring the received light amount before compression (S13). The first measurement value calculation unit 212 measures the amount of received light in the compressed state of the living tissue from the first sensor 10 (S14). The pressure control unit 211 releases the pressure on the living tissue after performing sufficient pressure (S15). The first measurement value calculation unit 212 calculates or calculates the time required for the amount of received light to decay to a value close to the level before the compression from the timing when the pressure on the living tissue is released as the blood refill time ( S16).

  The above is the outline of the blood refill time calculation method. Next, an outline of a method for calculating an index related to blood oxygen saturation will be described.

  The first measurement value calculation unit 212 corresponds to the first signal S1 corresponding to the received light intensity of the first light (first wavelength λ1) from the first sensor 10 and the received light intensity of the second light (second wavelength λ2). The second signal S2 is acquired. The first measurement value calculation unit 212 acquires the light attenuation A1 of the first light based on the first signal S1, and acquires the light attenuation A2 of the second light based on the second signal S2. Then, the first measurement value calculation unit 212 acquires the blood-derived dimming degree Ab based on the dimming degrees A1 and A2. Then, the first measurement value calculation unit 212 acquires information ΔAb related to blood oxygen saturation based on the amount of change in the light attenuation Ab, or blood oxygen saturation S when light having three or more wavelengths is used. In this specification, “an index related to blood oxygen saturation” is a concept including the above-described ΔAb or blood oxygen saturation S. Furthermore, the “index related to blood oxygen saturation” is calculated from the amount of received light obtained by pressing a living body and emitting a plurality of wavelengths in addition to ΔAb and blood oxygen saturation S. Others may be used as long as they relate to saturation.

  The above is the outline of the calculation method of the index related to the blood oxygen saturation. The first measurement value calculation unit 212 may measure either the blood refilling time or the index related to the blood oxygen saturation according to the operation from the input unit 22 (operation of a medical worker).

  The second measurement value calculation unit 213 measures an index related to the blood refilling time or blood oxygen saturation of the second part based on the amount of light received by the second sensor 11 attached to the second part. The measurement method is the same as that of the first measurement value calculation unit 212.

  Hereinafter, an index related to the blood refill time or blood oxygen saturation measured by the first measurement value calculation unit 212 is also referred to as “first measurement value”, and the blood refill time measured by the second measurement value calculation unit 213. Alternatively, an index related to blood oxygen saturation is also referred to as “second measured value”.

  The first measurement value calculation unit 212 and the second measurement value calculation unit 213 may be configured to measure only one of the indices related to the blood refill time or the blood oxygen saturation.

  The first measurement value calculation unit 212 and the second measurement value calculation unit 213 supply the first measurement value and the second measurement value to the output unit 23.

  The output unit 23 outputs the first measurement value and the second measurement value. Here, the output means, for example, that the first measurement value and the second measurement value are displayed on a display screen of a display provided on the housing of the measuring device 20, and the first measurement value and the second measurement value are displayed on the printing paper. Processing such as printing and outputting, transmitting the first measurement value and the second measurement value to another device having a display device (display) is included.

  FIG. 3 is a conceptual diagram illustrating an example of an output screen generated by the output unit 23. In the example of FIG. 3, a shape in which the first sensor 10 and the second sensor 11 are attached to the fingertips and a display display is provided on the housing is illustrated. The display screen 30 displays that the first measurement value (blood refill time (1)) is 3.9 seconds and the second measurement value (blood refill time (2)) is 2.2 seconds. Has been. The medical staff can recognize that the peripheral circulation on the first sensor 10 side is bad by referring to the display screen 30.

  The input unit 22 is an input interface that receives an input from a medical worker. The input unit 22 is, for example, a button, a knob, a touch panel, or the like provided on the measuring device 20. A medical worker inputs an operation such as measurement start via the input unit 22.

  Then, the effect of the measurement system 1 concerning this Embodiment is demonstrated. As described above, the pressure control unit 211 starts releasing the compression of the first sensor 10 and the second sensor 11 at substantially the same timing. Thereby, the start timing of blood refilling in the first part and the second part is substantially the same. By this timing being the same, the difference in the blood circulation state between the plurality of parts is accurately reflected in the first measurement value and the second measurement value. The medical staff can correctly determine the state of the subject's circulatory system by referring to the first measurement value and the second measurement value.

  For example, when (the first part = right finger, the second part = left finger) and the difference in blood refill time is large, the medical worker may have obstructive arteriosclerosis (ASO) in the hand with the larger measured value. Recognize that there is a fear. Similarly, when (first part = right finger, second part = left finger) and there is a large difference in the index related to blood oxygen saturation after a certain time from the release of compression, the medical staff has a small measured value. It can be recognized that there is a risk of obstructive arteriosclerosis (ASO) in one hand.

  When (first part = forehead, second part = left finger (or right finger)), the medical staff can also recognize the state of central circulation and peripheral circulation of the subject.

  Even if the start timing of the pressure release between the first sensor 10 and the second sensor 11 is slightly shifted (for example, about 0.1 second), the time difference between the two timings is within a predetermined time (for example, within 0.3 second). In other words, blood refilling at both sites (first site and second site) is started almost simultaneously. Therefore, the pressure control unit 211 may control so that the time difference between the timing at which the first sensor 10 starts to release the pressure and the timing at which the second sensor 11 starts to release the pressure is within a predetermined time (preferably abbreviated). Good at the same time). Although the accuracy is lowered, it is possible to measure a substantially desired value even if the second sensor is released without much time after the measurement using the first sensor 10 is finished. Therefore, the above-mentioned predetermined time is a concept having a value range of about 0 to 10 seconds although it is about 0 to 0.3 seconds (preferably 0 seconds).

<Embodiment 2>
Next, the measurement system 1 according to the second embodiment of the present invention will be described. The measurement system 1 according to the present embodiment is characterized in that the subject's circulatory system is evaluated in the measurement device 20 using the first measurement value and the second measurement value. The difference between the measurement system 1 according to the present embodiment and the first embodiment will be described below. In the following description, a processing unit having the same name and reference numeral as in the first embodiment performs the same operation as in the first embodiment unless otherwise specified.

  FIG. 4 is a block diagram showing a configuration of the measurement system 1 according to the present embodiment. The measurement apparatus 20 in the measurement system 1 includes an evaluation unit 214 in the control unit 21 in addition to the configuration of the first embodiment (FIG. 1).

  The evaluation unit 214 includes a first measurement value (an index related to blood refill time or blood oxygen saturation) from the first measurement value calculation unit 212, and a second measurement value (blood reconstitution) from the second measurement value calculation unit 213. An indicator related to filling time or blood oxygen saturation).

  The evaluation unit 214 evaluates the subject's circulatory system using the first measurement value and the second measurement value. The indices relating to the blood refilling time and the blood oxygen saturation are both indices indicating whether the blood circulation to the living body part is good. Therefore, it is possible to use the blood refill time as the first measurement value and the second measurement value, or to use an index related to the blood oxygen saturation. In the following description, it is assumed that the blood refill time is used as the first measurement value and the second measurement value. Details of the evaluation of the evaluation unit 214 will be described below.

(Evaluation method 1)
The evaluation method 1 performs evaluation using a comparison between the first measurement value and the threshold value and a comparison between the second measurement value and the threshold value. FIG. 5 shows an evaluation method of the evaluation unit 214 when (first part = fingertip, second part = forehead).

  The threshold value Tth1 is determined based on a general reference value (for example, 3 seconds) of blood refilling time. Note that the medical staff may be able to set the threshold value Tth1 in consideration of the age, gender, past illness, etc. of the subject. When the first measurement value (the blood refill time of the fingertip) is larger than the threshold value Tth1, it indicates that the blood circulation (peripheral circulation) to the fingertip is not good. Further, when the second measurement value (the blood refilling time of the forehead) is larger than the threshold value Tth1, it indicates that the blood circulation to the forehead is not good. Therefore, the evaluation unit 214 evaluates the subject's circulatory system as described below (FIG. 5).

Case 1: good central and peripheral circulation Case 2: good central circulation but poor peripheral circulation Case 3: good central circulation but reduced blood flow to the head Case 4: poor central and peripheral circulation (or Central circulation is extremely bad)

  The evaluation unit 214 notifies the medical staff of the evaluation result from the output unit 23. Therefore, the medical staff can perform an appropriate treatment according to this notification. For example, when only the peripheral blood flow is bad (Case 2), the skin temperature of the fingertip is low, or the influence of vasoconstrictor administration is considered. Therefore, the medical staff may perform a treatment that improves the peripheral circulation.

  FIG. 6 is a table showing the evaluation method of the evaluation unit 214 when (first part = left fingertip, second part = right fingertip).

  When the first measurement value (the blood refill time of the left fingertip) is larger than the threshold value Tth1, it indicates that the blood circulation (peripheral circulation) to the left fingertip is not good. Further, when the second measurement value (the blood refilling time of the right hand fingertip) is larger than the threshold value Tth1, it indicates that the blood circulation (peripheral circulation) to the right fingertip is not good. Therefore, the evaluation unit 214 evaluates the subject's circulatory system as described below (FIG. 6).

Case 5: Peripheral circulation is good regardless of left and right Case 6: Peripheral circulation related to left hand is poor (suspicion of ASO)
Case 7: Peripheral circulation related to right hand is poor (suspicion of ASO)
Case 8: Poor peripheral circulation (or central circulation) regardless of left or right

  As described above, the evaluation unit 214 determines that the first measurement value and the second measurement value are both smaller than the threshold value, and determines that there is some abnormality in other cases. The evaluation unit 214 notifies the medical staff of the evaluation result from the output unit 23. Therefore, the medical staff can perform an appropriate treatment according to this notification. For example, if only the peripheral circulation of one fingertip is bad, the medical staff may treat and deal with it as suspected as obstructive arteriosclerosis (ASO).

  The above is the outline of the evaluation method 1. In the above description, it is assumed that the first measurement value and the second measurement value are the blood refilling time. However, the evaluation unit 214 can evaluate the index related to the blood oxygen saturation in the same manner. When ΔAb is used as an index related to blood oxygen saturation, the threshold value Tth1 may be determined based on, for example, 0.1. When the blood oxygen saturation S is used, the threshold value Tth1 may be set to about 10%, for example.

(Evaluation method 2)
Next, the second evaluation method will be described. The evaluation method 2 performs evaluation based on a comparison between a difference between the first measurement value and the second measurement value and a predetermined threshold value. FIG. 7 shows an evaluation method of the evaluation unit 214 when (first part = fingertip, second part = forehead).

  When the value (difference value) obtained by subtracting the second measurement value (blood refilling time of the forehead) from the first measurement value (blood refilling time of the fingertip) is larger than the threshold Tth2, the blood flow (peripheral circulation) of the fingertip is It is worse than blood flow to the forehead (central circulation). On the other hand, when the value (difference value) obtained by subtracting the first measurement value (blood refill time of the fingertip) from the second measurement value (blood refill time of the forehead) is larger than the threshold value Tth2, no problem can be detected in the peripheral circulation. Indicates that the blood flow of the forehead is bad. Therefore, the evaluation unit 214 evaluates the subject's circulatory system as described below (FIG. 7).

Case 9: Poor peripheral circulation Case 10: Poor blood circulation to forehead Case 11: No difference between fingertip and forehead for blood circulation

  The medical staff may perform an appropriate treatment according to the evaluation of the evaluation unit 214. Subsequently, an evaluation method of the evaluation unit 214 in the case of (first part = left fingertip, second part = left fingertip) is shown below (FIG. 8).

Case 12: Poor peripheral circulation related to left hand (suspicion of ASO)
Case 13: Peripheral circulation related to right hand is poor (suspicion of ASO)
Case 14: There is no difference between left and right regarding blood circulation

  When the difference in blood refilling time is large as shown in FIG. 8, the evaluation unit 214 evaluates that there is a suspicion such as obstructive arteriosclerosis (ASO). The medical staff may perform an appropriate treatment according to the evaluation of the evaluation unit 214.

  In FIGS. 7 and 8, the threshold value Tth2 is used in both the comparison with (first measurement value−second measurement value) and the comparison with (second measurement value−first measurement value). I can't. That is, a comparison process using two threshold values, that is, a threshold value to be compared with (first measurement value−second measurement value) and a threshold value to be compared with (second measurement value−first measurement value) may be performed.

(Evaluation method 3)
Next, the third evaluation method will be described. Evaluation method 3 includes evaluation method 1 (evaluation method using the difference between the first measurement value and the threshold and the difference between the second measurement value and the threshold) and the evaluation method 2 (difference between the first measurement value and the second measurement value). Both methods of the evaluation method) are used.

  The following (FIG. 9) shows the evaluation method of the evaluation unit 214 when (first part = fingertip, second part = forehead).

Case 15: generally normal, but slightly fingertip (peripheral circulation) Case 16: generally normal but slightly poor blood flow to the forehead Case 17: good central and peripheral circulation Case 18: no case Case 19: blood flow to the forehead Bad Case 20: Both fingertip (peripheral circulation) and central circulation (forehead) are slightly bad (both values are close to threshold Tth1)
Case 21: Blood flow to the fingertip (peripheral circulation) is poor (ASO risk)
Case 22: Case that does not occur Case 23: Both fingertip (peripheral circulation) and central circulation (forehead) are slightly poor (both values are close to the threshold value Tth1)
Case 24: Both central circulation and peripheral circulation are poor, especially blood flow to the fingertip (peripheral circulation) is bad Case 25: Both central circulation and peripheral circulation are bad, especially blood flow to the forehead is bad Case 26: Central circulation is very poor Bad

  As described above, the evaluation unit 214 evaluates the subject's circulatory system based on the difference between the blood refill time and the normal value at each site and the blood refill time between the sites. By performing evaluation based on such a plurality of subtraction processes, the evaluation unit 214 can perform more accurate evaluation. In the evaluation using Table 1, Table 3, and Table 5, the second measurement value is acquired from the vicinity of the forehead. However, the second measurement value may be acquired from the nose or the earlobe. That is, the second measurement value may be obtained from the vicinity of the subject's head.

  Subsequently, an evaluation method of the evaluation unit 214 in the case of (first part = left fingertip, second part = right fingertip) is shown below (FIG. 10).

Case 27: almost normal but left fingertip (peripheral circulation in the left hand) is slightly worse Case28: almost normal but right fingertip (peripheral circulation in the right hand) is slightly worse Case29: no difference between left and right, good central circulation and peripheral circulation Case30 : Case that does not occur Case 31: Poor peripheral circulation of the right hand (ASO fear)
Case 32: One or both of peripheral circulation and central circulation are slightly bad (both values are close to threshold value Tth1)
Case 33: poor peripheral circulation of the left hand (ASO fear)
Case 34: Case that does not occur Case 35: One or both of peripheral circulation and central circulation are slightly bad (both values are close to threshold value Tth1)
Case 36: One or both of peripheral circulation and central circulation are bad, especially the peripheral circulation of the left hand is bad Case 37: One or both of peripheral circulation and central circulation is bad, especially the peripheral circulation of the right hand is bad Case 38: Peripheral circulation and central circulation One or both is bad

  The evaluation unit 214 evaluates the subject's circulatory system as described above. When both the first measurement value and the second measurement value are large values (Case 38), the evaluation unit 214 cannot determine whether the peripheral circulation of both hands is bad or the central circulation is bad. In such a case, evaluation may be performed in consideration of blood refilling time measured by attaching a third sensor (not shown) to the forehead or the like to the subject.

  In the above description, the first measurement value and the second measurement value are compared with the threshold value Tth1, but a threshold value may be provided for each measurement value. Further, the threshold value to be compared with (first measurement value-second measurement value) and the threshold value to be compared with (second measurement value-first measurement value) may be different (in place of threshold value Tth2, two threshold values are set). May be provided.)

  The above is an example of the evaluation method by the evaluation unit 214, but the evaluation unit 214 evaluates the subject's circulatory system by other methods as long as the evaluation unit 214 performs evaluation using the first measurement value and the second measurement value. May be. The evaluation performed by the evaluation unit 214 includes not only normal / abnormal determination as described above but also a simple subtraction process of calculating the difference between the first measurement value and the threshold and the difference between the second measurement value and the threshold. Shall be. The difference values calculated by the evaluation unit 214 (the difference between the first measurement value and the threshold value, and the difference between the second measurement value and the threshold value) are output (displayed, printed, file written, etc.) via the output unit 23. It may be a configuration. Similarly, the evaluation performed by the evaluation unit 214 includes a simple subtraction process of calculating a difference between the first measurement value and the second measurement value. The difference value (difference value between the first measurement value and the second measurement value) calculated by the evaluation unit 214 may be output (display, print, file write, etc.) via the output unit 23.

  Next, a display example by the output unit 23 will be described. FIG. 11 is a conceptual diagram showing a display screen on which the evaluation result of the evaluation unit 214 is displayed. The display screen 30 displays that the first measurement value (blood refill time (1)) is 3.9 seconds and the second measurement value (blood refill time (2)) is 2.2 seconds. Has been. Further, the evaluation result of the evaluation unit 214 is displayed on the display screen 30. In the example of FIG. 5, it is displayed that there is a suspicion of obstructive arteriosclerosis (ASO). The medical staff can recognize the evaluation result of the subject's circulatory system by referring to the display screen 30.

  Note that the output unit 23 may be configured to output not only the display screen 30 but also an alarm sound according to the evaluation result of the evaluation unit 214. That is, the output unit 23 may be configured to output an alarm sound when the evaluation unit 214 determines that the subject's circulatory system is abnormal.

  Then, the effect of the measurement system 1 concerning this Embodiment is demonstrated. The measurement system 1 according to the present embodiment is configured to evaluate a subject's circulatory system using measurement values (first measurement value, second measurement value) related to blood circulation at a plurality of locations. When the measurement system 1 evaluates the circulatory system, even a medical worker with poor diagnosis of the circulatory system can accurately grasp the state of the subject's circulatory system.

  In the evaluation method 1 described above, the evaluation is performed based on a threshold value determined based on the normal value of the blood refill time (or an index related to blood oxygen saturation). Thereby, the medical staff can know the evaluation based on whether the blood circulation of each part is normal.

  The evaluation method 2 described above performs an evaluation based on whether or not the difference between the first measurement value and the second measurement value is equal to or greater than a predetermined threshold value. Thereby, the medical staff can know the evaluation result which detected the deterioration (for example, ASO) etc. of partial blood circulation correctly.

  In addition, the evaluation method 3 described above includes the evaluation method 1 (an evaluation method using the difference between the first measurement value and the threshold and the difference between the second measurement value and the threshold) and the evaluation method 2 (the first measurement value and the second measurement). The evaluation method using the difference between values) is used. That is, the evaluation unit 214 performs evaluation based on whether the first measurement value and the second measurement value are normal values and whether the difference between the first measurement value and the second measurement value is too large. Accordingly, the medical staff can more accurately recognize the blood circulation state and the left-right difference state of each part.

  The output unit 23 outputs (preferably displays) the evaluation result of the evaluation unit 214 in addition to the first measurement value and the second measurement value. As a result, even an inexperienced medical worker can appropriately recognize the state of the subject's circulatory system.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiments. However, the present invention is not limited to the embodiments already described, and various modifications can be made without departing from the scope of the invention. It goes without saying that it is possible.

  As described above, the measurement system 1 can perform evaluation using three or more blood refill times (or an index related to blood oxygen saturation) measured by attaching three or more sensors to the subject. is there.

  Moreover, the measurement system 1 has only one sensor, and it is also possible to measure the first part and the second part in order using the sensor (configuration in FIG. 12). That is, a first measurement value (an index related to blood refill time or blood oxygen saturation) is calculated from the first part (first calculation step), and then the second measurement value (blood refill time or An index related to blood oxygen saturation is calculated (second calculation step). Thereafter, the subject's circulatory system may be evaluated using the first measurement value and the second measurement value using the above-described method (evaluation step). Even in this case, the evaluation using the measurement values related to blood circulation at a plurality of sites is performed, so that the subject's circulatory system can be appropriately evaluated.

DESCRIPTION OF SYMBOLS 1 Measurement system 10 1st sensor 11 2nd sensor 20 Measuring apparatus 21 Control part 211 Pressure control part 212 1st measurement value calculation part 213 2nd measurement value calculation part 214 Evaluation part 22 Input part 23 Output part 30 Display screen

Claims (11)

A first sensor that emits light to the first part of the subject, presses the first part, and measures reflected light or transmitted light from the first part;
A second sensor that emits light to the second part of the subject, presses the second part, and measures reflected light or transmitted light from the second part;
A first measurement value calculation unit for calculating a first measurement value indicating an index related to blood oxygen saturation based on a change in the amount of received light measured by the first sensor;
A second measurement value calculation unit that calculates a second measurement value indicating an index related to blood oxygen saturation based on a change in the amount of received light measured by the second sensor;
Based on the comparison process using both the first measurement value and the second measurement value, an evaluation unit that evaluates the central circulation and peripheral circulation of the subject or the left-right difference of the peripheral circulation,
Measuring system. A first sensor that emits light to the first part of the subject, presses the first part, and measures reflected light or transmitted light from the first part;
A second sensor that emits light to the second part of the subject, presses the second part, and measures reflected light or transmitted light from the second part;
A first measurement value calculation unit for calculating a first measurement value indicating a blood refilling time based on a change in the amount of received light measured by the first sensor;
A second measurement value calculation unit that calculates a second measurement value indicating a blood refilling time based on a change in the amount of received light measured by the second sensor;
Based on the comparison process using both the first measurement value and the second measurement value, an evaluation unit that evaluates the central circulation and peripheral circulation of the subject or the left-right difference of the peripheral circulation,
Measuring system.   The measurement system according to claim 1, wherein the evaluation unit performs evaluation based on a comparison between the first measurement value and a threshold value and a comparison between the second measurement value and a threshold value. When one of the first part and the second part is a right fingertip and the other is a left fingertip,
When the first measurement value is smaller than the threshold value and the second measurement value is larger than the threshold value, the evaluation unit evaluates that the peripheral circulation on the left or right side of the subject is abnormal,
The measurement system according to claim 3. When the first part is a fingertip and the second part is a forehead,
The evaluation unit evaluates that the peripheral circulation of the subject is abnormal when the first measurement value is larger than a threshold value and the second measurement value is smaller than the threshold value.
The measurement system according to claim 3.   The evaluation unit according to claim 1, wherein the evaluation unit calculates a difference value between the first measurement value and the second measurement value, and performs an evaluation by comparing the difference value with a threshold value. Measuring system. When one of the first part and the second part is a right fingertip and the other is a left fingertip,
The measurement system according to claim 6, wherein the evaluation unit evaluates that the peripheral circulation on one of the left and right sides of the subject is abnormal when the difference value is larger than a threshold value. When the first part is a fingertip and the second part is a forehead,
The measurement system according to claim 6, wherein the evaluation unit evaluates that the peripheral circulation of the subject is abnormal when the difference value obtained by subtracting the second measurement value from the first measurement value is larger than a threshold value.   The evaluation unit is configured to compare the first measurement value with a predetermined threshold, compare the second measurement value with a predetermined threshold, and the difference between the first measurement value and the second measurement value. The measurement system according to claim 1 or 2, wherein evaluation of central circulation and peripheral circulation or evaluation of left-right difference of peripheral circulation is performed. A first measurement value that calculates a first measurement value indicating an index related to blood oxygen saturation based on a change in the amount of received light measured by a first sensor that performs light emission, light reception, and compression on the first part of the subject. A calculation unit;
Second measurement for calculating a second measurement value indicating an index related to blood oxygen saturation based on a change in the amount of received light measured by a second sensor that emits light, receives light, and presses the second part of the subject. A value calculator,
A measuring apparatus comprising: an evaluation unit that evaluates the central circulation and peripheral circulation of the subject or the left-right difference of the peripheral circulation based on a comparison process using both the first measurement value and the second measurement value. A first measurement value calculation unit that calculates a first measurement value indicating a blood refill time based on a change in the amount of received light measured by a first sensor that performs light emission, light reception, and compression on a first part of the subject;
A second measurement value calculation unit that calculates a second measurement value indicating a blood refilling time based on a change in the amount of received light measured by a second sensor that performs light emission, light reception, and compression on the second part of the subject; ,
Based on the comparison process using both the first measurement value and the second measurement value, an evaluation unit that evaluates the central circulation and peripheral circulation of the subject or the left-right difference of the peripheral circulation,
A measuring apparatus comprising: