阅读说明：本技术 疼痛评估装置、疼痛评估方法和疼痛评估程序 (Pain evaluation device, pain evaluation method, and pain evaluation program ) 是由 山田圭佑 鲛岛充 伊藤环 于 2020-02-19 设计创作，主要内容包括：本发明提供一种能够针对每一个人评估疼痛程度的疼痛评估装置、疼痛评估方法和疼痛评估程序。控制部(21)包括心电波形获取部(21A)和疼痛判定部(21B),心电波形获取部(21A)用于获取用户的心电波形数据；疼痛判定部(21B)根据用户身体上未施加有物理负荷的状态下由心电波形获取部(21A)获取到的第一心电波形数据与用户身体上施加有负荷的状态下由心电波形获取部(21A)获取到的第二心电波形数据的比较,对在施加有负荷状态下用户感受到的疼痛程度进行判定。(The present invention provides a pain evaluation device, a pain evaluation method, and a pain evaluation program capable of evaluating the degree of pain for each person. The control unit (21) comprises an electrocardiographic waveform acquisition unit (21A) and a pain determination unit (21B), wherein the electrocardiographic waveform acquisition unit (21A) is used for acquiring electrocardiographic waveform data of the user; a pain determination unit (21B) determines the degree of pain felt by the user in the state where a load is applied, based on a comparison between first electrocardiographic waveform data acquired by an electrocardiographic waveform acquisition unit (21A) in the state where no physical load is applied to the user's body and second electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition unit (21A) in the state where a load is applied to the user's body.)

1. A pain evaluation device that is a pain evaluation device for evaluating a degree of pain of a user, the pain evaluation device including an electrocardiographic waveform obtaining portion for obtaining electrocardiographic waveform data of the user and a pain determination portion; the pain determination unit determines the degree of pain felt by the user in a state in which the load is applied, based on a comparison between first electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition unit in a state in which the physical load is not applied to the body of the user and second electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition unit in a state in which the load is applied to the body of the user.

2. The pain assessment device according to claim 1, wherein the pain determination part determines the degree of pain according to a difference or a ratio of a PP interval or an RR interval found from two adjacent electrocardiographic waveforms based on the first electrocardiographic waveform data and a PP interval or an RR interval found from two adjacent electrocardiographic waveforms based on the second electrocardiographic waveform data.

3. The pain evaluation device according to claim 2, wherein the pain determination section determines that the degree of pain at which the absolute value of the difference exceeds a threshold value is larger than the degree of pain at which the absolute value is less than or equal to the threshold value.

4. The pain evaluation device according to claim 2, wherein the pain determination section determines that the degree of pain at which the difference between the ratio and the reference value exceeds the threshold value is larger than the degree of pain at which the difference is smaller than or equal to the threshold value.

5. The pain evaluation device according to claim 2, wherein the pain determination section calculates the difference value for each of the first electrocardiographic waveform data and the second electrocardiographic waveform data obtained at different time points, and determines the degree of pain from a plurality of the difference values.

6. The pain evaluation device according to claim 5, wherein the pain determination section determines that the degree of pain when the average of the absolute values of the plurality of the differences exceeds a threshold value is larger than the degree of pain when the average is less than or equal to the threshold value.

7. The pain evaluation device according to claim 2, wherein the pain determination section calculates the ratio for each of the first electrocardiographic waveform data and the second electrocardiographic waveform data obtained at different time points, and determines the degree of pain from a plurality of the ratios.

8. The pain evaluation device according to claim 7, wherein the pain determination section determines that the degree of pain when the difference between the average value of the plurality of ratios and a reference value exceeds a threshold value is larger than the degree of pain when the average value is smaller than or equal to the threshold value.

9. The pain assessment device according to any one of claims 2 to 8, wherein the pain determination unit calculates, as the ratio or the difference, a ratio or a difference between an average of a plurality of the PP intervals or an average of a plurality of the RR intervals based on the first electrocardiographic waveform data and an average of a plurality of the PP intervals or an average of a plurality of the RR intervals based on the second electrocardiographic waveform data.

10. The pain assessment device according to any one of claims 1 to 9, wherein the load applied to the user's body is generated by a dedicated device.

11. A pain evaluation method which is a pain evaluation method for evaluating a pain feeling of a user, the pain evaluation method comprising an electrocardiographic waveform acquiring step for acquiring electrocardiographic waveform data of the user and a pain judging step; the pain determination step determines a degree of pain felt by the user in a state in which the load is applied, based on a comparison between first electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition step in a state in which the physical load is not applied to the body of the user and second electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition step in a state in which the load is applied to the body of the user.

12. A pain evaluation program that is a pain evaluation program for evaluating a user's pain sensation, the pain evaluation program being for causing a computer to execute an electrocardiographic waveform acquisition step for acquiring electrocardiographic waveform data of the user and a pain determination step; the pain determination step determines a degree of pain felt by the user in a state in which the load is applied, based on a comparison between first electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition step in a state in which the physical load is not applied to the body of the user and second electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition step in a state in which the load is applied to the body of the user.

Technical Field

The present invention relates to a pain evaluation device, a pain evaluation method, and a pain evaluation program.

Background

A portable electrocardiograph which is carried by a user on a daily basis is known (see patent documents 1 and 2). Further, non-patent document 1 discloses a finding that pain can be evaluated by a heart rate variability analysis (specifically, a frequency analysis).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2005-000409

Patent document 2: japanese patent laid-open No. 2005-040187

Non-patent document

Non-patent document 1: "development of System for Objective assessment of body feeling Using biological signals" from Page 51 to Page 55 in 2011 of the research result set (No. 20) of the Lishi science and technology prosperity and financial group and subsidy projects "

Disclosure of Invention

Problems to be solved by the invention

Non-patent document 1 describes that a periodic fluctuation of an RR interval, which is an interval between R waves and an R wave that is a maximum amplitude of an electrocardiographic waveform, has a correlation with pain. However, non-patent document 1 performs an absolute evaluation of pain. The pain perception varies from person to person, and the pain level of each person cannot be known by merely observing the periodic fluctuation of the RR interval.

An object of the present invention is to provide a pain evaluation device, a pain evaluation method, and a pain evaluation program capable of evaluating a degree of pain for each person.

Means for solving the problems

(1) A pain evaluation device which is a pain evaluation device (for example, a control section 21 in the following embodiment) for evaluating pain sensation of a user, the pain evaluation device including an electrocardiographic waveform acquiring section for acquiring electrocardiographic waveform data of the user; the pain determination unit determines a degree of pain felt by the user in a state in which the load is applied, based on a comparison between first electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition unit in a state in which the physical load is not applied to the body of the user and second electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition unit in a state in which the load is applied to the body of the user.

According to (1), since the pain degree is determined based on the comparison between the first electrocardiographic waveform data in the state where no physical load is applied to the body and the second electrocardiographic waveform data in the state where a physical load is applied to the body, the pain feeling different for each user can be digitized, for example, and diagnosis by a doctor, treatment of a pain part, and the like can be facilitated.

(2) A pain evaluation device described in (1), wherein the pain determination section determines the degree of pain from a difference or a ratio of a PP interval or an RR interval found from two adjacent electrocardiographic waveforms based on the first electrocardiographic waveform data and a PP interval or an RR interval found from two adjacent electrocardiographic waveforms based on the second electrocardiographic waveform data.

According to (2), the degree of pain can be determined by a simple process.

(3) A pain evaluation device that is the pain evaluation device described in (2), wherein the pain determination section determines that the degree of pain when the absolute value of the difference exceeds a threshold value is larger than the degree of pain when the absolute value is less than or equal to the threshold value.

According to (3), the degree of pain can be determined by a simple process.

(4) A pain evaluation device that is the pain evaluation device described in (2), wherein the pain determination section determines that the degree of pain at which the difference between the ratio and the reference value exceeds a threshold value is larger than the degree of pain at which the difference is smaller than or equal to the threshold value.

According to (4), the degree of pain can be determined by a simple process.

(5) A pain evaluation device which is the pain evaluation device described in (2), wherein the pain judging section calculates the difference value for each of the first electrocardiographic waveform data and the second electrocardiographic waveform data obtained at different time points, and judges the degree of the pain from a plurality of the difference values.

According to (5), since the degree of pain is determined based on the plurality of difference values, the determination accuracy can be improved.

(6) A pain evaluation device that is the pain evaluation device described in (5), wherein the pain determination section determines that the degree of pain when the average value of the absolute values of the plurality of the difference values exceeds a threshold value is larger than the degree of pain when the average value is less than or equal to the threshold value.

According to (6), since the degree of pain is determined based on the plurality of difference values, the determination accuracy can be improved.

(7) A pain evaluation device which is the pain evaluation device described in (2), wherein the pain judging section calculates the ratio for each of the first electrocardiographic waveform data and the second electrocardiographic waveform data obtained at different time points, and judges the degree of the pain from a plurality of the ratios.

According to (7), since the degree of pain is determined based on a plurality of ratios, the determination accuracy can be improved.

(8) A pain evaluation device that is the pain evaluation device described in (7), wherein the pain judging section judges that a degree of pain at which a difference between an average value of the plurality of the ratios and a reference value exceeds a threshold value is larger than a degree of pain at which the average value is less than or equal to the threshold value.

According to (8), since the degree of pain is determined based on a plurality of ratios, the determination accuracy can be improved.

(9) A pain evaluation device according to any one of (2) to (8), wherein the pain determination unit calculates, as the ratio or the difference, a ratio or a difference between an average value of a plurality of the PP intervals or an average value of a plurality of the RR intervals based on the first electrocardiographic waveform data and an average value of a plurality of the PP intervals or an average value of a plurality of the RR intervals based on the second electrocardiographic waveform data.

According to (9), since the influence of the fluctuation of the PP interval or RR interval can be eliminated, the accuracy of determining the degree of pain can be improved.

(10) A pain evaluation device according to any one of (1) to (9), wherein the load applied to the body of the user is generated by a dedicated device.

According to (10), since the second electrocardiographic waveform data can be acquired in a state where a constant load is applied to the user by a dedicated device, for example, a difference in the method of applying a load to an affected part of an injury can be eliminated, so that the pain level of the affected part can be determined with high accuracy.

(11) A pain evaluation method which is a pain evaluation method for evaluating pain sensation of a user, the pain evaluation method comprising an electrocardiographic waveform acquisition step for acquiring electrocardiographic waveform data of the user and a pain determination step; the pain determination step determines a degree of pain felt by the user in a state in which the load is applied, based on a comparison between first electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition step in a state in which the physical load is not applied to the body of the user and second electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition step in a state in which the load is applied to the body of the user.

(12) A pain evaluation program for evaluating a user's pain sensation, the pain evaluation program for causing a computer to execute an electrocardiographic waveform acquiring step for acquiring electrocardiographic waveform data of the user and a pain judging step; the pain determination step determines a degree of pain felt by the user in a state where the load is applied, based on a comparison between first electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition step in a state where the physical load is not applied to the body of the user and second electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition step in a state where the load is applied to the body of the user.

Effects of the invention

According to the present invention, it is possible to provide a pain evaluation device, a pain evaluation method, and a pain evaluation program capable of evaluating the degree of pain for each person.

Brief description of the drawings

Fig. 1 is a schematic diagram showing a general configuration of a pain evaluation system 100.

Fig. 2 is a diagram showing functional blocks of the control unit 21 of the pain evaluation system 100 shown in fig. 1.

Fig. 3 is a diagram showing an example of first electrocardiographic waveform data.

Fig. 4 is a diagram showing an example of second electrocardiographic waveform data.

Fig. 5 is a flowchart for explaining the operation of the control unit 21 of the electronic device 20 shown in fig. 1.

Fig. 6 is a flowchart for explaining a first modification of the operation of the control unit 21 of the electronic device 20 shown in fig. 1.

Fig. 7 is a flowchart for explaining a second modification of the operation of the control unit 21 of the electronic device 20 shown in fig. 1.

Fig. 8 is a flowchart for explaining a third modification of the operation of the control unit 21 of the electronic device 20 shown in fig. 1.

Detailed description of the preferred embodiments

(outline of pain evaluation System as embodiment)

The pain evaluation system as an embodiment is a system that determines the degree of pain felt by a user from an electrocardiographic waveform of the user. For example, a user who has a physical problem such as sprain is caused to enter two states: the state of applying a load to the affected part by pressing the affected part with a finger or the like, and the state of not applying a load to the affected part without touching the affected part. The pain evaluation system acquires electrocardiographic waveform data (data including electrocardiographic waveforms of at least two beats) of the user measured by the electrocardiograph in these two states. The pain evaluation system is designed to find an R-wave-to-R-wave interval, i.e., RR interval (or a P-wave-to-P-wave interval, i.e., PP interval) in two adjacent electrocardiographic waveforms from each of the two electrocardiographic waveform data, and determine the degree of pain felt by the user in a state where a load is applied to the affected part based on a comparison of the two RR intervals (or PP intervals).

The inventors found that there was a difference in RR intervals (or PP intervals) between a state in which no load was applied to the affected part and a state in which a load was applied to the affected part, and based on this finding, the degree of pain was successfully scored according to the magnitude of the difference or ratio of the RR intervals (or PP intervals) in each of the two states. Although the perception of pain varies from user to user, in this method, how much the pain of the affected part changes (improves or worsens) for the user can be known according to the magnitude of the difference or ratio of the two RR intervals (or PP intervals) acquired by the same user.

(specific construction of pain evaluation System as embodiment.)

Fig. 1 is a schematic diagram showing a general configuration of a pain evaluation system 100. The pain assessment system 100 shown in fig. 1 includes an electrocardiograph 10, an electronic device 20, and a compression device 30.

The electrocardiograph 10 is a device for measuring an electrocardiographic waveform of a user, and for example, the devices described in patent documents 1 and 2 can be used.

The electronic device 20 is, for example, a smart phone, a tablet terminal, or a personal computer. Specifically, the electronic device 20 includes a control unit 21, a display unit 22, and a communication interface (not shown) for connecting the electrocardiograph 10 and the pressing device 30. The electrocardiograph 10 and the electronic device 20 are configured to communicate by wired communication or wireless communication, and electrocardiographic waveform data (an aggregate of electrocardiographic waveforms of one beat) of the user measured by the electrocardiograph 10 is transmitted to the electronic device 20 through the communication interface.

The control unit 21 includes a CPU (Central processing unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and the like, and performs integrated control of the electronic device 20 according to a program. The ROM of the control section 21 stores programs including a pain evaluation program.

The display unit 22 is a device capable of displaying an image, such as a liquid crystal display panel or an organic EL (electro-luminescence) display panel.

The pressing device 30 is a device for applying a physical load (in other words, stimulation) to a specific part of the user's body (for example, an affected part having a pain feeling). Specifically, the pressing device 30 includes a rod-shaped member, a moving mechanism that moves the rod-shaped member in a longitudinal direction thereof, an operating member for operating the moving mechanism, and a communication interface for communicating with the electronic apparatus 20.

The user performs the following operations: the rod-like member is projected from the projection opening by the moving mechanism by operating the operation member by abutting the projection opening of the rod-like member in the pressing device 30 against the affected part. By this operation, the tip of the rod-like member protruding from the protrusion opening is in a state of pressing the affected part of the user with a constant force, thereby applying a physical load to the affected part. In this way, when the rod-shaped member is driven, information indicating that a load has been applied to the user is transmitted from the pressing device 30 to the electronic apparatus 20. If the rod-shaped member is not driven, information indicating that a load has not been applied to the user is transmitted from the pressing device 30 to the electronic apparatus 20.

(function of control section 21)

Fig. 2 is a diagram showing functional blocks of the control unit 21 of the pain evaluation system 100 shown in fig. 1. The CPU of the control unit 21 performs the functions of the electrocardiographic waveform acquisition unit 21A and the pain determination unit 21B by executing the above-described pain evaluation program stored in the ROM.

The electrocardiographic waveform acquiring unit 21A acquires electrocardiographic waveform data of the user measured by the electrocardiograph 10.

The pain determination unit 21B determines the degree of pain felt by the user in a state where the pressing device 30 is loaded, based on a comparison between the first electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition unit 21A in a state where the pressing device 30 is not loaded on the user's body and the second electrocardiographic waveform data acquired by the electrocardiographic waveform acquisition unit 21A in a state where the pressing device 30 is loaded on the user's body. The pain determination unit 21B, for example, scores the determined pain level, displays the score on the display unit 22, or outputs the score from a speaker, not shown, to notify the user and a person such as a medical staff performing treatment on the user.

Fig. 3 is a diagram showing an example of first electrocardiographic waveform data. The first electrocardiographic waveform data D1 shown in fig. 3 is composed of three electrocardiographic waveforms (electrocardiographic waveform W1, electrocardiographic waveform W2, and electrocardiographic waveform W3) in succession. Each electrocardiographic waveform is composed of a P wave, a Q wave, an R wave, an S wave, a T wave and a U wave. The pain determination unit 21B calculates at least one interval between R-waves of two adjacent electrocardiographic waveforms in the first electrocardiographic waveform data D1. Fig. 3 shows an example of two RR intervals, i.e., RR intervals Δ RR1, which are calculated as the intervals between the R-wave of the electrocardiographic waveform W1 and the R-wave of the electrocardiographic waveform W2, and RR intervals Δ RR2, which are the intervals between the R-wave of the electrocardiographic waveform W2 and the R-wave of the electrocardiographic waveform W3.

Fig. 4 is a diagram showing an example of the second radiowave data. The second electrocardiographic waveform data D2 shown in fig. 4 is composed of three electrocardiographic waveforms (electrocardiographic waveform W4, electrocardiographic waveform W5, and electrocardiographic waveform W6) in succession. Each electrocardiographic waveform is composed of a P wave, a Q wave, an R wave, an S wave, a T wave and a U wave. The pain determination unit 21B calculates at least one interval between R-waves of two adjacent electrocardiographic waveforms in the second electrocardiographic waveform data D2. Fig. 4 shows an example of two RR intervals, i.e., RR intervals Δ RR3, which are calculated as the intervals between the R-wave of the electrocardiographic waveform W4 and the R-wave of the electrocardiographic waveform W5, and RR intervals Δ RR4, which are the intervals between the R-wave of the electrocardiographic waveform W5 and the R-wave of the electrocardiographic waveform W6.

The pain judging section 21B judges the degree of pain of the user by comparing the RR interval of the first electrocardiographic waveform data D1 calculated in the above manner with the RR interval of the second electrocardiographic waveform data D2.

(concrete example of pain judging method)

Fig. 5 is a flowchart for explaining the operation of the control unit 21 of the electronic device 20 shown in fig. 1. The electrocardiographic waveform acquiring portion 21A of the control portion 21 determines whether or not the pressing device 30 is in use (a state in which a physical load is being applied to the body of the user) based on the content of the information received from the pressing device 30 (step S0).

If it is determined that the compression device 30 is not being used (step S0: NO), the electrocardiographic waveform acquisition portion 21A acquires the first electrocardiographic waveform data D1 illustrated in fig. 3 from the electrocardiograph 10 and stores it in the RAM (step S1).

Then, the electrocardiographic waveform acquisition portion 21A determines whether the pressing device 30 is in use, based on the content of the information received from the pressing device 30 (step S2). If it is determined that the compression device 30 is being used (step S2: YES), the electrocardiographic waveform acquisition portion 21A acquires the second electrocardiographic waveform data D2 illustrated in fig. 4 from the electrocardiograph 10 and stores it in the RAM (step S3).

Next, the pain determination unit 21B calculates one RR interval (here, referred to as an RR interval Δ RR1) from the first electrocardiographic waveform data D1 acquired in step S1 (step S4), and calculates one RR interval (here, referred to as an RR interval Δ RR3) from the second electrocardiographic waveform data D2 acquired in step S3 (step S5).

Next, the pain determination unit 21B calculates the absolute value of the difference between the RR interval Δ RR1 calculated in step S4 and the RR interval Δ RR3 calculated in step S5, and determines whether the absolute value exceeds a previously determined threshold TH1 (step S6).

If the affected part is in a state of almost no pain, the difference between the RR intervals DeltaRR 1 and RR intervals DeltaRR 3 is zero, regardless of the measurement error and the fluctuation amount of RR intervals possessed by the user. The threshold TH1 is set to a value obtained by adding a value determined based on a measurement error of the RR interval measured by the electrocardiograph 10 and a fluctuation of the RR interval possessed by the user to zero. Therefore, if the absolute value exceeds the threshold TH1, it can be determined that the RR interval has changed due to pain, and if the absolute value is equal to or less than the threshold TH1, it can be determined that the RR interval has not changed due to pain.

When the absolute value exceeds the threshold TH1 (YES in step S6), the pain determination unit 21B determines that the pain score indicating the degree of pain is, for example, "1" (a value indicating that there is pain) (step S7). When the absolute value is less than or equal to the threshold TH1 (step S6: NO), the pain judging section 21B judges the pain score indicating the degree of pain to be, for example, "0" (a value indicating NO pain) (step S8). Here, the pain score is a numerical value for evaluating pain on two levels of pain and no pain, and the threshold TH1 may be set to a plurality of levels, and the pain score may be increased stepwise each time the absolute value exceeds the threshold of each level.

After the pain determination unit 21B determines the pain score, the determined pain score is displayed on the display unit 22 to notify the user or the like (step S9).

(Effect of the pain evaluation System as an embodiment)

As described above, with the pain evaluation system 100, the degree of pain can be determined from the difference between the RR interval found from the first electrocardiographic waveform data in a state where no physical load is applied to the body and the RR interval found from the second electrocardiographic waveform data in a state where a physical load is applied to the body. The less the pain, the closer the difference is to zero, and the greater the pain, the further away from zero. Therefore, by observing the difference, it can be judged that the pain is improved or the pain is enhanced. As a result, it is useful for diagnosis by a doctor, treatment of a pain part, and the like.

In fig. 5, an average value of the RR interval Δ RR1 and the RR interval Δ RR2 (or an average value of 3 or more RR intervals obtained from the first electrocardiographic waveform data) may be calculated in step S4, and an average value of the RR interval Δ RR3 and the RR interval Δ RR4 (or an average value of 3 or more RR intervals obtained from the second electrocardiographic waveform data) may be calculated in step S5. In this case, in step S6, the value to be compared with the threshold TH1 may be set to the absolute value of the difference between the two average values. In this way, the influence of the fluctuation of the RR interval can be eliminated, and the accuracy of pain determination can be improved.

In addition, if a plurality of RR intervals are calculated in each of step S4 and step S5 in the above manner, the fluctuation (variance) of all RR intervals obtained from the first electrocardiographic waveform data and the fluctuation (variance) of all RR intervals obtained from the second electrocardiographic waveform data may be calculated, and when either of the two variances is equal to or greater than the threshold value, it is determined that pain cannot be determined, and the processing after step S6 is not performed. If the fluctuation of the RR interval is large, the accuracy of the determination of the degree of pain in step S6 may be lowered. Therefore, if the fluctuation is large, the judgment is set to be impossible, and erroneous judgment of the pain level can be prevented.

(first modification of specific example of pain determination method)

Fig. 6 is a flowchart for explaining a first modification of the operation of the control unit 21 of the electronic device 20 shown in fig. 1. The flowchart shown in fig. 6 is the same as fig. 5 except that step S6 is modified to be step S6 a. In fig. 6, the same processes as those in fig. 5 are denoted by the same reference numerals, and the description thereof is omitted.

After step S5, the pain determination unit 21B calculates the ratio of the RR interval Δ RR1 calculated in step S4 to the RR interval Δ RR3 calculated in step S5 (Δ RR1/Δ RR3), and determines whether the absolute value of the difference between the ratio and the reference value determined in advance exceeds a previously determined threshold TH2 (step S6 a).

In the case of the affected part with almost no pain, the ratio of the RR interval Δ RR1 to the RR interval Δ RR3 is "1" in spite of the measurement error and the fluctuation amount of the RR interval of the user. The reference value is set to "1", and the threshold TH2 is set to a value obtained by adding to zero a value determined based on the measurement error of the RR interval measured by the electrocardiograph 10 and the fluctuation of the RR interval possessed by the user. Therefore, if the absolute value exceeds the threshold TH2, it can be determined that the RR interval has changed due to pain, and if the absolute value is equal to or less than the threshold TH2, it can be determined that the RR interval has not changed due to pain.

When the absolute value exceeds the threshold TH2 (YES in step S6a), the pain determination unit 21B determines that the pain score indicating the degree of pain is, for example, "1" (a value indicating that there is pain) (step S7). When the absolute value is less than or equal to the threshold TH2 (step S6 a: NO), the pain judging section 21B judges the pain score indicating the degree of pain to be, for example, "0" (a value indicating NO pain) (step S8). Here, the pain score is a value for evaluating pain on two levels of pain and no pain, and the threshold TH2 may be set to a plurality of levels, and the pain score may be increased in stages each time the absolute value exceeds the threshold of each level.

As described above, according to the operation example shown in fig. 6, the degree of pain is determined from the ratio of the RR interval found from the first electrocardiographic waveform data in the state where no physical load is applied to the body and the RR interval found from the second electrocardiographic waveform data in the state where the physical load is applied to the body. The less pain, the closer the ratio is to 1, and the more pain is away from 1. Therefore, by observing the ratio, it can be judged that the pain is improved or the pain is enhanced. As a result, it is useful for diagnosis by a doctor, treatment of a pain part, and the like.

In fig. 6, the average values of the RR interval Δ RR1 and the RR interval Δ RR2 may be calculated in step S4, and the average values of the RR interval Δ RR3 and the RR interval Δ RR4 may be calculated in step S5. In this case, in step S6a, the value to be compared with the threshold TH2 may be set as the absolute value of the difference between the ratio of the two average values and the reference value. In this way, the influence of the fluctuation of the RR interval can be eliminated, and the accuracy of pain determination can be improved.

(second modification of specific example of pain determination method)

Fig. 7 is a flowchart for explaining a second modification of the operation of the control unit 21 of the electronic device 20 shown in fig. 1. The flowchart shown in fig. 7 is the same as that shown in fig. 5, except that step S6 is modified to be step S21, step S22, and step S23. In fig. 7, the same processes as those in fig. 5 are denoted by the same reference numerals and their descriptions are omitted.

After step S5, the pain determination unit 21B calculates the absolute value Δ D of the difference between the RR interval Δ RR1 and the RR interval Δ RR3 (step S21). Thereafter, the pain determination unit 21B determines whether or not the absolute value Δ D is calculated a plurality of times (for example, 2 times) (step S22). If the absolute value Δ D has not been calculated 2 times (step S22: NO), the pain judging unit 21B shifts the process to step S0. If the absolute value Δ D has been calculated 2 times (YES in step S22), the pain judging section 21B calculates the average of the two absolute values Δ D and judges whether the average exceeds the threshold TH1 (step S23).

The pain determination section 21B performs the process of step S7 if the average value exceeds the threshold TH1 (step S23: YES), and the pain determination section 21B performs the process of step S8 if the average value is equal to or less than the threshold TH1 (step S23: NO).

As described above, according to the operation example shown in fig. 7, since the degree of pain can be determined from a plurality of differences (absolute values Δ D), the determination accuracy can be improved.

In step S23 of fig. 7, the average value of the remaining Δ D may be calculated by dividing the maximum value and the minimum value of the plurality of Δ D, and the calculated average value may be compared with the threshold TH 1. Alternatively, an intermediate value among the plurality of Δ ds may be compared with the threshold TH 1. Thereby, the influence of sudden noise and the like can be eliminated.

In step S23 of fig. 7, each of the plurality of Δ ds may be compared with the threshold TH1, and if the number exceeding the threshold TH1 among the plurality of Δ ds reaches a predetermined number (any value of 1 or more), the process may be shifted to step S7, and if the number exceeding the threshold TH1 among the plurality of Δ ds does not reach the predetermined number (any value of 1 or more), the process may be shifted to step S8.

(third modification of specific example of pain determination method)

Fig. 8 is a flowchart for explaining a third modification of the operation of the control unit 21 of the electronic device 20 shown in fig. 1. The flowchart shown in fig. 8 is the same as that shown in fig. 5, except that step S6 is modified to be step S31, step S32, and step S33. In fig. 8, the same processes as those in fig. 5 are denoted by the same reference numerals and their descriptions are omitted.

After step S5, the pain determination unit 21B calculates a ratio Δ r (Δ RR1/Δ RR3) of the RR interval Δ RR1 to the RR interval Δ RR3 (step S31). Thereafter, the pain determination unit 21B determines whether or not the ratio Δ r has been calculated a plurality of times (for example, 2 times) (step S32). If the comparison value Δ r has not been calculated 2 times (step S32: NO), the pain judging unit 21B shifts the process to step S0. If the comparison value Δ r has been calculated 2 times (step S32: YES), the pain judging section 21B calculates the average of the two ratios Δ r and judges whether the absolute value of the difference between the average and the reference value exceeds the threshold TH2 (step S33).

The pain determination section 21B performs the process of step S7 if the absolute value exceeds the threshold TH2 (step S33: YES), and the pain determination section 21B performs the process of step S8 if the absolute value is equal to or less than the threshold TH2 (step S33: NO).

As described above, according to the operation example shown in fig. 7, since the degree of pain can be determined from a plurality of ratios Δ r, the determination accuracy can be improved.

In step S33 of fig. 8, the average value of the remaining Δ r may be calculated by dividing the maximum value and the minimum value of the plurality of Δ r, and the absolute value of the difference between the average value and the reference value may be compared with the threshold TH 2. Alternatively, the absolute value of the difference between the reference value and the intermediate value of the Δ r may be compared with the threshold TH 2. Thereby, the influence of sudden noise and the like can be eliminated.

In step S33 of fig. 8, the absolute value of the difference between each of the plurality of Δ r values and the reference value may be calculated, and if the number exceeding the threshold TH2 among the plurality of absolute values calculated in the above manner reaches a predetermined number (any of 1 and more), the process may be shifted to step S7, and if the number exceeding the threshold TH2 among the plurality of absolute values does not reach the predetermined number (any of 1 and more), the process may be shifted to step S8.

In the above description, the pain determination unit 21B determines the degree of pain of the user by comparing the RR interval in the state where no load is applied to the user with the RR interval in the state where a load is applied to the user, and similar effects can be obtained by using the PP interval, which is the interval between the P-wave and the P-wave in the two adjacent electrocardiographic waveforms, instead of the RR interval. In addition, a potential difference between a valley of a Q wave and a peak of an R wave in an electrocardiographic waveform may be used instead of the RR interval or the PP interval.

In the above description, the dedicated pressing device 30 is used to apply a load to the user, and as a method of applying a load to the user, for example, a method of pressing an affected part with a finger may be used. By using the pressing device 30, it is possible to apply a load of the same level to the user all the time, and therefore it is possible to accurately determine a change in the degree of pain.

While various embodiments have been described above with reference to the drawings, it is needless to say that the present invention is not limited to the examples. It is obvious to those skilled in the art that various modifications and variations can be made within the scope of the claims and that these modifications and variations also fall within the technical scope of the present invention. In addition, the respective components in the above embodiments may be arbitrarily combined without departing from the scope of the invention.

It should be noted that the present application is based on japanese patent application (japanese patent application 2019-.

Description of the reference numerals

100 pain assessment system

10 electrocardiograph

20 electronic device

30 pressing device

21 control part

21A electrocardiographic waveform acquisition unit

21B pain determination unit

22 display part

D1 first electrocardiographic waveform data

D2 second electrocardiographic waveform data

W1, W2, W3, W4, W5 and W6 electrocardiographic waveforms