Bioelectrode, and intestinal potential measurement apparatus and defecation prediction method using bioelectrode

Abstract

The present invention addresses the problem of providing: a bioelectrode for measuring an intestinal action potential to predict the timing of defecation on the basis of the waveform of the potential; and an intestinal potential measurement apparatus and a defecation prediction method each using the bioelectrode. A bioelectrode (2) has a sheet body (3) including a flexible sheet having a back surface (31) as an adhesive surface (31). The sheet body (3) has: a plurality of electrode pad portions (300, 301) which are arranged so as to be scattered along the large intestinal tract (91), and in which electrodes (4) for acquiring an intestinal potential are exposed on the back surface (31); central device receiving portions (310, 301) which are arranged within an area in which the plurality of electrode pad portions (300, 301) are connected in a ring shape, the central device receiving portions (310, 301) exposing, on an upper surface (30), a plurality of receiving connectors (311) for electrically connecting to connectors (50) of an intestinal electrometer (5) and a plurality of receiving portions (312) for receiving temporary fixation portions (51) of the intestinal electrometer (5); and lead extension portions (320, 321) on which lead wires (322) respectively connecting the plurality of electrode pad portions (300, 301) and the plurality of receiving connectors (311) are fixed.

Description

Bioelectrode, intestinal potential measuring device using the same, and defecation prediction method

[0001] The present invention relates to a technique for measuring an action potential of a living body, and in particular to a bioelectrode for measuring an intestinal potential generated in association with reflex movement of the large intestine, a bowel potential measuring device using the same, and a defecation prediction method.

[0002] Traditionally, caregivers have predicted bowel movements based on past records. Most caregivers typically record bowel movements on a daily basis and make predictions for the coming week based on the records from the most recent week. Even based on the caregiver's experience, accurate bowel movement predictions are difficult to make, as they are easily affected by the care recipient's living environment and health condition, and in many cases, care recipients feel anxious and stressed, especially at night.

[0003] Predictive technology for predicting bowel movements has not yet been established. Currently, the most common methods for understanding bowel movements are diagnostic imaging using X-ray or ultrasound equipment (echo), or sound examination by a doctor using a stethoscope. Predicting bowel movements requires analysis based on continuous measurements over a long period of time. It is difficult to measure continuous data using conventional images and sounds.

[0004] For example, Patent Document 1 (JP 2019-93088 A) describes a wearable intestinal electrometer that collects data over a long period of time using a small, wearable device that can collect intestinal potentials, cardiac potentials, and bowel sounds over a long period of time, and digestive disease diagnosis software that uses intestinal potential, cardiac potential, and heart sound data.

[0005] Furthermore, Patent Document 2 (Japanese Patent No. 3235632) discloses a measuring device for electrogastrograms and electroenterograms that includes at least an electrode fixed to the body surface, an amplifier that amplifies the potential detected by the electrode, a low-pass filter that removes frequency signals other than the stomach potential and intestinal potential amplified by the amplifier, and a recording device, in which the relationship between the frequency of the input signal to the low-pass filter and the phase of the output signal is linear.

[0006] JP 2019-93088 A Japanese Patent No. 3235632 A

[0007] However, the wearable intestinal potential meter and disease diagnosis software of Patent Document 1 use the obtained data of intestinal potential, cardiac potential, and bowel sounds (microphone) to capture the process leading to digestive diseases, particularly constipation, and contribute to the relief of constipation, but are unable to predict bowel movements.

[0008] Furthermore, the electrogastrogram and electroenterogram measuring device of Patent Document 2 uses a low-pass filter to remove noise and acquires frequency signals contained in the stomach potential and intestinal potential, making it possible to grasp the actual activity status of the stomach and intestines from outside the body and obtain information that can be used as a guide for drug administration and treatment, but it is not able to predict bowel movements.

[0009] In view of the above circumstances, the present invention aims to provide a bioelectrode that measures the intestinal action potential and predicts the timing of defecation based on the potential waveform, as well as an intestinal potential measuring device and a defecation prediction method that utilize the same.

[0010] The present invention relates to a bioelectrode comprising a sheet body having a flexible sheet with an adhesive layer on the back surface of the sheet body, the back surface being an adhesive surface to be attached to the abdominal surface of a human body, the sheet body being arranged so as to be scattered along the intestinal tract of the large intestine, the sheet body having a plurality of electrode pad sections on the back surface with electrodes for acquiring intestinal potential exposed, a central device attachment section arranged within a range connecting the plurality of electrode pad sections in a ring shape, the central device attachment section on the front surface with a plurality of connectable terminals electrically connected to connectors of a device and exposes attachable terminals for attaching temporary fixing parts of a device, and lead extension sections to which lead wires are fixed that connect the plurality of electrode pad sections to the plurality of connectable terminals, respectively. A release paper may be attached to the adhesive layer on the back surface of the sheet body.

[0011] The sheet body is attached to the abdominal surface of a human body, and multiple electrodes and a device connected to the multiple electrodes are attached to the abdominal surface. The sheet body can be made of, for example, a flexible sheet made of a flexible material that conforms well to the skin surface and does not cause stress when it comes into contact with the abdominal epidermis of the human body, and that has flexibility, breathability, and water permeability. The sheet body can be composed of, for example, multiple electrode pad portions, a central device attachment portion, and lead extension portions. The sheet body can be configured, for example, so that the electrode pad portions, which are wider than the lead extension portions, are scattered around the central device attachment portion, with thin lead extension portions interposed between them, making it easy for the patient to apply the sheet to the abdominal surface and causing no pain even when worn for long periods of time.

[0012] The sheet body can have an adhesive layer made of a biocompatible adhesive material that is unlikely to cause rashes even when worn for long periods of time, making it highly safe. The sheet body can be formed by sandwiching components such as the electrodes and lead wires between the sheet body and a flexible adhesive sheet. The adhesive sheet can be formed by a flexible core sheet that is smaller in area than the sheet body.

[0013] The plurality of electrode pad portions are attached so that the plurality of electrodes are scattered along the intestinal tract of the large intestine. The plurality of electrode pad portions can be, for example, arranged so as to be scattered along the intestinal tract of the large intestine, with electrodes for acquiring intestinal potential exposed on the back surface. The plurality of electrode pad portions can, for example, ensure a sufficient adhesion surface area around each electrode, preventing unintentional lifting or peeling. The plurality of electrode pad portions can be arranged so as to be scattered along, for example, the cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum. The plurality of electrode pad portions can be arranged so as to be scattered along, for example, the transverse colon, descending colon, sigmoid colon, and rectum. The plurality of electrode pad portions can be arranged so as to be scattered along, for example, the descending colon, sigmoid colon, and rectum.

[0014] The central device mounting section exposes, on the surface of the sheet body, a plurality of connectable terminals electrically connected to the connectors of the electrointestinal electrometer and a mounting portion for mounting the temporary fixing portion of the electrointestinal electrometer. The central device mounting section can be arranged within a range connecting the plurality of electrode pad sections in a ring shape, and exposes, on the surface, a plurality of connectable terminals electrically connected to the connectors of the electrointestinal electrometer and a mounting portion for mounting the temporary fixing portion of the electrointestinal electrometer. The plurality of connectable terminals and the mounting portion can be made of the same part, allowing for both electrical and mechanical connection. Alternatively, the plurality of connectable terminals and the mounting portion can be separate parts.

[0015] The lead extensions connect the electrode pads and the central device mounting portion and are integrated with the sheet body. The lead extensions fix lead wires that electrically connect the electrodes and the corresponding electrodes to the sheet body. Conventional electrometers are unsuitable for wearable devices because their lead wires tend to tangle. However, this new electrometer eliminates the problem of tangled lead wires and allows for safer wear.

[0016] The release paper covers the adhesive surface of the sheet body before use to prevent adhesion. The release paper may be attached to the adhesive surface of the sheet body in an easily releasable manner. The release paper may be attached to the adhesive surface of the sheet body in one sheet or in multiple divided sheets.

[0017] The present invention relates to an intestinal potential measuring device using bioelectrodes, which has connectors connected to each of a plurality of connectable terminals of the central device mounting unit, and a mounting unit mounted on the mounting unit, and an intestinal potential meter detachably mountable on a surface of the central device mounting unit, the intestinal potential meter having a power source, hardware and software driven by the power source, and which acquires an intestinal potential waveform generated in association with intestinal movement using the bioelectrodes and predicts the timing of defecation. The hardware can include a correction unit, a calculation unit, a memory unit, and an output unit.

[0018] The intestinal potential meter extracts autonomic nerve components from the intestinal potential waveform generated in association with intestinal movement acquired by the bioelectrodes, and can also predict the timing of defecation from the LF (Low Frequency) component of the autonomic nerve components.

[0019] The intestinal electrometer can also extract autonomic nerve components from the intestinal potential waveform generated in association with intestinal movement acquired by the bioelectrodes, and predict defecation timing from changes in the power spectra of the LF (low frequency) component, HF (high frequency) component, and / or Mayer wave component. In this case, defecation timing can also be predicted based on the correlation between each component. For example, defecation timing can be predicted from the correlation between changes in the power spectrum of the LF (low frequency) component and changes in the power spectrum of the HF component, which detects the state of breathing, and / or the Mayer wave component, which detects states with large blood pressure fluctuations (e.g., standing, walking, sleeping, eating, etc.). Each of the autonomic nerve components can be analyzed using a fast Fourier transform (FFT) and the power value of each frequency.

[0020] The intestinal potential meter acquires an intestinal potential on the abdominal surface of the human body through the plurality of electrodes, performs arithmetic processing based on the acquired intestinal potential waveform, and predicts and notifies the timing of defecation based on the results of the arithmetic processing. The intestinal potential meter includes, for example, a power supply, and hardware and software driven by the power supply. The hardware may include, for example, a correction unit consisting of an amplifier, a low-pass filter, or the like, that performs waveform amplification processing, waveform correction processing, noise removal processing, waveform shift processing, etc., a CPU, an IC, an LSI, a microcomputer, or other calculation unit, a memory unit such as RAM, ROM, HDD, SSD, or flash memory, and a wireless transmission unit, a wired transmission unit, a display, a speaker, or other output unit.

[0021] The power supply supplies power to the hardware. The power supply can be a primary battery or a secondary battery. By using a secondary battery that can be made smaller and thinner, the outer shape of the electrointestinal meter can be made thin and highly conformable to the skin surface.

[0022] The present invention relates to an intestinal potential measuring device in which the software is equipped with a judgment unit that predicts the timing of defecation by using a judgment algorithm based on the correlation between the acquired intestinal potential waveform and the physical phenomena of intestinal movement and food movement.

[0023] The determination algorithm can be created by elucidating the relationship between changes in intestinal potential and defecation rhythm, based on the results of an analysis of peristaltic movement and changes in intestinal potential on an ultrasound image of the human body, for example.

[0024] In developing the above-mentioned assessment algorithm, we confirmed the correspondence between peristalsis and changes in bowel potential on ultrasound images of the descending colon in the left abdominal region of the human body, which led to the identification of potential changes associated with changes in large intestinal peristalsis. However, when measurements were compared between early morning, when defecation and bowel movements are stable, and daytime, when peristalsis is unlikely to be occurring, differences were observed, but the characteristics of the defecation urge themselves were not clear. Analysis and evaluation of the relationship between bowel potential changes and bowel rhythm was unable to find an algorithm for bowel rhythm using FFT (Fast Fourier Transform) analysis alone. We then introduced the FVS (Flux Vector Splitting) method developed by Kamiya of Aichi Prefectural University, and determined that it captured the characteristics before and after defecation. This led to the development of a assessment algorithm centered on the FVS method. In order to capture the characteristics before and after defecation, it is more effective to capture signals in a lower frequency range than the FFT analysis, and the FVS method is an excellent method for analyzing signals in a lower frequency range that cannot be handled by the FFT.

[0025] The software may employ, for example, a determination algorithm incorporating the FVS method. The determination unit predicts the timing of defecation by analyzing the intestinal potential waveform acquired through the electrodes using a determination algorithm based on the correlation between intestinal movement and the physical phenomenon of food movement. For example, the determination unit uses the determination algorithm incorporating the FVS method to read the ST waves of the descending colon in (1) resting state, (2) segmental movement, (3) peristaltic movement, and (4) pendulum movement in Fig. 4(A) , and distinguishes between (2) segmental movement and (3) peristaltic movement, which are particularly important for predicting the timing of defecation. If (3) peristaltic movement is observed, the determination unit predicts the timing of defecation before it changes to an ST wave during defecation (e.g., 1 hour, 30 minutes, 10 minutes, 5 minutes, etc.). The judgment unit employs, for example, a judgment algorithm incorporating the FVS method, and as shown in Figures 4(A) and (B), reads the change from the ST wave before defecation to the ST wave at the time of defecation, and predicts the timing of defecation before the change to the ST wave at the time of defecation (for example, 1 hour before, 30 minutes before, 10 minutes before, 5 minutes before, etc.).

[0026] The present invention relates to the intestinal potential measuring device, wherein the hardware includes an amplifier for an intestinal potential waveform in the correction unit, and a band-pass filter is integrated with the amplifier.

[0027] The correction unit amplifies, corrects, and filters the intestinal potential waveform, for example. The correction unit includes, for example, an amplifier. The amplifier amplifies the intestinal potential waveform. The amplifier may be integrated with a bandpass filter that corrects the intestinal potential waveform. The amplifier may be a noise-resistant circuit that employs, for example, RLD (Right-Leg Drive) technology and ALS (Adaptive Common-Mode Level Shifting) technology.

[0028] The intestinal potential meter is equipped with, for example, a low-voltage, low-power consumption microcomputer, and the application of active filter technology has enabled optimization of components, thinning, miniaturization, and a lightweight power supply. The intestinal potential meter can have, for example, a sampling signal level of 100 μV, an outer size of 100 mm × 75 mm × 30 mm (or the same volume) or less, and a weight of 250 g or less. More specifically, the outer size can be 59 mm × 58 mm × 30 mm, and a weight of 63.5 g.

[0029] The present invention relates to a defecation prediction method comprising a potential acquisition step of acquiring intestinal potential, a correction step of correcting the acquired intestinal potential waveform, a calculation step of processing the corrected intestinal potential waveform based on the correlation between intestinal movement and the physical phenomenon of food movement, a determination step of predicting defecation timing based on the calculation results, and an output step of outputting a notification of the determined defecation timing.

[0030] The potential acquiring step acquires an intestinal potential. The potential acquiring step acquires an intestinal potential from the plurality of electrodes arranged in a scattered manner along the intestinal tract of the large intestine. The potential acquiring step, for example, continuously acquires an intestinal potential. The potential acquiring step, for example, acquires an intestinal potential for several seconds or several minutes at intervals of several seconds or several minutes. The potential acquiring step can, for example, record the acquired data of the intestinal potential in a memory or transmit it to an external storage unit and record it.

[0031] The correction step corrects the intestinal potential waveform acquired in the potential acquisition step. The correction step, for example, amplifies, corrects, and filters the intestinal potential waveform. The correction step, for example, amplifies the intestinal potential waveform. The correction step, for example, corrects the intestinal potential waveform. The correction step, for example, removes noise using RLD (Right-Leg Drive) technology and ALS (Adaptive Common-Mode Level Shifting) technology. The correction step can, for example, transmit and store the corrected data of the intestinal potential waveform in a memory or flash memory provided in the intestinal potential meter, or in an external memory such as a specific personal computer, database, or big data. The correction step can, for example, transmit and output the file to be sent to an external device in a highly compatible CSV (Comma Separated Value) file.

[0032] The calculation step involves processing the corrected intestinal potential waveform. The calculation step is based on the correlation between intestinal motility and the physical phenomenon of food movement. The calculation step can be performed, for example, by the intestinal electrometer. The calculation step can be performed, for example, by a personal computer, tablet terminal, smartphone, or the like that can communicate with the intestinal electrometer. Tablet terminals such as iPads (registered trademark) are often used in nursing facilities, and an app that enables the calculation step to be installed on the tablet terminal or smartphone can execute the calculation step. The calculation step can be performed, for example, by software that employs a judgment algorithm incorporating the FVS method. The calculation step can be performed, for example, within the intestinal electrometer, or by an external personal computer, tablet terminal, smartphone, server, cloud service, or the like that can communicate with the intestinal electrometer.

[0033] The calculation step performs an analysis using a determination algorithm based on the correlation between the physical phenomena of intestinal movement and food movement on the intestinal potential waveform corrected in the correction step. The calculation step, for example, uses a determination algorithm incorporating the FVS method to read the ST waves of the descending colon in (1) the resting state, (2) segmental movement, (3) peristaltic movement, and (4) pendulum movement in Figure 4(A). The calculation step, for example, employs a determination algorithm incorporating the FVS method to read the change from the ST wave before defecation 820 to the ST wave at the time of defecation 821, as shown in Figures 4(A) and (B).

[0034] The determination step predicts the timing of defecation based on the calculation result of the calculation step. The determination step, for example, analyzes the intestinal potential waveform using a determination algorithm based on the correlation between intestinal movement and the physical phenomenon of food movement to determine the timing of defecation. The determination step, for example, uses a determination algorithm incorporating the FVS method to read the ST waves of the descending colon in (1) resting state, (2) segmental movement, (3) peristaltic movement, and (4) pendulum movement in Figure 4(A), and the determination step distinguishes between (2) segmental movement and (3) peristaltic movement, which are particularly important for predicting the timing of defecation, and, when (3) peristaltic movement is observed, determines the timing of defecation before it changes to an ST wave associated with defecation (for example, 1 hour, 30 minutes, 10 minutes, 5 minutes, etc.).

[0035] In the determination step, for example, the calculation step employs a determination algorithm incorporating the FVS method, reads the change from the ST wave before defecation to the ST wave at the time of defecation as shown in Figures 4(A) and 4(B), and predicts the timing of defecation before the change to the ST wave at the time of defecation (for example, 1 hour before, 30 minutes before, 10 minutes before, 5 minutes before, etc.) The determination step can be performed within the electrointestinal meter, or can be performed by an external personal computer, tablet terminal, smartphone, server, cloud service, etc. that can communicate with the electrointestinal meter.

[0036] The output step outputs a notification of the defecation timing determined in the determination step. The output step, for example, displays a notification image on a display provided in the intestinal electrometer. The output step, for example, generates a notification sound from a speaker provided in the intestinal electrometer. The output step can output the notification by lighting or flashing a lamp provided in the intestinal electrometer.

[0037] The output step can be performed, for example, by a wireless or wired communication unit provided in the intestinal electrometer outputting a notification signal to a personal computer at a nursing facility or a tablet terminal of a caregiver or attendant, etc., and outputting the notification through a display or speaker of the personal computer, tablet terminal, etc. The output step can be performed, for example, by an external personal computer, tablet terminal, smartphone, server, cloud service, etc. that can communicate with the intestinal electrometer.

[0038] The bioelectrode of the present invention, the intestinal potential measuring device using the same, and the defecation prediction method can provide the excellent effect of accurately predicting the timing of defecation.

[0039] (A) A front view showing the bioelectrode 2. (A) A photograph showing the intestinal potential meter 5, (B) A photograph showing the intestinal potential measuring device 10. (A) A front view showing the attachment position of the bioelectrode 2, (B) A photograph showing the attachment position of the bioelectrode 2. (A) A correlation diagram between abdominal echo 830 and intestinal potential 831, (B) A graph of intestinal potential before defecation 820 and during defecation 821 using the FVS method. (A) A configuration diagram showing the defecation prediction system 1, (B) An image diagram showing the defecation prediction system 1. (A) A diagram showing a list display screen 104a of the smartphone 100, (B) A diagram showing a detailed display and input screen 104b of the smartphone 100. Flowchart of defecation prediction method 8. Graphs of measurements taken with the electroenterometer on a person who has not undergone surgery. (A) A correlation graph of power values ​​between cardiac cycle and intestinal cycle in the LF frequency band, (B) A correlation graph of power values ​​between cardiac cycle and intestinal cycle in the HF frequency band. (B) A correlation graph of power values ​​between "electroenterometer" power values ​​at the frequency of interstitial cells of Cajal (ICC) (0.5 Hz: 2 seconds) and power values ​​at the same frequency on an electrocardiogram. (A) A comparison of power values, (B) Power values ​​versus time. A correlation graph between the power value at a frequency (0.5-1.0 Hz) that includes the heart rate and the power value at a frequency (0.5-1.0 Hz) of the potential near the descending colon measured with an "electrointestinal meter."

[0040] Hereinafter, a bioelectrode according to the present embodiment, an intestinal potential measuring device using the same, and a defecation prediction method will be specifically described with reference to the drawings. In particular, this embodiment is a wearable bioelectrode that does not have exposed lead wires and has an intestinal potential meter mounted thereon.

[0041] As shown in Figures 1, 2(B) and 3(A) and (B), the bioelectrode 2 has a sheet body 3, for example, in which an adhesive layer 31 is provided on the back surface 31 of the front and back surfaces 30 and 31 of a flexible sheet, and the sheet body 3 has an adhesive surface 31 that is attached to the abdominal surface 90 of the human body 9, and the sheet body 3 is arranged so as to be scattered along the intestinal tract 91 of the large intestine, and has a plurality of electrode pad portions 300 and 301 on the back surface 31 of which electrodes 4 for acquiring intestinal potential are exposed, and a loop that connects the plurality of electrode pad portions 300 and 301 in a ring shape. The sheet body 3 has a central device mounting section 310 on the surface 30 of which are exposed a plurality of connectable terminals 311 that are electrically connected to the connectors 50 of the intestinal electrometer 5, and a central device mounting section 312 on which is mounted a temporary fixing section 51 of the intestinal electrometer 5, and lead extension sections 320, 321 to which are fixed lead wires 322, 323 that respectively connect the plurality of electrode pad sections 300, 301 and the plurality of connectable terminals 311, and a release paper 33 is attached to the adhesive layer 31 on the back surface 31 of the sheet body 3.

[0042] The flexible sheet may be, for example, a nonwoven fabric, an elastic cotton fabric, a knitted resin fabric, a porous film, a moisture-permeable film, a foamed resin film, or a foam tape. The bioelectrode may be, for example, a disposable one. The adhesive layer may be a flexible and hypoallergenic adhesive.

[0043] The plurality of electrode pad portions 300, 301 are arranged, for example, at three locations that can be scattered along the descending colon 92, the sigmoid colon 93, and the rectum 94. Each of the three electrode pad portions 300, 301 has a diameter, for example, two to three times the diameter of the electrode 4 arranged at the center of the respective electrode pad portions 300, 301. The sheet main body 3 having the three electrode pad portions 300, 301 comprises, for example, two electrode pad portions 300 arranged at a 180° angle around the central device mounting portion 310 and connected by a short lead extension portion 320, and one earth electrode pad portion 301 arranged at a 90° angle from the two electrode pad portions 300 and connected by a long lead extension portion 321. The central device mounting portion 310 has exposure holes 313 drilled therein that correspond to the plurality of connector terminals 311 and mounting portions 312.

[0044] The central device mounting section 310 has the exposure hole 313 (connectable terminals 311 and mounted portions 312) disposed, for example, inside an imaginary circle of diameter 302 passing through the three electrode pad sections 300, 301. The multiple connectable terminals 311, mounted portions 312, lead wires 322, long lead wires 323, and electrodes 4 are integrated, for example, into a reinforcing core sheet 32 ​​that is flexible and has a shape roughly similar to but a sufficiently smaller area than the sheet main body 3. The core sheet 32 ​​can be, for example, attached to either the front or back surface 30, 31 of the sheet main body 3. The core sheet 32 ​​has, for example, an adhesive layer on both its front and back surfaces.

[0045] For example, the connectable terminals 311, the attached portions 312, the lead wires 322, and the long lead wires 323 are adhesively fixed to the surface of the core sheet 32. For example, the core sheet 32 ​​has electrode holes drilled in three locations on the electrodes 4, and is adhesively fixed so that the electrodes 4 are exposed on the back side from each electrode hole. The front surface of the core sheet 32 ​​is, for example, attached to the back surface 31 of the sheet main body 3 to be integrated. The back surfaces of the electrodes 4 are covered by the back surfaces of the electrode pad portions 300, 301. The lead wires 322, 323 are sandwiched and covered between the back surface 31 of the sheet main body 3 and the front surface of the core sheet 32. The back surfaces of the connectable terminals 311 and the attached portions 312 are covered by the core sheet 32. The connectable terminals 311 and the attached portions 312 are exposed on the surface 30 of the sheet main body 3 from the exposure holes 313.

[0046] The core sheet 32 ​​may have an adhesive layer 31 provided on a part or the entire surface of one side that is adhered to the human body 9, and the connectable terminals 311, the attached portion 312, the lead wires 322, the long lead wires 323, and the electrodes 4 may be adhered and fixed to the other side with a flexible adhesive. The core sheet 32 ​​may not have an adhesive layer 31 provided on the front or back sides, and may have the connectable terminals 311, the attached portion 312, the lead wires 322, the long lead wires 323, and the electrodes 4 adhered and fixed to one side with a flexible adhesive.

[0047] The lead wires 322, 323 of the bioelectrode 2 are sandwiched between the sheet main body 3 and the core sheet 32. The connected terminal 311 and the attached portion 312 are supported by the core sheet 32. The electrode 4 is supported by the sheet main body 3. The core sheet 32 ​​may have an adhesive layer 31 only on the surface that joins with the sheet main body 3, for example. The core sheet 32 ​​may have an adhesive layer 31 only on the surface that adheres to the human body 9, for example. The core sheet 32 ​​may have no adhesive layers on either side, for example. When the core sheet 32 ​​does not have an adhesive layer on the surface that contacts the human body 9, it is adhered to the skin surface of the human body 9 only by the adhesive layer 31 of the sheet main body 3.

[0048] A release paper 33 is attached to the adhesive layers of the main sheet body 3 and the core sheet 32. The release paper 33 may be, for example, one-side resin-coated paper, a resin film, or the like.

[0049] The bioelectrode 2 has a connector 50 and a temporary fixing portion 51 of the gut potential meter 5 detachably attached to the connector 311 and the attachment portion 312 exposed on the surface 30 of the central device attachment portion 310. The connector 50 electrically connects to the lead wire 322 and the long lead wire 323, respectively. The temporary fixing portion 51 mechanically attaches the gut potential meter 5 to the bioelectrode 2. The connector 50 and the connector 311, and the temporary fixing portion 51 and the attachment portion 312, can be an integrated attachment / detachment mechanism that is electrically and mechanically detachable as a whole, such as a combination of a convex metal part and a concave metal part of a snap button or a combination of a power outlet and a plug. The bioelectrode 2 can, for example, have a vital sensor (not shown) separate from the electrode 4 integrated into the sheet main body 3 to acquire and output vital data other than gut potential, such as pulse, blood pressure, and body temperature.

[0050] The intestinal electrometer 5 has a housing 52 with an outer size of 59 mm × 58 mm × 30 mm or less and a weight of 63.5 g or less. The connector 50 and temporary fixing portion 51 are exposed on the back surface of the housing 52. The housing 52 has, for example, at least a power supply 53, a correction unit 60, a calculation unit 61, a storage unit 62, and an output unit 63. The housing 52 is provided such that, for example, a power switch 54 is exposed to the outside. The power switch 54 is, for example, dedicated to turning the power on, and the power off operation can be performed remotely via wireless communication from a personal computer, tablet terminal, smartphone, or the like outside the housing 52.

[0051] The power source 53 may be, for example, a thin rechargeable secondary battery. The power source 53 may, for example, have a charging plug socket in the housing 52 and a waterproof cap for the socket. The power source 53 may, for example, have a wireless charging unit including a power receiving coil built into the housing 52. The wireless charging unit may eliminate the need for a charging socket, and the housing 52 may be sealed. The power switch 54 may, for example, be dedicated to turning the power on and may be turned off when it detects the start of charging. The power switch 54 may, for example, be built into the housing 52 and may be turned on when it detects the end of charging and turned off when it detects the start of charging.

[0052] The correction unit 60 corrects the intestinal potential acquired through the electrodes 4 and the lead wires 322, 323. The correction unit 60 includes, for example, an amplifier 600, which is integrated with a band-pass filter 601. The amplifier 600 can be an amplification circuit that enhances waveform values ​​using, for example, RLD (Right-Leg Drive) technology. The band-pass filter 601 can be a shift circuit that shifts the waveform using ALS (Adaptive Common-Mode Level Shifting) technology. The correction unit 60 can include circuits for waveform correction processing, noise removal processing, waveform amplification processing, waveform shift processing, etc.

[0053] The calculation unit 61 may be, for example, a CPU. It may also be an IC, an LSI, a microcomputer, or other integrated circuit. The storage unit 62 may be, for example, a RAM, a ROM, an SSD, an HDD, a flash memory, or the like. It may include a transmission unit and communicate with an external storage device. The output unit 63 may be, for example, a wireless or wired transmission unit 63 that transmits signals to an external computer, tablet terminal, or the like. The transmission unit 63 wirelessly outputs the intestinal potential information corrected by the correction unit 60, for example, every few seconds (intermittently). The transmission unit 63 communicates using a communication standard such as Wi-Fi, Bluetooth (registered trademark), or other standards. The transmission unit 63 wirelessly outputs the intestinal potential information, for example, continuously. The intestinal potential information may include, for example, measurement time information. The output intestinal potential information may include, for example, ID information assigned to each individual intestinal potential meter 5. The output unit 63 can be, for example, a GPU that is provided with a display integrally in the housing 52 and displays an image on the display.

[0054] The intestinal potential measuring device 10 of this invention is a wearable intestinal potential measuring device 10 in which the intestinal potential meter 5 is detachably attached to the bioelectrode 2, and the bioelectrode 2 is a disposable type. As shown in Figures 1 to 3, the release paper 33 of the intestinal potential measuring device 10 is peeled off, and the three electrodes 4 are attached to an abdominal surface 90 of a human body 9 so that they are positioned along an intestinal tract 91 of the large intestine, for example, at three points (three solid-line circles in Figure 3(A)) corresponding to a midpoint of the descending colon 92, a portion of the sigmoid colon 93 closer to the descending colon 92, and a portion of the sigmoid colon 93 closer to the rectum 94.

[0055] The intestinal potential measuring device 10 is incorporated into, for example, an intestinal potential measuring system 1 shown in Figures 4 to 7, thereby enabling the defecation prediction method 8 of the present invention to be realized. As shown in Figure 5, for example, the intestinal potential measuring system 1 includes a system CPU 100, a system memory 101, an audio output device 102, a system communication interface 103, a display controller 104, an input device interface 105, an external storage device 106, an external storage medium slot 107, and a bus 108 connecting them.

[0056] The system CPU 100 sequentially performs, for example, a potential acquisition step 80, a correction step 81, a calculation step 82, a determination step 83, and an output step 84 of the control step 8 of the defecation prediction method of the present invention. The potential acquisition step 80 and the correction step 81 can be performed by the correction unit 60 of the intestinal electrometer 5.

[0057] (Potential Acquisition Step 80) The system CPU 100 receives, for example, via the system communication interface 103, intestinal potential information wirelessly output by the intestinal potential meter 5 of the intestinal potential measuring device 10. The intestinal potential information is accompanied by, for example, measurement time information and ID information of the intestinal potential meter 5. Upon receiving the intestinal potential information, the system CPU 100 can transmit and store, for example, the intestinal potential information, measurement time information, and ID information of the intestinal potential meter 5 to the external storage device 106. Personal information identifying the individual subject 9 on whom the intestinal potential meter 5 is attached is stored in advance in the external storage device 106. Various care data can be linked to the personal information.

[0058] (Correction Step 81) For example, if the acquired intestinal potential information has not been corrected, the system CPU 100 can amplify the waveform value using RLD (Right-Leg Drive) technology. Furthermore, for example, the system CPU 100 can shift the waveform using ALS (Adaptive Common-Mode Level Shifting) technology. The system CPU 100 transmits and stores the corrected intestinal potential waveform information in the external storage device 106.

[0059] (Calculation Step 82) In the calculation step 82, the system CPU 100, for example, analyzes the intestinal potential waveform using a determination algorithm based on the correlation between the physical phenomena of intestinal movement and food movement to determine the timing of defecation. For example, the system CPU 100 uses a determination algorithm incorporating the FVS method to read the ST waves of the descending colon in (1) the resting state, (2) segmental movement, (3) peristaltic movement, and (4) pendulum movement shown in Figure 4(A) of the corrected intestinal potential waveform information. The system CPU 100 employs a determination algorithm incorporating the FVS method to read the change from the ST wave before defecation to the ST wave during defecation, as shown in Figures 4(A) and 4(B). Furthermore, in this calculation step 82 or the correction step 81, the acquired intestinal potential waveform data can be analyzed using a fast Fourier transform (FFT) and the power value of each frequency.

[0060] (Determination step 83) The system CPU 100 predicts the timing of defecation, for example, based on the calculation result of the calculation step 82. For example, in the calculation step 82, the system CPU 100 reads the ST waves of (1) resting state, (2) segmental movement, (3) peristaltic movement, and (4) pendulum movement of the descending colon in Fig. 4(A) by a determination algorithm incorporating the FVS method, and then in the determination step 83, distinguishes between (2) segmental movement and (3) peristaltic movement, which are particularly important for predicting the timing of defecation, and when the (3) peristaltic movement is indicated, predicts and determines the timing of defecation before it changes to an ST wave at the time of defecation (for example, 1 hour before, 30 minutes before, 10 minutes before, 5 minutes before, etc.). In the judgment step 83, for example, a judgment algorithm incorporating the FVS method is adopted in the calculation step 82, and as shown in Figures 4(A) and (B), the change from the ST wave before defecation to the ST wave at the time of defecation is read, and in the judgment step 83, the timing of defecation is predicted before the change to the ST wave at the time of defecation (for example, 1 hour before, 30 minutes before, 10 minutes before, 5 minutes before, etc.).

[0061] In addition, this judgment step 83 can extract and analyze / judge autonomic nervous components (LF, HF, Mayer waves), and can predict the timing of defecation by focusing particularly on the LF (low frequency) component of the autonomic nervous system. Specifically, the power value of the LF component is detected, and then summed over an 8-minute period to create waveform data. This corrected data is used to reduce noise components such as respiration, body movement, and blood pressure fluctuations. The lowest level in the corrected data is estimated (methods that combine averaging, waveform recognition, and amplitude duration methods, similar to measuring potential from minute electroencephalogram waveforms, were considered), and the portion of the data that is higher than twice the power value of that level is selected. This selected value is not a sharp waveform that combines body movement, but rather a slightly continuous, mountain-shaped waveform (a waveform that continuously captures the series of activities from the defecation urge to defecation), allowing the timing of defecation to be predicted.

[0062] (Output step 84) The system CPU 100 outputs, for example, a notification of the defecation timing determined in the determination step 83. The output step can output a notification signal to a personal computer at the nursing facility or a tablet terminal of a caregiver or attendant via the system communication interface 103, and output the notification through a display or speaker of the personal computer, tablet terminal, or the like.

[0063] The system CPU 100, for example, associates data acquired or acquired by arithmetic processing at each stage of the control process 8 with personal information that identifies the subject 9, and transmits and stores the data to the external storage device 106. The stored information is stored, for example, in a highly compatible CSV file. The stored information and notification information can be recorded, for example, in a network cloud 109 connected via the system communication interface 103.

[0064] The items of the stored information and notification information can be, for example, information acquired during the processing steps of control step 8 shown in Fig. 7. For example, intestinal potential information acquired by the electrode 4 in the potential acquisition step 80. For example, intestinal potential corrected information obtained by correcting the intestinal potential information obtained in the potential acquisition step 80 in the correction step 81. For example, intestinal potential calculation processing information obtained by performing calculation processing on the intestinal potential corrected information in the calculation step 82. For example, defecation timing information obtained by determining defecation timing based on the intestinal potential calculation processing information in the judgment step 83. For example, defecation timing notification information notified based on the defecation timing information in output step 84. The intestinal potential information, intestinal potential corrected information, intestinal potential calculation processing information, defecation timing information and defecation timing notification information can all be linked to personal information that identifies the individual subject 9 and information on the time the intestinal potential information was acquired.

[0065] The items of information stored in the external storage device 106 or the network cloud 109 include, for example, the name of the subject 9, the ID of the subject 9, or the room number of a care facility or the like, which are recorded as information for identifying the subject 9 by inputting it into a smartphone, tablet terminal, or the like of a caregiver. As basic information on defecation timing, for example, the predicted defecation time (time period at 20-minute intervals), the status of intestinal activity, and the judgment results of (1) resting state, (2) segmental movement, (3) peristaltic movement, and (4) pendulum movement in Figure 4(A) are stored, which are linked to the ID of the subject 9 or the room number of a care facility or the like.

[0066] The items of information stored in the external storage device 106 or the network cloud 109 include, for example, information input by a caregiver, such as the date and time of the subject's 9 defecation, the urge to defecate (yes, no), the condition of the stool (small, hard, slightly hard, normal, soft, muddy, watery), the amount of stool (large, medium, small, with gas), medication (yes, no), the name of the medication (laxative), and the special note "defecated after being spoken to," which are recorded linked to information that identifies the subject 9.

[0067] Furthermore, the information stored in the external storage device 106 can be checked in real time, for example, on various terminals. For example, as shown in Figures 5(B) and 6(A), when a caregiver downloads a monitoring app and launches the app on the smartphone 100, the predicted defecation timings of multiple subjects 9 are displayed as pictograms in a simple list format when the caregiver looks at the display 104. The display layout and pictogram images of each screen can be stored in the app. The list screen 104a displays the name of the caregiver in charge at the top. The list screen 104a allows the caregiver to check the defecation timings of more subjects 9 in real time by scrolling.

[0068] The display of the predicted status of defecation timing on the smartphone 100 can be expanded to multiple more detailed pages, as shown in FIG. 6B . For example, when a display field for one subject 9 on the list screen 104a is tapped, a detailed history screen 104b for the selected subject 9 is displayed. The detailed history screen 104b displays, for example, the name, room number, date of birth, age, gender, and level of care required of the selected subject 9 at the top of the screen. The detailed history screen 104b displays, for example, the current defecation timing in the middle of the screen using words ("It's almost time"), predicted time (at 20-minute intervals), pictograms, and the words "Defecation is near," for example. The detailed history screen 104b displays, for example, defecation history at the bottom of the screen. For example, the display shows the last bowel movement 10 hours ago, with a record of the bowel movement status, such as "hard" or "small amount," and further below, a list of bowel movements prior to the last time is displayed along with information such as the date and time, stool condition, and amount of stool.

[0069] When the smartphone 100 notifies the caregiver that it is time to defecate, a notification / input screen 104c is displayed and a voice message is sent to notify the caregiver that it is time to defecate. The caregiver, upon receiving the notification, provides defecation care and then selects the record button on the notification / input screen 104c to record information such as the date and time of defecation, urge (yes / no), stool condition (small, hard, slightly hard, normal, soft, muddy, watery), and stool volume (large, medium, small, gassy). Further scrolling reveals a medication and other record button, allowing the caregiver to input medication (yes / no), drug name (laxative), and special notes such as "defecated after speaking to the caregiver." By tapping the register button, the input information is sent to and stored in the external storage device 106 or the network cloud 109. The information input by the caregiver is also displayed and can be confirmed on the list screen 104a and the detailed history screen 104b. The stored data can be stored, for example, in the care record software / cloud service 109.

[0070] [Purpose of the Experiment] This experiment was conducted to visualize bowel movement predictions in healthy adults (aged 19-21) using an electroenterometer. [Experimental Method] Subjects: Healthy adults willing to participate in the study were selected. Electroenterometer electrodes were attached to three abdominal locations as shown in Figure 8. Measurements were conducted over a seven-hour period, from morning through afternoon, including lunch. Subjects were instructed to record daily events during the measurement, such as eating, drinking, urination, defecation, rest, and exercise, on a sheet. [Analysis] The potential data obtained from the electroenterometer was subjected to a fast Fourier transform to calculate power spectra every 10 minutes. Analysis was performed using four frequencies: intermediate frequency component (LF 0.048 Hz), blood pressure signal (Mayer Wave 0.097 Hz), parasympathetic nervous system (HF 7.314 Hz), and sympathetic nervous system (LF / HF).

[0071] [Results] Of the 110 participants, 21 (3 of whom were male) had a bowel movement during the measurement. Therefore, analysis focused on the 21 subjects who had a bowel movement. Regarding daily bowel movements, 10 subjects had a bowel movement every day, 9 had a bowel movement every other day, and 2 had a bowel movement twice a week. The average measurement time was 428 minutes (range, 376-506 minutes). Figure 9 shows the measurement graphs of healthy adults aged 19-21 years among the 21 subjects who had a bowel movement. Figure 9(A) shows the graph of a subject who had regular changes in parasympathetic nervous activity at approximately 4-minute intervals before defecation. Similar changes were observed in 9 subjects. Figure 9(B) shows the graph of a subject who had regular changes in parasympathetic nervous activity at approximately 8-minute intervals before defecation. Similar changes were observed in 5 subjects. Figure 9(C) shows the graph of a subject taking an antidepressant, showing regular changes in parasympathetic nervous activity. [Discussion] Before defecation, the gastrocolic reflex moves stool from the colon to the rectum, temporarily causing the parasympathetic nervous system to become dominant. Although bowel movements vary from person to person, it is believed that capturing these changes can lead to defecation behavior. Furthermore, if people who wear diapers can be guided to defecate in the toilet, it is believed that this could contribute to the promotion of diaper potty training.

[0072] [Purpose of the Experiment] This experiment was conducted to visualize bowel peristalsis associated with defecation in a patient who had undergone stoma closure surgery. [Experimental Method] Subject: A male in his 40s who had a stoma created for rectal carcinoid tumors for four months and whose stoma had been closed for over six years. In 2016, he underwent robotic surgery for rectal carcinoid tumors, creating a stoma in his left lower abdomen. The stoma was closed four months later. Despite the six-year history of stoma closure, he continues to use disposable diapers due to concerns about fecal incontinence due to frequent bowel movements and occasional absence of bowel urges. The subject had the electrodes of a bowel potential meter attached to three abdominal locations (see Figure 8) and was asked to wear the meter for 24 hours twice (February and June). The meter was removed during bathing, and the electrodes were reattached after bathing to begin measurements. Life events were recorded as information for analyzing the stoma. The analysis focused on the autonomic nervous system (LF, Mayer wave, HF, LF / HF).

[0073] [Results] The first measurement showed five defecations (two of which were accompanied by a defecation urge), and the second measurement showed five defecations (two of which were accompanied by a defecation urge). The stool quality was rated 5-6 or 1-2 on the Bristol scale. When there was no defecation urge, this was due to a preventive defecation to avoid soiling the disposable diaper or to prevent fecal incontinence in preparation for the next scheduled defecation. Figure 10 shows the graph of the first electrointestinal measurement ((a) indicates defecation urge, (b) indicates no defecation urge), and Figure 11 shows the graph of the second electrointestinal measurement ((a) indicates defecation urge, (b) indicates no defecation urge). Figure 12 also shows the graph of the electrointestinal measurement of a non-surgical subject. [Discussion] When examining the power spectrum of the autonomic nervous system's low frequency (LF), it is believed that the strength of the power varies depending on the individual and their physical condition on that day. However, during defecation, a waveform exhibiting unique changes appears 20-30 minutes before defecation. Even in subjects who have had a rectum resection, unique waveforms are observed when they have a defecation urge.

[0074] Because intestinal activity is stimulated by the parasympathetic nervous system and inhibited by the sympathetic nervous system, the power values ​​of the LF component, HF component, Mayer wave component, and LF / HF component obtained from heart rate variability were compared with the potential of the descending colon with the same frequency components (power spectrum). This was done by determining the correlation between the power values ​​of each power spectrum per second. As a result, as shown in Figures 13(A) and 13(B), a negative correlation was observed between the LF component and HF component obtained from the R-R interval variability of the electrocardiogram and the power values ​​of the LF component (same frequency as the electrocardiogram) and HF component (same frequency as the electrocardiogram) obtained from the "intestinal electrometer" with a delay of approximately 480 seconds (approximately 8 minutes: 4 analysis times, with 120 seconds being one analysis time). This indicates that intestinal activity is stimulated by the parasympathetic nervous system (vagus nerve) and inhibited by the sympathetic nervous system, confirming that the potential measured by the "intestinal electrometer" according to this embodiment originates from the "intestine."

[0075] 14(A) and 14(B), when the power value of the "gut electrometer" at the frequency (0.5 Hz: 2 seconds) of interstitial cells of Cajal (ICC), which are pacemaker cells in the digestive tract, was correlated with the power value of the electrocardiogram at the same frequency, a strong negative correlation was observed between the two with a delay of approximately 240 seconds. This means that the closer the frequency is to the ICC cells, the more strongly the "gut action potential" is influenced by the autonomic nervous system, and therefore it was possible to confirm from these results that the potential measured by the "gut electrometer" in this embodiment is derived from the "gut."

[0076] 15, a positive correlation is observed between the power value at a frequency (0.5-1.0 Hz) that includes the heart rate and the power value at the frequency (0.5-1.0 Hz) of the potential near the descending colon measured by the "enteric potential meter," indicating that an electrocardiogram is also present near the descending colon. This means that the "enteric potential meter" according to this embodiment can measure not only the "enteric potential" but also the "cardiac potential," and can be said to function as an "electrometer."

[0077] The bioelectrode of the present invention, the intestinal potential measuring device using the same, and the defecation prediction method can be used for nursing, assistance, and care in nursing facilities, hospitals, ordinary homes, etc., management of long-distance driving in the transportation industry, diaper management, and space suit control.

[0078] 1 Intestinal potential measurement system 100 System CPU (personal computer, smartphone) 101 System memory 102 Audio output device 103 System communication interface 104 Display controller (display) 104a List screen 104b Detailed history screen 104c Notification / input screen 105 Input device interface 106 External storage device 107 External storage medium slot 108 Bus 109 Network cloud 10 Intestinal potential measurement device 2 Bioelectrode 3 Sheet body (flexible sheet) 30 Surface of sheet body 3 31 Back side of sheet body 3 (adhesive layer, adhesive surface) 32 Concentric sheet 33 Release paper 300 Electrode pad section 301 Earth electrode pad section 302 Imaginary circle with diameter (302) 310 Central device attachment section 311 Connected terminal 312: The attachment portion 313: The exposure hole 320: The lead extension portion 321: The long lead extension portion 322: The lead wire 323: The long lead wire 4: The electrode for acquiring intestinal potential 5: The intestinal potential meter 50: The connector 51: The temporary fixing portion 52: The housing 53: The power supply 54: The power switch 6: Hardware 60: The correction portion 600: The amplifier 601: The band pass filter 61: The calculation portion 62: The memory portion 63: The output portion (transmitter, display) 7: Software 70: The judgment portion 8: Control step (defecation prediction method) 80: The potential acquisition step 81: The correction step 82: The calculation step 820: The intestinal potential waveform before defecation 821: The intestinal potential waveform at the time of defecation 83: The judgment step 830: The abdominal ultrasound image 831: The Intestinal potential waveform 84 Output process 9 Human body (subject) 90 Abdominal surface91 Large intestine 92 Descending colon 93 Sigmoid colon 94 Rectum

Claims

1. A bioelectrode comprising a sheet body having an adhesive layer on the back of a flexible sheet, the back being an adhesive surface to be attached to the abdominal surface of a human body, the sheet body having: a plurality of electrode pad sections which are arranged so as to be scattered along the intestinal tract of the large intestine, with electrodes for obtaining an intestinal potential exposed on the back surface; a central device attachment section which is arranged within a range connecting the plurality of electrode pad sections in a ring shape, and which has exposed on the front surface a plurality of connectable terminals which are electrically connected to the connectors of an intestinal potential meter and an attachable section for attaching a temporary fixing section of the intestinal potential meter; and lead extension sections to which lead wires which respectively connect the plurality of electrode pad sections and the plurality of connectable terminals are fixed.

2. An intestinal potential measuring device using a bioelectrode as described in claim 1, which has connectors connected to each of the multiple connectable terminals of the central device attachment part, and attachment parts that are attached to the attachment parts, and which has an intestinal potential meter that can be detachably attached to the surface of the central device attachment part, and which has a power source, hardware and software that are driven by the power source, and which acquires intestinal potential waveforms generated in conjunction with intestinal movement using the bioelectrode and predicts the timing of defecation.

3. The intestinal potential measuring device according to claim 2, wherein the intestinal potential meter extracts autonomic nerve components from the intestinal potential waveform generated in association with intestinal movement acquired by the bioelectrodes, and predicts the timing of defecation from the LF (Low Frequency) component of the autonomic nerve components.

4. An intestinal potential measuring device as claimed in claim 2, wherein the software comprises a judgment section for predicting the timing of defecation by applying a judgment algorithm based on the correlation between the physical phenomena of intestinal movement and food movement to the acquired intestinal potential waveform.

5. The intestinal potential measuring device according to claim 2, wherein said hardware includes an amplifier for the intestinal potential waveform in said correction section, and said amplifier is integrated with a bandpass filter.

6. A defecation prediction method comprising: a potential acquisition step for acquiring intestinal potential; a correction step for correcting the acquired intestinal potential waveform; a calculation step for processing the corrected intestinal potential waveform based on the correlation between intestinal movement and the physical phenomenon of food movement; a determination step for predicting defecation timing based on the calculation result; and an output step for outputting a notification of the determined defecation timing.

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