Urine electrical property measuring device, urine electrical property measuring system, and urine electrical property measuring method

Abstract

Provided are a urine electrical property measuring device, a urine electrical property measuring system, and a urine electrical property measuring method capable of continuously measuring the electrical properties of urine.　This urine electrical property measuring device comprises: a dripping portion for dripping urine; a retaining portion for temporarily retaining the dripped urine; and a measuring portion for measuring the electrical properties of the urine retained in the retaining portion.

Description

Apparatus for measuring electrical properties of urine, system for measuring electrical properties of urine, and method for measuring electrical properties of urine

[0001] The present disclosure relates to an apparatus for measuring electrical characteristics of urine, a system for measuring electrical characteristics of urine, and a method for measuring electrical characteristics of urine.

[0002] For patients who are unable to excrete urine due to illness or surgery, a urinary catheter can be inserted through the urethra into the bladder, and the urine excreted through the catheter can be collected in a urine drainage bag. The patient's condition can be confirmed by examining the components of the excreted urine. For example, it is known that the electrical properties of urine (conductivity and resistivity) correlate with urine osmotic pressure (chloride ions), and understanding the electrical properties of urine is useful for assessing renal function and screening for diseases.

[0003] Patent Document 1 discloses a urine testing device that includes a measurement unit, a transport unit, and an information processing unit, where the transport unit has a transport path, a sample rack holding multiple sample containers is transported on the transport path, and a nozzle provided in the measurement unit aspirates the sample from the sample container to measure the sample.

[0004] JP 2012-32353 A

[0005] However, when using a urine testing device such as that disclosed in Patent Document 1 on a patient who is unable to excrete urine from their body, urine stored in a urine drainage bag must be collected and placed in a specimen container, necessitating urine sampling each time a test is performed. This makes it impossible to continuously measure the electrical properties of urine excreted from the patient's body. Furthermore, even if urine collected in a urine drainage bag is collected, it is not suitable for measuring changes in the electrical properties of fresh urine over time.

[0006] The present disclosure has been made in consideration of the above circumstances, and aims to provide a urine electrical characteristics measuring device, a urine electrical characteristics measuring system, and a urine electrical characteristics measuring method that can continuously measure the electrical characteristics of urine.

[0007] (1) A device for measuring electrical characteristics of urine according to the present disclosure includes a dripping unit for dripping urine, a retention unit for temporarily retaining the dripped urine, and a measurement unit for measuring the electrical characteristics of the urine retained in the retention unit. Here, embodiments of the present disclosure include: (2) the device for measuring electrical characteristics of urine according to (1) above includes a plurality of first electrodes that continuously contact the urine retained in the retention unit. (3) the device for measuring electrical characteristics of urine according to (2) above includes a plurality of second electrodes that contact the plurality of first electrodes, respectively, and the measurement unit measures the electrical characteristics of the urine by passing current through each of the second electrodes. (4) the device for measuring electrical characteristics of urine according to (3) above includes a spring member for reinforcing the contact between the first electrodes and the second electrodes. (5) In any one of the devices for measuring electrical characteristics of urine according to (1) to (4) above, the retention unit includes a cylindrical body and a porous body that is disposed within the cylindrical body and temporarily retains the urine. (6) In the device for measuring electrical characteristics of urine described in (5) above, the plurality of first electrodes are embedded in part or all of the outer periphery of the porous body, and the cylindrical body holds the porous body and fixes the plurality of first electrodes in a liquid-tight manner. (7) In the device for measuring electrical characteristics of urine described in any one of (2) to (6) above, the retention portion comprises a cylindrical body and a disk-shaped first restriction portion disposed within the cylindrical body and restricting urine permeation, and the plurality of first electrodes are disposed above the first restriction portion. (8) In the device for measuring electrical characteristics of urine described in (7) above, a flow path is formed in the first restriction portion, and the measurement portion measures the electrical characteristics of urine retained in the space above the first restriction portion. (9) In the device for measuring electrical characteristics of urine described in (7) or (8) above, the retention portion comprises a disk-shaped second restriction portion disposed opposite the first restriction portion with the plurality of first electrodes therebetween and restricting urine permeation. (10) In the device for measuring electrical characteristics of urine described in (9) above, a flow path is formed in a first peripheral portion of the first restricting portion, and a flow path is formed in a second peripheral portion of the second restricting portion that faces the first peripheral portion across the central axis of the cylindrical body. (11) In the device for measuring electrical characteristics of urine described in (9) or (10) above, the measuring portion measures the electrical characteristics of urine retained in the space between the first restricting portion and the second restricting portion.(12) The electrical characteristics measuring device for urine according to any one of (1) to (11) above comprises a detector that detects the number of drops of urine dispensed and a calculator that calculates the urine flow rate based on the number of drops detected by the detector. (13) A system for measuring electrical characteristics of urine according to the present disclosure comprises the aforementioned electrical characteristics measuring device for urine and a storage device that stores the electrical characteristics of urine measured by the electrical characteristics measuring device. (14) A system for measuring electrical characteristics of urine according to the present disclosure comprises the aforementioned electrical characteristics measuring device for urine and a display device that displays the electrical characteristics of urine measured by the electrical characteristics measuring device. (15) A system for measuring electrical characteristics of urine according to the present disclosure comprises the aforementioned electrical characteristics measuring device for urine and a converter that converts the electrical characteristics of urine measured by the electrical characteristics measuring device into at least one of urine osmolality, urinary sodium chloride concentration, and urinary sodium excretion rate. (16) A system for measuring electrical characteristics of urine according to the present disclosure comprises the aforementioned electrical characteristics measuring device for urine and a determination device that determines the effectiveness of a diuretic based on the electrical characteristics of urine measured by the electrical characteristics measuring device. (17) A system for measuring electrical characteristics of urine according to the present disclosure includes the aforementioned device for measuring electrical characteristics of urine and a measuring device for measuring a partial pressure of urine oxygen, the measuring device including a correction unit for correcting the measured partial pressure of urine oxygen based on the electrical characteristics of urine measured by the electrical characteristics measuring device. (18) A method for measuring electrical characteristics of urine according to the present disclosure includes a retaining unit temporarily retaining urine dripped from a dripping unit, and a measuring unit measuring the electrical characteristics of the retained urine.

[0008] According to the present disclosure, the electrical properties of urine can be measured continuously.

[0009] 1 is a diagram showing an example of the external appearance of a main part of a device for measuring electrical properties of urine according to the present embodiment; FIG. 2 is a diagram showing a first example of the configuration of a device for measuring electrical properties of urine; FIG. 3 is a diagram showing an example of the configuration of a measurement unit; FIG. 4 is a diagram showing a second example of the configuration of a device for measuring electrical properties of urine; FIG. 5 is a diagram showing a fifth example of the configuration of a device for measuring electrical properties of urine; FIG. 6 is a diagram showing an example of the configuration of a urinary drainage system according to the present embodiment; FIG. 7 is a diagram showing an example of the configuration of a system for measuring electrical properties of urine according to the present embodiment; FIG. 8 is a diagram showing a schematic diagram of the relationship between urinary conductivity and urinary osmotic pressure; FIG. 9 is a diagram showing an example of measurement results displayed on a display device; FIG. 10 is a diagram showing a schematic diagram of the relationship between urinary conductivity and urinary sodium chloride concentration; FIG. 11 is a diagram showing a formula for calculating urinary sodium excretion rate; FIG. 12 is a diagram showing an example of correction of urinary oxygen partial pressure; FIG. 13 is a diagram showing an example of measurement of the effect of a diuretic.

[0010] Embodiments of the present disclosure will now be described. Fig. 1 is a diagram showing an example of the external appearance of the main parts of an apparatus 100 for measuring electrical characteristics of urine according to this embodiment, and Fig. 2 is a diagram showing a first example of the configuration of the apparatus 100 for measuring electrical characteristics of urine. The apparatus 100 for measuring electrical characteristics of urine includes a dripping section 10, a retention section 20, a flow rate sensor section 40, and a measurement unit 50 as a measurement section. For convenience, Fig. 2 illustrates the internal structure of the retention section 20 so that it can be seen. This also applies to Figs. 4 to 7 described below.

[0011] Dripping unit 10 is a transparent cylindrical container body similar to a general drip tube. A cap 11 is provided on top of dripping unit 10. A tube (not shown) is connected to cap 11. Dripping unit 10 forms a drip port with a narrow diameter so that urine flowing from the tube drips as droplets D.

[0012] The flow rate sensor unit 40 includes a light-emitting unit 41 and a light-receiving unit 42, which are arranged opposite each other with the dripping unit 10 in between. The light-emitting unit 41 continuously irradiates the required light toward the light-receiving unit 42. The light-receiving unit 42 can receive the light emitted by the light-emitting unit 41. When urine drips from the dripping unit 10, the light emitted from the light-emitting unit 41 is blocked by the droplets D, and the light-receiving unit 42 cannot receive the light. The flow rate sensor unit 40 calculates the urine flow rate based on the light-receiving signal output by the light-receiving unit 42 in response to the received light. The urine flow rate can be calculated, for example, by {urine flow rate = number of drops per unit time x volume of one drop}.

[0013] That is, the urine electrical characteristic measuring device 100 includes a detector that detects the number of drops of urine that have been dropped, and a calculator that calculates the urine flow rate based on the number of drops detected by the detector.

[0014] The retention section 20 includes a cylindrical body 21 and a porous body 22 disposed within the cylindrical body 21 for temporarily retaining urine. The cylindrical body 21 is cylindrical and can accommodate the porous body 22 therein. The porous body 22 is cylindrical and can be made of, for example, a resin foam such as a sponge, and has excellent water absorption capabilities due to its hydrophilic water properties and fine, continuous porous structure. Droplets (urine) dripping from the drip section 10 are temporarily held in the porous body 22. When the amount of urine held in the porous body 22 exceeds a predetermined amount, the urine held in the porous body 22 flows into a conduit 60 connected to the lower side of the retention section 20.

[0015] The frame 30 is provided below the dripping section 10, and a protrusion that fits into a groove formed on the outer periphery of the retaining section 20 is formed on the inner wall of the frame 30. The frame 30 determines the mounting position of the retaining section 20 and can hold the retaining section 20. A rectangular locking section 31 is attached to the frame 30. The locking section 31 is provided so as to be rotatable around a shaft 32 on one side. By fitting the locking section 31 into the frame 30, the retaining section 20 can be fixed to the frame 30 and the retaining section 20 can be positioned below the dripping section 10.

[0016] With the above-described configuration, urine flowing in from the tube connected to the cap portion 11 drips drop by drop in the drip portion 10 and is temporarily held in the retention portion 20 (porous body 22), and when the amount of held urine exceeds a predetermined amount, it flows into the conduit 60. This makes it possible to realize a structure that allows fresh urine collected from the patient's body via the urinary catheter to flow continuously while retaining a constant amount (i.e., by slowing the flow rate).

[0017] A plurality of first electrodes 1 are embedded in part or all of the outer periphery of the porous body 22. The number of first electrodes 1 may be two, or may be three or more. The first electrodes 1 may be arranged, for example, at equal intervals along the outer periphery of the porous body 22. The cylindrical body 21 holds the porous body 22 and fixes the plurality of first electrodes 1 in a liquid-tight manner. The plurality of first electrodes 1 are configured to be in continuous contact with urine retained in the retention section 20 (porous body 22 in the example of FIG. 2). Here, "continuous contact" refers to a state of constant contact rather than discrete contact.

[0018] The device includes a plurality of second electrodes 2 that can contact the plurality of first electrodes 1 at positions corresponding to the plurality of first electrodes 1, respectively. By fitting the locking portion 31 into the frame 30, the plurality of second electrodes 2 come into contact with the plurality of first electrodes, respectively. The plurality of second electrodes 2 are fixed to the frame 30. The measurement unit 50 can measure the electrical characteristics of urine by passing a current through each of the second electrodes 2. That is, each of the plurality of second electrodes 2 is electrically connected to each of the plurality of first electrodes 1. The measurement unit 50 can measure the electrical characteristics of urine temporarily retained (held) in the retention portion 20 (porous body 22) by applying a DC or AC voltage to the second electrodes 2. The electrical characteristics of urine include urine conductivity or urine resistivity.

[0019] As described above, the urine electrical characteristic measuring device 100 of this embodiment includes a dripping unit 10 for dripping urine, a retention unit 20 for temporarily retaining the dripped urine, and a measurement unit (measurement unit) 50 for measuring the electrical characteristics of the urine retained in the retention unit 20. By temporarily retaining the dripped urine and measuring the electrical characteristics of the retained urine, the electrical characteristics of fresh urine collected from a patient's body via a urinary catheter can be continuously measured. Furthermore, the presence of an air layer in the dripping unit 10 reduces the risk of the voltage applied by the measurement unit 50 conducting electricity through the liquid to the living body. In the following, the electrical characteristic of urine will be described as urine conductivity. Here, "continuous measurement" includes not only literally continuous measurement but also repeated measurement at a predetermined sampling period.

[0020] 3 is a diagram showing an example of the configuration of the measurement unit 50. The measurement unit 50 includes a control unit 51 that controls the entire measurement unit 50, a measurement unit 52, a calculation unit 53, a display unit 54, a storage unit 55, and a communication unit 56.

[0021] The control unit 51 may be configured by incorporating a required number of CPUs (Central Processing Units), MPUs (Micro-Processing Units), etc. The control unit 51 may also be configured by combining DSPs (Digital Signal Processors), FPGAs (Field-Programmable Gate Arrays), etc. The control unit 51 can control the operation of the flow sensor unit 40 (such as the light-emitting unit 41 and the light-receiving unit 42).

[0022] The measuring unit 52 is equipped with a DC power supply unit or an AC power supply unit, and measures the conductivity of urine temporarily retained in the retention unit 20 by applying a DC or AC voltage to the multiple second electrodes 2.

[0023] The calculation unit 53 can perform required calculations based on the measured urine conductivity. For example, the calculation unit 53 calculates urine osmotic pressure and urine sodium chloride concentration from the urine conductivity. Details of the calculations performed by the calculation unit 53 will be described later.

[0024] The display unit 54 can be configured with a liquid crystal panel, an organic EL (Electro Luminescence) display, etc. Instead of the display unit 54, an external display device may be provided.

[0025] The storage unit 55 can be configured with a semiconductor memory or the like, and stores time-series data of urine conductivity measured by the measurement unit 52, required information, and the like.

[0026] The communication unit 56 includes a communication module and can transmit and receive information to and from external devices via a communication network such as an in-hospital network.

[0027] FIG. 4 shows a second example of the configuration of the urine electrical characteristics measuring device 100. This differs from the first example shown in FIG. 2 in that it includes a spring member 3. The spring member 3 is provided corresponding to each second electrode 2. One end of the spring member 3 is fixed to the frame 30, and the other end is fixed to the second electrode 2. The spring member 3 is a member for reinforcing the contact between the first electrode 1 and the second electrode 2. By fitting the locking portion 31 into the frame 30, the spring member 3 presses the second electrode 2, and the pressed second electrode 2 presses the first electrode 1, thereby ensuring contact between the first electrode 1 and the second electrode 2. The measurement unit 50 can measure the electrical characteristics of urine by passing electricity through each second electrode 2. That is, each of the multiple second electrodes 2 is electrically connected to each of the multiple first electrodes 1. Alternatively, the measurement unit 50 may measure the electrical characteristics of urine by passing electricity through each second electrode 2 via the spring member 3.

[0028] Figure 5 is a diagram showing a third example of the configuration of the urine electrical characteristic measuring device 100. The difference from the first example shown in Figure 2 is that instead of the porous body 22, two porous bodies 23 and 24 are arranged facing each other at a distance. As shown in Figure 5, a cylindrical porous body 23 is provided on the upper side of the interior of a cylindrical body 21, and a cylindrical porous body 24 is provided on the lower side of the interior of the cylindrical body 21 at a distance from the porous body 23. The porous bodies 23 and 24 can be formed of sponges, as in the first example.

[0029] As the pore diameter of the porous bodies 23, 24 becomes smaller, urine permeation becomes more difficult, and the porous bodies 23, 24 function as a restricting member that restricts urine permeation. In the example of FIG. 5 , the retention section 20 includes a cylindrical body 21 and a porous body 24 as a disk-shaped first restricting section disposed within the cylindrical body 21 and restricting urine permeation, with multiple first electrodes 1 disposed above the porous body 24 (first restricting section). The retention section 20 also includes a porous body 23 disposed opposite the porous body 24 with multiple first electrodes 1 interposed therebetween and serving as a disk-shaped second restricting section that restricts urine permeation. Dripped urine is temporarily retained in the porous body 23, and urine exceeding a certain amount accumulates in the space 25 between the porous bodies 23 and 24 and is temporarily retained in the porous body 24. When the amount of urine retained in the porous body 24 exceeds a certain amount, it flows from the porous body 24 to the pipe 60.

[0030] With the above-described configuration, measurement unit 50 can measure the conductivity of urine accumulated in space 25 between porous body 24 and porous body 23. Furthermore, because first electrode 1 is not embedded in a porous body such as a sponge, it is possible to eliminate the effects of changes in the amount of urine held due to factors such as the compressibility of the sponge, and pores (spaces) that occur around first electrode 1, thereby enabling more accurate measurement of urine conductivity.

[0031] FIG. 6 shows a fourth example of the configuration of the urine electrical characteristic measuring device 100. This example differs from the third example shown in FIG. 5 in that plates 26 and 27 are provided instead of the porous bodies 23 and 24. The plates 26 and 27 function as a second restricting portion and a first restricting portion, respectively, and may be formed of a urine-impermeable film or the like. As shown in FIG. 6, holes serving as the flow path 8 are formed in a first peripheral portion (the right peripheral portion in the example shown in FIG. 6) of the lower plate 27, and holes serving as the flow path 8 are formed in a second peripheral portion (the left peripheral portion in the example shown in FIG. 6) of the upper plate 26. The holes may be circular when viewed from above the plates 26 and 27 along the central axis of the cylindrical body 21. Alternatively, the plates 26 and 27 may be formed with elongated holes instead of holes. Here, elongated holes are holes that have an elongated shape when viewed from above the plates 26 and 27 along the central axis of the cylindrical body 21. This allows the space 25 between the plates 26 and 27 to serve as a urine flow path. The above is just one example, and the shape of the holes may be designed in any way to provide an optimal combination as long as the flow of urine is regulated and the electrodes come into contact with each other.

[0032] As described above, the flow path 8 is formed in the first peripheral portion of the plate 27 (first restriction portion), and the flow path 8 is formed in the second peripheral portion of the plate 26 (second restriction portion) that faces the first peripheral portion across the central axis of the cylindrical body 21. The measurement unit 50 can measure the electrical characteristics of urine retained in the space 25 between the plates 27 and 26. This ensures that the first electrode 1 comes into contact with urine temporarily retained in the space 25 between the plates 26 and 27.

[0033] Figure 7 shows a fifth example of the configuration of a urine electrical characteristic measuring device 100. The difference from the fourth example shown in Figure 6 is that there is no plate 26 (second restriction portion). As shown in Figure 7, in the fifth example, a flow path 8 is formed in a plate 27 (first restriction portion), and the measuring unit 50 can measure the electrical characteristics of urine retained in a space 25 above the plate 27. This ensures that the first electrode 1 comes into contact with urine temporarily retained in the space 25 above the plate 27.

[0034] FIG. 8 shows an example of the configuration of a urinary drainage system according to this embodiment. The urinary drainage system includes a urine electrical characteristic measuring device 100, a urinary catheter, and a urine bag. A urine bag is connected to the urine electrical characteristic measuring device 100 via a conduit 60. A urinary catheter is connected to a tube connected to the urine electrical characteristic measuring device. The tip of the urinary catheter is equipped with a fluorescent oxygen partial pressure sensor, a temperature sensor, and a balloon-shaped fixing part for fixing the tip of the urinary catheter to the bladder. With this configuration, urine from the patient's body can be extracted using the urinary catheter and drained into the urine bag, while simultaneously measuring the urinary oxygen partial pressure, temperature, and electrical characteristics of the urine.

[0035] As described above, the urine electrical characteristic measuring device 100 can measure the conductivity of urine temporarily retained in the retaining portion 20. The urine electrical characteristic measuring device 100 can calculate the urine osmotic pressure from the measured urine conductivity. Furthermore, the urine electrical characteristic measuring device 100 can calculate the urine flow rate.

[0036] The fluorescent oxygen partial pressure sensor is attached to the tip of a urinary catheter and has a measuring unit composed of a light-transmitting substrate and a fluorescent material coated over almost the entire surface of one side of the substrate. The light-emitting unit 131 irradiates the fluorescent material with excitation light. The fluorescent material absorbs the energy of the excitation light, becoming excited, and emits fluorescence when returning from the excited state to its original stable state (ground state). When oxygen is present in urine, the fluorescent properties (fluorescence intensity or phase) change due to quenching. This change in the fluorescent properties in response to oxygen concentration can be measured and converted into oxygen concentration or partial pressure.

[0037] The calculation unit 53 of the urine electrical characteristic measuring device 100 can calculate pO2 (oxygen partial pressure) based on the value measured by the fluorescent oxygen partial pressure sensor.

[0038] As described above, the urine electrical characteristic measuring device 100 can continuously measure the conductivity of a patient's urine collected through a urinary catheter and obtain time-series data of urine conductivity. Furthermore, the urine electrical characteristic measuring device 100 can calculate time-series data of urine osmotic pressure and urine flow rate from the measured urine conductivity.

[0039] 9 is a diagram showing an example of the configuration of a system for measuring electrical characteristics of urine according to this embodiment. The system for measuring electrical characteristics of urine includes a urine electrical characteristic measuring device 100 including a measurement unit 50, a management server 200, a data server 210, a display device 220, a conversion device 230, a measurement device 240, and a determination device 250, which are interconnected via an in-hospital network N.

[0040] The data server 210 functions as a storage device and stores the urine conductivity measured by the urine electrical characteristic measuring device 100. The urine conductivity can be stored as time-series data for each patient.

[0041] The display device 220 is a device used by medical professionals and displays the urine conductivity measured by the urine electrical characteristic measuring device 100. The urine conductivity can be displayed as time-series data for each patient. The urine electrical characteristic measuring system may include multiple display devices 200.

[0042] The conversion device 230 converts the urine conductivity measured by the urine electrical characteristic measuring device 100 into at least one of the urine osmotic pressure, the urine sodium chloride concentration, and the urine sodium excretion rate.

[0043] The determination device 250 determines the effect of the diuretic based on the conductivity of the urine measured by the urine electrical characteristic measuring device 100 .

[0044] The measuring device 240 calculates the urinary oxygen partial pressure based on the value measured by the urinary catheter. The measuring device 240 also includes a correction unit that corrects the calculated urinary oxygen partial pressure based on the urine conductivity measured by the urine electrical characteristic measuring device 100.

[0045] The management server 200 manages the operations and information exchange of the urine electrical characteristic measuring device 100, the data server 210, the display device 220, the conversion device 230, the measurement device 240, and the determination device 250. All or part of the functions of the conversion device 230, the measurement device 240, and the determination device 250 may be integrated into the calculation unit 53 in the measurement unit 50, and the functions of the data server 210 and the display device 220 may be integrated into the storage unit 55 and the display unit 54 in the measurement unit 50. Furthermore, all or part of the management server 200, the data server 210, the display device 220, the conversion device 230, the measurement device 240, and the determination device 250 may be integrated into a single device.

[0046] Figure 10 is a diagram showing the relationship between urinary conductivity and urinary osmolality. As shown in Figure 10, there is a correlation between urinary conductivity and urinary osmolality, and as the urinary osmolality increases, the urinary conductivity increases in proportion to the urinary osmolality. Hypoosmolar urine with low urinary osmolality and hyperosmolar urine with high urinary osmolality are seen in various diseases, and since there is a correlation between urinary osmolality and urinary conductivity, measuring a patient's urinary conductivity is one way to determine whether or not a disease is present.

[0047] FIG. 11 shows an example of measurement results displayed on the display device 220. The measurement results screen displays a patient ID field for selecting a patient. By selecting or entering a patient ID, measurement results for the patient's urine can be displayed. In the example of FIG. 11, the patient's urine conductivity and osmolality are displayed in real time as numerical values. Time-series data of urine conductivity and osmolality acquired over a predetermined period of time from the present can also be displayed. This allows the user to understand changes in urine conductivity and osmolality over time. Note that the data displayed on the measurement results screen is not limited to urine conductivity and osmolality. Time-series data such as urinary sodium chloride concentration, urinary sodium excretion rate, and urinary oxygen partial pressure may also be displayed, either alone or in combination.

[0048] Fig. 12 is a diagram showing a schematic diagram of the relationship between urinary conductivity and urinary sodium chloride concentration. Urine conductivity is proportional to the amount of electrolytes in an aqueous solution, and since the most abundant electrolyte in urine is sodium chloride, there is a correlation between urinary conductivity and urinary sodium chloride concentration as shown in Fig. 12. The urinary conductivity measured by the urine electrical characteristic measuring device 100 of this embodiment accurately reproduces the correlation shown in Fig. 12.

[0049] Figure 13 shows the formula for calculating urinary sodium excretion. Urinary sodium excretion (FENa) is the ratio of sodium clearance CNa (sodium excretion capacity) to creatinine clearance CCr (creatinine excretion capacity). Specifically, it is calculated by dividing the ratio of urinary sodium UNa to blood sodium SNa by the ratio of urinary creatinine UCr to blood creatinine SCr. A FENa of less than 1% suggests prerenal renal failure, while a FENa of more than 1% suggests renal renal failure. Thus, FENa can be used to differentiate between prerenal and renal acute kidney injury (AKI).

[0050] FIG. 14 is a diagram showing an example of correction of urinary oxygen partial pressure. The conversion device 230 converts the urinary conductivity measured by the urine electrical characteristic measuring device 100 into a chloride ion concentration (sodium chloride concentration). The measurement device 240 calculates the urinary oxygen partial pressure value from the value measured with the urinary catheter, and also acquires the chloride ion concentration from the conversion device 230. The measurement device 240 corrects the calculated oxygen partial pressure value by inputting the chloride ion concentration value into the correction formula stored in the correction unit. In the correction formula shown in FIG. 14, T represents temperature, and A to D and P to S are constants. A = -7.424, B = 4.417 × 10 3 , C=-2.927, D=4.238×10 -2 , P=-1.288×10 -1 , Q=5.344×10, R=-4.442×10 -2 , S=7.145×10 -4 [Cl - ] is the chloride ion concentration.

[0051] When the chloride ion concentration is high due to the salting-out effect, the solubility of oxygen decreases, so the calculated oxygen partial pressure is higher than the actual pressure, and therefore the oxygen partial pressure needs to be corrected.The above-mentioned configuration makes it possible to obtain an accurate oxygen partial pressure.

[0052] FIG. 15 shows an example of measuring the effect of a diuretic. The most commonly used diuretic (furosemide sodium) increases urinary osmolality and increases urine volume by suppressing the reabsorption of sodium chloride from primary urine. When diuretics increase diuresis, urinary sodium chloride increases. Therefore, by examining urinary sodium chloride, it is possible to determine whether an increase in urine volume after furosemide administration is due to the effects of furosemide administration. The urine electrical characteristic measuring device 100 of this embodiment can continuously measure urinary conductivity, making it possible to visualize whether an increase in urine volume after furosemide administration to a living body is due to the effects of furosemide.

[0053] Figure 15 shows the time course of urine conductivity, urine volume, and bladder temperature when a pig is administered a diuretic. It can be seen that urine conductivity and urine volume increase relative to baseline (before furosemide administration) within 1 to 2 minutes of furosemide administration. It can also be seen that the effect of furosemide fades after a certain period of time. The effectiveness of a diuretic can be assessed by setting a certain threshold, or by the rate of change from baseline (before furosemide administration).

[0054] In clinical practice, a test called a furosemide challenge is sometimes performed to confirm responsiveness to furosemide. In the furosemide challenge, a fixed amount of furosemide is administered, and the responsiveness is determined based on the amount of urine obtained after a fixed period of time (e.g., two hours). The urinary electrical characteristic measuring device 100 of this embodiment may be used to perform a furosemide challenge test. In this case, the display unit 54 of the measurement unit 50 may be configured to display a menu useful for performing the furosemide challenge test on the display device 220.

[0055] Furthermore, whether or not natriuresis is being performed is also useful for determining the prognosis of acute heart failure, and since this can be determined based on osmotic pressure (concentration), continuous measurement of urinary conductivity using the urinary electrical characteristic measuring device 100 of this embodiment is also useful for determining the prognosis of acute heart failure. Furthermore, the parameters that have been measurable up to this point can be combined to be useful for assessing the state of the kidneys from multiple perspectives.

[0056] REFERENCE SIGNS LIST 1 First electrode 2 Second electrode 3 Spring member 8 Flow path 10 Dropping section 20 Retention section 21 Cylindrical body 22, 23, 24 Porous body 25 Space 26, 27 Plate 30 Frame 31 Locking section 32 Shaft 40 Flow rate sensor section 41 Light emitting section 42 Light receiving section 50 Measuring unit 51 Control section 52 Measuring section 53 Calculation section 54 Display section 55 Storage section 56 Communication section 60 Pipe line 200 Management server 210 Data server 220 Display device 230 Conversion device 240 Measurement device 250 Determination device

Claims

1. A urine electrical property measuring device, comprising a dropping part for dropping urine, a retention part for temporarily retaining the dropped urine, and a measuring part for measuring the electrical properties of the urine retained in the retention part.

2. The urine electrical property measuring device according to claim 1, further comprising a plurality of first electrodes that are in continuous contact with the urine retained in the retention part.

3. The urine electrical property measuring device according to claim 2, further comprising a plurality of second electrodes that are in contact with each of the plurality of first electrodes, wherein the measuring part measures the electrical properties of the urine by energizing each of the second electrodes.

4. The urine electrical property measuring device according to claim 3, further comprising a spring member for reinforcing the contact between the first electrodes and the second electrodes.

5. The urine electrical property measuring device according to any one of claims 2 to 4, wherein the retention part comprises a cylindrical body and a porous body disposed within the cylindrical body for temporarily retaining urine.

6. The urine electrical property measuring device according to claim 5, wherein a part or all of each of the plurality of first electrodes is embedded and disposed on the outer peripheral portion of the porous body, and the cylindrical body holds the porous body and fixes the plurality of first electrodes in a liquid-tight manner.

7. The urine electrical property measuring device according to any one of claims 2 to 4, wherein the retention part comprises a cylindrical body and a disk-shaped first restricting part disposed within the cylindrical body for restricting the permeation of urine, and the plurality of first electrodes are disposed above the first restricting part.

8. The urine electrical property measuring device according to claim 7, wherein a flow path is formed in the first restricting part, and the measuring part measures the electrical properties of the urine retained in the space above the first restricting part.

9. The urine electrical property measuring device according to claim 7, wherein the retention part comprises a disk-shaped second restricting part that is disposed opposite to the first restricting part with the plurality of first electrodes therebetween for restricting the permeation of urine.

10. The urine electrical property measuring device according to claim 9, wherein a flow path is formed in a first peripheral portion of the first restricting part, and a flow path is formed in a second peripheral portion of the second restricting part that is disposed opposite to the first peripheral portion with the central axis of the cylindrical body therebetween.

11. The urine electrical property measuring device according to claim 9, wherein the measuring part measures the electrical properties of the urine retained in the space between the first restricting part and the second restricting part.

12. The urine electrical property measurement device according to any one of claims 1 to 4, comprising: a detection unit that detects the number of drops of the dropped urine; and a calculation unit that calculates the urine flow rate based on the number of drops detected by the detection unit.

13. The urine electrical property measurement system, comprising: the urine electrical property measurement device according to any one of claims 1 to 4; and a storage device that stores the urine electrical properties measured by the electrical property measurement device.

14. The urine electrical property measurement system, comprising: the urine electrical property measurement device according to any one of claims 1 to 4; and a display device that displays the urine electrical properties measured by the electrical property measurement device.

15. The urine electrical property measurement system, comprising: the urine electrical property measurement device according to any one of claims 1 to 4; and a conversion device that converts the urine electrical properties measured by the electrical property measurement device into at least one of urine osmotic pressure, sodium chloride concentration in urine, and sodium excretion rate in urine.

16. The urine electrical property measurement system, comprising: the urine electrical property measurement device according to any one of claims 1 to 4; and a determination device that determines the effect of a diuretic based on the urine electrical properties measured by the electrical property measurement device.

17. The urine electrical property measurement system, comprising: the urine electrical property measurement device according to any one of claims 1 to 4; and a measurement device that measures the partial pressure of uric acid, wherein the measurement device includes a correction unit that corrects the measured partial pressure of uric acid based on the urine electrical properties measured by the electrical property measurement device.

18. A method for measuring the electrical properties of urine, in which the urine dropped from the dropping part is temporarily retained by a retention part, and the measurement part measures the electrical properties of the retained urine.

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