Medical liquid detection devices and tagging devices

Abstract

To provide a medical liquid detection device with a new structure capable of more stably detecting liquid leakage.SOLUTION: A medical liquid detection device 10 for detecting medical detection object liquid 6 that has leaked from a liquid communication circuit 8 includes: an RF tag 18; tag holding means 16 for arranging the RF tag 18 under an arm part 5 of a patient 4 connected to the liquid communication circuit 8; a reader / writer device 14 for executing communication by a radio wave with the RF tag 18; and a detection part 34 for electrically detecting leakage of the medical detection object liquid 6 on the basis of a change in a state of the communication between the RF tag 18 and the reader / writer device 14.SELECTED DRAWING: Figure 1

Description

Technical Field

[0005] , , , ,

[0001] The present invention relates to a medical liquid detection device and a tagging device used for detecting blood leakage and the like in the medical field.< /

Background Art

[0002] In the medical field, in procedures that require treatment over a long period of time, liquid leakage may become a problem. Therefore, it may be necessary to detect early when leakage of a liquid such as blood occurs. For example, during dialysis, a liquid leakage (leakage of liquid) may occur where blood or a chemical solution leaks from the puncture site due to the needle coming out of the patient, etc., and it is necessary to detect the liquid leakage and take measures before it becomes a major problem. However, since it is not realistic for busy medical staff to continuously monitor from the start to the completion of the dialysis procedure, the adoption of a liquid detection device that automatically detects liquid leakage has been considered.< /

[0003] Conventionally, for example, as described in Japanese Unexamined Patent Application Publication No. 2012-196293 (Patent Document 1), the patient's forearm is placed on a sheet having a plurality of detection wirings, and when a liquid leakage such as blood contacts the detection wirings and is electrically short-circuited, a liquid leakage is detected based on a change in electrical resistance or the like. An electric resistance type liquid detection device has been proposed. Also, as described in Japanese Unexamined Patent Application Publication No. 2017-042302 (Patent Document 2), a camera type liquid detection device that optically monitors the detection target with a camera has also been proposed.< /

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, electrical resistance type liquid detection devices, such as those described in Patent Document 1, can detect even small amounts of liquid depending on their location and spread, which could lead to false detection of liquids that do not need to be detected, such as a patient's sweat. Furthermore, camera type liquid detection devices, such as those described in Patent Document 2, may fail to detect the target liquid if, for example, the puncture site where leakage is expected during sleep is covered by a blanket.

[0006] The problem to be solved by the present invention is to provide a medical liquid detection device with a novel structure that enables more stable detection of leaks. Furthermore, the present invention also aims to provide a tagging device that constitutes such a medical liquid detection device. [Means for solving the problem]

[0007] The following describes preferred embodiments for understanding the present invention. However, each embodiment described below is illustrative and can be combined with others as appropriate. Furthermore, the multiple components described in each embodiment can be recognized and adopted as independently as possible, and can be combined with any component described in another embodiment as appropriate. Thus, the present invention is not limited to the embodiments described below, and various other embodiments can be realized.

[0008] The first embodiment is a medical liquid detection device for detecting a medically detectable liquid leaking from a fluid passage circuit, comprising: an RF tag; a tag holding means for positioning the RF tag below the patient's arm connected to the fluid passage circuit; a reader / writer device for communicating with the RF tag by radio waves; and a detection unit for electrically detecting the leakage of the medically detectable liquid based on a change in the communication state between the RF tag and the reader / writer device. A spacer is provided to set the distance from the arm to the RF tag. It is.

[0009] According to the medical liquid detection device constructed in accordance with this embodiment, the medical liquid to be detected can be detected below the arm based on changes in the communication state between the RF tag and the reader / writer device, thus enabling more stable detection of leaks. In particular, even when the area where the medical liquid to be detected needs to be detected is covered and not visible, the presence or absence of the medical liquid can be determined. Furthermore, according to the medical liquid detection device with a structure conforming to this embodiment, a spacer is placed between the human body and the RF tag, thereby preventing false detections due to the influence of the human body when the medical liquid to be detected is not detected.

[0010] The second embodiment is a medical liquid detection device as described in the first embodiment, wherein the arm portion can be placed without being fixed to the tag holding means on which the RF tag is arranged.

[0011] According to the medical liquid detection device constructed in accordance with this embodiment, even if a patient changes their posture or moves their arm or changes the circumferential orientation of their arm, the tag holding means on which the RF tag is placed does not move in accordance with the arm. As a result, the RF tag and the reader / writer device are maintained in a facing state, and communication between the RF tag and the reader / writer device is maintained, thus enabling continuous liquid leakage detection.

[0012] A third embodiment is a medical liquid detection device as described in the first or second embodiment, wherein the tag holding means includes an absorbent that absorbs the medical liquid to be detected, and the absorbent is positioned in close proximity to the RF tag.

[0013] According to the medical liquid detection device constructed in accordance with this embodiment, the medical liquid to be detected is absorbed by the absorber and held near the RF tag. This efficiently induces a change in the communication state between the RF tag and the reader / writer device due to the presence of the medical liquid, thereby enabling more accurate detection of the medical liquid.

[0016] The 4 The aspects of this are: 1st to 2nd 3 A medical liquid detection device described in any one of the embodiments, wherein the liquid flow circuit is configured to include a blood circuit, and the medical liquid to be detected is blood.

[0017] A medical liquid detection device with a structure according to this embodiment can detect blood leakage in a blood circuit, for example, which includes a patient's vascular system and an external circuit such as a dialysis circuit connected to the blood vessels.

[0018] The 5 The manner of is, 4 In the medical liquid detection device described in the embodiment, the RF tag is placed on the underside of a flat sheet that is laid below the puncture portion into a blood vessel of the dialysis circuit constituting the blood circuit to block the passage of the medical liquid to be detected, and the reader / writer device is placed below the RF tag, with the RF tag and the reader / writer device facing each other in the vertical direction.

[0019] According to the medical liquid detection device constructed in accordance with this embodiment, in hemodialysis requiring puncture of blood vessels, blood leakage from the puncture site can be detected by detecting the blood accumulating on a sheet placed below the puncture site or being absorbed by the absorbent material of the sheet based on changes in the communication state between an RF tag and a reader / writer device. In particular, during long-duration hemodialysis, even if the puncture site is covered with a blanket or the like and becomes invisible, or if there is some movement of the puncture site, blood leakage can be reliably detected. [Effects of the Invention]

[0022] According to the present invention, more stable detection of leaks becomes possible in medical liquid detection devices. Furthermore, a tagging device that operates effectively in medical liquid detection devices achieving the above-mentioned effects can be provided. [Brief explanation of the drawing]

[0023] [Figure 1] A diagram showing an example of the use of a medical liquid detection device as a first embodiment of the present invention, illustrating a state in which blood is not detected. [Figure 2] Cross-sectional view showing the tag device that constitutes the liquid detection device in Figure 1. [Figure 3] Block diagram of the liquid detection device shown in FIG. 1 [Figure 4] A diagram showing an example of use of the liquid detection device of FIG. 1, showing a state in which blood is detected [Figure 5] Cross-sectional view showing a tag device constituting a medical liquid detection device as another embodiment of the present invention [Figure 6] Cross-sectional view showing a tag device constituting a medical liquid detection device as another embodiment of the present invention [Figure 7] Cross-sectional view showing a tag device constituting a medical liquid detection device as yet another embodiment of the present invention

Mode for Carrying Out the Invention

[0024] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0025] In FIG. 1, a medical liquid detection device 10 as a first embodiment of the present invention is shown. The liquid detection device 10 monitors, for example, leakage of blood 6 as a medical detection target liquid due to needle detachment or the like at the puncture site of the forearm 5 of the patient 4 at the blood collection port 2 and the blood return port 3 of the artificial dialysis device 1. In the following description, the vertical direction generally refers to the vertically upward and downward direction in the state of use of the liquid detection device 10.

[0026] The liquid detection device 10 includes a tag device 12 and a reader / writer device 14. As shown in FIG. 2, the tag device 12 has a structure in which an RF tag 18 is attached to the lower surface of a sheet 16 as tag holding means.

[0027] The sheet 16 is roughly flat and has a laminated structure in which an absorbent 20, an impermeable film 22, and a cushion 24 are overlapped and fixed to each other. The absorbent 20 is capable of absorbing and retaining the medically detectable liquid (blood 6). The material used to form the absorbent 20 is not particularly limited, but as it comes into contact with the forearm 5 of the patient 4 as described later, it is preferably formed from, for example, a laminated nonwoven fabric to ensure a good tactile feel and prevent sticking.

[0028] An impermeable film 22 is superimposed on the underside of the absorbent body 20. The impermeable film 22 is a thin-walled member that prevents the passage of blood 6, and is made of, for example, polyethylene terephthalate, and is flexible. The sheet 16 has the function of preventing the passage of blood 6 by being equipped with the impermeable film 22, and the blood 6 absorbed by the absorbent body 20 is held on the impermeable film 22.

[0029] Furthermore, a cushioning body 24 is superimposed on the underside of the impermeable film 22. The cushioning body 24 is formed from, for example, laminated nonwoven fabric, and in this embodiment, it is made of the same material as the absorbent body 20.

[0030] Sheet 16 functions as a spacer to set the separation distance between the RF tag 18 and the forearm 5. In sheet 16, the thickness of the absorbent 20 is limited by its blood absorption performance, etc., and the thickness of the impermeable film 22 is limited by its flexibility, cost, etc. Therefore, the thickness of sheet 16 is mainly adjusted by the cushion body 24, and the separation distance between the RF tag 18 and the forearm 5 is set by adjusting the thickness of the cushion body 24. In other words, the thickness and number of layers of the nonwoven fabric constituting the cushion body 24 are set according to the required separation distance between the RF tag 18 and the forearm 5. However, the absorbent 20 is positioned close to the RF tag 18, and the thickness dimensions of the impermeable film 22 and the cushion body 24 are made small enough that when the blood 6 absorbed by the absorbent 20 reaches the impermeable film 22, the radio communication state of the RF tag 18 is affected by the blood 6.

[0031] The RF tag 18 is a thin sheet and, as shown in Figure 3, is equipped with a tag-side antenna 26 and a tag-side control chip 28. The RF tag 18's operation control of the tag-side antenna 26, processing of received signals, and generation of transmitted signals (response signals) are performed by the tag-side control chip 28. The RF tag 18 is preferably a passive tag that operates using radio waves from the reader / writer device 14, which will be described later, but it may also be an active tag with a built-in power supply, or a semi-passive tag that is activated by radio waves from the reader / writer device 14 and operates using a built-in power supply.

[0032] The RF tag 18 preferably includes a protective body (not shown) that protects the inlet consisting of a tag-side antenna 26 and a tag-side control chip 28. The protective body covers the surface of the inlet to prevent failure of the tag-side antenna 26 and tag-side control chip 28 due to direct contact with liquids, etc., and is formed of, for example, resin.

[0033] The RF tag 18 is positioned within the area where the leaked blood 6 is absorbed and held by the absorbent 20. That is, in this embodiment, the blood 6 flowing from the forearm 5 placed on the sheet 16 flows down to the absorbent 20 of the sheet 16, then flows downward within the absorbent 20 to the impermeable film 22. Since the forearm 5 is placed on the sheet 16 such that the blood collection port 2 and blood return port 3 from which the blood 6 leaks are located in the central part of the sheet 16, the blood 6 tends to flow downward through the central part of the sheet 16 and is mainly held by the absorbent 20 in the central part. Therefore, in this embodiment, the RF tag 18 is attached to the underside of the central part of the sheet 16.

[0034] The reader / writer device 14 is a device that communicates with the RF tag 18 using radio waves, and the reader / writer device 14 and the RF tag 18 constitute RFID (Radio Frequency Identification). The reader / writer device 14 includes an RW-side antenna 32 for sending and receiving signals with the RF tag 18, and an RW-side control unit 34 that controls the operation of the RW-side antenna 32, generates transmission signals, and processes received signals (response signals). The reader / writer device 14 transmits radio waves of transmission signals to the RF tag 18 at predetermined time intervals. The reader / writer device 14 is located separately below the tag device 12, preferably positioned vertically opposite and below the tag device 12. The reader / writer device 14 may be portable, or it may be fixedly installed, for example, in a building, other medical equipment, a bed 7, etc.

[0035] The RF tag 18 and the reader / writer device 14 communicate with each other using radio waves in the UHF (Ultra Hi Frequency) band of approximately 920 MHz. Specifically, when a UHF band radio wave transmitted from the RW-side antenna 32 of the reader / writer device 14 is received by the tag-side antenna 26 of the RF tag 18, the tag-side control chip 28 of the RF tag 18 operates using the received radio wave as power and generates a response signal. The response signal transmitted from the tag-side antenna 26 is received by the RW-side antenna 32 of the reader / writer device 14. The RF tag 18 may respond immediately upon receiving radio waves transmitted from the reader / writer device 14, or it may respond only when it receives a response command signal from the reader / writer device 14.

[0036] The liquid detection device 10, with the structure described above, detects, for example, leakage of blood 6 in the blood circuit 8, which is a fluid passage circuit formed by the hemodialysis machine 1 and the blood vessels of the patient 4. More specifically, as shown in Figure 1, the liquid detection device 10 is used to detect leakage of blood 6 at the puncture points (blood collection port 2 and blood return port 3) into the blood vessels of the patient 4 in the hemodialysis machine 1. In Figure 1, the patient 4 is lying face up on the bed 7, and the blood collection port 2 and blood return port 3, which are the patient 4 end of the dialysis circuit of the hemodialysis machine 1, are punctured into the forearm 5 of the patient 4. As a result, the dialysis circuit that constitutes the blood circuit 8 is connected to the forearm 5. In addition, a tag device 12 is laid on the top surface of the bed 7, and the puncture points of the blood collection port 2 and blood return port 3 on the forearm 5 of the patient 4 are placed on the tag device 12. The forearm 5 is designed to be placed on the tag device 12 without being fixed in place, and the RF tag 18 is positioned below the forearm 5 when the forearm 5 is placed on the tag device 12. The forearm 5 is superimposed on the absorbent material 20 that makes up the upper part of the sheet 16, in contact with it. On the other hand, the reader / writer device 14 is installed on the floor below the bed 7 and is positioned opposite the RF tag 18 of the tag device 12 in the vertical direction.

[0037] Then, the reader / writer device 14 transmits radio waves in the UHF band to the RF tag 18, and the liquid detection device 10 detects blood leakage 6 based on whether or not the RF tag 18 responds to the radio waves.

[0038] In other words, as shown in Figure 1, if there is no blood 6 leakage, the radio waves transmitted from the reader / writer device 14 are received by the RF tag 18, causing the RF tag 18 to send a response signal to the reader / writer device 14, which then receives the response signal. This response from the RF tag 18 indicates to the reader / writer device 14, acting as the detection unit, that the medical detection target liquid (blood 6) is not present in close proximity to the RF tag 18.

[0039] On the other hand, as shown in Figure 4, if there is leakage of blood 6 from the puncture site, the radio waves transmitted from the reader / writer device 14 are absorbed by the blood 6 held near the RF tag 18 by the absorber 20, and the radio waves supplied to the RF tag 18 become weaker. As a result, the response signal from the RF tag 18 becomes weaker or disappears, and the communication state changes compared to when there is no leakage of blood 6. The RW-side control unit 34 of the reader / writer device 14 then detects that there is blood 6 near the RF tag 18 based on the change in the communication state, which is that there is no valid response from the RF tag 18.

[0040] The detection unit that electrically detects the leakage of blood 6 may be configured by the RW-side control unit 34 of the reader / writer device 14, as in this embodiment, but it may also be configured by another device connected to the reader / writer device 14. For example, if there is no valid response from the RF tag 18, the reader / writer device 14 may generate a liquid detection signal and transmit the liquid detection signal to a processing device (such as a personal computer) not shown, which is connected to the reader / writer device 14 by wire or wireless. In this case, the processing device that receives the liquid detection signal performs the blood detection process.

[0041] Thus, the liquid detection device 10 can detect blood leakage 6 due to unintended needle dislodgement at the blood collection port 2 and the blood return port 3, based on changes in the communication state between the RF tag 18 and the reader / writer device 14. In particular, by detecting blood 6 based on changes in the communication state via radio waves, it is possible to effectively detect blood leakage 6 even if, for example, the blood collection port 2 and the blood return port 3 on the forearm 5 are covered with a blanket or the like and are not visible from the outside.

[0042] In this embodiment, the RF tag 18 is attached to the underside of the sheet 16, and the forearm 5 is placed on the sheet 16. As a result, even if the forearm 5 moves horizontally or rotates circumferentially on the sheet 16, the sheet 16, which is not fixed to the forearm 5, does not move in accordance with the forearm 5, and the RF tag 18 attached to the sheet 16 is held in a position facing the reader / writer device 14 in the vertical direction. Therefore, even if the patient 4 moves the forearm 5 on the sheet 16, it is less likely to affect the communication state between the RF tag 18 and the reader / writer device 14, and effective detection of blood leakage 6 can be maintained.

[0043] In this embodiment, an impermeable film 22 is placed below the absorbent material 20 to prevent the passage of blood 6. As a result, the blood 6 that passes through the absorbent material 20 remains on the impermeable film 22 without reaching the bed 7. This keeps the blood 6 absorbed by the absorbent material 20 and prevents the bed 7 from becoming soiled by the blood 6.

[0044] Furthermore, a cushioning body 24 is placed between the impermeable film 22 and the RF tag 18, and a spacer that adjusts the distance between the forearm 5 and the RF tag 18 is composed of the impermeable film 22 and the cushioning body 24. By providing such a spacer, it is possible to prevent the radio waves emitted from the reader / writer device 14 from being excessively absorbed by the forearm 5, and radio waves can be effectively supplied to the RF tag 18 when there is no blood leakage 6.

[0045] Furthermore, the absorbent material 20 that has not absorbed the blood 6 also acts as a spacer to separate the forearm 5 from the RF tag 18. However, if the absorbent material 20 is excessively thick, when blood 6 leaks, more of the blood 6 will be absorbed by the absorbent material 20 along the path to the impermeable film 22, requiring more bleeding to reach the vicinity of the impermeable film 22, which is close to the RF tag 18, in order to reach a detectable amount of blood 6. Also, if the impermeable film 22 is made thicker, problems such as the flexibility of the sheet 16 are impaired will occur. Therefore, in this embodiment, by providing a cushion body 24 between the impermeable film 22 and the RF tag 18, it is possible to ensure the flexibility of the sheet 16 on which the forearm 5 rests while accurately detecting blood 6 with an appropriate amount of bleeding.

[0046] The tagging device 12 of the liquid detection device 10 can be reused multiple times by performing treatments such as cleaning and sterilization after use, but it is preferably used only once. This allows the tagging device 12, which has an absorbent material 20 that comes into contact with the patient 4, to be kept clean, and infection between patients 4 can be prevented.

[0047] In the liquid detection device 10 of this embodiment, when a blood leak 6 is detected, the detection of blood 6 is notified to the outside by the notification device 36. The notification device 36 is composed of, for example, a light 38 and a speaker 40, and the presence or absence of illumination of the light 38 and sound output of the speaker 40, as well as the manner of illumination and sound output (e.g., illumination and sound output pattern, illumination color, pitch), etc., are controlled by the RW side control unit 34. In addition, doctors, family members, etc., can also be notified by making the light 38 or speaker 40, which are located away from the tag device 12 and reader / writer device 14, illuminate or emit sound via wireless communication such as Bluetooth®. For example, the notification device 36 may be an existing notification device such as a light 38 and speaker 40 installed in a nurse's waiting room or a smartphone, or a light 38 and speaker 40 may be installed near the entrance of the patient's room to notify the outside of an abnormality.

[0048] In the liquid detection device 10 of this embodiment illustrated in Figure 1, the reader / writer device 14 and the notification device 36 are separated from each other, and the reader / writer device 14 and the notification device 36 are interconnected by wire or wireless. The notification device 36 is set at a lower position on the hemodialysis machine 1 so that its light emission is easily visible and that it is easy to stop the light emission and sound emission.

[0049] Although embodiments of the present invention have been described in detail above, the present invention is not limited by its specific description. For example, the RF tags 18 can be held in a state overlapping with the forearm 5 by wrapping and fixing a sheet-like (strip-like) tag holding means to which the RF tags 18 are attached around the forearm 5 of the patient 4. In this case, for example, if a plurality of RF tags 18 are arranged with respect to the tag holding means at a distance from each other in the circumferential direction of the forearm 5, and one of the RF tags 18 is located below the forearm 5, a state in which leakage detection is possible can be maintained.

[0050] Although an example of a liquid detection device 10 equipped with one RF tag 18 and one reader / writer device 14 has been given, it is also possible to detect medically detectable liquids at multiple locations based on changes in the communication state between multiple RF tags 18 and one reader / writer device 14. In this case, by writing a code that allows for mutual identification of multiple RF tags 18, the reader / writer device 14 can identify the RF tags 18.

[0051] In the above embodiment, an RF tag 18 was illustrated in which the inlet is covered with a protective body to provide resistance to contact with the medical detection target liquid. However, for example, an RF tag that decomposes upon contact with the medical detection target liquid may also be used. In this case, if the medical detection target liquid leaks, the RF tag that has come into contact with the medical detection target liquid will decompose, thereby more reliably stopping the response function of the RF tag, and thus enabling accurate detection of the liquid leak. In this case, the absorbent 20 is not essential, and the leaked medical detection target liquid may come into contact with the RF tag without being collected and held in the absorbent 20.

[0052] In the above embodiment, an example was shown in which blood leakage 6 is detected when there is no response from the RF tag 18. However, depending on the amount of blood 6 leaking out and the distance between the blood 6 held by the absorber 20 and the RF tag 18, it is conceivable that there may be a response from the RF tag 18 even when blood 6 is leaking out. Therefore, blood leakage 6 is not necessarily limited to being detected by the disappearance of a response from the RF tag 18. For example, it may be detected when the intensity of the response signal from the RF tag 18 falls below a preset threshold. In short, leakage of the medical detection target liquid should be detected based on a change in the communication state between the reader / writer device 14 and the RF tag 18. This change in the communication state includes not only a complete interruption of communication, but also changes while communication is maintained, such as a decrease in communication signal strength or an increase in noise.

[0053] The structure of the sheet 16 is not limited to the three-layer structure shown in the above embodiment. For example, as shown in the tag devices 50, 60, and 70 in Figures 5 to 7, a sheet 52 can be used as a tag holding means consisting only of an absorber 20 and an impermeable film 22, with the cushion body (24) omitted. In the tag device 50 of Figure 5, the RF tag 18 is fixed to the upper surface of the impermeable film 22, and the RF tag 18 is positioned in direct contact with the absorber 20. In the tag device 60 of Figure 6, the RF tag 18 is embedded in the impermeable film 22, and the RF tag 18 may be exposed from the impermeable film 22 and in direct contact with the absorber 20, or it may be covered by the impermeable film 22. In the tag device 70 of Figure 7, the RF tag 18 is fixed to the lower surface of the impermeable film 22, and the impermeable film 22 is interposed between the RF tag 18 and the absorber 20. In all embodiments shown in Figures 5 to 7, the RF tag 18 and the absorber 20 are positioned in close proximity to each other, and there is no cushioning body (24) between the RF tag 18 and the absorber 20. In particular, in the tag devices 50 and 60 of Figures 5 and 6, the RF tag 18 can be positioned adjacent to the absorber 20. With the tag devices 50, 60 and 70 of Figures 5 to 7, which do not have such cushioning bodies (24), the medical detection target liquid (blood 6) absorbed by the absorber 20 is held closer to the RF tag 18, making the medical detection target liquid more susceptible to the influence of communication between the RF tag 18 and the reader / writer device 14, thereby improving the accuracy of leak detection. The spacer used to set the distance from the arm (forearm 5) to the RF tag 18 is composed of an absorbent 20 that does not absorb the medical detection target liquid in the tag devices 50 and 60 shown in Figures 5 and 6, and is composed of an absorbent 20 that does not absorb the medical detection target liquid and an impermeable film 22 in the tag device 70 shown in Figure 7.

[0054] In the above embodiment, a spacer for adjusting the distance between the forearm 5 and the RF tag 18 was made of a sheet 16. However, if, for example, the target liquid to be detected, such as blood, can be brought into direct contact with the RF tag 18, the impermeable film 22 can be omitted or placed below the RF tag 18 (on the opposite side from the forearm 5). Furthermore, in order to mitigate the decrease in detection accuracy due to the presence of a human body (forearm 5) with a high water content, a spacer with lower liquid retention and higher liquid permeability than the absorber 20, such as a hydrophilic porous material with continuous pores, can be placed between the human body (forearm 5) and the absorber 20 to ensure a large separation distance between the leaked liquid portion retained by the absorber 20 and the human body (forearm 5). In addition, since liquid retention is not required for the cushion body 24 between the impermeable film 22 and the RF tag 18, the material is arbitrary, and an appropriate thickness and characteristics can be set so that the absorber 20, which is the target liquid to be detected, and the RF tag 18 can be stably held at a separation distance advantageous for detection.

[0055] In the above embodiment, a flexible sheet 16 was exemplified, but for example, a sheet that maintains its shape in a flat form can be made by replacing the flexible opaque film 22 with a flat opaque plate. With such a flat sheet, movement of the RF tag 18 due to deformation of the sheet is prevented, and the RF tag 18 is held more stably in a facing position toward the reader / writer device 14. In addition, some deformation may be permitted even in a flat sheet; for example, deformation of the sheet may be permitted as long as the movement of the RF tag 18 due to the deformation of the sheet does not interfere with communication with the reader / writer device 14.

[0056] Furthermore, multiple RF tags 18 may be attached to a single sheet 16. This allows for expanding the area on the sheet 16 in which liquid can be detected, improving detection accuracy by considering the detection results from multiple RF tags through relative comparison or addition, and using another RF tag for support in case of a malfunction in an RF tag.

[0057] In the above embodiment, the example given was the detection of blood leakage 6 during hemodialysis. However, for example, in intravenous fluid administration, if the needle of the infusion circuit comes out of the patient's forearm 5, etc., and the drug solution leaks out, the drug solution can also be detected as a medical detection target liquid. Preferably, the medical detection target liquid is bodily fluid present in the human body, or a liquid such as a drug solution or blood transfusion supplied to the human body from an external source. Furthermore, the present invention originally includes all of the inventions described in (i) to (vii) below, and its structure and effects are noted below. The present invention (i) A medical liquid detection device for detecting a medically detectable liquid leaking from a fluid circuit, comprising: an RF tag; a tag holding means for positioning the RF tag below the patient's arm connected to the fluid circuit; a reader / writer device for communicating with the RF tag by radio waves; and a detection unit for electrically detecting the leakage of the medically detectable liquid based on a change in the communication state between the RF tag and the reader / writer device. (ii) The medical liquid detection device according to (i), wherein the arm portion can be placed in an unfixed manner on the tag holding means on which the RF tag is arranged. (iii) The medical liquid detection device according to (i) or (ii), wherein the tag holding means comprises an absorbent that absorbs the medical liquid to be detected, and the absorbent is positioned in close proximity to the RF tag. (iv) A medical liquid detection device according to any one of (i) to (iii) provided with a spacer for setting the distance from the arm to the RF tag, (v) A medical liquid detection device according to any one of (i) to (iv), wherein the fluid passage circuit is configured to include a blood circuit and the medically detectable liquid is blood. (vi) The medical liquid detection device according to (v), wherein the RF tag is placed on the underside of a flat sheet that is laid below the puncture portion into a blood vessel of the dialysis circuit constituting the blood circuit to block the passage of the medical liquid to be detected, and the reader / writer device is placed below the RF tag, and the RF tag and the reader / writer device are positioned facing each other in the vertical direction, (vii) A tag device comprising a medical liquid detection device for detecting a medically detectable liquid leaking from a fluid passage circuit, the tag device comprising an RF tag and a tag holding means for positioning the RF tag below the arm of a patient connected to the fluid passage circuit. This includes inventions relating to the present invention. In the invention described in (i) above, since the medical detection target liquid can be detected below the arm based on changes in the communication state between the RF tag and the reader / writer device, more stable detection of leaks becomes possible. In particular, even when the area where the medical detection target liquid needs to be detected is covered and not visible, the presence or absence of the medical detection target liquid can be determined. In the invention described in (ii) above, even if the patient moves their arm or changes its circumferential orientation, for example, by changing their posture, the tag holding means on which the RF tag is placed does not move in accordance with the arm. As a result, the RF tag and the reader / writer device are maintained in a facing state, and communication between the RF tag and the reader / writer device is maintained, thus allowing leakage detection to continue. In the invention described in (iii) above, since the medical detection target liquid is absorbed by the absorber and held near the RF tag, a change in the communication state between the RF tag and the reader / writer device due to the presence of the medical detection target liquid is efficiently induced, and the medical detection target liquid can be detected more accurately. In the invention described in (iv) above, a spacer is placed between the human body and the RF tag, thereby preventing false detections due to the influence of the human body when the medical detection target liquid is not detected. In the invention described in (v) above, for example, blood leakage can be detected in a blood circuit that includes the patient's vascular system and an external circuit such as a dialysis circuit connected to the blood vessels. In the invention described in (vi) above, in hemodialysis requiring puncture of a blood vessel, blood leakage from the puncture site can be detected by detecting the blood that accumulates on a sheet placed below the puncture site or is absorbed by the absorbent material of the sheet based on changes in the communication state between the RF tag and the reader / writer device. In particular, during long-duration hemodialysis, even if the puncture site is covered with a blanket or the like and becomes invisible, or if there is some movement of the puncture site, blood leakage can be reliably detected. In the invention described in (vii) above, by positioning the RF tag below the arm using a tag holding means, the leaked medical detection target liquid can be positioned near the RF tag, thereby effectively influencing the communication state of the RF tag. In the tag device according to this embodiment, for example, the absorbent described in (iii), the spacer described in (iv), the liquid impermeable sheet described in (vi), etc., can be appropriately combined and used. [Explanation of Symbols]

[0058] 10. Medical liquid detection device (first embodiment) 12 Tag device 14 Reader / Writer Device 16 sheets (tag holding means, spacers) 18 RF tags 20 absorbent material 22 Opaque Film 24 cushion body 26 Tag-side antenna 28 Tag-side control chip 32 RW side antenna 34 RW side control unit (detection unit) 36. Notification device 38 Light 40 Speakers 50 Tag device (another embodiment) 52 sheets (tag holding means) 60 Tag device (another embodiment) 70. Tag device (another embodiment) 1 Artificial dialysis machine 2. Blood collection point 3 Blood return port 4 patients 5. Forearm (arm) 6. Blood (Medical detection target liquid) 7 beds 8 Blood circuit (fluid circuit)

Claims

1. A medical liquid detection device that detects a medically detectable liquid leaking from a fluid passage circuit, RF tags and A tag holding means for positioning the RF tag below the patient's arm, which is connected to the fluid flow circuit, A reader / writer device that communicates with the RF tag via radio waves, A detection unit that electrically detects the leakage of the medically detected liquid based on a change in the communication state between the RF tag and the reader / writer device. It has, A medical liquid detection device provided with a spacer for setting the distance from the arm to the RF tag.

2. The medical liquid detection device according to claim 1, wherein the arm portion can be placed in an unfixed manner on the tag holding means on which the RF tag is arranged.

3. The medical liquid detection device according to claim 1 or 2, wherein the tag holding means comprises an absorbent that absorbs the medically detectable liquid, and the absorbent is arranged in close proximity to the RF tag.

4. The medical liquid detection device according to claim 1 or 2, wherein the fluid passage circuit is configured to include a blood circuit, and the medically detectable liquid is blood.

5. The medical liquid detection device according to claim 4, wherein the RF tag is placed on the underside of a flat sheet that is laid below the puncture portion into a blood vessel of the dialysis circuit constituting the blood circuit to block the passage of the medical detection target liquid, and the reader / writer device is placed below the RF tag, and the RF tag and the reader / writer device are positioned facing each other in the vertical direction.

Images