Operation method of perfusion state detection device, perfusion state detection device, and endoscope system

Abstract

This medical device: drives a pump for causing a liquid to flow in a pipe conduit that is inserted in a living body; measures the flow rate of the liquid flowing through the pipe conduit; detects a perfusion condition in the pipe conduit on the basis of the relationship between any two selected from among drive output to the pump, flow rate of the liquid flowing through the pipe conduit, and suction pressure in the pipe conduit; and controls the flow of the liquid in the pipe conduit on the basis of the result of detecting the perfusion condition.

Description

Technical Field

[0001] The present invention relates to a perfusion state detection method, a perfusion state detection device, and an endoscope system that can be used as a device for collecting stones in a subject. Operation of the device

Background Art

[0002] Conventionally, as a device for collecting stones from the body, a stone collection device has been developed that uses laser light to crush stones and collect the crushed stone pieces. For example, a technique has been proposed in which laser light is irradiated from a laser probe inserted into the treatment tool channel of an endoscope to finely crush stones. In this proposal, the crushed stones are grasped by forceps and removed outside the body.

[0003] There is also a stone treatment system that performs water supply and suction to collect stones. In this system, the stones are perfused with water through a suction tube and collected outside the body. However, the stones may get caught in the suction tube. Then, starting from the caught stone, subsequent stones may get caught, and ultimately, the suction tube may become blocked.

[0004] Therefore, Japanese Patent Application Laid-Open No. 2018-166725 discloses a technique for estimating the presence or absence of blockage in a suction line by monitoring the time change of the suction pressure in the suction line.

[0005] However, in the technique of Japanese Patent Application Laid-Open No. 2018-166725, there is a relatively large time difference between the occurrence of blockage in the suction line and the determination of the presence or absence of blockage.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] An object of the present invention is to provide a perfusion state detection method, a perfusion state detection device, and a medical device that can prevent a suction tube from becoming blocked.

Disclosure of the Invention

Means for Solving the Problems

[0008] The perfusion state detection Operation of the device method according to one aspect of the present invention is A method for operating a perfusion state detection device comprising a water supply pump that supplies a liquid via a water supply pipeline inserted into a living body, a suction pump that discharges the liquid via a suction pipeline inserted into the living body, and a processor, wherein the processor to drive a water supply pump Steps to perform and The to drive a suction pump Steps to perform , and in a plane showing the relationship between any two values of the drive output for the suction pump, the flow rate of the liquid flowing through the Suction pipe and the pressure in the Suction pipe, determine the distance between the coordinates on the plane based on the two values in the normal perfusion state of the Suction pipe and the coordinates on the actually measured plane Steps to perform , and detect an abnormality in the perfusion state of the Suction pipe according to whether the distance exceeds a threshold value, and based on the detection result of the perfusion state, control the flow of the liquid in the Suction pipe Having steps .

[0009] The perfusion state detection device according to one aspect of the present invention includes a water supply pipe inserted into a living body for supplying water to the living body, a water supply pump for supplying the liquid to the water supply pipe, a suction pipe inserted into the living body for sucking the liquid from the living body, a suction pump for discharging the liquid from the living body through the suction pipe, a valve for generating a reverse injection due to a water hammer action in the suction pipe, and a processor. The processor is in a plane showing the relationship between any two values of the drive output for the suction pump, the flow rate of the liquid flowing through the suction pipe, and the suction pressure in the suction pipe. SuctionObtain the distance between the coordinates on the plane based on the two values in the normal perfusion state of the pipeline and the actually measured coordinates on the plane, and detect the abnormality of the perfusion state of the suction pipeline according to whether the distance exceeds a first threshold value. Based on the detection result of the perfusion state, control the opening and closing of the valve to cause the reverse injection in the suction pipeline.

[0011] An endoscope system according to an aspect of the present invention includes an endoscope, a water supply pump that flows a liquid through a water supply pipeline of the endoscope, a suction pump that flows the liquid through a suction pipeline of the endoscope, a flow meter provided in the suction pipeline for measuring the flow rate of the liquid flowing through the suction pipeline, a valve for generating a reverse injection due to a water hammer action in the suction pipeline, and a processor. The processor is in a plane showing the relationship of any two values among the drive output for the suction pump, the flow rate of the liquid flowing through the suction pipeline, and the suction pressure in the suction pipeline. The Suction Obtain the distance between the coordinates on the plane based on the two values in the normal perfusion state of the pipeline and the actually measured coordinates on the plane, and detect the abnormality of the perfusion state of the suction pipeline according to whether the distance exceeds a first threshold value. Based on the detection result of the perfusion state, control the opening and closing of the valve to cause the reverse injection in the suction pipeline.

Effect of the Invention

[0012] According to the present invention, there is an effect that it is possible to prevent the suction tube from becoming blocked.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

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Figure 10

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Figure 17

Mode for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0015] (First Embodiment) FIG. 1 is a schematic configuration diagram showing a medical system including a medical device according to a first embodiment of the present invention. FIG. 2 is a block diagram showing the configuration of a medical device including a perfusion state detection device. In this embodiment, by detecting the state of perfusion based on the relationship between the flow rate flowing through the suction pipeline for discharging the calculus outside the body and the pump drive output, it is possible to detect early that the calculus has become caught.

[0016] With reference to FIG. 1, the medical system 1 including the medical device 10 will be described.

[0017] As shown in FIG. 1, the medical system 1 includes a medical device 10, an endoscope 20, a laser device 30, a video processor 40, a light source device 45, and a monitor 50. The endoscope 20 has an elongated insertion portion 21 and an operation portion 22. The endoscope 20 has the insertion portion 21 inserted into an organ of a subject, for example, a kidney, and images the organ to output an imaging signal.

[0018] The insertion portion 21 is configured such that, for example, a flexible portion 21a is formed on the proximal end side, a bending portion (not shown) is provided on the distal end side of the flexible portion 21a, and a rigid distal end portion 26 (see FIG. 3) is continuously provided on the distal end side of the bending portion. On the proximal end side of the insertion portion 21, an operation portion 22 provided with various buttons for operating the endoscope 20 is disposed. Note that the bending portion is configured to bend by operating the operation portion 22.

[0019] One end of a universal cord 23 is connected to the operation portion 22, and the other end of the universal cord 23 is connected to the video processor 40 and the light source device 45. The universal cord 23 interconnects the endoscope 20, the video processor 40, and the light source device 45, and transmits various signals and illumination light.

[0020] The video processor 40 controls the entire medical system 1. The video processor 40 receives an imaging signal from the endoscope 20 via the universal code 23, and obtains an image signal by performing signal processing on the input imaging signal. The video processor 40 outputs the image signal to the monitor 50. The monitor 50 displays an image based on the image signal output by the processor 40.

[0021] The light source device 45 has, for example, white LEDs and emits illumination light. The illumination light emitted by the light source device 45 is guided to the rigid distal end portion 26 via the universal code 23 and a light guide (not shown) inserted into the insertion portion 21.

[0022] The operation unit 22 is provided with a water supply tube mounting base 24 and a T-tube mounting base 25. A water supply tube 61 connected to the tank 60 is connected to the water supply tube mounting base 24. The water supply tube 61 is inserted through the insertion portion 21 to the tip of the rigid distal end portion 26.

[0023] Further, the operation unit 22 has an opening communicating with the suction channel 27 (see FIG. 3) provided in the insertion portion 21, and the T-tube mounting base 25 is provided at this opening. A T-tube 70 is attached to the T-tube mounting base 25. The T-tube 70 is provided with a fiber attachment port 71 for the laser. The fiber attachment portion 31a of the laser fiber 31 connected to the laser device 30 is attached to the fiber attachment port 71 for the laser. The laser fiber 31 can be inserted into the suction channel 27 via the T-tube 70 and the T-tube mounting base 25.

[0024] Further, the T-tube 70 is provided with a drain base 72. The tube attachment portion 63 of the suction tube 62a is attached to the drain base 72. The T-tube 70 is provided with a cock 73, and the cock 73 causes the water sucked from the suction channel 27 to flow to the suction tube 62a side and prevents it from flowing to the laser fiber attachment port 71 side.

[0025] The suction tube 62a is connected to the secondary strainer 64b via the primary strainer 64a and the suction tube 62b. The secondary strainer 64b is connected to the drainage tank 66 via the suction tube 62c. Note that the suction tubes 62a, 62b, and 62c may also be referred to as the suction tube 62 without distinction. Also, the primary strainer 64a and the secondary strainer 64b may be absent, and the suction tube 62a, the suction tube 62b, and the suction tube 62c may be connected.

[0026] The medical device 10 is provided with a water supply pump 12a and a suction pump 12b. The water supply pump 12a and the suction pump 12b may be constituted by, for example, a tube pump. The water supply pump 12a supplies the liquid filled in the tank 60 to the internal organs of the body via the water supply tube 61. The suction pump 12b is connected to the suction tube 62a via the suction tube 62c, the secondary strainer 64b, the suction tube 62b, and the primary strainer 64a. The negative pressure of the suction tube 62c by the suction pump 12b is transmitted to the suction tube 62a. That is, the liquid sucked from the internal organs of the body by the suction pump 12b is discharged to the drainage tank 66 via the suction channel 27, the suction tube 62a, the primary strainer 64a, the suction tube 62b, the secondary strainer 64a, and the suction tube 62c. Note that the primary strainer 64a and the secondary strainer 64b may also be referred to as the strainer 64 without distinction.

[0027] FIG. 3 and FIG. 4 are explanatory diagrams for explaining the tip of the endoscope insertion portion.

[0028] The rigid distal end portion 26 of the insertion portion 21 is provided with an illumination window (not shown) where the distal end surface of the light guide faces the distal end surface, and an observation window (not shown) for guiding the subject optical image to the light receiving surface of an image pickup device (not shown). In the present embodiment, the distal end opening 61a of the water supply tube 61 is disposed on the distal end surface of the rigid distal end portion 26. The arrows shown at the distal end opening 61a in FIGS. 3 and 4 indicate that the liquid is discharged from the distal end opening 61a of the water supply tube 61. The liquid (physiological saline) stored in the tank 60 is sent from the distal end surface of the rigid distal end portion 26 to the internal organs of the body through the water supply tube 61 inserted into the insertion portion 21 by the water supply pump 12a.

[0029] Also, the distal end opening 27a of the suction channel 27 is disposed on the distal end surface of the rigid distal end portion 26. The arrows shown at the distal end opening 27a in FIGS. 3 and 4 indicate that the liquid in the internal organs of the body is sucked by the suction channel 27. The liquid in the internal organs of the body is discharged to the drainage tank 66 through the suction channel 27, the suction tube 62a, the primary strainer 64a, the suction tube 62b, the secondary strainer 64b, and the suction tube 62c by the suction pump 12b.

[0030] In the present embodiment, an example using the suction channel 27 and the suction tube 62 as the suction pipeline is shown. However, a suction tube is inserted into the suction channel 27, and this suction tube is extended to the outside via the T-shaped tube 70, so that this suction tube can be used as the suction pipeline to drain water from the organ to the outside.

[0031] In the example of FIG. 3, the laser fiber 31 inserted from the T-shaped tube 70 is inserted through the suction channel 27 and is disposed in the suction channel 27 with the tip protruding from the distal end surface of the rigid distal end portion 26. The laser fiber 31 is composed of a core clad 35 and a jacket 36 covering the core clad 35. The laser device 30 irradiates laser light from the tip of the laser fiber 31 via the laser fiber 31.

[0032] When retrieving the stone, as shown in FIG. 3, the laser fiber 31 is inserted into the suction channel 27, and with the tip of the laser fiber 31 protruding from the tip opening 27a, an endoscopic image inside the organ is obtained by the endoscope 20. That is, the illumination light guided by a light guide (not shown) is irradiated onto the subject from an illumination window (not shown) on the front end face of the rigid tip portion 26. The reflected light of the subject passes through an observation window (not shown) and is received by the imaging device. The imaging device acquires an imaging signal based on the optical image of the subject and outputs it to the video processor 40 via a cable (not shown) and the universal code 23 inside the insertion portion 21. The video processor 40 displays an endoscopic image based on the imaging signal on the monitor 50. Thereby, the operator can observe the state inside the organ where the rigid tip portion 26 is disposed on the monitor 50. While looking at the endoscopic image, the operator directs the tip of the laser fiber 31 toward the stone inside the organ and operates the laser device 30 to irradiate the stone with the laser. When irradiated with the laser, the stone is crushed into relatively small fragments.

[0033] In the present embodiment, in the state shown in FIG. 3, by the actions of the water supply pump 12a and the suction pump 12b, water is supplied into the organ while discharging the liquid from the organ. By this perfusion action, the stone inside the organ is sucked into the suction channel 27 through the gap between the laser fiber 31 inserted into the suction channel 27 and the inner surface of the suction channel 27, and is discharged to the suction tube 62a via the T-tube 70.

[0034] When the laser irradiation by the laser fiber 31 is completed, the laser fiber 31 is pulled out from the laser fiber attachment port 71. Thereby, as shown in FIG. 4, the laser fiber 31 is removed from the suction channel 27. Thereafter, the stone is discharged outside the body via the relatively wide suction channel 27.

[0035] Incidentally, since the stone is retrieved with the laser fiber 31 inserted into the suction channel 27, the stone will pass through a relatively narrow drainage channel between the laser fiber 31 and the inner surface of the suction channel 27, and the stone is likely to get caught between the suction channel 27 and the laser fiber 31. Note that the suction channel 27 is a relatively narrow drainage channel. As shown in FIG. 4, even when suction is performed with the laser fiber 31 removed from the suction channel 27, the stone may get caught in the suction channel 27. Once the stone gets caught, subsequent stones will get caught starting from the caught stone, and ultimately the suction channel 27 is likely to become blocked. For example, if such a blockage of the suction channel 27 occurs during the retrieval of a kidney stone, an increase in the renal pelvis pressure may be a concern.

[0036] Therefore, in the present embodiment, it is possible to monitor the perfusion state and detect early that the stone has gotten caught.

[0037] (Configuration of Medical Device 10) In FIG. 2, the medical device 10 includes a control circuit 11, a suction pump 12b, a flow meter 13, a perfusion state detection circuit 14, and a solenoid valve 15. The control circuit 11, the flow meter 13, and the perfusion state detection circuit 14 constitute a perfusion state detection device. In FIG. 2, the primary strainer 64a and the secondary strainer 64b of FIG. 1 are shown as the strainer 64, and the suction tubes 62a, 62b, 62c are shown as the suction tube 62.

[0038] The control circuit 11 and the perfusion state detection circuit 14 may be constituted by a processor using a CPU (Central Processing Unit), an FPGA (Field Programmable Gate Array), or the like. The control circuit 11 and the perfusion state detection circuit 14 may operate according to a program stored in a memory (not shown), or may implement part or all of the functions by an electronic circuit of hardware. Note that the control circuit 11 and the perfusion state detection circuit 14 may be constituted by one processor, or may be constituted by a plurality of processors. The function of the perfusion state detection circuit 14 may be realized by the control circuit 11.

[0039] The control circuit 11 controls each part of the medical device 10. The control circuit 11 generates a drive output for driving the suction pump 12b and outputs it to the suction pump 12b. The suction pump 12b operates based on the drive output to generate a predetermined suction pressure in the suction pipeline formed by the suction channel 27 and the suction tube 62. For example, assuming that the pipeline resistance of the suction pipeline (hereinafter simply referred to as the suction pipeline) formed by the suction channel 27 and the suction tube 62 is constant, the suction pump 12b can flow a liquid with a flow rate approximately proportional to the drive output into the suction pipeline. That is, in this case, the flow rate of the suction pipeline increases or decreases in proportion to the drive output.

[0040] A flow meter 13 is provided in the middle of the suction pipeline formed by the suction tube 62 from the strainer 64 to the suction pump 12b. The flow meter 13 measures the flow rate of the liquid flowing through the suction flow path formed by the suction tube 62 and outputs the measurement result to the control circuit 11 and the perfusion state detection circuit 14. Note that the flow rate flowing through the suction pipeline can be set by a user such as an operator using an input device (not shown). Alternatively, in the control circuit 11, the flow rate flowing through the suction pipeline may be set to a predetermined flow rate.

[0041] In this embodiment, the control circuit 11 performs feedback control such as P (Proportional) I (Integral) D (Derivative) control to change the drive output for the suction pump 12b based on the measurement result of the flow meter 13 in order to maintain the set flow rate (set flow). With this feedback control, even if the pipe resistance of the suction pipe fluctuates somewhat, the flow rate in the suction pipe can be maintained at the user-set flow rate. As a result, perfusion can be performed while keeping the pressure inside the organ constant.

[0042] However, even when the pipe resistance increases due to a stone getting caught in the suction pipe such as the suction channel 27, the drive output for the suction pump 12b also increases in response to the decrease in flow rate due to the increase in pipe resistance, and the flow rate is maintained at the set flow rate. However, when the number of stones getting caught increases and the pipe resistance rises too much, the drive output for the pump 12b reaches the upper limit, the flow rate drops below the set flow rate, and ultimately there is a possibility of a blocked state with a flow rate of 0.

[0043] Therefore, in this embodiment, the perfusion state detection circuit 14 early detects the catching of a stone from the perfusion state. That is, the perfusion state detection circuit 14 is given not only the measurement result of the flow rate from the flow meter 13 but also the drive output from the control circuit 11 or information regarding the drive output (hereinafter simply referred to as the drive output). The perfusion state detection circuit 14 is controlled by the control circuit 11 and detects the perfusion state (hereinafter referred to as the perfusion state) based on the drive output from the control circuit 11 and the measurement result of the flow rate from the flow meter 13, which is based on the water supply into the organ via the water supply tube 61 and the drainage via the suction pipe by the suction channel 27 and the suction tube 62. Based on this detection result, the perfusion state detection circuit 14 determines, for example, whether there is an abnormality in the perfusion state such as whether a stone is caught in the suction pipe. FIG. 5 is an explanatory diagram for explaining the detection of the perfusion state by the perfusion state detection circuit 14. FIG. 5 shows the relationship between the drive output V (V) for the suction pump 12b on the horizontal axis and the flow rate F (mL / min) of the liquid flowing through the suction pipeline on the vertical axis in the V-F plane. As described above, when the pipeline resistance of the suction pipeline is constant, the flow rate F also changes in proportion to the increase or decrease of the drive output for the suction pump 12b. The straight line 81 in FIG. 5 shows the V-F characteristic curve in the case of the pipeline resistance (hereinafter referred to as the initial pipeline resistance) of the suction pipeline in a normal perfusion state.

[0044] That is, when the V-F characteristic obtained from the drive output V obtained from the output of the control circuit 11 and the flow rate F obtained from the output of the flow meter 13 matches the characteristic of the straight line 81, the pipeline resistance of the suction pipeline is considered to be the initial pipeline resistance in the normal state. That is, in this case, it is considered that no increase in pipeline resistance has occurred due to a stone or the like being caught in the suction pipeline. For such detection of the perfusion state, the perfusion state detection circuit 14 obtains the relationship between the drive output V obtained from the output of the control circuit 11 and the flow rate F obtained from the output of the flow meter 13.

[0045] In the present embodiment, the perfusion state detection circuit 14 determines that the change in the pipeline resistance is within the normal range for the range within a predetermined distance (hereinafter referred to as the first determination threshold) from the straight line 81 indicating that the pipeline resistance of the suction pipeline is in the normal state, that is, the normal determination range 82 in FIG. 5. The normal determination range 82 takes into account the variation in pipeline resistance caused by the normal bending of the insertion portion 21 or the like. The range of the normal determination range 82, that is, the magnitude of the first determination threshold, can be appropriately set and changed. By appropriately setting the first determination threshold, it is possible to adjust the degree of snagging determined as abnormal.

[0046] The perfusion state detection circuit 14 determines whether the obtained characteristic value of the driving output V - flow rate F is included within the normal determination range 82. Note that the pipeline resistance of the suction pipeline increases not only due to the entrapment of calculi but also due to buckling of the suction pipeline, adhesion of foreign matter to the tip opening, etc. The perfusion state detection circuit 14 can also detect an abnormality in the perfusion state in such cases.

[0047] The perfusion state detection circuit 14 may be configured to read from a memory (not shown) a first determination threshold for determining whether it is included within the normal determination range 82. A user such as an operator may be able to set and change this first determination threshold using an input device (not shown).

[0048] When perfusion abnormality determination is performed using only the measurement result of the flow rate, it is considered that perfusion abnormality cannot be detected until the occlusion of the suction pipeline progresses to almost complete occlusion by the feedback control of the suction pump 12b. In contrast, in the present embodiment, perfusion abnormality determination is performed by combining the driving output V and the flow rate F, and perfusion abnormality determination can detect perfusion abnormalities even when only a part of the suction pipeline is blocked by a calculus or the like without being affected by complex interference of the flow.

[0049] The suction tube 62 has a bypass portion that branches in the middle of the flow path between the flow meter 13 and the suction pump 12b, and a solenoid valve 15 is connected to the end of this bypass portion. When the solenoid valve 15 is fully open, the suction tube 62 is opened to the atmosphere at the solenoid valve 15, and when it is fully closed, the bypass portion is blocked. The perfusion state detection circuit 14 controls the opening and closing of the solenoid valve 15 based on the determination result of the abnormality of the pipeline resistance as to whether the characteristic value of the driving output V - flow rate F is included within the normal determination range 82. That is, when the perfusion state detection circuit 14 determines that there is no abnormality in the perfusion (pipeline resistance), the solenoid valve is set to the fully closed state, and when it determines that an abnormality has occurred in the perfusion (pipeline resistance), the solenoid valve 15 is set to the fully open state for a moment and then returned to the fully closed state.

[0050] By fully opening the solenoid valve 15 for a moment and then returning it to the fully closed state, a water hammer phenomenon occurs. Note that as the valve that causes such a water hammer phenomenon, various valves can be adopted, not limited to the solenoid valve 15. Due to the water hammer phenomenon caused by the opening and closing of the solenoid valve 15, reverse injection into the fluid in the suction pipeline occurs. As a result, the calculus caught in the suction pipeline is detached from the suction pipeline by the pressure of the liquid due to the reverse injection, and the catching of the calculus in the suction pipeline is eliminated.

[0051] Note that when the perfusion state detection circuit 14 determines that an abnormality has occurred in the pipeline resistance, it may be configured to output warning information indicating that there is a possibility that the suction pipeline is blocked. For example, the monitor 50 may be configured to display a warning indication based on this warning information.

[0052] Next, the operation of the embodiment configured as described above will be described with reference to FIGS. 5 and 6. FIG. 6 is a flowchart for explaining the perfusion control of the medical device 10.

[0053] In step S1 of FIG. 6, the control circuit 11 maintains the flow rate F at the set flow rate by performing PID control on the drive output V for the suction pump 12b. Note that the control circuit 11 also performs PID control to maintain the set flow rate for the water supply pump 12a. In the present embodiment, the control circuit 11 performs the processing after step S2 in parallel with the control in step S1. Note that the processing after step S2 is performed by the perfusion state detection circuit 14 under the control of the control circuit 11. The flow meter 13 measures the flow rate F of the liquid flowing through the suction pipeline and outputs the measurement result to the control circuit 11 and the perfusion state detection circuit 14. The control circuit 11 performs PID control on the drive output V based on the measurement result of the flow rate F (S1). The control circuit 11 gives the drive output V set for the suction pump 12b to the perfusion state detection circuit 14. The flow rate F and the drive output V are input to the perfusion state detection circuit 14 (S2).

[0054] In step S3, the perfusion state detection circuit 14 calculates the distance L between the normal V-F function in the V-F plane shown by the straight line 81 in FIG. 5 and the coordinate values of the obtained drive output V and flow rate F. The perfusion state detection circuit 14 determines whether the distance L exceeds a first determination threshold value (step S4).

[0055] Now, for example, assume that the coordinate values in the V-F plane of the drive output V and the flow rate F obtained by the perfusion state detection circuit 14 are as shown by the circled number 1 in FIG. 5. The set flow rate is assumed to be the set flow rate shown in FIG. 5. The control circuit 11 performs feedback control on the drive output V based on the measurement result of the flow meter 13 in order to maintain this set flow rate (S1). By this control, if there is no change in the pipeline resistance of the suction pipeline, the drive output V - flow rate F takes the coordinate values on the straight line 81 in FIG. 5 in response to the change in the set flow rate.

[0056] Here, for example, assume that the pipeline resistance of the suction pipeline increases from the initial pipeline resistance due to reasons such as the normal bending operation of the insertion portion 21. Then, as shown by the circled number 2 in FIG. 5, if the drive output V does not change, the flow rate F decreases. However, due to the feedback control by the control circuit 11, the drive output V increases, and the flow rate F returns to the set flow rate as shown by the circled number 3 in FIG. 5 regardless of the change in the pipeline resistance. When the pipeline resistance increases due to the normal bending operation of the insertion portion 21 or the like, the pipeline resistance may return to the original initial pipeline resistance. In this case, due to the feedback control by the control circuit 11, the drive output V and the flow rate F return to the coordinate values of the circled number 1.

[0057] However, when the increase in the initial pipeline resistance is due to the snagging of a calculus in the suction pipeline or the like, the number of snared calculi may increase starting from the first snagged calculus, so the pipeline resistance may further increase. Then, as shown by the circled number 4 in FIG. 5, the flow rate F decreases, and the drive output V increases by the feedback control of the control circuit 11 (circled number 5), and the set flow rate is maintained.

[0058] In this embodiment, when the relationship between the driving output V and the flow rate F deviates from the normal determination range 82, that is, when the distance L between the coordinates of the driving output V - flow rate F and the straight line 81 exceeds the first determination threshold, it is determined that an abnormality has occurred in the perfusion, that is, a stone has become caught (YES determination in S4). When the perfusion state detection circuit 14 determines that the distance L is within the first determination threshold (NO determination in S4), the process returns from step S4 to step S2.

[0059] That is, in the example of FIG. 5, when the coordinate values of the driving output V - flow rate F become the circled numbers 4 and 5, the perfusion state detection circuit 14 determines in step S5 that a stone has become caught in the suction line. When the flow rate does not return to the set flow rate even by PID control, or when many stones are caught in a short time, etc., the driving output V - flow rate F may change to the coordinate positions of the circled numbers 1 to 6 in FIG. 5. Even in such cases, the perfusion state detection circuit 14 can determine that a stone has become caught in a short time from the occurrence of such malfunctions.

[0060] It is also conceivable that even when the driving output V reaches the maximum value by PID control by the control circuit 11, the flow rate does not return to the set flow rate and the driving output V - flow rate F becomes the coordinate position of the circled number 7 in FIG. 5. Even in this case, the perfusion state detection circuit 14 can determine that a stone has become caught before the suction line becomes completely blocked.

[0061] In the next step S6, the perfusion state detection circuit 14 outputs warning information indicating that there may be an obstruction. In the next step S7, the perfusion state detection circuit 14 fully opens the solenoid valve 15 to open the suction line to the atmosphere, waits for a set time in step S8, and then returns the solenoid valve 15 to the fully closed state in step S9. Then, a water hammer phenomenon occurs and back injection occurs in the suction line. As a result, the stone caught in the suction line comes off and the entrapment of the stone in the suction line is eliminated.

[0062] In step S10, the perfusion state detection circuit 14 waits for a predetermined time until the influence of the reverse injection on the pipeline resistance disappears, and then returns the process to step S2 to continue detecting the perfusion state. Thereafter, the same operation is repeated.

[0063] As described above, in this embodiment, by detecting the perfusion state based on the relationship between the flow rate flowing through the suction pipeline for discharging the calculus outside the body and the pump drive output, it is possible to detect early that the calculus has become caught. That is, it is possible to detect early a slight catching of the calculus before the suction pipeline becomes blocked, and it becomes possible to take measures to eliminate that state. For example, in this embodiment, when an abnormality in the perfusion state is detected, it is possible to generate a reverse injection by means of a water hammer action by opening the suction pipeline to the atmosphere, and remove the calculus caught in the suction pipeline. Thereby, it is possible to surely prevent the suction pipeline from becoming blocked.

[0064] In the first embodiment, an example of detecting the perfusion state based on the relationship between the drive output V and the flow rate F has been shown. However, since the suction pump is under PID control, if the set value of the flow rate is constant, it is also possible to simply compare the drive output V of the pump with a predetermined threshold value, and detect an abnormality in the perfusion state depending on whether the drive output V exceeds the predetermined threshold value.

[0065] Also, in FIG. 2, a reverse injection was generated by opening and then closing the solenoid valve 15 that opens the suction pipeline to the atmosphere. However, in the normal state, a valve that is in the open state is provided in the middle of the flow path of the suction pipeline, and it is also possible to configure it to generate a reverse injection by closing and then reopening the valve.

[0066] (Modification example) FIG. 7 is an explanatory diagram for explaining the operation of a modified example. The hardware configuration of this modified example is the same as that of the first embodiment, and the method for detecting an abnormality in the perfusion state is also the same as that of the first embodiment. In this modified example, in order to prevent blockage of the suction line, the suction line is opened to the atmosphere at predetermined intervals to cause back injection due to the water hammer effect. FIG. 7 shows the control in this modified example with time on the horizontal axis and flow rate F on the vertical axis.

[0067] FIG. 8 is a flowchart for explaining the operation in this modified example. In FIG. 8, the same steps as those in FIG. 6 are denoted by the same reference numerals and the description thereof is omitted.

[0068] In step S11 of FIG. 8, the perfusion state detection circuit 14 determines whether or not periodic back injection is set. For example, the control circuit 11 can set a mode of performing periodic back injection (periodic back injection ON) and a mode of not performing periodic back injection (periodic back injection OFF) according to the operation of the operator or a predetermined sequence. Now, it is assumed that periodic back injection OFF is set. The perfusion state detection circuit 14 shifts to step S15 based on the NO determination in step S11 and performs perfusion state detection and warning processing. The processing in step S15 is the same as the processing in steps S2 to S6 of FIG. 6. That is, the perfusion state detection circuit 14 determines whether or not the detection results of the drive output V and the flow rate F have exceeded the normal determination range 82, that is, whether or not the distance L between the normal V-F characteristic curve (straight line 81) in the V-F plane and the coordinates of the measured drive output V - flow rate F exceeds the first determination threshold, thereby detecting an abnormality in the perfusion state.

[0069] The perfusion state detection circuit 14 determines whether or not an abnormality in the perfusion state has been detected in the next step S16. If the perfusion state detection circuit 14 has not detected an abnormality in the perfusion state (NO determination in step S16), the process returns to step S11. As shown in the first perfusion state detection period in FIG. 7, in a state where no stone is caught in the suction line, steps S11, S15, and S16 are repeated. In this case, the flow rate F is maintained at the set flow rate by PID control by the control circuit 11 as shown in FIG. 7.

[0070] Next, as shown in FIG. 7, it is assumed that it is set to periodic back-injection ON. Then, the perfusion state detection circuit 14 proceeds to step S12 by the YES determination in step S11 and determines whether it is the timing of back-injection. For example, the periodic back-injection is performed at a predetermined period, and the perfusion state detection circuit 14 recognizes the timing of back-injection based on whether the predetermined period has elapsed. As shown in FIG. 7, when it is set to periodic back-injection ON, the first back-injection is performed immediately thereafter.

[0071] That is, the perfusion state detection circuit 14 proceeds to step S13 by the YES determination in step S12 and performs back-injection. The back-injection in step S13 is the same process as steps S7 to S9 in FIG. 6. In FIG. 7, it shows that the suction line is opened to the atmosphere and back-injection is performed by the state of the solenoid valve being opened only for a short time. As shown in FIG. 7, by executing the back-injection, the flow rate F becomes negative for an instant. The negative flow rate F means that the liquid flows in the opposite direction to normal in the suction line. Thereby, the entrapment of the calculus may be released.

[0072] The perfusion state detection circuit 14 waits for a specified time in the next step S14 and then detects the perfusion state in step 15. As shown in FIG. 7, since the flow rate is significantly separated from the set flow rate by the back-injection, the perfusion state cannot be correctly detected using the drive output V and the flow rate F until the influence of the back-injection is removed. Therefore, the perfusion state detection circuit 14 performs perfusion state detection after the influence of the back-injection becomes sufficiently small and the flow rate returns to the set flow rate. If no abnormality in the perfusion state is detected, the process returns from step S16 to step S11 and the same process is repeated.

[0073] Here, it is assumed that something like a stone gets caught in the suction pipeline. Then, as a result of the perfusion state detection in step S15, an abnormality in the perfusion state is detected. In this case, the perfusion state detection circuit 14 shifts the process from step S16 to step S17 and performs reverse injection. The reverse injection in step S17 is also the same process as steps S7 to S9 in FIG. 6.

[0074] In the next step S18, the perfusion state detection circuit 14 determines whether the reverse injection has been performed the specified number of times. If the reverse injection does not reach the specified number of times, the perfusion state detection circuit 14 returns the process to step S17 and continues the reverse injection. In the example of FIG. 7, an abnormality in the perfusion state is detected because the flow rate F during the perfusion state detection period has decreased relatively significantly compared to the set flow rate. As a result, it shows that the reverse injection has been performed three times. If three times is set as the specified number of times, when the three - time reverse injection is completed, the perfusion state detection circuit 14 returns the process to step S14. Thus, the same process is repeated hereafter. In the example of FIG. 7, it shows that the three - time continuous reverse injection has been performed twice.

[0075] Note that in the flow of FIG. 8, even when the regular reverse injection is OFF, if an abnormality in the perfusion state is determined in step S16, the reverse injection is continuously executed the specified number of times by steps S17 and S18. It may be possible to change the continuous number of times of reverse injection between when the regular reverse injection is ON and when the regular reverse injection is OFF.

[0076] Thus, in this modification example, by constantly performing the reverse injection, the blockage of the suction pipeline can be effectively prevented. Also, if the stone does not come off even by the constant reverse injection, continuous reverse injection is performed, and it is possible to surely prevent the blockage of the suction pipeline.

[0077] (Modification example) FIG. 9 is a flowchart for explaining the operation of another modified example. The hardware configuration of this modified example is the same as that of the first embodiment, and the method for detecting an abnormality in the perfusion state is also the same as that of the first embodiment. In this modified example, when an abnormality in the perfusion state is detected, the water supply amount is decreased. For the same procedures as those in FIG. 6 in FIG. 9, the same reference numerals are given and the description thereof is omitted.

[0078] When it is detected in the perfusion state detection circuit 14 that an abnormality has occurred in the perfusion state as a result of a calculus being caught in the suction pipeline, reverse injection is performed in steps S7 to S9. As a result, the catching of the calculus may be removed. However, if the flow rate F of the suction pipeline decreases during the period until the catching of the stone is completely removed, the amount of water in the organ may increase and the internal pressure of the organ may also increase. Therefore, in this modified example, when it is detected in the perfusion state detection circuit 14 that an abnormality has occurred in the perfusion state, the water supply amount by the water supply pump 12a is decreased to suppress an increase in the internal pressure of the organ.

[0079] The flow in FIG. 9 is different from the flow in FIG. 6 in that the processes of steps S21 and S22 are added. Step S21 is a process of decreasing the output of the water supply pump 12a when an abnormality in the perfusion state is detected with the distance L exceeding the first determination threshold value. When the control circuit 11 is given a detection result indicating an abnormality in the perfusion state by the perfusion state detection circuit 14, the control circuit 11 controls the water supply pump 12a to decrease its output. As a result, the water supply amount of the liquid supplied into the organ is decreased, and an increase in the internal pressure of the organ is prevented.

[0080] When it is determined by the perfusion state detection circuit 14 that the perfusion state has returned to normal (NO determination in step S4), the control circuit 11 sets the output of the water supply pump 12a to the original user setting value in step S22, and then returns the process to step S2.

[0081] As described above, according to this modified example, an increase in the internal pressure of the organ can be prevented.

[0082] Note that although the modification example in Fig. 9 shows an example applied to the first embodiment in Fig. 6, it can also be applied to the modification example in Fig. 8.

[0083] (Second Embodiment) Fig. 10 is a block diagram showing a second embodiment of the present invention. In Fig. 10, the same components as those in Fig. 2 are denoted by the same reference numerals and the description thereof is omitted. This embodiment enables early detection of a snagged stone by detecting the perfusion state based on the relationship between the flow rate flowing through the suction pipeline and the suction pressure.

[0084] The medical device 10A in this embodiment is different from the medical device 10 in Fig. 2 in that a pressure gauge 16 is added and the output of the pressure gauge 16 is supplied to the perfusion state detection circuit 14 instead of the drive output V. Other configurations are the same as those in the first embodiment. This embodiment is different from the first embodiment in the method of detecting the perfusion state. The pressure gauge 16 measures the pressure in the suction pipeline and outputs the measurement result to the perfusion state detection circuit 14.

[0085] Fig. 11 is an explanatory diagram for explaining the method of detecting the perfusion state of the perfusion state detection circuit 14 in the second embodiment. Fig. 11 shows the relationship between the suction pressure P and the flow rate F on the P-F plane with the suction pressure P (kPa) by the suction pump 12b on the horizontal axis and the flow rate F (mL / min) of the liquid flowing through the suction pipeline on the vertical axis. When the pipeline resistance of the suction pipeline is constant, the flow rate F also changes in proportion to the increase or decrease of the suction pressure P by the suction pump 12b. The straight line 85 in Fig. 11 shows the P-F characteristic curve at the initial pipeline resistance in a normal perfusion state.

[0086] That is, when the P-F characteristic obtained from the output of the pressure gauge 16 and the flow rate F obtained from the output of the flow meter 13 matches the characteristic of the straight line 85, the pipeline resistance of the suction pipeline is considered to be the initial pipeline resistance in the normal state. That is, in this case, it is considered that there is no increase in pipeline resistance due to stones or the like being caught in the suction pipeline. For detecting such a perfusion state, the perfusion state detection circuit 14 obtains the relationship between the suction pressure P obtained from the output of the pressure gauge 16 and the flow rate F obtained from the output of the flow meter 13.

[0087] In the present embodiment, for the range within a predetermined distance (hereinafter referred to as the second determination threshold) from the straight line 85 indicating that the pipeline resistance of the suction pipeline is in the normal state, that is, the normal determination range 86 in FIG. 11, it is determined that the change in the pipeline resistance is within the normal range. The normal determination range 86 takes into account fluctuations in pipeline resistance due to normal bending of the insertion portion 21 and the like. The range of the normal determination range 86, that is, the magnitude of the second determination threshold, can be appropriately set and changed. By appropriately setting the second determination threshold, it is possible to adjust the degree of snagging determined as abnormal.

[0088] The perfusion state detection circuit 14 determines whether or not the obtained characteristic value of the suction pressure P - flow rate F is included within the normal determination range 86. Note that the perfusion state detection circuit 14 may be configured to read a second determination threshold for determining whether or not it is included within the normal determination range 86 from a memory (not shown). A user such as a surgeon may be able to set and change this second determination threshold using an input device (not shown).

[0089] Also in the present embodiment, perfusion abnormality determination is performed by combining the suction pressure P and the flow rate F, and perfusion abnormality determination can detect perfusion abnormalities such as when only a part of the suction pipeline is blocked by stones or the like without being affected by complex interference of the flow.

[0090] Next, the operation of the embodiment configured as described above will be described with reference to FIGS. 11 and 12. FIG. 12 is a flowchart for explaining the perfusion control of the medical device 10A. In FIG. 12, the same steps as those in FIG. 6 are denoted by the same reference numerals and the description thereof is omitted. The flow in FIG. 12 differs from the flow in FIG. 6 in that steps S31 and S32 are adopted instead of steps S3 and S4, respectively.

[0091] Now, for example, assume that the coordinate values in the P-F plane of the suction pressure P and the flow rate F obtained in the perfusion state detection circuit 14 are indicated by the circled number 1 in FIG. 11. The set flow rate is assumed to be the set flow rate shown in FIG. 11. In order to maintain this set flow rate, the control circuit 11 performs feedback control of the suction pressure P based on the measurement result of the flow meter 13 (step S1 in FIG. 12). By this control, if there is no change in the pipeline resistance of the suction pipeline, the suction pressure P-flow rate F takes the coordinate values on the straight line 85 in FIG. 11 in accordance with the change in the set flow rate.

[0092] Here, for example, assume that the pipeline resistance of the suction pipeline increases from the initial pipeline resistance due to reasons such as the normal bending operation of the insertion portion 21. Then, as shown by the circled number 2 in FIG. 11, if the suction pressure P does not change, the flow rate F decreases. However, by the feedback control by the control circuit 11, the suction pressure P increases (the negative pressure increases), and the flow rate F returns to the set flow rate as shown by the circled number 3 in FIG. 11 regardless of the change in the pipeline resistance. When the pipeline resistance increases due to the normal bending operation of the insertion portion 21 or the like, the pipeline resistance may return to the original initial pipeline resistance. In this case, by the feedback control by the control circuit 11, the suction pressure P and the flow rate F return to the coordinate values of the circled number 1.

[0093] However, when the increase in the initial pipeline resistance is caused by, for example, the entrapment of a stone in the suction pipeline, the number of stones caught may increase starting from the first caught stone, and thus the pipeline resistance may further increase. Then, as shown by the circled number 4 in FIG. 11, the flow rate F decreases, and the suction pressure P increases (circled number 5) by the feedback control of the control circuit 11, and the set flow rate is maintained.

[0094] In this embodiment, the perfusion state detection circuit 14 calculates the distance L between the coordinates of the suction pressure P - flow rate F and the straight line 85 in step S31 of FIG. 11. When the relationship between the suction pressure P - flow rate F deviates from the normal determination range 86, that is, when the distance L between the coordinates of the suction pressure P - flow rate F and the straight line 85 exceeds the second determination threshold, the perfusion state detection circuit 14 determines that an abnormality has occurred in the perfusion, that is, a stone has become stuck (YES determination in S32). When the perfusion state detection circuit 14 determines that the distance L is within the second determination threshold (NO determination in S32), the process returns from step S32 to step S2.

[0095] In the example of FIG. 11, when the coordinate values of the suction pressure P - flow rate F become the round numbers 4 and 5, the perfusion state detection circuit 14 determines in step S5 that a stone has become stuck in the suction pipeline. When the flow rate does not return to the set flow rate even by PID control, or when many stones become stuck in a short time, etc., the suction pressure P - flow rate F may change to the coordinate positions of the round numbers 1 to 6 in FIG. 11. Even in such cases, the perfusion state detection circuit 14 can determine that a stone has become stuck from the occurrence of such malfunctions in a short time.

[0096] It is also conceivable that even when the suction pressure P reaches the maximum value by PID control by the control circuit 11 and the flow rate does not return to the set flow rate, and the suction pressure P - flow rate F becomes the coordinate position of the round number 7 in FIG. 11. Even in this case, the perfusion state detection circuit 14 can determine that a stone has become stuck before the suction pipeline becomes completely blocked.

[0097] The processing when the perfusion state detection circuit 14 detects an abnormality in the perfusion state, such as when a stone has become stuck, is the same as that in the first embodiment.

[0098] Thus, in this embodiment, by detecting the perfusion state based on the relationship between the flow rate and the suction pressure flowing through the suction pipeline for discharging the calculus outside the body, it is possible to detect at an early stage that the calculus has become caught. Other effects are the same as those of the first embodiment.

[0099] Note that the modified examples of FIGS. 7, 8, and 9 may be applied to this embodiment.

[0100] In addition, in the second embodiment, an example of detecting the perfusion state based on the relationship between the suction pressure P and the flow rate F has been shown. However, since the suction pump is under PID control, if the set value of the flow rate is constant, it is also possible to simply compare the suction pressure P with a predetermined threshold value, and detect an abnormality in the perfusion state based on whether the suction pressure P exceeds the predetermined threshold value.

[0101] (Modified Example) FIG. 13 is a block diagram showing another modified example. In FIG. 13, the same components as those in FIG. 11 are denoted by the same reference numerals and the description thereof is omitted.

[0102] The example of FIG. 13 employs a medical device 10B in which the pressure gauge 16 is omitted from the medical device 10A, and uses a pressure gauge 16A provided outside the medical device 10B to detect the suction pressure of the suction pipeline.

[0103] Other configurations, operations, and effects are the same as those of the embodiment of FIG. 10.

[0104] (Modified Example) FIG. 14 is a block diagram showing another modified example. In FIG. 14, the same components as those in FIGS. 2 and 10 are denoted by the same reference numerals and the description thereof is omitted. This modified example combines the first and second embodiments to perform both abnormality detection of the perfusion state based on the relationship between the drive output V - flow rate F and abnormality detection of the perfusion state based on the relationship between the suction pressure P - flow rate F.

[0105] The medical device 10C in FIG. 14 is different from the medical devices 10 and 10A in FIGS. 2 and 10 in that the perfusion state detection circuit 14 is supplied with the flow rate F from the flow meter 13, the drive output V from the control circuit 11, and the suction pressure P from the pressure gauge 16. The perfusion state detection circuit 14 detects an abnormality in the perfusion state using the relationship between the drive output V and the flow rate F, and also detects an abnormality in the perfusion state using the relationship between the suction pressure P and the flow rate F.

[0106] Next, the operation of the embodiment configured as described above will be described with reference to FIG. 15. FIG. 15 is a flowchart for explaining the operation of a modified example of FIG. 14. In FIG. 15, the same steps as those in FIGS. 6 and 12 are denoted by the same reference numerals and the description thereof is omitted.

[0107] The flow meter 13 measures the flow rate F of the liquid flowing through the suction line and outputs the measurement result to the control circuit 11 and the perfusion state detection circuit 14. The control circuit 11 gives the drive output V set for the suction pump 12b to the perfusion state detection circuit 14. Further, the pressure gauge 16 measures the suction pressure P of the suction line and gives it to the perfusion state detection circuit 14. Thus, the flow rate F, the drive output V, and the suction pressure P are input to the perfusion state detection circuit 14 (step S41 in FIG. 15).

[0108] In step S42, the perfusion state detection circuit 14 calculates the distance L1 between the normal V-F function in the V-F plane shown by the straight line 81 in FIG. 5 and the coordinate values of the obtained drive output V and flow rate F, and calculates the distance L2 between the normal P-F function in the P-F plane shown by the straight line 85 in FIG. 11 and the coordinate values of the obtained suction pressure P and flow rate F.

[0109] The perfusion state detection circuit 14 determines whether the distance L1 exceeds a first determination threshold value and also determines whether the distance L2 exceeds a second determination threshold value. When the distance L1 exceeds the first determination threshold value and / or the distance L2 exceeds the second determination threshold value, the perfusion state detection circuit 14 determines that an abnormality in the perfusion state has occurred (YES determination in step S43) and transfers the process to step S5. Further, when the distance L1 is within the first determination threshold value and the distance L2 is within the second determination threshold value, the perfusion state detection circuit 14 determines that no abnormality has occurred in the perfusion state (NO determination in step S43) and returns the process to step S41.

[0110] Other operations are the same as the flows in FIGS. 6 and 12.

[0111] As described above, in this modified example, the abnormality in the perfusion state is determined using both the detection results of the abnormality detection of the perfusion state based on the relationship between the drive output V - flow rate F and the abnormality detection of the perfusion state based on the relationship between the suction pressure P - flow rate F. Even if the snagging of the calculus is more minor, it is possible to detect the snagging at an early stage.

[0112] (Third Embodiment) FIG. 16 is a block diagram showing a third embodiment of the present invention. In FIG. 16, the same components as those in FIG. 14 are denoted by the same reference numerals and the description thereof is omitted. In this embodiment, by detecting the perfusion state based on the relationship between the suction pressure of the suction pipeline for discharging the calculus to the outside of the body and the drive output for the suction pump 12b, it is possible to detect at an early stage that the calculus has become snagged.

[0113] The medical device 10D in this embodiment is different from the medical device 10A in FIG. 10 in that the flow meter 13 is omitted and the control circuit 11 does not perform PID control. Other configurations are the same as those in the modified example of FIG. 14. In this embodiment, the method of detecting the perfusion state is different from those in the above embodiments.

[0114] FIG. 17 is an explanatory diagram for explaining a method of detecting the perfusion state of the perfusion state detection circuit 14 in the third embodiment. FIG. 17 shows the relationship between the suction pressure P (kPa) by the suction pump 12b on the horizontal axis and the drive output V (V) for the suction pump 12b on the vertical axis in the P-V plane. In the present embodiment, the control circuit 11 does not perform PID control for feeding back the flow rate of the liquid flowing through the suction pipeline, but outputs the drive output V according to the user setting to the suction pump 12b.

[0115] When the pipeline resistance of the suction pipeline is constant, the suction pressure P by the suction pump 12b changes in proportion to the increase or decrease of the drive output V for the suction pump 12b. The straight line 91 in FIG. 17 shows the P-V characteristic curve at the initial pipeline resistance in the state where the perfusion state is normal.

[0116] That is, when the P-V characteristic by the suction pressure P obtained from the output of the pressure gauge 16 and the drive output V based on the output of the control circuit 11 matches the characteristic of the straight line 91, the pipeline resistance of the suction pipeline is considered to be the initial pipeline resistance in the normal state. That is, in this case, it is considered that there is no increase in the pipeline resistance due to a stone or the like being caught in the suction pipeline. For such detection of the perfusion state, the perfusion state detection circuit 14 obtains the relationship between the suction pressure P obtained from the output of the pressure gauge 16 and the drive output V obtained from the output of the control circuit 11.

[0117] In the present embodiment, for the range within a predetermined distance (hereinafter referred to as the third determination threshold) from the straight line 91 indicating that the pipeline resistance of the suction pipeline is in the normal state, that is, the normal determination range 92 in FIG. 17, it is determined that the change in the pipeline resistance is within the normal range. The normal determination range 92 takes into account fluctuations in the pipeline resistance caused by normal bending of the insertion portion 21. The range of the normal determination range 92, that is, the magnitude of the third determination threshold can be appropriately set and changed. By appropriately setting the third determination threshold, it is possible to adjust the degree of snagging determined as abnormal.

[0118] The perfusion state detection circuit 14 determines whether the obtained characteristic value of the suction pressure P - drive output V is included within the normal determination range 92. Note that the perfusion state detection circuit 14 may be configured to read from a memory (not shown) a third determination threshold for determining whether it is included within the normal determination range 92. A user such as an operator may be able to set and change this third determination threshold using an input device (not shown).

[0119] Also in this embodiment, perfusion abnormality determination is performed by combining the suction pressure P and the drive output V, and it is possible to detect perfusion abnormalities such as when only a part of the suction line is blocked by a calculus or the like without the perfusion abnormality determination being affected by complex interference of the flow.

[0120] In the embodiment configured as described above, an abnormality in the perfusion state is detected by the same flow as in the above embodiments.

[0121] Now, for example, assume that the coordinate values in the P - V plane of the suction pressure P and the drive output V obtained in the perfusion state detection circuit 14 are as indicated by the circled number 1 in FIG. 17. Note that the set flow rate is the set flow rate shown in FIG. 17. The control circuit 11 is not performing PID control, and the drive output V for the suction pump 12b is a user - set value. In the example of FIG. 17, for example, in the initial pipeline resistance, it is assumed that the drive output V for obtaining the set flow rate is set.

[0122] Here, for example, assume that the pipeline resistance of the suction line increases from the initial pipeline resistance due to reasons such as the normal bending operation of the insertion portion 21. Then, as shown by the circled number 2 in FIG. 17, the suction pressure P increases (the negative pressure increases). Note that when the pipeline resistance increases due to the normal bending operation of the insertion portion 21 or the like, the pipeline resistance may return to the original initial pipeline resistance. In this case, the suction pressure P and the drive output V return to the coordinate values of the circled number 1.

[0123] However, when the increase in the initial pipeline resistance is caused by, for example, a stone getting caught in the suction pipeline, the number of stones getting caught may increase starting from the first caught stone, and thus the pipeline resistance may further increase. Then, as shown by the circled number 3 in Fig. 17, the suction pressure P further increases.

[0124] In this embodiment, the perfusion state detection circuit 14 calculates the distance L between the coordinates of the suction pressure P - drive output V and the straight line 91. When the relationship between the suction pressure P - drive output V deviates from the normal determination range 92, that is, when the distance L between the coordinates of the suction pressure P - drive output V and the straight line 91 exceeds the third determination threshold, the perfusion state detection circuit 14 determines that an abnormality has occurred in the perfusion, that is, a stone has become caught. Note that when the perfusion state detection circuit 14 determines that the distance L is within the third determination threshold, it determines that the perfusion state is normal.

[0125] In the perfusion state detection circuit 14, the processing when an abnormality in the perfusion state such as a stone getting caught is detected is the same as in the above embodiments.

[0126] Thus, in this embodiment, by detecting the perfusion state based on the relationship between the suction pressure and the drive output of the suction pipeline for discharging the stone outside the body, it is possible to detect early that a stone has become caught. Other effects are the same as in the above embodiments.

[0127] In the third embodiment, an example of detecting the perfusion state based on the relationship between the suction pressure P and the drive output V is shown. However, if the set value of the drive output V is constant, it is also possible to simply compare the suction pressure P with a predetermined threshold and detect an abnormality in the perfusion state based on whether the suction pressure P exceeds the predetermined threshold. Also, even when the suction pump is PID - controlled, it is possible to detect the perfusion state based on the relationship between the suction pressure P and the drive output V.

[0128] The present invention is not limited to the above-described embodiments as they are, and at the implementation stage, the components can be modified and embodied without departing from the gist thereof. Further, various inventions can be formed by appropriately combining a plurality of components disclosed in the above-described embodiments. For example, some of the components shown in the embodiments may be deleted. Furthermore, components from different embodiments may be appropriately combined.

[0129] For example, in each of the above-described embodiments, an example of early detection of an abnormality in the perfusion state in the suction pipeline was described, but the present invention is similarly applicable to early detection of an abnormality in the perfusion state in the water supply pipeline.

Claims

A method for operating a perfusion state detection device comprising a water supply pump for supplying a liquid via a water supply pipeline inserted into a living body, a suction pump for discharging the liquid via a suction pipeline inserted into the living body, and a processor, comprising: the processor: driving the water supply pump; driving the suction pump; determining a distance between coordinates on the plane defined by any two of the drive output for the suction pump, the flow rate of the liquid flowing through the suction pipeline, and the pressure in the suction pipeline, and the coordinates on the plane actually measured, in a plane showing the relationship between the two values in the normal perfusion state of the suction pipeline; detecting an abnormality in the perfusion state of the suction pipeline based on whether the distance exceeds a threshold value, and controlling the flow of the liquid in the suction pipeline based on the detection result of the perfusion state; A method for operating a perfusion state detection device, characterized by the above. According to claim 2, the processor: has a step of causing a reverse injection in the suction pipeline in order to control the flow of the liquid in the suction pipeline. A method for operating a perfusion state detection device according to claim 1, characterized by the above. According to claim 3, the processor: has a step of reducing the amount of the liquid flowing through the water supply pipeline in order to control the flow of the liquid in the water supply pipeline. A method for operating a perfusion state detection device according to claim 2, characterized by the above. According to claim 4, the processor: has a step of controlling the opening and closing of a valve for causing a water hammer effect in the suction pipeline in order to cause a reverse injection in the suction pipeline. A method for operating a perfusion state detection device according to claim 2, characterized by the above. According to claim 5, the processor: has a step of performing feedback control to keep the flow rate constant by controlling the drive output of the suction pump based on the flow rate. A method for operating a perfusion state detection device according to claim 1, characterized by the above. According to claim 6, the processor: has a step of opening the valve when a detection result indicating that the perfusion state is abnormal is obtained in the closed state of the valve. A method for operating a perfusion state detection device according to claim 4, characterized by the above. According to claim 7, the processor: has a step of closing the valve when a detection result indicating that the perfusion state is abnormal is obtained in the open state of the valve. A method for operating a perfusion state detection device according to claim 4, characterized by the above.

8. The processor obtains a measurement result of the flow rate of the liquid flowing through the suction pipeline; in a drive output-flow rate plane showing the relationship between the drive output of the suction pump and the flow rate, a coordinate on the drive output-flow rate plane formed by the drive output and the flow rate in the normal perfusion state of the suction pipeline, and a coordinate on the drive output-flow rate plane formed by the actual drive output and the flow rate, and obtains a distance therebetween; determines whether the perfusion state is abnormal based on whether the distance exceeds a first threshold value. The method for operating a perfusion state detection device according to claim 1, characterized in that.

9. The processor obtains a measurement result of the flow rate of the liquid flowing through the suction pipeline; in a pressure-flow rate plane showing the relationship between the pressure and the flow rate, a coordinate on the pressure-flow rate plane formed by the pressure and the flow rate in the normal perfusion state of the suction pipeline, and a coordinate on the pressure-flow rate plane formed by the actual pressure and the flow rate, and obtains a distance therebetween; determines whether the perfusion state is abnormal based on whether the distance exceeds a second threshold value. The method for operating a perfusion state detection device according to claim 1, characterized in that.

10. The processor obtains a measurement result of the pressure of the liquid flowing through the suction pipeline; in a pressure-drive output plane showing the relationship between the pressure and the drive output of the suction pump, a coordinate on the pressure-drive output plane formed by the pressure and the drive output of the suction pump in the normal perfusion state of the suction pipeline, and a coordinate on the pressure-drive output plane formed by the actual pressure and the drive output of the suction pump, and obtains a distance therebetween; determines whether the perfusion state is abnormal based on whether the distance exceeds a third threshold value. The method for operating a perfusion state detection device according to claim 1, characterized in that.

11. a water supply pipeline inserted into a living body for supplying liquid to the living body; a water supply pump for supplying the liquid to the water supply pipeline; a suction pipeline inserted into the living body for sucking the liquid from the living body; a suction pump for discharging the liquid from the living body through the suction pipeline; a valve for generating a reverse injection due to a water hammer action in the suction pipeline; a processor, and is provided with; The processor the drive output for the suction pump, the flow rate of the liquid flowing through the suction pipeline, and the suction pipeline In a plane showing the relationship between any two values of the suction pressure, determine the distance between the coordinates on the plane formed by the two values in the normal perfusion state of the suction pipeline and the coordinates on the actually measured plane. Detect an abnormality in the perfusion state of the suction pipeline based on whether the distance exceeds a first threshold value. Based on the detection result of the perfusion state, control the opening and closing of the valve to cause the reverse injection in the suction pipeline. A perfusion state detection device characterized by the above.

12. The suction pipeline has a bypass section. The valve is connected to the end of the bypass section, and the reverse injection is caused by opening the suction pipeline. The perfusion state detection device according to claim 11, characterized by the above.

13. It has a flow meter provided in the suction pipeline for measuring the flow rate of the liquid flowing through the suction pipeline. The processor In a drive output-flow rate plane showing the relationship between the drive output and the flow rate, determine the distance between the coordinates on the drive output-flow rate plane formed by the drive output and the flow rate in the normal perfusion state of the suction pipeline and the coordinates on the drive output-flow rate plane formed by the actual drive output and the flow rate. Determine the abnormality of the perfusion state based on whether the distance exceeds a first threshold value. The perfusion state detection device according to claim 11, characterized by the above.

14. It has a flow meter provided in the suction pipeline for measuring the flow rate of the liquid flowing through the suction pipeline. The processor In a suction pressure-flow rate plane showing the relationship between the suction pressure and the flow rate, determine the distance between the coordinates on the suction pressure-flow rate plane formed by the suction pressure and the flow rate in the normal perfusion state of the suction pipeline and the coordinates on the suction pressure-flow rate plane formed by the actual suction pressure and the flow rate. Determine the abnormality of the perfusion state based on whether the distance exceeds a second threshold value. The perfusion state detection device according to claim 11, characterized by the above.

15. It has a pressure gauge provided in the suction pipeline for measuring the suction pressure of the liquid flowing through the suction pipeline. The processor In a suction pressure-drive output plane showing the relationship between the suction pressure and the drive output, determine the distance between the coordinates on the suction pressure-drive output plane formed by the suction pressure and the drive output in the normal perfusion state of the suction pipeline and the coordinates on the suction pressure-drive output plane formed by the actual suction pressure and the drive output. Determine the abnormality of the perfusion state according to whether the distance exceeds a third threshold value The perfusion state detection device according to claim 11, characterized in that

16. The processor is When it is determined that an abnormality has occurred in the perfusion state Reduce the driving output of the water supply pump that flows the liquid through the water supply pipeline The perfusion state detection device according to claim 11, characterized in that

17. An endoscope, A water supply pump that flows a liquid through the water supply pipeline of the endoscope, A suction pump that flows the liquid through the suction pipeline of the endoscope, A flow meter provided in the suction pipeline for measuring the flow rate of the liquid flowing through the suction pipeline, A valve for generating a reverse injection due to a water hammer action in the suction pipeline, A processor, and is provided with The processor is In a plane showing the relationship between any two of the driving output for the suction pump, the flow rate of the liquid flowing through the suction pipeline, and the suction pressure in the suction pipeline, the coordinates on the plane by the two values in the normal perfusion state of the suction pipeline and the coordinates on the actually measured plane, find the distance between them, Detect the abnormality of the perfusion state of the suction pipeline according to whether the distance exceeds a first threshold value, Based on the detection result of the perfusion state, control the opening and closing of the valve to cause the reverse injection in the suction pipeline An endoscope system, characterized in that ​

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