JP2014187999A - Medical expansion and contraction driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized low power consumption medical expansion and contraction driving device.SOLUTION: Secondary piping 14 connected to a balloon 2 is connected to an output port of pressure transmission partition wall means 17, and primary piping 16 is connected to an input port. First branch piping 16a branched from the primary piping is connected to an exhaust port of a pump 15 through a first electromagnetic valve 30, and second branch pipe 16b branched from the primary piping is connected to an intake port of the pump through a second electromagnetic valve 31. Control means 32 executes control so as to repeat an operation to open and close the first electromagnetic valve and the second electromagnetic valve alternately in normal operation, and set the first electromagnetic valve and the second electromagnetic valve to an open state at the starting time (from the start of the operation to a predetermined state of pressure generation means).

Description

  The present invention relates to a medical inflation / deflation drive device that inflates / deflates a driven device such as a balloon catheter for intra-aortic balloon pumping (IABP) by alternately outputting positive pressure and negative pressure, for example.

  For example, in an IABP balloon catheter, the balloon is inserted into an arterial blood vessel near the patient's heart, and inflated and deflated in accordance with the heart beat, thereby performing an adjuvant treatment of the heart. As a driving device for inflating and deflating a balloon, a device as shown in the following Patent Document 1 is known.

  The drive device shown in this publication has a primary side piping system and a secondary side piping system, and these systems are provided by a pressure transmission partition device (generally called a capacity limiting device (VLD) or an isolator). The pressure fluctuation generated in the primary side piping system is isolated and transmitted to the secondary side piping system, and the balloon is inflated and contracted by the pressure change generated in the secondary side piping system. In this way, the primary piping system and the secondary piping system are separated from each other by separating the fluid for driving the balloon and the fluid that is the source of the positive and negative pressures to expand and contract the balloon. This is to improve responsiveness. In addition, by keeping the secondary piping system airtight except for leakage due to diffusion, a large amount of fluid in the relatively expensive secondary piping system is not consumed, that is, pressure is generated at low cost. . As the gas sealed in the secondary piping system, helium gas having a small mass and excellent responsiveness is preferably used.

  In the primary side piping system of such a medical expansion / contraction driving device, the piping on the input side of the pressure transmission partition device is branched, and one branch pipe (positive pressure branch pipe) is used as an exhaust port of the pump. By connecting the branch pipe (negative pressure side branch pipe) to the intake port of the pump and controlling the opening and closing of the solenoid valves installed in each branch pipe, positive pressure and negative pressure are alternately applied to the pressure transmission partition device. Repeat supply. Since the operation is unstable at the start of pump operation (starting up), each solenoid valve is closed, and after the pump is in a predetermined state (stable state), it shifts to normal operation (the balloon Expansion and contraction are started).

International Publication WO2011 / 111479 Pamphlet

  However, according to the prior art, at the start of pump operation, each solenoid valve is closed and is set to a closed state until the pump reaches a predetermined state (stable state). Since the exhaust side piping and the intake side piping are in a sealed state, the load applied to the pump is large, the power consumption of the motor driving the pump is large, and it is necessary to use a battery with a large capacity as the mounted battery. There is a problem that the apparatus becomes larger.

  The present invention has been made in view of the above, and an object of the present invention is to provide a small medical expansion / contraction drive device with low power consumption.

  The medical expansion / contraction drive device according to the present invention includes a pressure transmission partition means connected to an output port of a driven device via a secondary pipe, and a primary pipe connected to an input port of the pressure transmission partition means. A first branch pipe and a second branch pipe branched from the primary pipe, and a pressure at which the first branch pipe is connected to the exhaust port and the second branch pipe is connected to the intake port. Generating means, a first electromagnetic valve interposed in the first branch pipe, a second electromagnetic valve interposed in the second branch pipe, and the driven device so as to repeat expansion and contraction, Control means for controlling the opening and closing of each of the first solenoid valve and the second solenoid valve, the control means until the pressure generating means is in a predetermined state from the start of operation, Set the second solenoid valve to the open state It is characterized in.

  In the medical expansion / contraction drive device according to the present invention, the medical expansion / contraction drive device further includes a third electromagnetic valve that opens the primary pipe to the atmosphere, and the control unit is configured to start the operation until the pressure generation unit reaches a predetermined state from the start of operation. In addition to setting the first solenoid valve and the second solenoid valve to the open state, the third solenoid valve can also be set to the open state.

  According to the present invention, since the first electromagnetic valve and the second electromagnetic valve are set in an open state until the pressure generating means is in a predetermined state from the start of operation, the first branch pipe and the second branch pipe are communicated with each other. The pressure increase in the first branch pipe and the pressure drop in the second branch pipe from the start of operation to the predetermined state are prevented, and the pressure applied to the pressure generation means can be reduced. it can. Accordingly, power consumption can be reduced, and a small battery can be used as the battery to be mounted, so that the apparatus can be downsized.

It is a schematic sectional drawing which shows the balloon catheter of embodiment of this invention. It is the schematic which shows the usage example of the balloon catheter of embodiment of this invention. 1 is a schematic configuration diagram of a medical inflation / deflation drive device according to an embodiment of the present invention. It is sectional drawing which shows the pressure transmission partition apparatus of embodiment of this invention. It is a figure which shows the operation | movement at the time of starting of the medical expansion / contraction drive apparatus of embodiment of this invention. It is a flowchart which shows the control at the time of starting of the medical expansion / contraction drive apparatus of embodiment of this invention. It is a figure which shows operation | movement at the time of normal operation (at the time of balloon expansion | swelling) of the medical expansion / contraction drive apparatus of embodiment of this invention. It is a figure which shows operation | movement at the time of normal operation (at the time of balloon shrinkage | contraction) of the medical expansion / contraction drive apparatus of embodiment of this invention.

  Hereinafter, a medical inflation / deflation drive device according to an embodiment of the present invention will be described in detail with reference to the drawings. The medical inflation / deflation drive device according to the present embodiment is used to inflate and deflate a balloon of an IABP balloon catheter. Prior to description of the medical inflation / deflation drive device according to the present embodiment, first, an IABP balloon catheter will be described with reference to FIG.

  As shown in FIG. 1, an IABP balloon catheter 1 has a balloon 2 that expands (deflates) and contracts in accordance with the pulsation of the heart. The balloon 2 is formed of a cylindrical balloon film having a film thickness of about 50 to 150 μm. In the present embodiment, the shape of the balloon membrane in the expanded state is a cylindrical shape, but is not limited thereto, and may be a polygonal cylindrical shape.

  The balloon 2 for IABP is made of a material having excellent bending fatigue resistance. The outer diameter and length of the balloon 2 are set according to the inner volume of the balloon 2 that greatly influences the assist effect of the cardiac function, the inner diameter of the arterial blood vessel, and the like. The balloon 2 usually has an inner volume of 25 to 50 cc, an outer diameter of 14 to 18 mm when expanded, and a length of 150 to 270 mm.

  The distal end of the balloon 2 is attached to the outer periphery of the distal end of the inner tube 4 through a short tube 3 or directly by heat fusion or adhesion. The proximal end of the balloon 2 is joined to the distal end of the catheter tube 6 via a contrast marker 5 made of a metal tube or the like or directly. Through the first lumen formed inside the catheter tube 6, pressure fluid is introduced into or led out from the balloon 2, so that the balloon 2 is expanded or contracted. The balloon 2 and the catheter tube 6 are joined by heat sealing or adhesion with an adhesive such as an ultraviolet curable resin.

  The distal end of the inner tube 4 protrudes farther than the distal end of the catheter tube 6. The inner tube 4 is inserted in the balloon 2 and the catheter tube 6 in the axial direction. The proximal end of the inner tube 4 is communicated with the second port 8 of the branch portion 7. A second lumen that does not communicate with the first lumen formed inside the balloon 2 and the catheter tube 6 is formed inside the inner tube 4. The inner tube 4 sends blood pressure taken at the open end 9 at the distal end to the second port 8 of the branching section 7 and measures blood pressure fluctuation therefrom.

  When the balloon catheter 1 is inserted into the artery, the second lumen of the inner tube 4 located in the balloon 2 is also used as a guide wire insertion lumen for conveniently inserting the balloon 2 into the artery. When the balloon catheter is inserted into a body cavity such as a blood vessel, the balloon 2 is wound around the outer periphery of the inner tube 4. The inner tube 4 is made of, for example, the same material as the catheter tube 6. The inner diameter of the inner tube 4 may be any diameter that allows the guide wire to be inserted, and is, for example, 0.15 to 1.5 mm, preferably 0.5 to 1 mm. The wall thickness of the inner tube 4 is preferably 0.1 to 0.4 mm. The total length of the inner tube 4 is determined according to the axial length of the balloon catheter 1 inserted into the blood vessel and is not particularly limited, but is, for example, about 500 to 1200 mm, preferably about 700 to 1000 mm.

  The catheter tube 6 is preferably made of a material having a certain degree of flexibility. The inner diameter of the catheter tube 6 is preferably 1.5 to 4.0 mm, and the wall thickness of the catheter tube 6 is preferably 0.05 to 0.4 mm. The length of the catheter tube 6 is preferably about 300 to 800 mm.

  A branch portion 7 installed outside the patient's body is connected to the proximal end of the catheter tube 6. The branch portion 7 is formed separately from the catheter tube 6 and fixed by means such as heat fusion or adhesion. The branch portion 7 includes a first port 10 for introducing or discharging pressure fluid to and from the first lumen in the catheter tube 6 and the balloon 2, and a second port 8 communicating with the second lumen of the inner tube 4. Is formed.

  As shown in FIG. 2, the first port 10 is connected to an inflation / deflation drive device 11, and fluid pressure is supplied by the drive device 11 so that the balloon 2 is inflated or deflated.

  As shown in FIG. 2, the second port 8 is connected to a blood pressure fluctuation measuring device 12, and can measure blood pressure fluctuations in the artery taken from the opening end 9 at the distal end of the balloon 2. Based on the blood pressure fluctuation measured by the blood pressure fluctuation measuring device 12, the driving device 11 is controlled in accordance with the pulsation of the heart 13 shown in FIG. 2, and the balloon 2 is expanded and expanded in a short cycle of 0.4 to 1 second. It is designed to contract.

  The details of the expansion / contraction drive device 11 are shown in FIG. A pressure transmission partition device 17 is provided between the secondary piping system 14 that communicates with the catheter tube 6 of the balloon catheter 1 via the first port 10 and the primary piping system 16 that communicates with the pump 15 as the primary pressure generating means. Is intervening. As shown in FIG. 4, the pressure transmission partition device 17 includes a first chamber 20 and a second chamber 21 that are hermetically partitioned by a diaphragm 18 and a plate 19.

  The first chamber 20 communicates with the primary piping system 16 through a port (input port) 22. The second chamber 21 communicates with the secondary piping system 14 through a port (output port) 23. Although the fluid communication between the first chamber 20 and the second chamber 21 is interrupted, the pressure change (volume change) in the first chamber 20 changes due to the displacement of the diaphragm 18. Change). By adopting such a structure, the pressure fluctuation of the primary piping system 16 can be transmitted to the secondary piping system 14 without causing the primary piping system 16 and the secondary piping system 14 to communicate with each other. Moreover, it is easy to control the volume (chemical equivalent) of the gas sealed in the secondary piping system 14 to be constant.

  In this embodiment, the internal fluid of the primary piping system 16 is air, and the internal fluid of the secondary piping system 14 is helium gas. The reason why the internal fluid of the secondary piping system 14 is helium gas is to increase the response of inflation / deflation of the balloon 2 by using a gas having low viscosity and mass.

  As shown in FIG. 3, the primary piping system 16 is provided with a pump 15 as a primary pressure generating means. The pump 15 is an intake / exhaust pump that generates a positive pressure at the exhaust port (positive pressure output port) and generates a negative pressure at the intake port (negative pressure output port). In the present embodiment, the positive pressure and the negative pressure are generated by the single pump 15, but two pumps, a positive pressure generating pump and a negative pressure generating pump, may be provided. A first pressure tank 25 as a positive pressure tank is connected to the positive pressure output port of the pump 15 via a pressure reducing valve 24. Further, a second pressure tank 27 as a negative pressure tank (vacuum tank) is connected to the negative pressure output port of the pump 15 via a throttle valve 26.

  The first pressure tank 25 and the second pressure tank 27 are equipped with pressure sensors 28 and 29 as pressure detection means for detecting respective internal pressures. A branch pipe 16a branched from the primary pipe of the primary piping system 16 is connected to the first pressure tank 25, and a positive pressure valve (first electromagnetic valve) 30 that is an electromagnetic on-off valve is connected to the branch pipe 16a. It is intervened. A branch pipe 16b branched from the primary pipe of the primary piping system 16 is connected to the second pressure tank 27, and a negative pressure valve (second electromagnetic valve) 31 that is an electromagnetic on-off valve is connected to the branch pipe 16b. It is intervened. Opening and closing of the positive pressure valve 30 and the negative pressure valve 31 is controlled by the control means 32.

  An air release valve (third electromagnetic valve) 36 that is an electromagnetic on-off valve is interposed in the branch pipe 16c branched from the primary pipe of the primary pipe system 16, and the tip of the branch pipe 16c is opened to the atmosphere. ing. The air release valve 36 is provided to release the pressure in the primary piping system 16 (including the branch pipes 16a and 16b) when the pump 15 is started (at the start of operation). Opening and closing of the air release valve 36 is controlled by the control means 32.

  The output port 23 of the pressure transmission partition device 17 shown in FIG. 4 is connected to the secondary piping of the secondary piping system 14 shown in FIG. The secondary piping system 14 communicates with the inside of the balloon 2 via the catheter tube 6 and is a sealed system in which helium gas is sealed. The secondary piping system 14 is configured by a hose or a tube. The secondary piping system 14 is equipped with a pressure sensor 33 as piping system pressure detecting means for detecting the internal pressure. The output of the pressure sensor 33 is input to the control means 32.

  Further, although not shown in the figure, an exhaust pump is connected to the secondary piping system 14 via a solenoid valve. The solenoid valve and the exhaust pump are for evacuating the inside of the piping system 14 in order to replace the inside of the secondary piping system 14 with helium gas before using the balloon catheter. The solenoid valve is closed and the exhaust pump is not driven.

  Further, the secondary piping system 14 is equipped with an electromagnetic valve 34. When the gas pressure in the secondary piping system 14 rises above a predetermined value, the electromagnetic valve 34 opens for a predetermined time, I try to let gas escape. This control is performed by the control means 32. Furthermore, the secondary piping system 14 has a replenishing device (not shown) for replenishing a predetermined amount of helium gas so that the chemical equivalent of the gas inside the secondary piping system 14 is always kept constant. It is connected.

  The control by the control means 32 at the start of operation (starting) of the expansion / contraction drive device 11 will be described with reference to FIGS. When the operation of the expansion / contraction drive device 11 is started, the control means 32 firstly, as shown in FIG. 5, all the valves on the primary piping system 16 side, that is, the positive pressure valve 30 and the negative pressure valve. 31 and the air release valve 36 are set to an open state (step S1). Next, the pump 15 is started, that is, power is supplied from the power supply unit to the drive motor of the pump 15 to start rotation (step S2).

  Thereafter, the control means 32 gradually increases the rotational speed of the drive motor of the pump 15 at a predetermined rate set in advance (step S3). Next, the control means 32 determines whether or not the rotational speed has reached a predetermined target rotational speed set in advance while monitoring the rotational speed of the drive motor of the pump 15 (step S4). If it is determined that it has not reached, the process returns to step S3. If it is determined in step S4 that the target rotational speed has been reached, all valves on the primary piping system 16, that is, the positive pressure valve 30, the negative pressure valve 31, and the atmosphere release valve 36 are set to a closed state (step S4). S5).

  In addition, the value optimized in order to become the lowest power consumption is employ | adopted for the predetermined rate in step S3 from a viewpoint of power consumption, for example, a suitable value is used in the range of 100-1000 rpm / s. As the predetermined target rotational speed in step S4, a value set according to the specification of the pump 15 (including the drive motor) or the like is adopted, and an appropriate value is used in the range of 2000 to 5000 rpm, for example.

  In step S5, after the valves 30, 31, and 36 are set in the closed state, the pressure PT1 in the second pressure tank 27 is set in advance to the first predetermined pressure in which the pressure PT1 in the first pressure tank 25 is set in advance. After the set second predetermined pressure is reached, normal operation is performed (step S6). As an example, the first predetermined pressure is set to an appropriate value in the range of 400 to 1000 mmHg (gauge pressure), and the second predetermined pressure is set to an appropriate value in the range of about −400 to −1000 mmHg (gauge pressure). .

  During normal operation (step S6), as shown in FIG. 7 and FIG. 8, the pressure applied to the input port of the pressure transmission partition device 17 is positively maintained while the air release valve 36 is set to the closed state. The pressure valve 30 and the negative pressure valve 31 are alternately opened and closed to switch to the pressure of the first pressure tank 25 and the second pressure tank 27. The timing of this switching is controlled by the control means 32 based on the measurement result by the blood pressure fluctuation measuring device of FIG.

  According to the above-described embodiment, the positive pressure valve 30 and the negative pressure valve 31 are set to the open state and the drive motor of the pump 15 is started. Since the valve 31 is left open as it is, the resistance at the time of starting becomes smaller and the driving motor of the pump 15 is reduced as compared with the conventional technique in which both the positive pressure valve and the negative pressure valve are set in the closed state. It is possible to reduce the load applied to the. Therefore, since power consumption can be reduced, it is economical, and a smaller battery (storage battery) can be used as a battery (storage battery) mounted for driving the drive motor of the pump 15. Can be achieved. In addition, as the drive motor and the power supply unit for supplying electric power to the drive motor, it is possible to adopt a lower power unit, and this also makes it possible to reduce the size of the apparatus.

  In the above-described embodiment, the atmosphere release valve 36 and the branch pipe 16c are additionally provided, and in addition to setting the positive pressure valve 30 and the negative pressure valve 31 to the open state at the start, the atmosphere release valve Since 36 is also set in the open state, the load can be further reduced and the power consumption can be more effectively suppressed. That is, when the circuit constituted by the pump 15, the positive pressure tank 25, the positive pressure valve 30, the negative pressure valve 31, the negative pressure tank 27, and the pipes (16, 16a, 16b) connecting them is a closed circuit, In some cases, the residual pressure in the previous operation may remain in the circuit. In this case, the residual pressure becomes a load (resistance) at the time of starting, but the air release valve 36 is also opened. As a result, the residual pressure is released, and the load applied when the drive motor of the pump 15 is started can be further reduced. However, even if the circuit is a closed circuit (that is, the atmosphere release valve 36 is closed), the positive pressure valve 30 and the negative pressure valve 31 are set to the open state to reduce the load accordingly. Since the effect can be realized, the atmosphere release valve 36 and the branch pipe 16c may be omitted.

  Furthermore, in the above-described embodiment, since the rotational speed until the target rotational speed of the drive motor of the pump 15 at the time of starting is gradually increased at a predetermined rate, compared with the conventional technique that has been increased at a stroke. , Power consumption can be further reduced.

  In the embodiment described above, a balloon catheter is used as the driven device. However, the expansion / contraction drive device according to the present invention is used for driving other medical devices as long as the medical device repeats expansion and contraction. You can also.

  The embodiment described above is described for facilitating the understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the embodiment described above is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Balloon catheter 2 ... Balloon 14 ... Secondary piping system 15 ... Pump 16 ... Primary piping system 16a, 16b, 16c ... Branch pipe 17 ... Pressure transmission partition apparatus 25 ... 1st pressure tank (positive pressure tank)
27 ... Second pressure tank (negative pressure tank)
30 ... Positive pressure valve 31 ... Negative pressure valve 32 ... Control means 36 ... Air release valve

Claims (2)

Pressure-transmitting partition means in which the driven device is connected to its output port via a secondary pipe;
A primary pipe connected to the input port of the pressure transmitting partition means;
A first branch pipe and a second branch pipe branched from the primary pipe,
Pressure generating means in which the first branch pipe is connected to the exhaust port, and the second branch pipe is connected to the intake port;
A first solenoid valve interposed in the first branch pipe;
A second solenoid valve interposed in the second branch pipe;
Control means for controlling the opening and closing of the first solenoid valve and the second solenoid valve so that the driven device repeats expansion and contraction;
The control means sets the first electromagnetic valve and the second electromagnetic valve in an open state until the pressure generating means is in a predetermined state from the start of operation, the medical expansion / contraction drive device characterized by . A third solenoid valve for opening the primary pipe to the atmosphere;
The control means includes the third solenoid valve in addition to setting the first solenoid valve and the second solenoid valve to the open state until the pressure generating means is in a predetermined state from the start of operation. The medical expansion / contraction drive device according to claim 1, wherein the medical expansion / contraction drive device is set to an open state.

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