JP6932969B2 - Drive device for balloon catheter for IABP - Google Patents

Description

The present invention relates to a balloon catheter driving device used for IABP (intra-aortic balloon pumping).

As a treatment for cardiac dysfunction, IABP (intra-aortic balloon pumping) is performed in which a balloon catheter is inserted into the aorta and the balloon is inflated and contracted in accordance with the heartbeat to assist the cardiac function. The IABP balloon catheter used for IABP (see, for example, Patent Document 1) is inserted from the femoral artery or the like and is used in a state where the balloon is placed in the descending thoracic artery.

By the way, in order to sufficiently obtain the auxiliary effect of cardiac function, the diameter at the time of maximum expansion of the balloon is preferably about 90 to 95% of the diameter of the blood vessel, but the diameter of the blood vessel in which the balloon is placed (inner diameter of the blood vessel). ) Varies from patient to patient. Therefore, prior to the implementation of IABP, the blood vessel diameter is measured using various inspection devices such as IVUS, CT, MRI, and echocardiography, and a catheter equipped with a balloon of the optimum size (diameter) is selected and used. .. Further, as a technique for measuring the blood vessel diameter, as described in Patent Document 2, a balloon catheter has been proposed in which the blood vessel diameter is obtained from the relationship between the pressure of the balloon and the change in volume. .. However, it takes a certain amount of time to measure the blood vessel diameter using these inspection devices and techniques.

Here, IABP may be performed in an emergency such as resuscitation from cardiopulmonary arrest, and if there is not enough time to measure the blood vessel diameter, the size is estimated from the patient's physique (height, etc.). The reality is that there is no choice but to roughly select and use from a plurality of types (for example, about 3 types) of catheters having different (diameters).

However, depending on the patient, the physique may not correlate with the blood vessel diameter, or an appropriate size may not exist as an existing product, and it may not always be possible to sufficiently obtain an auxiliary effect on cardiac function. In particular, using a balloon with a large maximum expansion diameter with respect to the patient's blood vessel diameter means that the balloon that repeatedly expands and contracts repeatedly contacts the blood vessel wall (inner wall of the blood vessel) and presses the blood vessel wall from the inside. Therefore, it is preferable to avoid it as much as possible.

Japanese Unexamined Patent Publication No. 2016-189921 Special Table 2016-528965

The present invention has been made in view of such an actual situation, and an object of the present invention is that it is not necessary to select the balloon size by measuring or estimating the blood vessel diameter of the patient in advance, and the balloon regardless of the size of the blood vessel diameter of the patient. Is to provide a driving device capable of driving a balloon catheter for IABP within a range that does not press the blood vessel from the inside.

The driving device for the balloon catheter for IABP according to the present invention is
A driving device for an IABP balloon catheter having a catheter tube inserted into a patient's blood vessel and a balloon provided at the distal end of the catheter tube.
A pressure generating means for generating pressure to inflate and contract the balloon, and
A pressure detecting means for detecting the internal pressure of the balloon and
A timing control means for controlling the timing of expansion and contraction of the balloon by the pressure generating means according to the heartbeat of the patient during the main operation to assist the patient's cardiac function.
Prior to the main operation, pressure is generated in the pressure generating means so that the balloon expands from the contracted state, and the balloon is connected to the blood vessel based on the change in the internal pressure of the balloon detected by the pressure detecting means. A blood vessel contact pressure derivation means for deriving a blood vessel contact pressure, which is a pressure estimated to be in contact with the inner wall,
It has a maximum pressure setting means for setting a pressure smaller than the blood vessel contact pressure derived by the blood vessel contact pressure deriving means as the maximum pressure generated by the pressure generating means during the main operation.

In the driving device for the balloon catheter for IABP according to the present invention, prior to the main operation, the blood vessel contact pressure, which is the pressure at which the balloon is presumed to have contacted the inner wall of the blood vessel, is derived. The balloon is inflated and contracted as the maximum pressure generated by the pressure generating means at a pressure smaller than the pressure. Therefore, during the main operation, when the balloon is inflated, the diameter of the balloon does not reach the blood vessel diameter, and the balloon does not press the blood vessel from the inside regardless of the size of the blood vessel diameter of the patient. The balloon can be inflated and contracted. Therefore, it is not necessary to measure the blood vessel diameter of the patient in advance, and it is possible to respond quickly even in an emergency. Further, it is possible to eliminate the need to prepare a plurality of types of catheters according to the blood vessel diameter of the patient and the work of selecting the optimum catheter from these.

In the driving device for the balloon catheter for IABP according to the present invention, the blood vessel contact pressure deriving means is when the amount of change in the internal pressure of the balloon detected by the pressure detecting means exceeds a preset predetermined threshold. The pressure generated by the pressure generating means can be used as the blood vessel contact pressure. In the state where no external force acts on the balloon, the internal pressure of the balloon increases substantially in proportion to the pressure generated by the pressure generating means, but when the outer circumference of the balloon abuts on the blood vessel wall (that is, the balloon diameter becomes the blood vessel diameter). (When it reaches), the blood vessel wall suppresses further expansion, and the internal pressure of the balloon changes and rises relatively rapidly. Therefore, it can be estimated that the time when the amount of change in the internal pressure of the balloon exceeds a threshold value set appropriately in advance is the time when the balloon abuts on the blood vessel wall and presses the blood vessel wall from the inside. Can be the blood vessel contact pressure.

In the driving device for the balloon catheter for IABP according to the present invention, the maximum pressure setting means can set the maximum pressure in the range of 80 to 95% of the blood vessel contact pressure. By setting the maximum pressure in this range, the balloon can be inflated with the largest possible diameter within the range where the balloon does not press the vessel wall from the inside, and the maximum or nearly acceptable heart depending on the patient's vessel diameter. The effect of functional assistance can be obtained.

In the driving device for the balloon catheter for IABP according to the present invention, the relationship between the internal pressure of the balloon and the diameter of the balloon is obtained in advance, and the amount of change in the internal pressure of the balloon detected by the pressure detecting means is preset. Further, it is possible to have a blood vessel diameter deriving means for deriving the diameter corresponding to the internal pressure at the time when the predetermined threshold is exceeded as the blood vessel diameter of the patient. With this configuration, the blood vessel diameter of the patient can be easily known without using a separate measuring device or the like.

FIG. 1 is a cross-sectional view of a balloon catheter for IABP driven by an IABP driving device according to an embodiment of the present invention. FIG. 2 is a block diagram showing a configuration of a main part of an IABP drive device according to an embodiment of the present invention. FIG. 3 is a diagram showing an example of the relationship between the balloon internal pressure and the applied pressure (pressure generated by the pressure generator) in a state where there is no load. FIG. 4 is a diagram showing an example of the relationship between the internal pressure of a balloon placed in a lumen simulating a blood vessel and the applied pressure (pressure generated by a pressure delivery device).

Hereinafter, the driving device (IABP driving device) for the balloon catheter for IABP according to the embodiment of the present invention will be described in detail with reference to the drawings. This IABP drive device is used to inflate and deflate the balloon of an IABP balloon catheter. First, a balloon catheter for IABP as a driving target of the IABP driving device will be described with reference to FIG.

The IABP balloon catheter 21 is a balloon catheter used for intra-aortic balloon pumping (IABP), and has a balloon 22 that expands (expands) and contracts in accordance with the beating of the heart. The balloon 22 is composed of a substantially cylindrical (may be polygonal) thin film (balloon film) having a film thickness of about 50 to 150 μm. The material of the thin film is preferably a material having excellent bending fatigue resistance, and for example, polyurethane or the like can be used. In the present embodiment, the balloon 22 is made of a non-stretchable material, but may be made of a stretchable material.

The outer diameter of the balloon 22 can be determined based on the statistical data of the diameter of the aorta (descending aorta of the chest) of the human body at the time of expansion. Set to a value larger than the blood vessel diameter of a person who is relatively large in. Specifically, the outer diameter of the balloon 22 when inflated can be about 20 to 35 mm. The axial length of the balloon 22 is preferably about 150 to 250 mm, and the internal volume is preferably about 25 to 100 cc.

The distal end 22a of the balloon 22 is attached to the outer periphery of the tip tip 23 by heat fusion or adhesion. The tip tip portion 23 is composed of a substantially cylindrical member, and the distal end portion of the inner tube 24 constituting the catheter tube enters the proximal end side of the lumen 23a, and the lumen 24a and the tip of the inner tube 24 enter. In a state where the lumen 23a of the chip 23 is communicated with each other, they are connected and fixed to each other by heat fusion or adhesion. A blood pressure sensor 29 for measuring blood pressure is attached to the tip tip 23.

The proximal end 22b of the balloon 22 is connected to the outer periphery of the distal end of the outer tube 26 that constitutes the catheter tube, either via or directly through a contrast marker 25 made of a metal tube or the like. The inner pipe 24 is inserted into the outer pipe 26, and the pressure fluid can be introduced or derived into the balloon 22 through the pressure fluid conduction path 26a separated by the inner surface of the outer pipe 26 and the outer surface of the inner pipe 24. This is done so that the balloon 22 expands or contracts. The balloon 22 and the outer tube 26 are joined by heat fusion or adhesion.

The inner tube 24 is arranged so that its distal end side projects toward the distal end side of the outer tube 26 and extends. The lumen 24a of the inner pipe 24 does not communicate with the pressure fluid conduction path 26a. The lumen 24a of the inner tube 24 is used as a lumen through which a guide wire (not shown) to be inserted in advance is inserted when the balloon catheter 21 is inserted into an artery.

When the balloon catheter 21 is inserted into the blood vessel, the balloon 22 is folded and wound around the outer circumference of the portion of the inner tube 24 protruding from the outer tube 26. The inner diameter of the inner pipe 24 may be any diameter as long as the guide wire can 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 24 is preferably 0.1 to 0.4 mm. The total length of the inner tube 24 is determined according to the axial length of the balloon catheter 21 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 outer diameter of the inner tube 24 is about 0.5 to 1.5 mm, preferably 30 to 60% of the inner diameter of the outer tube 26. The outer diameter of the inner pipe 24 is substantially the same along the axial direction. The inner tube 24 is made of, for example, a synthetic resin tube such as polyurethane, polyvinyl chloride, polyethylene, nylon, or polyetheretherketone (PEEK), a nickel-titanium alloy thin tube, a stainless steel thin tube, or the like.

The outer tube 26 is made of a synthetic resin such as polyurethane, polyvinyl chloride, polyethylene terephthalate, and polyamide. The inner diameter of the outer tube 26 is about 1.5 to 4.0 mm, and the wall thickness is about 0.05 to 0.4 mm. The length of the outer tube 26 is about 300 to 800 mm.

A bifurcation 27 installed outside the patient's body is provided at the proximal end of the catheter tube (inner tube 24, outer tube 26). The branch portion 27 is formed separately from the outer pipe 26, and is connected to the outer pipe 26 by heat fusion or adhesion. The branch portion 27 is formed with a first port 27a communicating with the lumen 24a in the inner pipe 24 and a second port 27b communicating with the pressure fluid conduction path 26a in the outer pipe 26.

As shown in FIG. 2, the second port 27b is detachably connected to the other end of the connection tube 11a to which one end is connected to the output port of the pressure generator 12 of the IABP drive device 11, and the second port 27b is detachably connected by the IABP drive device 11. Fluid pressure is supplied so that the balloon 22 expands or contracts. The pressure fluid is not particularly limited, but helium gas having a small viscosity and a small mass can be used so that the balloon 22 expands and contracts quickly in response to the driving of the IABP driving device 11.

In addition to the first port 27a and the second port 27b, the branch portion 27 is formed with a third port 27c. The proximal end side of the optical fiber 28 is drawn out from the third port 27c. An optical connector 28a is connected to the proximal end of the optical fiber 28. A blood pressure sensor 29 attached to a tip 23 for measuring blood pressure is connected to the distal end of the optical fiber 28. As shown in FIG. 2, the optical connector 28a is detachably connected to a connection connector 11b provided at the other end of the connection optical fiber to which one end thereof is connected to the blood pressure fluctuation measuring device 14 of the IABP drive device 11. Based on the fluctuation of blood pressure measured by the blood pressure fluctuation measuring device 14, the balloon 22 is inflated and contracted in a short cycle of 0.4 to 1 second.

Next, the IABP driving device 11 to which the present invention is applied for driving the above-mentioned IABP balloon catheter 21 will be described with reference to FIG. The IABP driving device 11 includes a pressure generating device (pressure generating means) 12, a pressure detecting device (pressure detecting means) 13, a blood pressure fluctuation measuring device 14, and a control device 15. Although not shown, the IABP drive device 11 is also provided with an input device for performing various settings and data input, a display device (monitor) for displaying various data, an operating status, and the like. ing.

The pressure generator 12 is a device that generates pressure for expanding and contracting the balloon 22, a primary piping system having a pump or the like for generating pressure, and a pressure fluid such as helium gas for expanding the balloon 22. It has a secondary piping system having a supply tank and the like, and a pressure transmission partition wall device (isolator) interposed between the primary piping system and the secondary piping system. The output port of the pressure generator 12 is connected to the second port 27b via the connecting tube 11a.

The pressure generator 12 controls the primary piping system, and the balloon 22 fills the pressure fluid conduction path 26a of the catheter 21 connected to the secondary piping system via the second port 27b. By pushing it to the side, the balloon 22 is inflated, and conversely, by drawing in the pressure fluid, the balloon 22 is contracted. The maximum pressure generated by the pressure generator 12 is adjusted according to a set value that can be arbitrarily changed and adjusted. The pressure generator 12 is controlled by a timing control unit 15a described later, and inflates and contracts the balloon 22 in response to the beating of the heart.

The pressure detection device 13 has a pressure sensor 13a provided in the output port of the pressure generator 12, and detects the internal pressure of the balloon 22 based on the detection signal from the pressure sensor 13a. The blood pressure fluctuation measuring device 14 detects (measures) blood pressure fluctuations based on an optical signal (blood pressure signal) sent from the optical fiber 28, the optical connector 28a, the optical connector 11b, and the blood pressure sensor 29 sent via the connecting optical fiber. It is a device to do.

Although not shown, the control device 15 is a device including a microprocessor and a storage device, and realizes a desired function according to a control program and data stored in the storage device. The control device 15 includes a timing control unit (timing control means) 15a, a blood vessel contact pressure derivation unit (blood vessel contact pressure derivation means) 15b, and a maximum pressure setting unit (maximum pressure setting means) 15c as a plurality of functional components. I have. Although not essential, the control device 15 may further include a blood vessel diameter deriving unit (blood vessel diameter deriving means) 15d.

The timing control unit 15a determines the expansion and contraction of the balloon 22 by the pressure generator 12 according to the patient's heartbeat, that is, the blood pressure fluctuation measured by the blood pressure fluctuation measuring device 14, during the main operation that assists the patient's cardiac function. Control the timing.

The blood vessel contact pressure leading-out unit 15b and the maximum pressure setting unit 15c determine the maximum pressure generated by the pressure generator 12 during the main operation prior to the main operation. That is, the blood vessel contact pressure deriving unit 15b generates pressure in the pressure generating device 12 so that the balloon 22 expands to the maximum diameter from the contracted state of the balloon 22, and the internal pressure of the balloon 22 detected by the pressure detecting device 13 Based on the change in, the blood vessel contact pressure, which is the pressure value at which the outer circumference of the balloon 22 is estimated to have touched the blood vessel wall of the patient, is derived.

More specifically, the blood vessel contact pressure derivation unit 15b applies the pressure at the time when the amount of change in the internal pressure of the balloon 22 detected by the pressure detection device 13 exceeds a preset predetermined threshold value. Pressure. Here, in a state where the external pressure (external force) does not act on the balloon 22, the internal pressure of the balloon 22 is generated by the pressure generator 12 as shown in FIG. 3, for example, in the range where the maximum diameter of the balloon 22 is not reached. It increases uniformly in substantially proportion to the increase in the applied pressure (applied pressure).

When there is some restriction on the expansion of the balloon 22, that is, the outer diameter of the balloon 22 placed in the lumen expands to the inner diameter of the lumen, and the outer circumference of the balloon 22 expands the inner wall of the lumen from the inside. When the balloon comes into contact with pressure, the inner wall restricts further free expansion of the balloon 22, so that the internal pressure of the balloon 22 suddenly rises and changes as shown in FIG. Therefore, the amount of change in the internal pressure of the balloon 22 is compared with a predetermined threshold value set in advance, and the time when the internal pressure of the balloon 22 suddenly rises and changes and exceeds the threshold value (displayed as a contact point in the figure) , It can be estimated that the outer circumference of the balloon 22 abuts on the inner wall of the lumen. The applied pressure Po at this time is defined as the blood vessel contact pressure.

In the state where the balloon 22 is placed in the blood vessel of the living body, unlike the static state as described above, the external pressure received by the balloon 22 fluctuates due to the fluctuation of the blood pressure accompanying the heartbeat, so that the internal pressure of the balloon 22 is changed. However, since the fluctuation of blood pressure associated with the heartbeat is known (it can be measured by the blood pressure fluctuation measuring device 14), the influence of such fluctuation of blood pressure can be eliminated.

The maximum pressure setting unit 15c sets a pressure smaller than the blood vessel contact pressure derived by the blood vessel contact pressure lead-out unit 15b as the maximum pressure generated by the pressure generator 12 during the main operation. By setting the maximum pressure generated by the pressure generator 12 during the main operation to a value smaller than the blood vessel contact pressure, the balloon 22 expands to the blood vessel diameter even when the balloon 22 expands to the maximum according to the maximum pressure. There is nothing to do. Therefore, it is possible to suppress the outer circumference of the balloon 22 from coming into contact with the blood vessel wall, and it is possible to reduce the harmful effects of the balloon 22 repeatedly coming into contact with the blood vessel wall so as to press the blood vessel wall from the inside.

More specifically, the maximum pressure setting unit 15c sets the diameter of the balloon 22 to the maximum diameter according to the maximum pressure in order to sufficiently obtain the auxiliary effect of the cardiac function for the maximum pressure to be generated by the pressure generator 12. It is preferable to set the diameter in the range of 80 to 95% of the blood vessel contact pressure so that the diameter when expanded to about 90 to 95% of the blood vessel diameter.

Although it is not always necessary to provide the blood vessel diameter deriving unit 15d, an additional blood vessel diameter deriving unit 15d can be provided. The blood vessel diameter deriving unit 15d obtained the relationship between the internal pressure of the balloon 22 and the diameter of the balloon 22 in advance, stored this relationship in advance in the storage device included in the control device 15, and detected it by the pressure detecting device 13. The diameter corresponding to the internal pressure at the time when the amount of change in the internal pressure of the balloon 22 exceeds a preset predetermined threshold is derived as the blood vessel diameter of the patient. The obtained blood vessel diameter can be displayed on a display device attached to the drive device 11. Healthcare professionals can use the displayed vessel diameter as a reference for IABP-related procedures and other procedures.

In the IABP drive device 11 according to the present embodiment, prior to the main operation, the blood vessel contact pressure estimated that the balloon 22 has contacted the blood vessel wall of the patient is derived, and during the main operation, the blood vessel contact pressure is higher than the blood vessel contact pressure. The balloon 22 is inflated and contracted with a small pressure as the maximum pressure. Therefore, during the main operation, when the balloon 22 is inflated, the diameter of the balloon 22 does not reach the diameter of the blood vessel of the patient, and the balloon 22 touches the blood vessel wall regardless of the diameter of the blood vessel of the patient. It can be driven with a balloon diameter that does not come into contact with the blood vessel wall so as to press from the inside. Therefore, it is possible to assist the cardiac function in the optimum state without measuring the blood vessel diameter of the patient in advance, and it is possible to respond quickly even in an emergency. Further, it is not necessary to prepare a plurality of types of catheters according to the blood vessel diameter of the patient, and the work of selecting the optimum catheter from these can be omitted.

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

11 ... IABP drive device (drive device for balloon catheter for IABP)
12 ... Pressure generator (pressure generating means)
13 ... Pressure detection device (pressure detection means)
14 ... Blood pressure fluctuation measuring device 15 ... Control device 15a ... Timing control unit (timing control means)
15b ... Blood vessel contact pressure derivation unit (blood vessel contact pressure derivation means)
15c ... Maximum pressure setting unit (maximum pressure setting means)
21 ... Balloon catheter for IABP 22 ... Balloon 24 ... Inner tube 26 ... Outer tube 27 ... Branch 27a ... First port 27b ... Second port 28 ... Optical fiber 28a ... Optical connector 29 ... Blood pressure sensor

Claims (4)

A driving device for an IABP balloon catheter having a catheter tube inserted into a patient's blood vessel and a balloon provided at the distal end of the catheter tube.
A pressure generating means for generating pressure to inflate and contract the balloon, and
A pressure detecting means for detecting the internal pressure of the balloon and
A timing control means for controlling the timing of expansion and contraction of the balloon by the pressure generating means according to the heartbeat of the patient during the main operation to assist the patient's cardiac function.
Prior to the main operation, pressure is generated in the pressure generating means so that the balloon expands from the contracted state, and the balloon is connected to the blood vessel based on the change in the internal pressure of the balloon detected by the pressure detecting means. A blood vessel contact pressure derivation means for deriving a blood vessel contact pressure, which is a pressure estimated to be in contact with the inner wall,
A balloon catheter for IABP having a maximum pressure setting means for setting a pressure smaller than the blood vessel contact pressure derived by the blood vessel contact pressure deriving means as the maximum pressure generated by the pressure generating means during the main operation. Drive device. The blood vessel contact pressure deriving means is a pressure generated by the pressure generating means when the amount of change in the internal pressure of the balloon detected by the pressure detecting means with respect to the applied pressure exceeds a preset predetermined threshold. The driving device for the balloon catheter for IABP according to claim 1, wherein the pressure is the blood vessel contact pressure. The driving device for a balloon catheter for IABP according to claim 1 or 2, wherein the maximum pressure setting means sets the maximum pressure in the range of 80 to 95% of the blood vessel contact pressure. The relationship between the internal pressure of the balloon and the diameter of the balloon is obtained in advance, and the change amount of the internal pressure of the balloon detected by the pressure detecting means with respect to the applied pressure exceeds a predetermined threshold value set in advance. The driving device for a balloon catheter for IABP according to any one of claims 1 to 3, further comprising a blood vessel diameter deriving means for deriving a diameter corresponding to the internal pressure as a blood vessel diameter of a patient.

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