JPH07231934A - Cannula and auxiliary circulator - Google Patents

Abstract

PURPOSE:To enable assistance in flow rate and in pulsational pressure simultaneously with one cannula in an endermic circulation assistance. CONSTITUTION:A pump chamber 16 of a blood pump 12 is isolated into a liquid chamber 20 and an air chamber 22 with a partition 18. A tube 28 of a cannula 14 is connected to an out/inflow port 26 of the liquid chamber 20. A tip member 34 having a conical part 30 with a suction port 38 is mounted at the tip of the tube 28 and a suction valve 40 is mounted in the conical part 30. A discharge valve 60 is mounted on the tube 28 surrounding discharge ports 52 and 54. When the blood pump 12 is operated, the blood is sucked at the suction port 38 and discharged from the discharge ports 52 and 54. When the suction port 38 is placed in a left ventricle B and the discharge ports 52 and 54 are placed in an aorta C, assistance in flow rate and in pulsational pressure are realized simultaneously.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cannula which is inserted into the left ventricle or the aorta and is used for auxiliary circulation of blood flow by inhaling blood from the left ventricle side and discharging the blood to the aorta side. The present invention relates to an attached auxiliary circulation device.

[0002]

BACKGROUND ART As is well known, treatment such as drug administration and oxygen inhalation for chronic heart failure such as valvular disease, acute myocardial infarction, and progressive and irreversible heart failure such as cardiogenic shock after open heart surgery. In addition, treatment with mechanical assisted circulation may be performed.

As a kind of this mechanical assisted circulation, percutaneous assisted circulation is known in which pressure assistance and flow rate assistance are performed via a catheter or the like inserted into a blood vessel. For percutaneous assisted circulation,
For example, aortic balloon pumping (IABP) that performs pressure assistance by expanding and contracting the balloon in the aorta, or a route that inhales from the vein side and bypasses the heart to the arterial side, and a pump installed in this route Percutaneous cardiopulmonary bypass (PCPS), which assists in flow, has been employed.

[0004]

However, the IAB
P is only pulsatile pressure assistance, not flow rate assistance, PCPS
In that case, the flow rate could be assisted by a constant flow rate, but the pulsatile pressure assistance was not possible. Further, for example, it is possible to use IABP and PCPS together to perform pressure assistance and flow rate assistance at the same time, but there are only a limited number of blood vessels through which catheters and the like used therein can be inserted, and IABP and PCPS can be used together. Since other percutaneous treatment cannot be performed when used in combination, the above-described combination is difficult from this point of view.

[0005]

As a means for solving the above-mentioned problems, a cannula according to claim 1 is formed in a side wall with an inlet opening at one end and a side wall keeping a set distance from the inlet. A flexible tube having a discharge port and an inside of the tube with respect to the suction port, allowing fluid to flow from the suction port into the tube, and from the tube to the suction port. And a flexible membrane suction valve that blocks the outflow of the fluid, and is installed to cover the discharge port on the outer peripheral side of the tube to allow the fluid to flow from the inside of the tube to the discharge port and from the discharge port. And a discharge valve in the form of a flexible film that prevents the fluid from flowing into the tube.

Next, the cannula according to claim 2 is characterized in that, in the cannula according to claim 1, the discharge valve is tubular. Next, the cannula according to claim 3 is the cannula according to claim 1 or 2, wherein the suction valve has a substantially truncated cone shape, and the suction port is provided on the side surface with a substantially conical or substantially truncated cone shape. It is characterized in that a conical portion having a substantially conical valve seat that matches the suction valve on the inner surface is provided at one end of the tube.

Next, the cannula according to claim 4 is characterized in that, in the cannula according to claim 3, the total opening area of the suction port exceeds the radial cross-sectional area of the tube. The auxiliary circulation device according to claim 5 includes the cannula according to any one of claims 1 to 4, an outflow inlet communicating with the other end of the tube of the cannula, and a liquid chamber communicating with the inflow outlet. A pump for sucking fluid from the cannula via the outflow inlet and discharging the fluid to the cannula via the outflow inlet by changing the inner volume of the liquid chamber. .

[0008]

In the cannula according to claim 1 having the above-mentioned structure, for example, a tube is inserted from the right subclavian artery with the suction port side as the leading end, and the suction port is located on the left ventricle side and the discharge port is located on the aortic side with the aortic valve interposed. Position it. Note that the other end of the tube (the end on the proximal side) is left outside the body, and after the air inside the cannula has been evacuated, a piston that reciprocates in the cylinder, for example, is provided with a piston that inhales and discharges from a single inflow / outflow port. Connect to the entrance.

When the pump is in the suction stroke, the inside of the tube is in a relatively negative pressure state, so that the suction valve is opened and blood in the left ventricle flows into the tube through the suction port. On the other hand, when the pump is in the discharge stroke, the inside of the tube is in a relatively positive pressure state, so that the discharge valve is opened and blood in the tube flows out to the aorta. Further, at this time, the discharge pressure of the pump is transmitted to the blood on the aorta side via the blood in the tube to increase the blood pressure in the aorta.

As described above, the blood flow from the left ventricle to the aorta is generated in response to the inhalation / discharge of the pump, and the flow rate can be assisted. Moreover, since the pressure in the tube is alternately switched from negative pressure to positive pressure and from positive pressure to negative pressure in accordance with the suction / discharge stroke of the pump, pulsatile pressure support can be performed.

If the blood pump is operated in accordance with the pulsation of the heart so that the blood pump inhales when the left ventricle contracts and discharges when the left ventricle expands, blood in the left ventricle is inhaled when the left ventricle contracts. The burden on the heart is reduced, and the blood supplied to the aorta is increased when the left ventricle is expanded, and at the same time, the blood pressure in the aorta is increased. Since the left ventricle and the aorta are blocked by the aortic valve during dilation of the left ventricle, the blood discharged from the cannula into the aorta does not flow into the left ventricle.

Therefore, flow rate assistance and pulsatile pressure assistance can be realized without increasing the burden on the heart. Furthermore, since blood flow and pulsation can be secured as described above even in a cardiac arrest state, it is extremely effective as an auxiliary circulation during cardiac arrest.

Next, the cannula according to claim 2 exhibits the same effect as the configuration according to claim 1 described above, and since the discharge valve is tubular, it is easy to adhere to the outer circumference of the tube, and the tube is There is little resistance when inserting and removing. Next, the cannula according to claim 3 exhibits the same effect as the configuration according to claim 1 or 2, and since the conical portion is provided at the tip of the tube, the resistance during insertion is further reduced. Become.

Next, the cannula according to claim 4 exhibits the same effects as those of the above-mentioned configurations according to claims 1 to 3, and the total opening area of the suction ports exceeds the radial cross-sectional area of the tube. Therefore, the inhalation resistance is reduced and the inhalation amount can be increased. Further, the auxiliary circulation device according to claim 5 comprises the cannula according to any one of claims 1 to 4, and the pump for sucking fluid from the cannula and discharging the fluid to the cannula. Therefore, the cannula according to claim 1 The auxiliary circulation described above can be performed, and the same effects as described for the cannula according to claim 1 can be exhibited.

[0015]

EXAMPLES Next, examples of the present invention will be described. As shown in FIG. 1, the auxiliary circulation device 10 of this embodiment includes a blood pump 12 and a cannula 14. Although not shown, the cannula 14 is provided with a well-known side tube.

The blood pump 12 is in the shape of a hollow box and has a pump chamber 16 inside. The interior of the pump chamber 16 is formed by a flexible film-shaped partition wall 18 which can be deformed, so
Is isolated from. However, the liquid chamber 20 and the air chamber 22
The volume of V fluctuates according to the deformation of the partition wall 18. Air chamber 22
An air supply / exhaust nozzle 24 is communicated with the air supply / exhaust nozzle 24, and gas can be supplied to the air chamber 22 via the air supply / exhaust nozzle 24 and discharged from the air chamber 22. On the other hand, an outflow port 26 communicates with the liquid chamber 20, and one end of a tube 28 of the cannula 14 is connected to the outflow port 26.

The tube 28 is made of flexible synthetic resin and is bendable. At the tip of the tube 28, a shell-shaped tip member 34 including a conical portion 30 having a substantially conical shape and a straight pipe portion 32 is attached. As shown in FIGS. 1 and 2, the distal end member 34 has an internal hole 3 communicating with the tube 28.
6 is provided, and the conical portion 30 is provided with four suction ports 38 communicating with the inner hole 36. The total opening area of the four suction ports 38 is set to be larger than the radial cross-sectional area of the tube 28. In the conical portion 30, there is mounted a flexible membrane-shaped, frustoconical suction valve 40 made of segmented polyurethane.

As shown in FIG. 2, the intake valve 40 engages a protrusion 44 provided on the top portion 42 with an engagement hole 46 of the conical portion 30, and further adheres to the cone portion 30 at the protrusion 44 and the top portion 42. ing. On the other hand, the side surface portion 48 of the intake valve 40
Is not fixed except the connecting portion with the top portion 42, and can be freely deformed and displaced.

A curved valve seat 50 is formed on the inner surface of the conical portion 30 so as to match the outer shape of the side surface portion 48 of the suction valve 40. As shown in FIG. Seat 50
And can be close to each other. In addition, the side surface 4
When the valve seat 8 and the valve seat 50 are in close contact with each other, the inside of the suction port 38 is completely shielded.

As shown in FIGS. 1 and 3, the tube 2
In FIG. 8, four discharge ports 52 are provided along the circumferential direction at a distance of about 11 cm from the tip, and similar discharge ports 54 are also provided along the circumferential direction in parallel with these discharge ports 52. It is set up. Further, on the outer periphery of the tube 28, a cylindrical base portion 56 and a tapered tubular taper portion 5 connected to the base portion 56.
A discharge valve 60 having a base portion 56 is attached to the outer circumference of the tube. Similar to the suction valve 40, the discharge valve 60 has a flexible film shape made of segmented polyurethane, and the taper portion 58 can be deformed and displaced. The taper portion 58 has a length capable of covering the discharge ports 52 and 54, and when pressed from the outer surface side to the inner surface side, it is deformed to the inner surface side and comes into close contact with the outer periphery of the tube 28 and is discharged. Exit 52, 54
Can be shielded.

As shown in FIG. 4, this auxiliary circulation device 10
Drives the air supply / exhaust nozzle 24 of the blood pump 12 by a driving device 70.
Used by connecting to. The drive device 70 has a pump (not shown) built therein, and can supply pressurized air to the air chamber 22 by this pump and can suck air in the air chamber 22.
Further, the drive device 70 has a built-in controller (not shown) for controlling the operation of the pump, and the panel 72.
By operating and instructing switches provided in the blood pump 12, it is possible to control the pressure of air supplied to the blood pump 12, the timing of supply and discharge, and the like.

Next, the case where the auxiliary circulation is carried out by the auxiliary circulation device 10 will be described. As shown in FIG. 4, when performing the auxiliary circulation, the tube 28 of the cannula 14 is inserted, for example, from the right subclavian artery A, and the distal end member 3 is inserted.
4 is located in the left ventricle B and the outlets 52, 54 are located in the aorta C. The insertion of this tube 28 is
As with a conventional cannula, it is done with a stylet. At this time, the presence of the conical portion 30 of the tip member 34 reduces the insertion resistance and also reduces the possibility of damaging the inner surface of the blood vessel. Further, since the discharge valve 60 is easily attached to the outer circumference of the tube 28, resistance when inserting into and removing from the blood vessel is small.

After the tip member 34 and the discharge ports 52, 54 reach the above-mentioned positions, the stylet is removed, and the cannula 14 is deflated by the side tube to connect the cannula 14 and the blood pump 12. The blood pump 12 and the drive device 70 are connected in advance.

Then, the drive device 70 is operated to supply / exhaust air to / from the blood pump 12 in synchronization with the heartbeat of the patient, for example, to increase / decrease the pressure in the air chamber 22. As shown in FIGS. 1 and 4, when the pressure of the air chamber 22 is reduced, the inside of the liquid chamber 20 and the tube 28 becomes a negative pressure state, so that blood flows from the suction port 38 of the tip member 34 through the tube 28 to the liquid chamber. 20 (see FIG. 1A and FIG. 4B). At this time, the side surface portion 48 of the suction valve 40 is deformed so as to be narrowed inward by the inflowing blood and separated from the valve seat 50. Therefore, the inflow of blood from the suction port 38 is not hindered. Moreover, since the total opening area of the four suction ports 38 is larger than the radial cross-sectional area of the tube 28, the inflow of blood is good. On the other hand, the tapered portion 58 of the discharge valve 60 is pressed toward the outer periphery of the tube 28 due to the pressure difference between the tube 28 side and the aorta C side, and covers the discharge ports 52 and 54. Therefore, the discharge port 5
2, 54 are blocked by the discharge valve 60, and the discharge ports 52,
Blood does not flow from 54 into tube 28.
Therefore, the blood pump 12 inhales blood only from the left ventricle B.

Next, when the pressure in the air chamber 22 is increased, the pressure in the liquid chamber 20 becomes relatively low with respect to the air chamber 22, so that the partition wall 1
8 contracts and deforms, and the volume of the liquid chamber 20 decreases (see FIG. 1).
(B) and FIG. 4 (a)). Due to the decrease in the volume of the liquid chamber 20, the blood in the liquid chamber 20 is discharged to the tube 28 side and moves to the tip member 34 side. Side portion 48 of the suction valve 40
Is pressed toward the valve seat 50 by the pressure of the blood in the tube 28, adheres to the valve seat 50, and shuts off the suction port 38. Therefore, the outflow of blood from the suction port 38 is blocked. On the other hand, the pressure of the blood in the tube 28 is equal to that of the discharge valve 6
Since the 0 taper portion 58 is pressed from the inner side to the outer side, the taper portion 58 is opened as shown in FIG. 1B, and the blood flows out from the discharge ports 52 and 54 to the aorta C. Further, the discharge pressure of the blood pump 12 is transmitted to the blood on the aorta C side via the blood in the tube 28, and the blood pressure in the aorta C is increased.

According to this auxiliary circulation device 10, as described above, by increasing or decreasing the pressure of the air chamber 22 of the blood pump 12, the blood of the left ventricle B is sucked from the suction port 38 and the discharge ports 52, 54. To the aorta C. As a result, blood flow from the left ventricle B to the aorta C side is generated, and the flow rate can be assisted. Further, the blood pressure in the aorta C can be increased with the discharge of blood into the aorta C. Moreover, since the pressure in the tube 28 is alternately switched from negative pressure to positive pressure and from positive pressure to negative pressure in accordance with the pressure of the air chamber 22 of the blood pump 12, pulsatile pressure support can be performed. Furthermore, since the blood in the left ventricle B is inhaled when the left ventricle B contracts, the burden on the heart during contraction is reduced. (Experiment) Next, an auxiliary circulation experiment by the auxiliary circulation device 10 of the embodiment will be described.

The cannula 14 is inserted into the aorta through the right subclavian artery of the test dog (mongrel dog), the tip member 34 is placed in the left ventricle, the cannula 14 is deflated, and the blood pump 12 is used.
After completing the connection with the test dog, the test dog was administered with β-blocker to cause severe heart failure, and the blood pump 12 was turned on under the three conditions of sinus rhythm (experiment 1), ventricular pacing (experiment 2) and cardiac arrest (experiment 3). -Off, electrocardiogram, aortic flow, coronary flow and drive pressure of blood pump 12 were measured.
The coronary artery flow rate was measured by inserting both ends of an electromagnetic flow meter inserted in the cannula 14 between the coronary sinus and the right atrium. (Experiment 1) As shown in FIG. 5, by operating the blood pump 12 under sinus rhythm, the aortic flow rate was changed from 1.34 l / min to 1.60 l / min, and the coronary flow rate was 128 ml / min.
It was increased from min to 171 ml / min, and the aortic pressure also showed a waveform of pressurization during diastole and depressurization during systole. The driving pressure of the blood pump 12 on the side of the air chamber 22 is 300 mmHg in the discharge stroke (gauge pressure, the same applies hereinafter) and − in the suction stroke.
At 100 mmHg, discharge stroke time / suction stroke time (S /
The D ratio) is 45%. (Experiment 2) As shown in FIG. 6, by operating the blood pump 12 under ventricular pacing, the aortic flow rate was 0.347 l.
/ Min to 0.407 l / min, coronary flow increased from 22 ml / min to 33 ml / min. Further, a peak was observed in the aortic pressure due to the auxiliary circulation device 10. The driving pressure on the air chamber 22 side of the blood pump 12 is 300 mmHg in the discharge stroke and -100 mmH in the suction stroke.
g, S / D ratio is 45%, and blood pump 12 has a pulse rate of 8
It is 0 BPM. (Experiment 3) As shown in FIG. 7, by operating the blood pump 12 under cardiac arrest, an effective pulsatile flow is generated, and the aortic flow rate is increased from 0.189 l / min to 0.517 l / min. Mean aortic pressure increased from 0 mmHg to 50 mmHg. The driving pressure on the air chamber 22 side of the blood pump 12 is 300 mmHg in the discharge stroke and -100 mmH in the suction stroke.
In g, the S / D ratio is 30%, and the pulse rate of the blood pump 12 is 1
It is 00 BPM.

As is apparent from Experiments 1 to 3 described above, according to the auxiliary circulation device 10, an increase in aortic flow rate and pulsatile pressure assisting are realized at the same time, and this effect is exhibited even during cardiac arrest. As described above, the auxiliary circulation device 10 realizes flow assist and pulsatile pressure assist without increasing the burden on the heart. Moreover, since blood flow and pulsation can be secured as described above even in a cardiac arrest state, it is extremely effective as auxiliary circulation during cardiac arrest.

Although the embodiments have been described above, the present invention is not limited to such embodiments and can be variously implemented without departing from the gist of the present invention. For example, as the blood pump, a reciprocating piston type pump, a diaphragm pump, or the like can be adopted in addition to the above-described pneumatic drive.

In the above embodiment, the discharge valve is opened on the tip side of the tube, but it may be opened on the hand side. By doing so, the resistance during insertion is further reduced.

[0031]

As described above, the cannula according to the first aspect can realize flow rate assist and pulsatile pressure assist without increasing the burden on the heart. Moreover, it is extremely effective as an auxiliary circulation during cardiac arrest.

Next, the cannula according to claim 2 exhibits the same effect as the structure according to claim 1 described above, and since the discharge valve is tubular, it is easy to adhere to the outer circumference of the tube and the tube is There is little resistance when inserting and removing. Next, the cannula according to claim 3 exhibits the same effect as the configuration according to claim 1 or 2, and since the conical portion is provided at the tip of the tube, the resistance during insertion is further reduced. Become.

Next, the cannula according to claim 4 exhibits the same effects as those of the above-mentioned constitutions according to claims 1 to 3, and the total opening area of the suction ports exceeds the radial cross-sectional area of the tube. Therefore, the inhalation resistance is reduced and the inhalation amount can be increased. Further, the auxiliary circulation device according to claim 5 comprises the cannula according to any one of claims 1 to 4, and the pump for sucking fluid from the cannula and discharging the fluid to the cannula. Therefore, the cannula according to claim 1 The auxiliary circulation described above can be performed, and the same effects as described for the cannula according to claim 1 can be exhibited.

[Brief description of drawings]

FIG. 1 is an explanatory view of a structure and an operation of an auxiliary circulation device of an embodiment, FIG. 1 (a) is an explanatory view of a suction stroke, and FIG.
(B) is an explanatory view of a discharge process.

2A and 2B are explanatory views of a structure of a distal end portion of a cannula attached to a circulation device of an embodiment, FIG. 2A is an explanatory view of a distal end member, FIG. 2B is an explanatory view of an intake valve, and FIG. FIG. 2 (c) is a sectional view showing a state in which the suction valve is incorporated in the tip member.

3A and 3B are explanatory views of a structure near a discharge valve of a cannula attached to a circulation device of an embodiment, FIG. 3A is an explanatory view near a discharge port, and FIG. 3B is an explanatory view of a discharge valve. , Fig. 3
(C) is a sectional view of a state in which a discharge valve is attached to the outer circumference of the tube.

4A and 4B are explanatory diagrams of a usage state of the auxiliary circulation device of the embodiment, FIG. 4A is an explanatory diagram of a discharge stroke, and FIG. 4B is an explanatory diagram of an intake stroke.

5 is a graph of electrocardiogram, aortic flow rate, coronary flow rate, and blood pump driving pressure in Experiment 1. FIG.

6 is a graph of electrocardiogram, aortic flow rate, coronary artery flow rate, and blood pump driving pressure in Experiment 2. FIG.

7 is a graph of electrocardiogram, aortic flow rate, coronary flow rate and blood pump drive pressure in Experiment 3. FIG.

[Explanation of symbols]

10 ... Auxiliary circulation device, 12 ... Blood pump (pump), 14 ... Cannula, 20 ... Liquid chamber, 26 ...
..Outflow port, 28 ... Tube, 30 ... Cone part, 38 ... Suction port, 40 ... Suction valve, 50 ...
Valve seat, 52, 54 ... Discharge port, 60 ... Discharge valve.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kozo Suma 1-11-14 Chiyogaoka, Aso-ku, Kawasaki-shi, Kanagawa

Claims (5)

[Claims] 1. A flexible tube having an inlet opening at one end and an outlet provided in a side wall at a set distance from the inlet, and a tube for the inlet relative to the inlet. A flexible membrane suction valve that is installed inside and that allows the fluid to flow from the suction port into the tube and prevents the fluid from flowing out of the tube to the suction port; It is installed over the discharge port,
A cannula comprising: a flexible membrane discharge valve that allows fluid to flow from the inside of the tube to the discharge port and prevents the flow of fluid from the discharge port into the tube. 2. The cannula according to claim 1, wherein the discharge valve is tubular. 3. The suction valve has a substantially frustoconical shape, and has a substantially conical or substantially frustoconical outer shape, the side surface has the suction port, and the inner surface has a substantially conical valve seat that is aligned with the suction valve. The cannula according to claim 1 or 2, wherein a conical portion is provided at one end of the tube. 4. The sum of the opening areas of the suction ports exceeds the radial cross-sectional area of the tube.
The cannula described. 5. The contents of the liquid chamber, comprising: the cannula according to any one of claims 1 to 4, an outflow inlet communicating with the other end of the tube of the cannula, and a liquid chamber communicating with the inflow outlet. An auxiliary circulation device, comprising: a pump for sucking fluid from the cannula via the outflow inlet and discharging the fluid to the cannula via the outflow inlet by changing the product.