JPH02119869A - Blood pump device - Google Patents

Abstract

PURPOSE:To increase a pumping amount of blood without particularly increasing a blood suction pressure, applied to an inflow pipe, and/or its diameter by alternately applying a pressure of contracting and spreading the volume of a pump chamber to the first flexible member from the outside of the pump chamber. CONSTITUTION:In a blood reservoir 10, the first cannula 7 is cut halfway, connecting the second diaphragm 9 to a cut part, and an outer vessel 16 coats the outside of this second diaphragm 9, air-tightly sealing the second operating chamber 11 communicating with the second pumping fluid pipe 15. When a negative pressure is applied to the second operating chamber 11, the second diaphragm 9 is spread increasing the volume of the second pump chamber 14, and blood in the first cannula 7 is sucked to the second pump chamber 14. When a negative pressure is applied to the second pump chamber 14 from an artificial heart 1, blood in the second pump chamber 14 is allowed to flow in the artificial heart 1, and the second diaphragm 9 is contracted. By repeating this action, the reservoir sucks the blood from a left atrium 17 of the heart through an inflow pipe, so that a suction amount is increased of the blood.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) BLOOD PUMP FIELD OF THE INVENTION The present invention relates to blood pumps.

BACKGROUND OF THE INVENTION Blood pumps are connected in parallel to a living body's heart to supplement or replace blood pumping. For example, JP-A-57
Publication No. 99963 discloses a flexible member that partitions a pump chamber with a variable internal volume, an inflow pipe member that communicates with the pump chamber via an inflow valve, and an outflow pipe that communicates with the pump chamber via an outflow valve. A blood pump having a member is presented. This type of blood pump has an air pumping device,
A positive pressure that reduces the volume of the pump chamber and a negative pressure that expands the volume of the pump chamber are alternately applied to the flexible member from outside the pump chamber.

For example, if the inflow tube is connected to the left atrium of a living heart and the outflow tube is connected to the aorta, when the air pumping device applies positive pressure, compressive force is applied to the outer surface of the flexible member, causing the flexible member to contract. The volume of the internal space, that is, the pump chamber, becomes smaller, and the blood in the pump chamber is sent to the aorta through the outflow tube, and when the air pumping device applies negative pressure, a tensile force is applied to the outer surface of the flexible member. The flexible member expands to increase the volume of the pump chamber, and blood from the left atrium is drawn into the pump chamber through the inflow tube.

Since this blood pump operates on the principle of alternately inflowing/outflowing blood into one pump chamber, blood cannot be sucked in (for example, from the left atrium) during the outflow period. For this reason, suction pressure (negative pressure applied to the flexible member) is necessary to suction enough blood.
However, increasing the negative pressure increases the risk of inhaling air from the connection between the heart and the inflow tube. Since the inflow tube is usually inserted into the atrium, it is preferable that the diameter be as small as possible; increasing the diameter makes it difficult to connect the inflow tube to the living body and increases the risk of aspirating air.

Japanese Unexamined Patent Publication No. 55-138459 discloses that two blood pumps are connected in parallel, their inlets are commonly connected, and their discharge ports are commonly connected, and one pump chamber is contracted. When doing so, the other pump chamber is enlarged and this is done alternately. According to this, the inflow/outflow amount of one blood pump can be made smaller than when one blood pump is used as described above, so there is no need to make the negative pressure particularly large, and the diameter of the inflow pipe is not particularly large. It is presumed that a relatively large amount of blood can be pumped without increasing the size.

(Problem to be Solved by the Invention) However, when the two blood pumps described above are connected in parallel, each blood pump has a check valve (an inflow valve and an outflow valve) at the inlet port and the outflow port, respectively. In short, two blood pumps are equipped with a total of four check valves. Blood tends to flow turbulently in the valve area, causing local stagnation in the blood flow and causing thrombus.

Therefore, special consideration must be given to the material of the valve member, its shape and surface treatment, and the shape of the space in which it is placed.The valve member and its surrounding structural parts are extremely expensive in blood pumps, so many check valves are There are great disadvantages to using .

SUMMARY OF THE INVENTION An object of the present invention is to increase the amount of blood pumped without particularly increasing the blood suction pressure applied to the inflow tube and without increasing the diameter of the inflow tube.

[Structure of the invention]

(Means for Solving the Problems) The blood pump device of the present invention includes: a first flexible member that partitions a pump chamber with a variable internal volume; an inflow pipe member that communicates with the pump chamber via an inflow valve; an outflow pipe member that communicates with the pump chamber via an outflow valve; a pumping means that alternately applies pressure to the first flexible member from the outside of the pump chamber to compress and expand the volume of the pump chamber; The blood reservoir has a variable volume chamber divided into squares, and the variable volume chamber communicates with the inflow pipe.

(Function) The pumping means alternately applies a positive pressure that reduces the volume of the pump chamber and a negative pressure that expands the volume of the pump chamber from the outside of the pump chamber to the first flexible member, and the inflow tube is connected to, for example, the left atrium of the living heart, and the outflow tube is connected to the first flexible member. When connected to the aorta, when the pumping means applies positive pressure (during the pumping period), a compressive force is applied to the outer surface of the first flexible member, causing the flexible member to contract and increase the volume of its interior space, i.e., the pump chamber. becomes smaller, the blood in the pumping chamber is pumped through the outflow tube to the aorta, and when the pumping means applies a negative pressure (during the suction period), a tensile force is applied to the outer surface of the first flexible member, so that the first flexible member The member expands, increasing the volume of the pump chamber, and blood from the left atrium is drawn into the pump chamber through the inflow tube.

Thus, during the inhalation period, suction pressure is applied to the variable volume chamber of the reservoir and the inflow tube, and since the variable volume chamber of the reservoir is partitioned by the second flexible member, the blood in the variable volume chamber of the reservoir and the inflow tube blood is aspirated into the pump chamber.

The suction pressure at this time causes the variable volume chamber of the reservoir to contract. That is, the second flexible member of the reservoir contracts. During the discharge period, the pressure of the pump chamber is not applied to the inflow tube and the variable volume chamber of the reservoir. Thereupon, the second flexible member of the reservoir expands due to its restoring force and the inertia of the blood flow in the inflow tube to suck blood from the inflow tube, and the blood is stored in the variable volume chamber. Next, during the suction period of the pump chamber, the negative pressure of the pump chamber is applied to the inflow tube and the variable volume chamber of the reservoir, and the blood in the inflow tube and the variable volume chamber of the reservoir is sucked into the pump chamber, and the variable volume chamber of the reservoir is The second flexible member contracts. Similarly, when the pump chamber has positive pressure, the blood in the inflow tube is sucked into the variable volume chamber of the reservoir and the second flexible member expands, and when the pump chamber has negative pressure, the blood in the inflow tube and the variable volume chamber of the reservoir expands. Blood is sucked into the pump chamber, the second flexible member contracts, and as the pump chamber alternates between positive and negative pressure, the variable volume chamber of the reservoir expands (the second flexible member expands)/contracts ( The second flexible member alternately contracts (contracting), and blood from the left atrium is aspirated into the variable volume chamber of the reservoir via the inflow tube, even during periods of positive pressure in the pump chamber.

In this way, even during the positive pressure period (discharge period) in the pump chamber, the reservoir sucks blood from the left atrium via the inflow tube, so the amount of blood suction increases and the negative pressure in the pump chamber does not become particularly strong. Moreover, the amount of blood to be aspirated can be increased without making the inflow pipe particularly thick.

The reservoir has a second flexible member that defines a variable volume chamber, and does not require a special check valve, so turbulence is less likely to occur in the blood and therefore no thrombus is generated.

In order to further enhance the above-mentioned advantages of the reservoir, another aspect of the present application is proposed.
In one invention, when the pumping means is in the ejection period, a suction pressure applying means applies a pressure to expand the second flexible member of the reservoir from the outside, and when the pumping means is in the inhalation period, the second flexible member of the reservoir is expanded. It further includes a pressure applying means for applying shrinking pressure from the outside.

According to this, the range of expansion/contraction of the variable volume chamber of the reservoir is increased as the positive pressure/negative pressure of the pump chamber is alternately switched, and the above-mentioned advantages of the reservoir are further enhanced.

Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.

(Example) FIG. 1 shows an example of the present invention. The artificial heart 1 houses a first diaphragm 2 in a first working chamber 3 in an outer container,
A known technique in which a first cannula is communicated with the inner space (first pump chamber) 4 of the first diaphragm 2 via a suction check valve 5, and a second cannula 8 is communicated via a discharge check valve 6. In the illustrated state, the first cannula 7 is connected to the left atrium 17 of the heart of the living body, and the second cannula 8 is connected to the aorta 18.

A blood reservoir 10 is inserted into the first cannula, and when the artificial heart 1 is pumped, living body blood is sucked from the left atrium 17 to the first cannula 7, the blood reservoir 109, the artificial heart ill, and the second cannula. It passes through the cannula 8 and into the aorta 18.

Here, the configuration of the pumping device 12 that pumps and drives the artificial heart 1111 will be explained. An air pump 30 rotationally driven by a motor 29 supplies compressed air to the accumulator 20.
When the solenoid valve 22 is open, the compressed air is supplied to the positive pressure chamber 21 of the accumulator 20. Negative pressure chamber 25 of accumulator 20
The air is sucked by an air pump 32 rotationally driven by a motor 31 through a solenoid valve (on-off valve) 26 for adjusting negative pressure. The compressed air in the positive pressure chamber 21 is supplied to the first pumping fluid pipe 13 communicating with the first working chamber 3 of the artificial heart 1 through a positive pressure opening/closing electromagnetic valve (opening/closing valve) 23 , and is supplied to the first pumping fluid pipe 13 communicating with the first working chamber 3 of the artificial heart 1 . Negative pressure is supplied to the first pumping fluid pipe 13 through a solenoid valve (on-off valve) 27 for opening and closing negative pressure.

The pressure in the positive pressure chamber 21 of the accumulator 20 is detected by the pressure sensor 3.
3, the pressure sensor 34 detects the pressure in the negative pressure chamber 34, and the pressure sensor 35 detects the pressure in the first pumping fluid pipe 13, that is, the internal pressure in the first working chamber 3 of the artificial heart 1.

The above-mentioned solenoid valve 22. ' 23, 26.27 and pressure cancelers 33, 34.35 are connected to the CPU as shown in FIG.
(microprocessor) 60, and this controller controls the solenoid valves 23, 27 based on an external synchronization signal or internally generated timing.
are alternately opened and closed, and the electromagnetic valves 22 and 26 are opened and closed based on the pressure detected by the pressure sensors 33 to 35, and the internal pressure of the working chamber 3 of the artificial heart 1 is adjusted to a positive pressure as shown in the DPD shown in FIG. and pulsate to negative pressure. Due to this pressure fluctuation DPD, the first diaphragm 2 of the artificial heart 1 is driven to contract/expand, and negative pressure and positive pressure are intermittently applied to the first cannula 7 and the second cannula 8. This causes biological blood to be pumped.

The above-described components and operation of the pumping device 12 are described in Japanese Patent Application No. 63-6293 filed earlier by the present applicant.
This is what was presented in No. 4.

Next, the implementation part of the present invention will be described. As shown in FIG. 2, the blood reservoir 10 is constructed by cutting the first cannula 7 in the middle and connecting the second diaphragm 9 to the cut part.
and a second working chamber 11 is placed on the outside of the second diaphragm 9 and covered with an outer container 16 to airtightly seal the second working chamber 11,
The second working chamber 11 is communicated with a second pumping fluid pipe 15. When negative pressure is applied to the second working chamber 11, the second
The diaphragm 9 expands to increase the volume of its internal space, that is, the second pump chamber 14, and blood from the first cannula is sucked into the second pump chamber 14. When negative pressure is applied to the second pump chamber 14 from the artificial heart 1, blood in the second pump chamber 14 flows to the artificial heart 1, and the second diaphragm 9 contracts.

The second pumping fluid pipe 15 that communicates with the second working chamber 11 communicates with the positive pressure chamber 21 when the electromagnetic valve (on-off valve) 24 in the positive pressure chamber 21 of the accumulator 20 is open, and When the electromagnetic valve (on-off valve) 27 is open, it communicates with the negative pressure chamber 25 . The internal pressure of the second pumping fluid pipe 15, i.e. the second
The pressure in the working chamber 11 is detected by a pressure sensor 36.

Figure 3 shows the solenoid valves 22~24°26~28 shown in Figure 2.
The configuration of the controller that controls the opening and closing of the is shown. Note that another artificial heart 101 is connected to the living body shown in FIG. 1, and this artificial heart 101 also has a blood reservoir 110.
These artificial heart 101 and blood reservoir 110 are connected to another set of pumping groups W112. This pumping device 112 is controlled in the same manner as the pumping device 12 by a controller (not shown) having a configuration similar to that shown in FIG.

In the following, artificial heart 1. The operation of the blood reservoir 10, the pumping device 12, and the controller shown in FIG. 3 will be described.

Referring to Figure 3, the main body of this controller is the CPU.
60, and an A/D converter 50 is installed at its input/output port.
．． An operation board 40 and a driver 70 are connected.

The pressure sensors 33 to 36 output electrical signals at a level corresponding to the detected pressure.

The levels of these electrical signals (detected pressure) are sampled by the A/D converter 50, converted into digital data, and read by the CPU 60.

Although not shown, the operation board 40 is equipped with a large number of key switches for instructing adjustment of various drive parameters, and various indicators for displaying the values of each parameter at that time. Adjustable parameters include the positive pressure, negative pressure, period of applying positive pressure, period of applying negative pressure, and pulsation cycle of the driving fluid (air) applied to the artificial heart 1, and the period of applying the negative pressure. Includes positive and negative pressure applied to 10. Further, in this example, the timing for applying positive pressure and the timing for applying negative pressure to the artificial heart 1 are generated within the CPU 60, or a synchronization signal (
It is possible to switch between synchronization with "external synchronization" (see FIG. 3).

Each of the six output ports of the CPU 60 has an open (energized onion)
/close (de-energized: off) signals (H/L) are output, these signals are given to the driver 70, and the driver 70 operates the solenoid valves 22 to 24 in accordance with the level of each signal.
．． 26 to 28 are turned on/off, thereby turning on and off the solenoid valves 22 to 28.
24. 26-28 open and close.

- Figures 4a and 4b outline the control operation of the CPU 60 in Figure 3.

Reference is first made to FIG. 4a. When the power is turned on, C, P
U60 first performs initialization (step 1; hereinafter, the word step will be omitted in parentheses). In other words, the contents of the internal memory are cleared, the output signal level during standby is output to the output port, and the initial value (standard value) predetermined in the area (register) in which various parameter values of the internal memory are written.
Set (write) (2.71). Artificial heart I first
The standard value Pspl is written in both the positive pressure reference value register Psp1 that stores the reference value of the positive pressure applied to the working chamber 3 and the positive pressure target value register Psp2 that stores the target value, and the negative pressure applied to the first working chamber 3 is written. A standard value PSNj is written to both the negative pressure reference value register PSN1 that stores the reference value and the negative pressure target value register PSN2 that stores the target value (2),
A standard value P is stored in a positive pressure target value register Psp4 that stores a target value of positive pressure to be applied to the second working chamber 11 of the blood reservoir 10.
A standard value PSN3 is written in a negative pressure target value register PsN4 that stores a target value of negative pressure to be applied to the second working chamber 11 (71).

After completing the initialization (1) and setting of standard values, etc. (2, 71), the CPU 60 reads the input operations of the various key switches provided on the operation board 4o, and reads the set values and detected pressure of various parameters at that time. , operation board 40
Perform upward display output processing (3).

That is, when the switch on the operation board 40 that instructs to update the set value of positive pressure or negative pressure (up or down) is operated, the designated switch for selecting either the artificial heart 1 or the blood reservoir 10 and the positive pressure or negative pressure are activated. When the artificial heart 1 is designated and its positive pressure is designated, the content Psp1 of the positive pressure reference value register Psp1 is updated (up or down) by referring to the designated state of the designated switch that selects one of the two. .5) When +negative pressure is specified, the content PSN1 of the negative pressure reference value register PSNI is updated (up or down) (6, 7). When the blood reservoir 10 is specified and its positive pressure is specified, the content Psp4 of the positive pressure target value register P5P4 is updated (up or down) L (72, 73), and when negative pressure is specified, the negative pressure is The content pHN4 of the target value register PSN4 is updated (up or down) (74.75).

If you do not use an external synchronization signal, follow steps 8 to 9.
Proceed to. When a switch on the operation board 40 that instructs to update parameters such as the positive pressure application period, the negative pressure application period, and 9 pulsation cycles is operated, steps 10 and 11 are executed. That is, the parameters are updated in accordance with the instructions, and the value of the internal timer that determines the beat timing of the artificial heart 1 (timing for switching between positive pressure and negative pressure) is set.

Reference is now made to Figure 4b. Next, the CPU 60 refers to the internal timer or the external synchronization signal to set the first
Check whether it is the timing to switch the drive pressure applied to the working chamber 3 from negative pressure to positive pressure21).If the timing is reached, set 1 (indicating that it is a positive pressure period) in the flag register FII. Writing (76), solenoid valve 23
The solenoid valve 27 is switched from open to closed, and the rise rate of the internal pressure of the first pumping fluid pipe 13 due to this switching (the rate of rise of the internal pressure of the first pumping fluid pipe 13 (the rise rate of the pressure sensor 35 after the time Δtu shown in FIG. 5 after switching) is The detected pressure Psp2 is corrected to a low value when the rising speed is high, and to a high value when the rising speed is low, in accordance with the rising speed (22 to 31: For details of this content,
(Since it is disclosed in the above-mentioned Japanese Patent Application No. 63-62934, detailed explanation here will be omitted.)

If the timing is not right to switch from negative pressure to positive pressure,
Check whether it is the timing to switch from positive pressure to negative pressure (32), and if it is, write 0 (indicating that it is a negative pressure period) to the flag register FII (77), and turn on the solenoid valve 23. The solenoid valve 27 is switched from open to closed, and the solenoid valve 27 is switched from closed to open. Detection pressure P
mn) and corrects the contents PSN2 of the negative pressure target value register P5N2 to a high value when the falling speed is high and to a low value when the falling speed is low in accordance with this falling speed (
33-42: The details of this content are also in the above-mentioned patent application 1983-1986.
934, detailed explanation here will be omitted).

In this way, when the process for switching from the negative pressure period to the positive pressure period or vice versa is completed, or when neither switching timing has been reached, the CPU 60 next controls the artificial heart 51 to 57) to adjust the positive pressure applied to the artificial heart 1.
Execute negative pressure control to adjust the negative pressure applied to l (58
~64).

These contents are disclosed in detail in the aforementioned Japanese Patent Application No. 63-62934. To give an overview, the positive pressure period (F
II=1), the solenoid valve 22 is controlled to open and close so that the pressure detected by the pressure sensor 35 (DPD in FIG. 5) becomes the content of the reference value register Psp1, that is, the detected pressure D
When PD is below the reference value Psp1, the solenoid valve 22 is opened.
When the detected pressure DPD exceeds the reference value pspx, the solenoid valve 22 is closed. On the other hand, the solenoid valve 26 is controlled to open and close so that the detected pressure DPN of the pressure sensor 34 becomes the standard value register PSN2. In other words, when the detected pressure DPN exceeds the standard value PsH2, the solenoid valve 26 is opened and the detected pressure DPN is When the temperature falls below the standard value, the solenoid valve 26 is closed.

During the negative pressure period (FII=O), the pressure detected by the pressure sensor 35 (DPD in FIG. 5) is stored in the reference value register Ps.
The solenoid valve 26 is controlled to open and close so that the content of Nl is reached, that is, the solenoid valve 26 is opened when the detected pressure DPD is equal to or higher than the reference value P8N1, and the solenoid valve 26 is closed when the detected pressure DPD is lower than the reference value P5N1. do. On the other hand, the solenoid valve 22 is controlled to open and close so that the detected pressure DPP of the pressure sensor 33 becomes the standard value register Psp2, that is, the detected pressure DPD becomes the standard value Psp2.
When the detected pressure DPD is below the standard value Psp2, the solenoid valve 22 is opened, and when the detected pressure DPD exceeds the standard value Psp2, the solenoid valve 22 is closed.

Upon exiting the subroutine for pressure control (51 to 63) for the artificial heart 1, the CPU 60 registers the flag register FII.
If it is 0 (negative pressure period of the output pressure of the positive pumping device 12), then
If the content of the register FII is 1 (positive pressure period of the output pressure of the pumping device 12), the subroutine (80) for "negative pressure control" regarding the blood reservoir 10 is executed. After exiting this subroutine, the process returns to step 3 and executes step 3 and subsequent steps. In this way, the CPU 60 performs steps 3 to 6.
4. Repeat steps 78 to 79 or 80.

FIG. 4c shows the contents of the "positive pressure control" subroutine (79) regarding the blood reservoir 10. When proceeding to this subroutine, the CPU 6.0 closes the solenoid valve 28 (cutting off the negative pressure output) (81), and closes the detected pressure DP of the pressure sensor 36.
A is read and the detected pressure DPA is set in the target value register Psp4.
It is checked whether the content of Psp is equal to or higher than 4 (82).

When DPA is Psp4 or more, the solenoid valve 24 is closed (positive pressure output cutoff) (84), and when DPA is less than Psp4, the solenoid valve 24 is opened (positive pressure output) (83), and the process returns to step 3 ( return).

FIG. 4d shows the contents of the "negative pressure control" subroutine (80) regarding the blood reservoir 10. When the process proceeds to this subroutine, the CPU 60 closes the solenoid valve 24 (cutting off positive pressure output) (85), reads the detected pressure DPA of the pressure sensor 36, and determines whether the detected pressure DPA is the content P of the target value register PsN4.
Checks whether it is SN4 or less (86). If DPA is Psp4 or less, the solenoid valve 28 is closed (negative pressure output cutoff) (88), and if DPA exceeds Psp4, the solenoid valve 28 is opened. (Negative pressure output) (87), step 3
Return to (return).

By the control operation of the CPU 60 explained above, the driving pressure DPD shown in FIG. 5 is applied to the first working chamber 3 of the artificial heart 1, and the driving pressure DPD shown in FIG. The driving pressure DPA shown is given, and the solenoid valves 23, 2
4, 27, and 28 are opened and closed as shown in FIG. (
A pulsating pressure (absolute pressure) is applied.

Accordingly, referring again to FIGS. 1 and 2, when the artificial heart 1 applies negative pressure to the first cannula 7 (blood suction), positive pressure is applied to the second working chamber 11 of the blood reservoir 1o, and the The second diaphragm 9 contracts, and the first cannula 7
The blood drawn from the left atrium 17 and the blood stored in the blood reservoir 10 are drawn into the artificial heart 1. Artificial heart 1 is the second
When applying positive pressure to the cylinder 8 (blood discharge), negative pressure is applied to the second working chamber 11 of the blood reservoir 10, the second diaphragm 9 expands, and the second pump chamber 14 becomes negative pressure. Blood is aspirated from the left atrium 17. Blood is thereby stored in the second pump chamber 13. This stored blood is then sucked into the artificial heart 1 together with the blood sucked from the left atrium 17 by the cannula 7 during the next suction period of the artificial heart 1.

Therefore, the amount of blood suctioned by the artificial heart 1 is substantially increased without particularly increasing the negative pressure applied to the first working chamber 3 of the artificial heart 1 during the suction period.

Next, other embodiments and modifications of the present invention will be described. In the embodiment described above, the electromagnetic valves 24 and 28 apply a pulse pressure to the second working chamber of the blood reservoir 10 that is in the opposite phase to the pulse pressure applied to the first working chamber 3 of the artificial heart 1. In the second embodiment of the present invention, the solenoid valve 24 is omitted. This second embodiment will be described. In the second embodiment, as shown in FIG. 6a, only the electromagnetic valve 28 is provided, and the second pumping fluid pipe 15 is communicated with the atmosphere through a minute orifice 37. In this second embodiment, the CPU 60 executes the "positive pressure control" subroutine (79) shown in FIGS. 4b and 4c.
shall perform the omitted control operation. Other control operations are similar to those in the previous embodiment.

In this second embodiment, when the artificial heart 1 applies negative pressure to the first cannula 7 (blood suction), the negative pressure is applied to the second working chamber 11 of the blood reservoir 10, causing the second diaphragm 9 to contract. Blood sucked from the left atrium 17 by the first cannula 7 and blood stored in the blood reservoir 10 are sucked into the artificial heart 1. The artificial heart 1 applies positive pressure to the second cannula 8 (when discharging blood, negative pressure is applied to the second working chamber 11 of the blood reservoir 10, the second diaphragm 9 expands, and the second pump chamber 14 is under negative pressure) This aspirates blood from the left atrium 17. This causes the blood to accumulate in the second pump chamber 13. Then, during the next aspiration period of the artificial heart 1, this accumulated blood is aspirated from the left atrium 17 by the cannula 7. The artificial heart 1 is sucked into the artificial heart 1 along with the blood.

Therefore, in this second embodiment as well, the amount of blood suctioned by the artificial heart 1 is substantially increased without particularly increasing the negative pressure applied to the first working chamber 3 of the artificial heart 1 during the suction period.

In the third embodiment, as shown in FIG. 6b, both the solenoid valves 24 and 28 are omitted, that is, the pumping device 12 is
A second pumping fluid pipe 15 is connected to the negative pressure chamber of the accumulator 20 in a structure substantially similar to that of a conventional pumping device.
communicates with the second working chamber of the blood reservoir 10 via.

In order to make the negative pressure applied to the second working chamber 11 of the blood reservoir 10 lower than the negative pressure applied to the first working chamber 3 of the artificial heart 1, the second pumping fluid pipe 15 is provided with a device that suppresses the propagation of negative pressure. An adjustable throttle valve (orifice) 38 and a minute orifice 37 for communicating atmospheric air are provided.

In this third embodiment, when the artificial heart 1 applies negative pressure to the first cannula 7 (blood suction), the second
The negative pressure is applied to the working chamber 11, causing the second diaphragm 9 to contract, and blood drawn from the left atrium 17 by the first cannula 7 and blood stored in the blood reservoir 10 are drawn into the artificial heart 1. The artificial heart 1 applies positive pressure to the second cannula 8 (
blood ejection), the second working chamber 1 of the blood reservoir 10
1, the second diaphragm 9 expands and the second pump chamber 14 becomes negative pressure, which causes the left atrium 17
Suction more blood. This causes the blood to flow into the second pump chamber 1.
Store in 3. This stored blood is then sucked into the artificial heart 1 together with the blood sucked from the left atrium 17 by the cannula 7 during the next suction period of the artificial heart 1.

Therefore, in this second embodiment as well, the amount of blood suctioned by the artificial heart 1 is substantially increased without particularly increasing the negative pressure applied to the first working chamber 3 of the artificial heart 1 during the suction period.

In a simple embodiment, the second pumping fluid pipe 15 of the third embodiment is also omitted, and the outer container 16 of the blood reservoir 10 is made airtight. In this modification, when the artificial heart 1 applies negative pressure to the first cannula 7 (blood suction), the negative pressure is applied to the second pump chamber 14 of the blood reservoir 10, causing the second diaphragm 9 to contract. Accordingly, the second working chamber 1
1 becomes a negative pressure, and the blood sucked from the left atrium 17 by the first cannula 7 and the blood stored in the blood reservoir lO are sucked into the artificial heart l. When the artificial heart 1 applies positive pressure to the second cannula 8 (blood ejection), the pressure in the second working chamber 11 of the blood reservoir 10 attempts to return to normal pressure, causing the second diaphragm 9 to expand. room 14
becomes a negative pressure, which sucks blood from the left atrium 17.

Blood is thereby stored in the second pump chamber 13. This stored blood is then sucked into the artificial heart 1 together with the blood sucked from the left atrium 17 by the cannula 7 during the next suction period of the artificial heart 1.

Therefore, in this modification as well, the amount of blood suctioned by the artificial heart 1 is substantially increased even if the negative pressure applied to the first working chamber 3 of the artificial heart 1 during the suction period is not particularly large.

When the second diaphragm 9 has a relatively high self-restoring force, the outer container 16 may be omitted, or the second diaphragm 9 may be simply provided with an outer container that communicates with the atmosphere. In this modification, when the artificial heart 1 applies negative pressure to the first cannula 7 (blood suction), the blood reservoir 10
The negative pressure is applied to the second pump chamber 14 of the artificial heart, causing the second diaphragm 9 to contract, and the blood sucked from the left atrium 17 by the first cannula 7 and the blood stored in the blood reservoir 10 to the artificial heart l.
is attracted to. When the artificial heart 1 applies positive pressure to the second cannula 8 (blood ejection), the second diaphragm 9 expands in an attempt to return to its original shape, resulting in negative pressure in the second pump chamber 14, which causes blood to flow from the left atrium 17. aspirate. As a result, blood is stored in the second pump chamber 13.

This stored blood is then sucked into the artificial heart 1 together with the blood sucked from the left atrium 17 by the cannula 7 during the next suction period of the artificial heart 1.

Therefore, in this modification as well, the amount of blood suctioned by the artificial heart 1 is substantially increased without particularly increasing the negative pressure applied to the first working chamber 3 of the artificial heart 1 during the suction period.

〔Effect of the invention〕

In any case, the blood pump device of the present invention includes: a first flexible member (2) that defines a pump chamber (4) with a variable internal volume; Inflow pipe member (7); Outflow pipe member (8) that communicates with the pump chamber (4) via the outflow valve (6); Pumping means (12) that alternately applies pressure to contract (positive pressure) and pressure to expand (negative pressure) the volume of the pump chamber (4); and a variable volume chamber (14) partitioned by the second flexible member (9). ), the variable volume chamber (14) communicating with the inflow tube (7); and a pumping means (12) configured to pump a first flexible tube from the outside of the pumping chamber (4). A positive pressure that reduces the volume of the pump chamber (4) and a negative pressure that expands the volume of the pump chamber (4) are alternately applied to the member (2), and the inflow tube (7) is inserted into the left atrium (
17) and the outflow tube (8) is connected to the aorta (18), the outer surface of the first flexible member (2) when the pumping means (12) applies positive pressure (during the ejection period). As a compressive force is applied to the first flexible member (2), the first flexible member (2) contracts and the volume of its internal space, that is, the pump chamber (4) becomes smaller, and the blood in the pump chamber (4) passes through the outflow tube (8) and flows into the aorta (18). ), and the pumping means (12) applied negative pressure (
During the suction period), a tensile force is applied to the outer surface of the first flexible member (2), causing the first flexible member (2) to expand and fill the pump chamber (4).
) increases in volume, and blood from the left atrium (17) is sucked into the pump chamber (4) through the inflow tube (7).

Therefore, during the inhalation period, the suction pressure is riser A (10)
The variable volume chamber (14) of the reservoir (10) joins the variable volume chamber (14) of the reservoir (10) and the inflow tube (7) of the second flexible member (
9), blood in the variable volume chamber (14) of the reservoir (10) and blood in the inflow tube (7) are sucked into the pump chamber (4°). The suction pressure at this time causes the variable volume chamber (14) of the reservoir (10) to contract. That is, the second flexible member (9) of the reservoir (10) contracts.

During the discharge period, the inflow pipe (8) and the
The pressure of the pump chamber (4) is not applied to the variable volume chamber (14) of 10). Then, the second flexible member (9) of the reservoir (10) expands due to its restoring force and the inertia of the blood flow in the inflow tube (7), and sucks the blood in the inflow tube (7). It is stored in the variable volume chamber (14). Next, during the suction period of the pump chamber (4), the negative pressure of the pump chamber (4) increases the inflow pipe (7) and the variable volume chamber (10) of the reservoir (10).
14), the inlet pipe (7) and the reservoir (10)
The blood in the variable volume chamber (14) of is sucked into the pump chamber (4), the variable volume chamber (14) of the reservoir (10) contracts and the second flexible member (9) contracts. Similarly, when the pump chamber (4) has positive pressure, the blood in the inflow tube (7) is sucked into the variable volume chamber (14) of the reservoir (10), the second flexible member (9) expands, and the pump When the chamber (4) is under negative pressure, the variable volume chamber (14) of the inflow pipe (7) and the reservoir (10)
) is sucked into the pump chamber (4) and the second flexible member (9
) contracts, and as the pump chamber (4) alternates between positive pressure and negative pressure, the variable volume chamber (14) of the reservoir (10) expands (the second flexible member 9 expands) and contracts (the second flexible member 9 expands). 2 flexible member 9
During positive pressure periods in the pump chamber (4), blood from the left atrium (17) flows through the inflow tube (7) into the variable volume chamber (14) of the reservoir (10). be attracted.

In this way, even during the positive pressure period (discharge period) of the pump chamber (4), the reservoir (10) is connected to the left atrium (17) via the inflow pipe (7).
), the amount of blood suctioned increases without increasing the negative pressure in the pump chamber (4) or making the inflow pipe (7) particularly thick. do. The reservoir (10) has a second flexible member (9) that partitions the variable volume chamber (14), and does not require a special check valve, so it is difficult to cause turbulence in the blood and therefore prevents blood clots. Does not occur.

Further, another invention of the present application further includes a suction pressure applying means (28) that applies expanding pressure from the outside to the second flexible member (9) of the reservoir (lO) when the pumping means (12) is in the discharge period. and a pressure application means (24) that applies pressure to contract the second flexible member (9) from the outside during the suction period of the pumping means (12), so that the positive pressure in the pump chamber (3) is reduced. The width of expansion/contraction of the variable volume chamber (14) of the reservoir (10) becomes larger as the negative pressure is alternately switched, and the above-mentioned advantages of the reservoir (10) are further enhanced.

[Brief explanation of the drawing]

FIG. 1 is an external view showing the configuration of an embodiment of the present invention, and a portion thereof shows a longitudinal section. FIG. 2 is an enlarged longitudinal cross-sectional view of the blood reservoir 10 shown in FIG. FIG. 3 is a block diagram showing the configuration of a controller that is connected to the pressure sensors 33-36 shown in FIG. 1 and controls opening and closing of the electromagnetic valves 22-24 and 26-28 shown in FIG. 1. Figures 4a, 4b, 4c and 4d are the third
It is a flowchart which shows the control operation of CPU60 shown in the figure. FIG. 5 is a time chart showing the relationship between the detected pressures of the pressure sensors 33 to 36 shown in FIG. 1 and the opening and closing of the electromagnetic valves. FIG. 6a is a longitudinal sectional view of another embodiment of the present invention, showing the main parts that are different from the embodiment shown in FIGS. 1 to 3. FIG. FIG. 6b is a longitudinal sectional view showing the main parts of another embodiment of the present invention, which are different from the embodiment shown in FIGS. 1 to 3. FIG. 1-Artificial heart 2: First diaphragm (first flexible member) 3: First working chamber 4: First pump chamber (pump chamber) 5: Inflow check valve (inflow valve) 6: Outflow check valve Stop valve (outflow valve) 7: First cannula (inflow pipe member) 8: Second cannula (outflow pipe member) 9: Second diaphragm (second flexible member) 10: Blood reservoir (reservoir) 11: Second Working chamber 12: Pumping device (pumping means) 13: First pumping fluid pipe 14: Second pump chamber (variable volume chamber) 1
5: Second pumping fluid pipe 16: Outer container 17: Left atrium 18 Two aortas - 20 = Accumulator 21: Positive pressure chambers 22-23: Solenoid valve
24: Solenoid valve (pressure applying means) 25: Negative pressure chamber
26-27: Solenoid valve 28: Solenoid valve (suction pressure applying means) 29: Motor 30: Air pump 31: Motor 32: Air pump 33-36: Pressure sensor 37: Orifice 38: Variable throttle valve 1
01: Artificial heart 110: Blood reservoir 11
2: Pumping device

Claims (2)

[Claims] (1) A first flexible member that partitions a pump chamber with a variable internal volume; An inflow pipe member that communicates with the pump chamber via an inflow valve; An outflow pipe member that communicates with the pump chamber via an outflow valve; The pump a pumping means that alternately applies pressure to contract and expand the volume of the pump chamber from the outside of the chamber to a first flexible member; and a variable volume chamber partitioned by a second flexible member; A blood pump device comprising: a blood reservoir in communication with the inflow tube. (2) a first flexible member that partitions a pump chamber with a variable internal volume; an inflow pipe member that communicates with the pump chamber via an inflow valve; an outflow pipe member that communicates with the pump chamber via an outflow valve; the pump Pumping means that alternately applies pressure for contracting and expanding the volume of the pump chamber from the outside of the chamber to the first flexible member; a variable volume chamber partitioned by a second flexible member; a blood reservoir communicating with the inflow tube; suction pressure applying means applying pressure from outside of the variable volume chamber to the second flexible member to expand the volume of the variable volume chamber when the pumping means is applying the contracting pressure; A blood pump apparatus comprising: a pressure applying means for applying pressure from outside of the variable volume chamber to the second flexible member to contract the volume of the variable volume chamber when the pumping means is applying the expanding pressure.