JPS641148B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a device for driving a medical pump such as an artificial heart or an intra-aortic balloon pump that alternately supplies positive pressure and negative pressure, and particularly relates to a device for driving a medical pump such as an artificial heart or an intra-aortic balloon pump. This invention relates to a fluid drive device that uses gases that are safe for blood, such as helium gas and carbon dioxide gas.

[Conventional technology]

Pressure-driven medical pumps, such as artificial hearts and intra-aortic balloon pumps, are driven by alternately supplying positive and negative pressure, and are driven to give blood a pulsating flow that closely resembles the pulsation of a living heart. It is important from a safety point of view to For example, various types of artificial hearts are known, such as a diaphragm type, a sack type, and a piston type, and these are generally driven by receiving pressure pulses from a fluid such as air. In order to drive a pressure-driven medical pump such as an artificial heart under the best conditions depending on the condition of a living body, a drive device that outputs accurate pressure according to the conditions at a predetermined timing is required. That is, a drive device that can accurately and quickly set the heart rate, positive pressure, negative pressure, duration or duty ratio for applying positive pressure and negative pressure to predetermined values to predetermined values is desirable.

By the way, in this type of pressure-driven medical pump such as an artificial heart, positive pressure and negative pressure are alternately applied to the medical pump, so fluid must be alternately sucked in and discharged, resulting in a large amount of fluid. of driving fluid will be consumed. Therefore, air is generally used as the driving fluid. however,
In this type of fluid-driven medical pump, the driving fluid and blood are separated only by a thin membrane, so if a failure that ruptures this membrane occurs, parts of the membrane may be damaged. Drive fluid may leak through the In this case, if the driving fluid is air, blood will coagulate, putting the patient's life at risk.

In addition, in a balloon pump, in order to improve responsiveness, the driving fluid that directly drives the balloon pump is replaced with a fluid other than the atmosphere using an isolator. In this case, air accumulated inside the piping between the isolator and the balloon pump when the isolator and the balloon pump are connected is manually discharged. For this reason, skill is required to replace the driving fluid, and filling the piping with the driving fluid after connecting the device takes time and is troublesome.

〔the purpose〕

Therefore, in the present invention, a pressure-driven medical pump driven by pressure pulses from an artificial heart or the like is designed to be safe even if the membrane that separates blood from the driving fluid that drives the pump is ruptured. In addition to having a configuration that allows the driving fluid to be replaced with a fluid other than the atmosphere, the aim is to make it possible to quickly and easily fill the piping with the driving fluid to be replaced even immediately after connecting the device. do.

〔composition〕

In the present invention, a pressure adjustment device for pressure control using the atmosphere as a driving fluid and a pressure adjustment device for gas control converting pressure changes in atmospheric pressure into pressure changes in other fluids are provided. The fluid in the device drives a medical pump. here,
A pressure regulator for pressure control consists of a positive pressure source, a positive pressure switching solenoid valve whose input end is connected to the output end of the positive pressure source, a negative pressure source, and an input end connected to the output end of the negative pressure source. Consisting of a negative pressure switching solenoid valve whose output end is connected to the output end of the positive pressure switching solenoid valve, and pressure control electronic control means for controlling the positive pressure switching solenoid valve and the negative pressure switching solenoid valve. did. In addition, the gas control pressure adjustment device includes a medical pump driving means that separates an input end and an output end via a membrane that changes depending on the applied pressure, a gas supply means, an output side of the medical device driving means, and a gas supplying means. a gas supply solenoid valve connected to the supply means; an air discharge solenoid valve whose input end is connected to the output side of the medical pump drive means and whose output end is open to the atmosphere or a negative pressure system; and a gas supply solenoid valve. It consists of a valve and an electronic control means for gas control that controls the opening and closing of the solenoid valve for air discharge.

Therefore, a fluid different from the atmosphere can be used as the driving fluid that directly drives the medical pump.
Therefore, the driving fluid can be a fluid that is safe for blood, such as helium gas or carbon dioxide gas.

Here, it is necessary to consume a large amount of fluid to adjust the pressure, but if a safe driving fluid such as helium gas is used in all systems, a large amount of driving fluid will be required. However, in the present invention, the driving fluid supplied by the gas supply means to directly drive the medical pump is separated from the pressure regulating device for pressure control, which directly adjusts the pressure by the membrane of the medical pump driving means. Therefore, there is no need to prepare a large tank for the driving fluid, and the device does not become large.

In addition, when driving this type of medical pump using a driving fluid such as helium gas, unless a special method is used, such as assembling the device in a room filled with gas, the medical pump cannot be used immediately after the device is assembled. There is air in the connected tube. Therefore, even if a medical pump such as an artificial heart is driven by a driving fluid such as helium gas, the stability will be slightly lowered immediately after the device is assembled. However, in the present invention, according to instructions from the setting means, the electronic control device for pressure control controls the electromagnetic valve for switching between positive pressure and negative pressure so as to move the membrane of the medical pump driving means to a large extent, and the electronic control device for gas control Since the device controls the gas supply solenoid valve and the air discharge solenoid valve to alternately supply gas and exhaust air, the air remaining in the tube is quickly removed even immediately after the device is assembled. The fluid in the tube will be replaced by the fluid supplied by the gas supply means. Therefore, safety will not be compromised even immediately after the device is connected.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the system configuration of the artificial heart and balloon pump drive device. Referring to Figure 1,
60L and 60R are artificial hearts, and 60B is an intra-aortic balloon pump. Although the fluid drive unit FDU is equipped with three fluid drive output terminals, it is actually impossible to imagine a situation in which the artificial hearts 60L and 60R and the balloon pump 60B are used at the same time, so only two of them operate at the same time. It is structured so that it can be used. Fluid drive unit
The remote control boat REM, light LMP, and video camera CAM are connected to the electronic control unit ECU that controls the FDU. The signal output end of the video camera is connected to a monitor TV. The remote operation board REM and electronic control unit ECU are connected with an optical fiber cable FBO.

FIG. 2 shows the configuration of the fluid drive unit FDU shown in FIG. 1. First, to explain the outline, this unit FDU includes a compressor 71, a vacuum pump 72,
It is equipped with pneumatic control mechanisms ADUL and ADUR, gas drive mechanisms GDUL, GDURA, and GDURB, a helium gas tank HTA, and a pressure reducing valve 61.
The input end of the gas drive mechanism GDUL is a pneumatic control mechanism.
It is connected to the output end of ADUL, and the input ends of gas drive mechanisms GDURA and GDURB are commonly connected to the output end of pneumatic control mechanism ADUR.
Output ends of the gas drive mechanisms GDUL, GDURA, and GDURB are connected to artificial hearts 60L, 60R and balloon pump 60B, respectively.

The pneumatic control mechanism ADUL will be explained. This mechanism includes six solenoid valves 51, 52, 53, 54, 5.
5 and 56 are provided. Solenoid valves 51, 52
and 53 are used for positive pressure generation, and solenoid valve 5
4, 55 and 56 are used for negative pressure generation.
Solenoid valves 51 and 52 are accumulator AC1
The electromagnetic valves 54 and 55 are provided inside the accumulator AC2.
The input ends of the solenoid valves 51 and 53 are connected to the compressor 7.
The input ends of the solenoid valves 54 and 56 (on the downstream side in terms of the fluid flow direction) are connected to the negative pressure output end of the vacuum pump 72, and the solenoid valves 52, 53, 55 are connected to the negative pressure output end of the vacuum pump 72. and 56 are connected to the output end of the pneumatic control mechanism ADUL. PS1 and PS2 are pressure sensors for detecting the pressure inside the accumulators AC1 and AC2, respectively. Air pressure control mechanism
The configuration of ADUR is the same as ADUL.

Next, the gas drive mechanism GDUL will be explained. This mechanism is equipped with electromagnetic valves 57, 58, 59, a fluid isolator AGA, and the like. Mechanical valve VA1 is installed on the primary side (air side) of the fluid isolator AGA.
The output end of the air pressure control mechanism ADUL is connected via the air pressure control mechanism ADUL. The solenoid valve 57 has an input end connected to the primary side of the fluid isolator AGA, and an output end open to the atmosphere. The input end of the electromagnetic valve 59 is connected to the output end of the pressure reducing valve 61, and the output end is connected to the secondary side of the fluid isolator AGA. The solenoid valve 58 has an input end connected to the secondary side of the fluid isolator AGA, and an output end connected to the accumulator AC.
Connected to the inside of 2. fluid isolator
Pressure sensors PS3 and PS4 are provided on the primary and secondary sides of the AGA, respectively. The configuration of the gas drive mechanism GDURA and GDURB is GDUL
It is similar to

Figure 3 shows the configuration of the fluid isolator AGA included in the gas drive mechanism GDURB. This will be explained with reference to FIG. Simply put, in the AGA, a diaphragm 83 sandwiched between housings 81 and 82 separates a space communicating with the primary port 81a and a space communicating with the secondary port 82a. It is becoming possible to shift.

A plate 84 is provided at the center of the diaphragm 83.
and 85 are attached to sandwich it.
86 is a bolt for fixing the plates 84 and 85. A regulating member 63 for adjusting the amount of deviation of the plate 85 is attached to the center of the housing 81 . The regulating member 63 is formed with screws 63a and 63b, and is engaged with the housing 81 at the screw 63b.

When the regulating member 63 is rotated, the engagement position changes and the regulating member 63 moves left and right. If they move to the left, the range of movement of the plates 84, 85 becomes larger, and if they move to the right, the range of movement of the plates 84, 85 becomes smaller. M1 is a DC motor. A worm gear 62 is coupled to the drive shaft of the DC motor M1, and the worm gear 62 meshes with a screw 63a. Therefore, by driving the motor M1, the movement range of the plates 84, 85 changes. The motor M1 is connected to the base plate 90
The flange portion 81b of the housing 81 is fixed through the flange portion 81b of the housing 81. 89 is an O-ring, and 87 and 88 are bolts for fixing the housings 81 and 82.

The fluid isolator AGA provided in the gas drive mechanisms GDUL and GDURA has the same configuration as that shown in FIG. 3, except that the motor M1 is omitted.

Figure 4 shows the electronic control unit shown in Figure 1.
The configuration of the ECU is shown. Referring to FIG. 4, the electronic control unit ECU includes control units CON1,
CON2 and CON3, remote control receiving unit
SRU, main unit side operation board MOB, display unit
DSPU and scope & lamp control unit
I'm getting used to it at SLCU.

Control unit CON1 is a pneumatic control mechanism
ADUL and ADUR pressure sensors PS1 and PS
By monitoring the output signal of 2, the accumulator AC
The solenoid valves 51 and 52 are controlled to open and close so that the pressure inside AC 1 and AC 2 matches the set pressure.

Control unit CON2 is a pneumatic control mechanism
ADUL and ADUR solenoid valves 52, 53, 55
and 56 are controlled to open and close at predetermined timings according to the set heartbeat cycle, left and right Systolic Duration, duty, etc.

The control unit CON3 has a gas drive mechanism GDUL,
Controls GDURA and GDURB solenoid valves 57, 58 and 59. However, GDURA and GDURB are not controlled at the same time. GDUL, GDURA and GDURB are controlled by pressure sensors PS3 and
This is done by monitoring only the output signal PG1, PG2 or PS4 of PS4. Also, in controlling GDURB, the motor M1 is controlled.

The display unit DSPU consists of a large number of 7-segment displays, and the control units CON1 and CON
2 and CON3. The main unit side operation board MOB is the control unit CON1, CON2,
CON3 and scope & lamp control unit
Connected to SLCU. Each output line of the remote control receiving unit SRU is connected in the same way as the corresponding signal line of the main body side operation board MOB.

FIG. 5 shows the configuration of the control unit CON3 of FIG. 4. This will be explained with reference to FIG. This unit CON3 is a microcomputer unit.
It is composed mainly of CPU3. Main unit side operation board MOB and remote control receiving unit SRU
Connector J12 to which is connected is buffer BF3
and via the chattering removal circuit CH3,
Connected to the input port of CPU3. The signal applied to connector J12 is from the main unit side operation board.
These include an air purge instruction signal, an auxiliary heart/balloon pump selection signal, etc. from the MOB.

An A/D converter Z16B with the same configuration as CPU3 or Z16 is connected, and gas drive mechanisms GDUL and GDURA are connected to the analog signal input terminal of Z16B.
And the output terminal of the pressure sensor equipped on GDURB is connected. MD1 is a circuit for driving the stroke adjustment motor M1. By controlling the two input terminals of MD1, motor M
1 can be controlled to rotate forward, reverse, or stop.

Buffer Z1 is installed on the nine output ports of CPU3.
Solid state relays SSR13 to SSR21 are connected via 5D, Z15E and Z15F. The output terminals of SSR13, SSR14 and SSR15 are connected to the gas drive mechanism GDUL, respectively.
It is connected to the solenoid valves 57 of GDURA and GDURB, and the output terminals of SSR16, SSR17 and SSR18 are connected to the gas drive mechanism GDUL, respectively.
It is connected to the solenoid valves 59 of GDURA and GDURB, and the output terminals of SSR19, SSR20 and SSR21 are connected to the gas drive mechanism GDUL, respectively.
It is connected to the GDURA and GDURB solenoid valves 58.

6a and 6b schematically show the operation of the microcomputer unit CPU3. Chapter 6a
Figure 6 shows the main routine, and Figure 6b shows the air venting subroutine.

This will be explained with reference to FIG. 6a. When the power is turned on, the memory and output port are initialized, and a check is made to see if there is an air venting instruction (S18 is on), and if there is an instruction, the air venting subroutine is executed. Check the state of switch S19 to determine whether the right drive system is in auxiliary heart mode or balloon pump mode.

In case of cardiac assist mode, pressure sensor PS3 and PS
4 output signals PG1 and PG2. When the level of PG1 is higher than PG2 by a predetermined value Ref3, the solenoid valve 59 is set to open and the helium tank is opened.
Helium gas from HTA fluid isolator AGA
Supplied to the secondary side of Since a relatively high pressure (for example, 150 mmHg) appears in the output of the pressure reducing valve 61, opening the solenoid valve 59 increases the pressure on the secondary side of the AGA.

If the difference between PG1 and PG2 is less than Ref3, the solenoid valve 59 is set to close. Also, the level of PG2
If Ref4 or more is greater than PG1, the solenoid valve 58 is set open to reduce the secondary pressure of the AGA.
If the difference between PG1 and PG2 is less than a predetermined value, the solenoid valve 58
Set to closed.

The operation timing of the cardiac assist mode is shown in FIG. Normally, the plates 84, 85 (and diaphragm 83) of the fluid isolator AGA vibrate in response to pressure changes from the pneumatic control mechanism without hitting the housings 81, 82 or the regulating member 63. In this condition, the fluid isolator
There is no large difference in pressure between the primary and secondary sides of the AGA.

However, if a fluid leak occurs on the secondary side of the fluid isolator AGA (helium gas leaks to the atmosphere side), the pressure on the secondary side decreases, and the plates 84, 8
The vibration position of No. 5 moves to the right in FIG.
When the movement exceeds a predetermined value, the plate 84 comes into contact with the housing 82. When plate 84 contacts housing 82, fluid isolator AGA
Since the fluid pressure on the secondary side of will not increase any further, 1
A difference occurs between the pressure PG1 on the next side and the pressure PG2 on the secondary side.

Further, after the solenoid valve 59 is opened, the secondary side pressure PG2 of the AGA increases, and the vibration positions of the plates 84 and 85 move to the left in FIG. 63 or the housing 81, and PG1<PG2. Therefore, by controlling the solenoid valves 58 and 59 so that the difference between PG1 and PG2 is maintained below a predetermined value as described above, the secondary side pressure PG2 is maintained within a predetermined range, and the plates 84, 85 are can be driven so that the vibration does not stop.

When the switch S19 is set to the balloon side, the balloon mode is entered. In this example,
In the balloon mode, a method of monitoring only the secondary pressure PG2 is used. This monitors PG2 and controls solenoid valves 58, 59 and motor M1 so that the strokes of plates 84 and 85 vibrate within a position range regulated by housing 82 and regulating member 63.

In this mode, the pressure PG2 has a waveform as shown in FIG. That is, when the driving pressure changes from negative pressure to positive pressure, a pressure equal to PG1 appears at PG2, and the pressure drops (saturates) when the plate 84 contacts the housing 82. Further, when the driving pressure changes from positive pressure to negative pressure, a pressure equal to PG1 appears at PG2, and the pressure increases (the absolute value decreases) (saturates) when the plate 85 contacts the regulating member 63.

Returning to Figure 6a, first, above PG2,
Find the difference in lower saturation pressure, that is, PST in Figure 8. PST corresponds to the movement range (stroke) of the plates 84 and 85. When PST is larger than the stroke upper limit value, the motor M1 is driven in normal rotation to drive the regulating member 63 to the right in FIG.
When PST is smaller than the lower stroke limit, the motor M1 is driven in the reverse direction to drive the regulating member 63 to the left in FIG. In this way, the strokes of the plates 84, 85 are first adjusted within a predetermined range.

There is a reason for making stroke adjustments. Firstly, the capacity of the balloon pump differs depending on the type of patient (adult, child, etc.), so when driving a small-capacity balloon pump, the stroke should be shortened to eliminate unnecessary movements and the balloon pump should be operated. The other reason is to limit the amount of gas flowing out in the event that the balloon pump ruptures.

Next, the negative side saturation pressure PG2L (absolute value) is compared with a predetermined upper and lower limit value. PG2L
If is larger than the upper limit, the solenoid valve 58 is set to open, and if it is smaller than the upper limit, the solenoid valve 58 is set to closed. Further, if PG2L is smaller than the lower limit value, the solenoid valve 59 is set to open, and if it is larger than the lower limit value, the solenoid valve 59 is set to close. This results in
PG2L is maintained between the upper limit value and the lower limit value, and is controlled so that the amount of helium gas on the secondary side of the fluid isolator AGA does not change significantly.

Next, the air venting operation will be explained. Switch S18
When turned on, the air purge subroutine is executed.

This will be explained with reference to FIG. 6b. In this example, first, the solenoid valves 57 (R, L) are opened to open the primary side of the fluid isolator AGA to the atmosphere. Then,
Set the counter COX (internal register) to a predetermined value (10 in this example). Clear and start the timer, close solenoid valve 58, and set solenoid valve 59 to open. When the timer times out, after clearing and starting the timer, the solenoid valve 58 is opened, and the solenoid valve 59 is opened.
Set each to closed. When the timer times out, it decrements the counter COX and
If COX is not 0, repeat the above operation.

In other words, every predetermined time set in the timer,
The solenoid valves 58 and 59 are repeatedly opened, closed, and closed and opened. Therefore, since positive and negative pressures are alternately applied to the secondary side of the fluid isolator AGA, and since the primary side of the fluid isolator AGA is at atmospheric pressure, the plates 84 and 85 are connected to the housing 8.
As a result, a large amount of fluid flows in and out of the flow path on the secondary side of the AGA, and the fluid inside gradually changes from air to helium gas. Changes to

Therefore, at normal room temperature, the balloon pump 60
Even if the tube B is attached to the main body of the drive device, air can be removed from the secondary side of the fluid isolator AGA with a simple switch operation.

In the above embodiment, the fluid isolator
In order to remove air from the secondary side of the AGA,
A solenoid valve 57 is provided on the next side, and the solenoid valve 57 is synchronized with the solenoid valves 52 and 55 of the pneumatic control mechanism.
If 8 and 59 are controlled to open and close, the solenoid valve 57 is not necessary. The operation timing in that case is shown in FIG. That is, by opening the solenoid valve 52, the AGA 1
The solenoid valve 58 is opened at the timing to apply positive pressure to the next side to drive the plates 84 and 85 to the secondary side, and the solenoid valve 59 is opened at the timing to apply negative pressure to the primary side of the AGA. Open plate 8
4 and 85 should be driven to the secondary side of the AGA.

In addition, the remote operation board REM shown in Figure 1
and control unit CON1, control unit CON2, scope and lamp control unit SLCU, main unit side operation board MOB, remote control receiving unit SRU, and display unit DSPU shown in Fig. 4.
The structure and operation thereof may be those shown in Japanese Patent Application No. 58-213748, and the explanation thereof will be omitted here.

〔effect〕

According to the embodiment described above, a fluid such as helium gas that is safe even if it comes into direct contact with blood can be used as the gas in the gas supply means. is safer because it does not come into contact with the atmosphere.

Moreover, since the gas in the gas supply means is not supplied to the pressure adjustment means for pressure control, the gas supply means may be small. Therefore, the entire device can also be made smaller.

Furthermore, even when replacing the device, the atmosphere remaining in the tube between the medical pump driving means and the medical pump can be rapidly exhausted. Moreover, since this operation is performed automatically by simply giving an air venting instruction to the setting means, operational errors are reduced. Therefore, the possibility of blood coming into direct contact with the atmosphere is extremely low, and life safety is high.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the system configuration of one type of artificial heart and balloon pump drive device implementing the present invention. FIG. 2 is a block diagram showing the configuration of the fluid drive unit FDU of FIG. 1. FIG. 3 is a longitudinal sectional view showing the configuration of the fluid isolator AGA provided in the gas drive mechanism GDURB of FIG. 2. FIG. 4 is a block diagram showing the configuration of the electronic control unit ECU of FIG. 1. Fifth
This figure is a block diagram showing the configuration of the control unit CON3 of FIG. 4. 6a and 6b are flowcharts showing the general operation of the CPU 3 in FIG. 5. FIG. Figures 7, 8 and 9 are
FIG. 3 is a waveform diagram showing the operation timing of the device. 1... Artificial heart and balloon pump drive device (medical pump drive means), 51, 53, 54, 5
6, 57: Solenoid valve, 52: Solenoid valve (Solenoid valve for positive pressure switching), 55: Solenoid valve (Solenoid valve for negative pressure switching), 5
8: Solenoid valve (air discharge solenoid valve), 59: Solenoid valve (gas supply solenoid valve), 71: Compressor (positive pressure source), 72: Vacuum pump (negative pressure source), HTA: Helium tank, 61: Pressure reducing valve, AGA: Liquid isolator (medical pump drive means), PS1, PS2:
Pressure sensor, PS3, PS4: Pressure sensor (pressure detection means), CPU1, CPU2, CPU3: Microcomputer unit (electronic control means),
MOB: Main unit side operation board (setting means), REM:
Remote operation board (setting means), FBO: optical fiber cable, SP: speaker, 2a, 2b...
Tube, 60L, 60R...Artificial heart, 60B
...Intra-aortic balloon pump.

Claims (1)

[Scope of Claims] 1 Setting means comprising a plurality of switches and for setting a set value of a heartbeat cycle and an air purge instruction for performing air purge; a positive pressure source, the input end of which is connected to the output end of the positive pressure source; a positive pressure switching solenoid valve, a negative pressure source, a negative pressure switching solenoid valve having an input end connected to an output end of the negative pressure source and an output end connected to an output end of the positive pressure switching solenoid valve; a setting means, connected to the positive pressure switching solenoid valve and the negative pressure switching solenoid valve, the positive pressure switching solenoid valve and the negative pressure switching solenoid valve depending on the setting value set by the setting means; a pressure regulating device for controlling pressure, the output end of which is the output end of the electromagnetic valve for positive pressure switching; and a membrane that changes within a predetermined range depending on the applied pressure. an input end and an output end are separated via a medical pump driving means for driving a medical pump driven by the supply of pressure pulses, a gas supply means, an output side of the medical pump driving means and the gas a gas supply solenoid valve connected to the supply means; an air discharge solenoid valve whose input end is connected to the output side of the medical pump drive means and whose output end is open to the atmosphere or a negative pressure system; It is connected to a pressure detection means disposed at least on the output side, the setting means, a gas supply solenoid valve, an air discharge solenoid valve, and the pressure detection means, and detects the set value set by the setting means and the pressure. The opening and closing of the gas supply solenoid valve and the air discharge solenoid valve are controlled in accordance with the output signal of the means, and when an air purge instruction is received from the setting means, the opening and closing of the positive pressure switching solenoid valve and the negative pressure switching solenoid valve are controlled. The gas supply solenoid valve is opened and the air discharge solenoid valve is closed, and the gas supply solenoid valve is closed and the air discharge solenoid valve is open. gas control electronic control means for controlling the opening and closing of a supply solenoid valve and an air discharge solenoid valve; an input end of the medical pump drive means is connected to an output end of the pressure control device for pressure control; A medical pump driving device, comprising: a pressure regulating device for gas control, the output end of which means being connected to the medical pump.