JPS647789B2 - - Google Patents

Description

[Detailed description of the invention]

[Object of the Invention] (Industrial Application Field) The present invention relates to a blood pump drive device for driving blood pumps such as artificial heart pumps and intra-aortic balloon pumps, which are medical auxiliary circulation devices. (Prior Art) In order to treat diseases of the circulatory system of a living body, devices have been developed that assist the heart of the living body, for example, using an auxiliary artificial heart or a Parun pump. In this type of device, a drive device that generates pressure pulses to drive a blood pump such as an artificial heart pump or a paroon pump is disclosed in, for example, Japanese Patent Laid-Open No. 58-169460 and Japanese Patent Laid-Open No. 58-169462. Disclosed. In this type of drive device, a compressor generates positive pressure and a vacuum pump generates negative pressure, this positive pressure and negative pressure are stored in a tank, and a solenoid valve is used to alternately switch between positive and negative pressure. It generates pulses and supplies them to an artificial heart pump. (Problems to be Solved by the Invention) In conventional devices, for example, when switching the supply pressure to a blood pump from negative pressure to positive pressure, communication from the negative pressure tank to the blood pump is cut off, and blood is removed from the positive pressure tank. Open communication to the pump. When the communication from the positive pressure tank to the blood pump is opened, since negative pressure is accumulated in the blood pump, it takes time until the necessary positive pressure is supplied to the blood pump. The same applies when switching from positive pressure to negative pressure. In this way, the rising and falling waveforms of the pressure pulses supplied to the blood pump become gentle. In blood pumps that directly apply pressure to blood, such as artificial heart pumps, if the flow rate of blood flowing through the pump is low, a blood clot may form within the blood pump, posing a danger to living organisms. Therefore, in order not to reduce the flow rate of blood flowing into the blood pump, the time during which the blood pump drive device supplies positive pressure or negative pressure to the blood pump must be equal to or longer than a predetermined value. Here, when the living heart is trying to pump blood, if the pumping by the blood pump overlaps, an extra load is placed on the living heart, which may delay recovery. Therefore, the blood pump drive device normally controls pressure pulses so that the pumping of the living heart and the pumping of the blood pump do not overlap. but,
As mentioned above, the time for which the blood pump drive device supplies positive or negative pressure to the blood pump must be longer than a predetermined value, and the waveforms of the rise and fall of the pressure pulses supplied to the blood pump must be Because of the gradual flow, the time it takes for the blood pump to pump blood becomes longer, and the pumping of the living heart may overlap with the pumping of the blood pump. In particular, when an artificial heart pump and an intra-aortic paroon pump are attached to a living body at the same time,
During one beat of the living body's heart, the pumping by the artificial heart pump, the pumping by the intra-aortic Parun pump, and the pumping by the living's heart must be performed at different intervals. Therefore, in the present invention, the blood pump driving device sharpens the rise and fall of the pressure pulses supplied to the blood pump, and after ensuring a sufficient flow rate of blood flowing to the pump, the blood pump pumps blood over a period of time. The challenge is to make it shorter. [Structure of the Invention] (Means for Solving the Problem) The means taken in the present invention to solve this problem is a positive pressure source, and a positive pressure regulator whose one end is connected to the output end of the positive pressure source. a positive pressure accumulator connected to the other end of the positive pressure regulating solenoid valve, a positive pressure switching solenoid valve with one end connected to the positive pressure accumulator, a negative pressure source, one end connected to the negative pressure a negative pressure regulating solenoid valve connected to the output end of the source; a negative pressure accumulator connected to the other end of the negative pressure regulating solenoid valve; one end connected to the negative pressure accumulator, and the other end connected to the positive pressure accumulator; a negative pressure switching solenoid valve connected to the other end of the pressure switching solenoid valve; a positive pressure detection means for detecting the pressure between the positive pressure adjustment solenoid valve and the positive pressure switching solenoid valve;
Negative pressure detection means for detecting the pressure between the negative pressure adjustment solenoid valve and the negative pressure switching solenoid valve, and the positive pressure switching solenoid valve and the negative pressure switching solenoid valve are configured based on the pulsation timing of the living body. In the blood pump drive device, the blood pump drive device includes an electronic control means for controlling opening and closing by controlling the positive pressure switching solenoid valve, and drives the blood pump by a pressure pulse generated at the other end of the positive pressure switching solenoid valve, the electronic control means comprising:
a first positive pressure set value, a second positive pressure set value set higher than the first positive pressure set value, a first negative pressure set value, and a second negative pressure set value set lower than the first negative pressure set value. A negative pressure setting value is provided, and when the positive pressure switching solenoid valve is open and the negative pressure switching solenoid valve is closed, the detected pressure of the positive pressure detection means and the first positive pressure setting value are the same. The positive pressure adjusting solenoid valve is controlled so as to make the detected pressure of the negative pressure detecting means the same as the second negative pressure setting value, and When the positive pressure switching solenoid valve is closed and the negative pressure switching solenoid valve is open, the negative pressure adjusting solenoid is adjusted so that the detected pressure of the negative pressure detection means and the first negative pressure set value are the same. In addition to controlling the valve, the positive pressure adjusting solenoid valve is also controlled so that the detected pressure of the positive pressure detecting means and the second positive pressure set value are the same. (Function) According to the means of the present invention, the pressure values accumulated in the positive pressure accumulator and the negative pressure accumulator are changed when positive pressure is supplied to the blood pump and when negative pressure is supplied to the blood pump. When positive pressure is supplied, the pressure value accumulated in the negative pressure accumulator is low (negative pressure is high), and when negative pressure is supplied, the pressure value accumulated in the positive pressure accumulator is high. Therefore, the rise of the pressure pulse when switching from negative pressure to positive pressure and the fall of the pressure pulse when switching from positive pressure to negative pressure become sharp. After switching, the pressure in the pressure accumulator is adjusted to the desired pressure. (Embodiment) A preferred embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a medical device, which includes an artificial heart pump 11 as a main body of the medical device. The artificial heart pump 11 is provided with a positive pressure side system for compression and a negative pressure side system for inflation. Then, positive pressure or negative pressure is alternately supplied from the positive pressure and negative pressure side systems, and the artificial heart pump 11 is operated. The positive pressure side system includes an air pump 1 that is a positive pressure generation source, a pressure accumulator 7 that accumulates the positive pressure from the air pump 1, and a normally closed solenoid valve that is a driving on-off valve that connects the pressure accumulator 7 with an artificial heart pump 11. 4. Further, the positive pressure side system is provided with a normally closed solenoid valve 3 which is a supply on-off valve that communicates the air pump 1 with the pressure accumulator 7, and a pressure sensor that detects the positive pressure value accumulated in the pressure accumulator 7. A sensor 9 is attached. Similarly, the negative pressure side system includes a vacuum pump 2 as a negative pressure generation source, a pressure accumulator 8 that accumulates negative pressure from the vacuum pump 2, and an artificial heart pump 1
1, a normally closed solenoid valve 3 is a driving on-off valve that communicates with the vacuum pump 2, and a normally closed solenoid valve 6 is a supply on-off valve that connects the vacuum pump 2 with the pressure accumulator 8. A pressure sensor 10 is attached to detect the negative pressure value. The medical equipment described above is controlled and operated by the control device shown in FIG. The control device has a microcomputer CPU, which is connected via interfaces 12, 13, 14, 15, respectively, to a series of setpoint switches 16, pressure accumulators 7, 8.
Pressure sensors 9, 10 attached to the valve, a power transistor group 18 for operating a series of solenoid valves 3, 4, 5, 6, and a monitor 20 are connected. Here, the set value switch 16 sets a reference pressure value that defines the positive and negative pressure values stored in the pressure accumulators 7 and 8, as will be described later. At this reference pressure value, the driving solenoid valve 4 is opened and the driving solenoid valve 5 is opened.
The first set positive pressure value Pset1 is set when the valve closes.
is the second negative pressure set value Vset2 and the driving solenoid valve 4.
The second set positive pressure value Pset2 and the first negative pressure set value are set when the valve is closed and the driving solenoid valve 5 is opened.
Vset1, and each set value is second positive pressure set value Pset2≧first positive pressure value Pset1≧0mmHg≧
First negative pressure set value Vset1 ≧ Second negative pressure set value Vset2
have the following relationship. In this embodiment, the first positive pressure and negative pressure set value Pset
1, Vset1 and the first positive pressure and negative pressure set value Pset1,
The second positive pressure and negative pressure setting bodies Pset2 and Vset2 are set at increasing rates α and β with respect to Vset1. Therefore, the set value switch 16 sets the first positive pressure and negative pressure set values Pset1 and Vset1 and the increase rates α and β, and applies them to the microcomputer CPU. Then, in the microcopy computer CPU, the second positive and negative pressure set value Pset2 is automatically set as Pset2=Pset1 (1+α) Vset2=Vset1 (1+β)
Set Vset2. The microcopy computer CPU has a main flow as shown in FIG. Furthermore, it has an interrupt flow that is performed every 2 msec as shown in FIG. The following flags, memories, and counters are used in the flow.

〔Effect of the invention〕

As explained above, according to the present invention, the rise and fall of the pressure pulse supplied to the blood pump becomes sharp. Therefore, a sufficient flow rate of blood flowing into the blood pump can be ensured, reducing the possibility of thrombus formation within the blood pump. In addition, the time required to supply positive or negative pressure to the blood pump can be shortened to the bare minimum.
It is possible to prevent the pumping of the living heart from overlapping with the pumping of the blood pump. Furthermore, the artificial heart pump and the intra-aortic Parun pump should be used simultaneously, and the pumping by the artificial heart pump, the pumping by the intra-aortic Parun pump, and the pumping by the living heart should be staggered during one beat of the living body's heart. Therefore, there is no problem in attaching an artificial heart pump and an intra-aortic paroon pump to a living body at the same time.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a system of a drive device according to the present invention, FIG. 2 is a block diagram showing a control section of a drive device according to the present invention, and FIGS. 3 and 6 are changes in fluid pressure during drive according to the present invention. 4 and 5 are main flow and interrupt flow charts showing the operation of the control section. 1...Positive pressure source (positive pressure source), 2...Negative pressure source (negative pressure source), 3...Positive pressure side supply solenoid valve (positive pressure adjustment solenoid valve), 4...Positive pressure side drive solenoid Valve (solenoid valve for positive pressure switching), 5... Solenoid valve for negative pressure side drive (solenoid valve for negative pressure switching), 6... Solenoid valve for negative pressure side supply (solenoid valve for negative pressure adjustment), 7... Positive Pressure side pressure accumulator (pressure accumulator for positive pressure), 8... Negative pressure side pressure accumulator (pressure accumulator for negative pressure), 9...
...Positive pressure side pressure sensor (positive pressure detection means), 10...
Negative pressure side pressure sensor (negative pressure detection means), 11... artificial heart pump (blood pump), CPU... control means (electronic control means).

Claims (1)

[Claims] 1 A positive pressure source, one end of which is a positive pressure regulating solenoid valve connected to the output end of the positive pressure regulating solenoid valve, a positive pressure accumulator connected to the other end of the positive pressure regulating solenoid valve, one end of which is the positive pressure accumulator. a positive pressure switching solenoid valve connected to the device, a negative pressure source, a negative pressure regulating solenoid valve having one end connected to the output end of the negative pressure source, and a negative pressure regulating solenoid valve connected to the other end of the negative pressure regulating solenoid valve. a negative pressure accumulator, a negative pressure switching solenoid valve whose one end is connected to the negative pressure accumulator and whose other end is connected to the other end of the positive pressure switching solenoid valve, the positive pressure regulating solenoid valve and the positive pressure positive pressure detection means for detecting the pressure between the switching solenoid valves;
Negative pressure detection means for detecting the pressure between the negative pressure adjustment solenoid valve and the negative pressure switching solenoid valve; and electronic control means for controlling opening and closing of the positive pressure switching solenoid valve and the negative pressure switching solenoid valve. In the blood pump drive device that drives the blood pump by a pressure pulse generated at the other end of the positive pressure switching solenoid valve, the electronic control means is configured to control a first positive pressure setting value, a first positive pressure setting value, and a first positive pressure setting value. a second positive pressure set value set higher than the first negative pressure set value, and a second negative pressure set value set lower than the first negative pressure set value, the positive pressure switching When the solenoid valve is open and the negative pressure switching solenoid valve is closed, controlling the positive pressure adjusting solenoid valve so that the detected pressure of the positive pressure detection means and the first positive pressure setting value are the same; , the negative pressure adjusting solenoid valve is controlled so that the detected pressure of the negative pressure detecting means and the second negative pressure set value are the same, and the positive pressure switching solenoid valve is closed and the negative pressure switching is performed. When the solenoid valve is open, the negative pressure adjusting solenoid valve is controlled so that the detected pressure of the negative pressure detecting means and the first negative pressure set value are the same, and the detected pressure of the positive pressure detecting means is A blood pump drive device that controls the positive pressure regulating solenoid valve so that the positive pressure setting value and the second positive pressure set value are the same.