JPH09262290A - Infusion device for liquid medicine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the device reduced in size and weight for excellent portability, structured at low cost, and designed to stably discharge a liquid medicine, by using a windup flat spiral spring as a power source for a rotary drum for fixing the tube end oppositely facing the discharging port of a liquid medicine tube. SOLUTION: The infusion device is structured so that, while a tube filled with a liquid medicine is wound by a winding means, the liquid medicine is squeezed out from the discharging port. The winding means of the device is constituted of a rotary drum 36 which fixes a base 51 and a tube end 31a oppositely facing a discharging port 31b for the liquid medicine tube and which is axially supported freely rotatably, driving means using a flat spiral spring as a driving power source, and a flattening means 34 which is a disposed between the rotary drum 36 and the liquid medicine tube and which flattens the tube barrel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drug solution injector, which is compact and lightweight for injecting a drug solution filled in a drug solution tube into epidural, arteriovenous blood vessel, subcutaneous, muscle, various organs and the like. Therefore, the present invention can be configured to be portable and can be used by arbitrarily setting the amount of liquid injection, the injection period, the injection time interval, etc. Therefore, the present invention relates to a technique which is particularly applicable to a liquid injection pump. Is.

[0002]

2. Description of the Related Art Conventionally, a drug injection device has been proposed for performing continuous microinjection of narcotics containing morphine hydrochloride for the purpose of pain relief, anticancer agents for cancer treatment, antibiotics and the like. According to these chemical liquid injectors, an electric pump using a power source such as a motor with electricity as an energy source is used, such as a battery-driven small syringe pump or a peristaltic pump.

According to such an electric pump, it is possible to appropriately control so as to obtain an arbitrary infusion amount by using an electric circuit, a control circuit by a microprocessor, etc., and therefore, fine drug administration according to the condition of the patient. There is an advantage that management becomes feasible.

On the other hand, there is known a liquid injector using a balloon made of an elastic material as a pump which is smaller and lighter in weight than an electric pump, can be constructed at a low price, and is easy to operate. For example, according to the disclosures of Japanese Examined Patent Publication No. 6-83725 and Japanese Patent Laid-Open No. 6-296688, there is a pump system that fills the inside of a balloon with a drug solution and injects the drug solution using the contraction force of the balloon. Proposed. Further, according to Japanese Patent Publication No. 51-117489, the bellows are compressed by utilizing the vapor pressure of a gas enclosed in a metal bellows and a case that covers the metal bellows, and a chemical solution in the bellows is discharged. A chemical injection device for injection is also proposed.

Further, according to Japanese Patent Laid-Open No. 7-509, after filling a cylindrical container with a drug solution, the drug solution is housed in a capsule and a plunger (presser) is attached, and the plunger is of a spring type. There is also proposed a device that discharges a chemical liquid by moving it with a constant load spring.

[0006]

However, according to the chemical liquid injector using the electric pump as described above, fine chemical liquid injection control is possible, but on the other hand, the mechanical pump and the power source attached to the electric pump are used to make the entire device. The external dimensions are large, and the weight is heavy, which results in poor portability. Further, it is pointed out that most of them have a structure in which an operating portion for setting the injection of the chemical liquid is integrally provided, so that the cost becomes high and the operation becomes complicated, too.

On the other hand, according to the chemical injection device using a balloon type pump which can be constructed at a low price and a pump which utilizes gas pressure, it is possible to construct a small size and a light weight, which is advantageous in portability. However, in these chemical liquid injectors, the pressure cannot be adjusted arbitrarily, and most of them control the flow rate with a single orifice (fluid resistor with fine holes), so one model has one flow rate. The drawback is that you can only set In addition, since the flow path for injecting the drug solution cannot be arbitrarily and automatically controlled to be turned on / off, only continuous microinjection can be performed, so that the drug solution can be administered according to the patient's condition. Is impossible.

According to the proposal of Japanese Patent Laid-Open No. 7-509, the plunger of a so-called syringe pump discharges the chemical liquid while moving the plunger of a spring type constant force spring. There is an advantage that it can be used even in a place where there is no power source such as a battery by easily winding. However, the force for moving the plunger gradually weakens near the end of winding, which causes a problem that stable ejection cannot be performed.

Therefore, the present invention has been made in view of the above problems, and a rotary drum for fixing a tube end portion facing a chemical liquid tube discharge port is powered by a manually wound spiral spring as a power source. An object of the present invention is to provide a chemical injection device that can be configured to be small and lightweight, has excellent portability, can be configured at low cost, and can stably discharge chemicals.

[0010]

In order to solve the above-mentioned problems and achieve the object, according to the present invention, a drug solution tube filled with a drug solution is squeezed out from the drug solution tube discharge port while being wound by a winding means. In the chemical liquid injector configured as described above, the winding means includes a base portion, a rotary drum that fixes a tube end portion facing the chemical liquid tube discharge port, and is rotatably supported by the base portion. It is characterized in that it is constituted by a drive means for rotationally driving the rotary drum and a flat means arranged between the rotary drum and the chemical liquid tube for flattening the tube body.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. First, FIG. 1 is a block diagram showing an overall configuration of a chemical liquid injection pump 1.

In this figure, the liquid injection pump can be made compact so that it can be put in the chest pocket of the patient's clothes, and the display unit 15 is directed upward so that the patient can see it at any time. In addition, the switches 18a and 18b are located on the front surface to facilitate the operation.

For this purpose, the flow rate control unit 11, the flow rate control device 21 built in the unit 11, the chemical liquid tube 31 which is attached to and detached from the flow rate control device 21 as described later, and the flow rate control unit 11 are attached. The interface cable 20 (for example, RS232 for serial interface) is connected to the provided connector C1.
It is composed of an external programming device 41 such as a notebook computer connected via a C cable.

While the flow rate control unit 11, the flow rate control device 21 and the chemical solution tube 31 are detachably attached to each other, after they are set in an integrated state by, for example, a snap fit, they are acted upon by an external force. It is constructed so that it will not come off easily. Furthermore, when integrally set, the connector C2 of the flow rate control device 21 is automatically electrically connected to the flow rate control unit 11, while the discharge port 31b of the chemical liquid tube 31 controls the flow rate. Flow path 2 provided on the device 21 side
2 is configured to be connectable.

On the other hand, a predetermined amount of the chemical liquid M is filled in the chemical liquid tube 31 in advance by a vacuum pack so that the bubbles are never mixed therein, and the bubbles are not mixed even during the operation. . The chemical solution tube 31 is transparent or translucent, has a predetermined mechanical strength, and is formed of a flexible polymer material so that the consumption state of the chemical solution can be seen from the outside.

Here, as the material of the chemical solution tube 31, polyethylene, polyurethane, polypropylene,
Examples of such materials include vinyl chloride, silicone rubber, urethane rubber, fluorine rubber, isoprene rubber, butadiene rubber, natural rubber, and the like, which are highly flexible and durable.

Next, in order to feed the chemical solution tube 31 filled with the chemical solution into the flow path 22 by squeezing it from the discharge port 31b of the chemical solution tube while winding the chemical solution tube 31, first the chemical solution tube 31.
The tube end portion 31a is fixed to the outer peripheral surface of the rotating drum 36 that constitutes the winding means using the base portion 51 as a base member. The rotating drum 36 is connected to the base 5 by the shaft 52a.
While being rotatably supported with respect to 1, the base 51 is provided with a pair of rollers 34, which are flattening means for flattening the body of the chemical liquid tube 31, so as to rotate freely. . Therefore, when the chemical liquid tube 31 is wound by the rotary drum 36 in the direction of the arrow, the body portion of the chemical liquid tube 31 is made flat by these rollers 34 so that the chemical liquid tube 31 is squeezed out from the discharge port 31b of the tube. Has been done.

A spiral spring manually wound to drive the rotary drum 36 to rotate in the direction of the arrow has one end fixed to the shaft 52a inside the rotary drum 36 and the other end rotated. A handle 52b, which is fixed to the inner peripheral surface of the moving drum and fixed to the shaft 52a, is manually rotated to tightly wind the main spring, and then a stopper 52c fixed to the side surface of the base 51. The handle 52b is prevented from returning by being locked by, and the rotating drum 36 is driven in accordance with the returning operation of the mainspring.

When integrally set as shown, the connector C2 of the flow rate control device 21 is in a state of being connected to the flow rate control unit 11, while the chemical solution tube 31 is connected to the flow rate control device 21. The tube 22 is automatically inserted and is in a communication state. The chemical solution M that has passed through the connecting pipe 22 passes through the fluid resistor 23 having a fine hole 23a (orifice), and the inner diameter of the fine hole 23a is preferably 10 to 500 μm and is configured to obtain a set flow rate with high accuracy. There is.

Thus, the orifice 23 of the fluid resistor 23
The chemical liquid M that has passed through a is turned on / off by the fluid control valve 24 that has the action of opening and closing the flow path, and is controlled to have a substantially constant flow rate. For this reason, the fluid control valve 24 is configured such that the flexible tube 25, which is a flow path, is pressed by the movable shaft 12a of the solenoid of the valve drive mechanism 12, which is a flow rate control valve provided in the flow rate control unit 11, by the flexible tube. 25 is a system in which the flow path is closed by directly crushing 25 itself as shown, but it goes without saying that other well-known valve mechanism can be used.

Therefore, when the valve drive mechanism 12 is off and the fluid control valve 24 is open, the pressure squeezed out from the chemical solution tube and the fluid resistance mainly determined by the flow path resistor 23 are constant. A flow rate of the drug solution M will be injected into the patient. In addition, by controlling the flow rate using this valve drive mechanism in a time-division manner, it is possible to obtain an arbitrary time flow rate value with the maximum time flow rate value when the flow path is opened. A suitable flow rate control is possible.

On the other hand, the flow rate control device 21 is further provided with a flow rate sensor 26 for measuring the flow rate of the chemical liquid in the downstream portion of the valve mechanism 24, and is attached to and detached from the control unit 11 via the connector C2. Connected possible. That is, as shown in FIG. 1, the pump assembly is connected to the control unit 11 so as to detect the flow rate, and is connected to the CPU 19 via the flow rate sensor driver 13 and the flow rate signal amplifier 14. Has been done. The flow sensor 26 is preferably a thermal type flow meter including a heater and a thermistor, but may be a positive displacement type flow meter, a differential pressure type flow meter, an ultrasonic flow meter, an electromagnetic flow meter, or the like.
Further, the control unit 11 is connected to the CPU 19 mounted on the mounting board by the respective elements shown in the figure. Specifically, the control unit 11 is connected to the valve drive mechanism 12 via a gate array, a driver element 105, etc. The display section 15 including an 8-segment liquid crystal display element, a memory 16 including an EPROM element capable of retaining stored contents even when the power is off, and the operation switch 17 are turned on when both are pressed at the same time. Chemical solution injection switch 18a, 1 connected with an AND circuit
8b, an external interface element 101 connected to a personal computer as an external programming device 41 via a connector C1, an alarm buzzer 102, and a replaceable dry battery 103. The overall operation of the liquid medicine injection device configured as described above is controlled by using software installed in the external programming device 41, and the liquid medicine injection amount, the injection time, and the PCA (Pat) called manual injection are required.
The information necessary for the pump operation such as ient controlled anesthesia) amount is input by a doctor or a qualified person, and the information is input through the external interface 101 of the control unit 11 using the external interface of the external programming device 41. External programming device 4 at this point
1 and the control unit 11 are separated.

The control unit 11 includes the flow control device 2
1 and the chemical solution tube 31 function as a chemical solution injection pump. Therefore, when these are combined, the operation switch 1 of the control unit 11 is operated.
When 7 is put in, the chemical solution injection is started after the priming operation according to the input pump operation information.

The flow rate control is performed by sending a signal from the CPU 19 to the valve drive mechanism 12 for flow rate control as described above. Therefore, the flow rate signal from the flow rate sensor 26 is sent to the CPU 19 through the flow rate signal amplifier 14 and monitored. This flow rate signal is fed back to the valve drive mechanism based on the difference between the flow rate from the pump and the measured value to perform on / off control, thereby performing flow rate control based on each administration mode described later. ing. Further, in the case of detecting an abnormality such that the flow rate detection cannot be executed, the flow rate sensor 26 is also used to generate an alarm from the buzzer 102.
The flow signal from is used. In addition, if the patient using the drug solution infusion pump is a terminal cancer patient and cannot tolerate severe pain by any means, in order to realize the above PCA injection that arbitrarily injects the drug solution morphine hydrochloride, the injection switch When both 18a and 18b are pressed at the same time, a preset amount of PCA, such as morphine hydrochloride, is injected into the patient, so that the patient's pain is alleviated. This kind of usage is only possible with the built-in memory 1
9 is stored in the memory 9 and is connected to an external programming device 41 so that the usage information can be read out, which is useful for preparing the next administration schedule and is used as a reference for preparing the next prescription. There is.

FIG. 2 is a flow chart showing the above-mentioned actual use state, showing a program at the time of initial setting.

In the figure, first, in step S1, a doctor or a qualified person loads or calls an administration program after the external programming device 41 such as a notebook personal computer is turned on. Then, in step S2, the interface cable 20 (for example, RS232C cable for serial interface) is connected to the main body of the control unit 11 via the connector C1.

Then, in step S3, a personal identification number corresponding to the patient chart is input from the device 41,
Check the medical condition and liquid medicine. When the content of the patient chart is displayed on the display screen of the device 41 in this way, the administration schedule is determined in step S4, and the type of drug solution,
Enter the injection amount, the injection period, the injection time interval, and the set value of the above-mentioned conditions for PCA injection when the drug solution is morphine hydrochloride, for example.

Since the control conditions for administration have been determined as described above, subsequently, in step S5, the power of the control unit 11 is turned on, the control condition data is transmitted, and stored in the RAM 16 which is a storage unit. It

Before and after this operation, the patient's prescription in which the device consisting of the drug solution tube 31 filled with the desired drug solution and the base 51 and the like is written is printed out from the printing device connected to the external programming device 41. It This completes the work of the doctor or qualified person.
It should be noted that the drug solution tube for up to 2 weeks can be prepared at the pharmacy by one prescription, and accordingly, the flow rate control device 21 is provided.

Then, in step S6, the connection pipe 22 of the flow rate control device 21 is set so as to penetrate the chemical liquid tube 31, and then set to the control unit 11 so that the valve mechanism can operate. On the other hand, the electrical connection is established by the connector C2. Further, the mainspring is brought into a state in which it can be introduced from the winding discharge port. Next, in step S7, the initial operation program is started based on the instruction from the external programming device 41, and the function check program, which will be described later, for checking the priming and the functions of the respective parts is started.

The operation with the external programming device 41 connected is completed as described above, and the process proceeds to step S8 in which the interface cable 20 is removed at the connector C1 and the injection needle 2 connected to the tip of the tube 25 is connected.
5a is put into a state in which the cap PC pre-embedded on the patient side is perforated. Then, in step S9, the automatic administration program based on the administration program set in step S4 is started. Further, when the drug solution is morphine hydrochloride for pain relief, the above program for PCA injection is started.

As described above, the patient can receive the medical treatment and pain relief, and the administration history of the apparatus is stored in the storage unit 19 in step S10 during the administration for a predetermined period. In step S11, the administration is continued until the remaining amount of the liquid medicine becomes small, and when the remaining amount becomes small, the administration ends.

FIG. 3 is a flow chart showing a specific example of the administration schedule in step S4 of FIG. In this figure, in step S20, the doctor confirms the medical condition and medical history of the patient, and in step S21, selects and determines either (a) continuous administration, (b) intermittent administration, or (c) continuous / intermittent administration pattern. Then, input from the external programming device 41. Then, step S
At 22, the flow rate setting, the administration time and time interval (H1, H2), the dose for PCA infusion, and the refractory period for prohibiting this PCA infusion are input based on the determined administration pattern. Then, in step S23, the PC
A The permission period is input, and 1 is entered in step S24.
The maximum daily dose is entered.

FIG. 4 is a flow chart showing a specific example of the initial operation program in step S7 of FIG. In the figure, when both the switches 18a and 18b are pressed at the same time in step S30, this program is started, and the liquid medicine is discharged from the liquid medicine tube 31 in the pressurized state (step S31).
The solenoid of the valve drive mechanism is turned off (step S
32) In step S33, it is determined whether or not a predetermined flow rate is detected by the flow rate sensor 26, and if there is no flow rate detection, it is determined that some abnormality has occurred, and the flow proceeds to step S37 to determine an abnormality. By setting the occurrence flag, the processing following this step is prohibited, and step S
At 38, an abnormal state is notified by continuously energizing the buzzer 102, and the process is forcibly ended at step S39.

On the other hand, when the predetermined flow rate is detected in step S33, the priming is completed by confirming the discharge of the liquid medicine from the injection needle 25a in step S34, and the valve mechanism is turned on in step S35 to prohibit the discharge. Then, the preparation for administration is completed in step S36.

FIG. 5 shows the second and subsequent administration programs, in which the administration schedule according to the flow chart shown in FIG. 3 is changed. When it is necessary to make such a change, in step S40, the doctor or qualified person uses the external programming device 4 such as a notebook computer.
After the power is turned on, the administration program is loaded or called. Then, in step S41, the interface cable 20 is connected to the main body of the control unit 11 via the connector C1.

Subsequently, in step S42, a personal identification number that matches the patient chart is input from the device 41, and the medical condition and drug solution are rechecked. In this way the device 4
The content of the patient chart is displayed on the first display screen.

Next, in step S43, the administration history stored in the storage unit 19 of the control unit is downloaded to the device 41 side via the interface cable 20 and displayed on the screen of the device 41. The doctor sees the activation administration schedule again to determine the optimal administration pattern, and again inputs the drug solution type, the injection amount, the injection period, and the injection time interval (step S44).

After that, in step S45, the power supply of the control unit 11 is turned on, the control condition data is transmitted, the data is stored in the RAM 16 which is the storage unit, and the chemical liquid cartridge 31 filled with the desired chemical liquid is filled in. The patient's prescription is printed out from a printing device connected to the external programming device 41. After that, the above steps S6 to S11 (step S46) are executed, and thereafter, steps S40 to S46 are performed until the patient is completely cured.

Next, FIG. 6 is an operation principle diagram (a) and a waveform diagram (b) when the flow rate sensor 26 provided in the flow rate control device 21 is composed of a thermal type flow meter. In the figure, the tube 25 has the same cross-sectional area S in the longitudinal direction, and a heater 26h is provided on the upstream side which is a flow path of the chemical liquid.
It is connected to the CPU 19 via. Further, a thermistor 26t for temperature detection is disposed downstream of the heater 26h by a distance L.

In the above configuration, at the time t1 with respect to the chemical solution M flowing downstream in the arrow direction at the required flow velocity,
The heater heating signal H as shown in (b) is applied to energize the heater 26h to raise the temperature of the chemical liquid. In this way, the peak value of the temperature rise is detected at time t2 by the thermistor 26t which is arranged downstream of the temperature rise by the distance L and is connected to the CPU via the flow rate signal amplifier 14. The thermistor output signal T having such a waveform is obtained.

From the above, the time difference Δt = t1-t2 is obtained by the built-in timer, the distance L is divided by the obtained time difference Δt to obtain the flow velocity of the chemical liquid, and the flow velocity V obtained by multiplying this flow velocity by the cross-sectional area S is obtained. obtain. Flow rate V thus obtained
Based on the above, administration of the administration will be divided into time divisions as described above. Next, FIG. 7 is an operation explanatory view of the drug solution tube winding mechanism configured as described above.
7A is a diagram showing an initial state before winding the mainspring, FIG. 7B is a diagram showing an initial state after winding the mainspring, and FIG. 7C is a diagram showing a state close to the end.

First, in FIG. 7A, a connecting pipe is set at the discharge port 31b of the chemical liquid tube 31, and the body portion 31d of the tube is held in a state of being sandwiched by the rollers 34, and the tube end portion 31a is held at the rotary drum. By being fixed to the outer peripheral surface of 36, the chemical liquid M is maintained in a state of having the internal pressure in the tube.

Subsequently, as shown in FIG. 7 (b), the handle 52b shown in FIG. 1 is manually rotated in the direction of the arrow to move the spring spring 33 whose end is fixed to the shaft 52a. After winding the shaft body 52a fully until there is no gap, set the handle to the stopper 5
When it is fixed at 2c, preparation for injection is completed, and as shown in FIG. 7 (c), by rotating the rotary drum 36 in the direction of the arrow, the body portion 31d is wound while being squeezed between the rollers 34. As a result, stable ejection is possible.

FIGS. 8A and 8B are plan views showing another embodiment in which the base portion is configured to move. In the figure, the same reference numerals are given to the already described configurations, and the description will be omitted to limit the description to the different configurations. The pair of rollers 34 are rotatable on the side wall formed on the main base 151. It is provided in. In addition, the base 51 is the main base 15
It is provided so as to be movable in the longitudinal direction of 1 by a guide (not shown).

In the above-described structure, when the mainspring is wound and the stopper is locked in the initial state shown in FIG. 8A, the body portion 31d is moved along with the winding operation of the rotary drum.
Is wound while being squeezed between the rollers 34, while the base portion 51 moves in the direction of the arrow by the amount corresponding to the tube winding amount.

As described above, by using the mainspring of the rotary drum as a power source, which is manually wound, a compact and lightweight structure can be obtained.
It is excellent in portability, can be configured at a low price, and can stably discharge the chemical liquid.

[0048]

As described above, according to the present invention,
The rotary drum that fixes the tube end facing the discharge port of the chemical liquid tube can be made compact and lightweight by using a manually wound spiral spring as a power source, it is excellent in portability, can be constructed at low cost, and is stable. A chemical injection device capable of discharging a chemical can be provided.

[0049]

[Brief description of drawings]

FIG. 1 is a block diagram showing a state after connection of a flow rate control device 11, a control unit 21, and a chemical liquid cartridge.

FIG. 2 is a flowchart for setting an administration schedule.

FIG. 3 is a flowchart showing a specific example of step S4 in FIG.

FIG. 4 is a flowchart of an initial operation.

FIG. 5 is a flow chart of second and subsequent administration schedule setting.

FIG. 6 is an explanatory diagram of flow rate measurement.

7A and 7B are operation explanatory views of the winding mechanism of the chemical liquid tube, in which FIG. 7A is an initial state before winding the mainspring, FIG. 7B is an initial state after winding the mainspring, and FIG. It is the figure which showed the state.

8A and 8B are plan views showing another embodiment in which the base is configured to move.

[Explanation of symbols]

 11 Flow Control Unit 12 Valve Drive Mechanism 13 Flow Sensor Driver 14 Flow Signal Amplifier 15 Display 16 Memory 17 Operation Switch 18 Chemical Injection Switch 19 CPU 20 Interface Cable 21 Flow Control Device 22 Connection Pipe 23 Fluid Resistor 24 Fluid Control Valve 25 Soft tube 26 Flow rate sensor 31 Chemical liquid tube 33 Spring spring 34 Roller (flattening means) 36 Rotating drum 41 External programming device

Claims (4)

[Claims] 1. A drug solution injector configured to squeeze a drug solution tube filled with a drug solution by a coiling device while squeezing the drug solution tube from a discharge port of the drug solution tube, wherein the coiling device includes a base portion and the drug solution tube. A rotary drum that fixes a tube end portion facing the discharge port and is rotatably supported on the base portion, a driving unit for driving the rotary drum, and an arrangement between the rotary drum and the chemical liquid tube. And a flattening means for flattening the tube body. 2. The chemical liquid injector according to claim 1, wherein the drive means uses a power spring as a power source that is manually wound. 3. A flow path connected to the chemical solution tube discharge port and having a fluid resistance means for restricting a flow rate connected at an intermediate portion, and a fluid resistance means of the fluid resistance means for interrupting the flow rate of the chemical solution in the flow path. Flow rate control means provided on the downstream side, flow rate measurement means provided on the downstream side of the flow rate control means for measuring the flow rate in the flow path, and control connected to the flow rate control means and the flow rate measurement means The liquid medicine injector according to claim 1, further comprising means. 4. The chemical solution injection according to claim 1, wherein the flattening means is provided in a main base part that guides the base part so as to be movable along the longitudinal direction. apparatus.