JPH09173449A - Medicinal liquid micro injecter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate need of a special device, or need of large force for charging a medicinal liquid by detachably fixing an inner cylinder to a back part of a slidable gasket while maintaining liquid tightness in an outer cylinder, and controlling flow of the medicinal liquid pushed from the outer cylinder. SOLUTION: A gasket 2 and an inner cylinder 3 are detachably fixed by a screw 5, and a screw 4 and a screw 13 are gas-tightly threaded. The gasket 2 is moved forward and backward to suck a medicinal liquid into an outer cylinder 1. As the medicinal liquid is sucked, excessive air is discharged, the inner cylinder 3 is removed from the gasket 2, and a flow control means 7 and a gas cylinder 12 are installed. Gas in the gas cylinder 12 is discharged into the outer cylinder 1, so the gasket 2 is pushed by pressure. As a stop cock 8 is set in an opened condition, the medicinal liquid is pushed out of the outer cylinder 1, so it is sent through a micro-inner diameter tube 7 and injected into a living body at a constant speed. No special device is required, or no large force is needed for charging the medicinal liquid to this device.

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 capable of injecting a minute amount of drug solution such as antibiotics, anticancer agents, anesthetics, etc. for a long time. More specifically, the present invention relates to a chemical liquid microinjection device in which the entire device is disposable and has a simple structure.

[0002]

2. Description of the Related Art A syringe pump has been conventionally known as a device for injecting a minute amount of a drug solution into a living body for a long time. A syringe pump is a syringe (syringe)
The chemical liquid is injected at a predetermined flow rate by pushing the piston of No. 2 at a constant speed using a motor, which is excellent in that a minute amount can be accurately injected. However, because the device is large and heavy for patients to carry, it is used exclusively in the intensive care unit and bedside of hospitals.

On the other hand, a device called a balloon infusor has recently become popular as a microinjection device that can be carried by a patient. This equipment is special table Sho 62-501
As disclosed in Japanese Unexamined Patent Application Publication No. 333 and Japanese Unexamined Patent Publication (Kokai) No. 2-115959, a liquid medicine is injected into a balloon made of an elastic material, and the liquid medicine extruded by utilizing the contracting force of the balloon is a tube having a small inner diameter. The chemical solution can be continuously injected at a constant rate by passing through. Since the balloon infusor is compact and light and has excellent portability, it is used for injecting a small amount of liquid medicine such as antibiotics, anticancer agents, anesthetics and the like.

[0004]

As described above, the syringe pump is not suitable for carrying by the patient. Further, in the case of a balloon infusor, it is necessary to inject a drug solution into the balloon before use, and normally the drug solution collected in a syringe is filled from the injection port of the balloon. Therefore, there has been a problem that a device such as a syringe for filling the medicinal solution is always required, and a large force is required to inflate the balloon when the medicinal solution is filled.

[0005] Further, it is convenient if the drug solution is sealed in the product in advance and sterilized and packed so that it can be used immediately, but it is difficult to provide the product in such a form in the case of a balloon infusor. This is because if the balloon is left in a state in which the liquid medicine is sealed for a long period of time, the contraction force of the balloon is reduced, and accurate liquid injection may not be performed. Further, there is a problem that the balloon inflated state is greatly different between when the injection of the drug solution is started and when the injection is completed, and the injection rate changes gradually.

An object of the present invention is to provide a chemical liquid microinjection device which solves such a problem. That is,
No special equipment is needed to fill the device with the drug solution,
It provides a device that does not require much force. Another object of the present invention is to provide a device that can be sold by preliminarily enclosing a drug solution in the device and sterilizing it.

[0007]

SUMMARY OF THE INVENTION In the present invention, the above-mentioned problems are solved by using a device of a system in which a gasket of a syringe is pressurized by gas pressure. The present invention comprises the following two inventions according to the embodiments.

A first aspect of the present invention relates to a system in which a chemical solution is filled into a device and a minute amount is injected at the time of use. That is slidable while maintaining its properties, an inner cylinder that is detachably fixed to the rear part of the gasket, and a pressurized gas that can be airtightly attached to the rear end part of the outer cylinder with the inner cylinder removed from the gasket. A chemical liquid microinjection device comprising a supply means and a flow rate control means that can be liquid-tightly attached to the tip of the outer cylinder and can control the flow rate of the chemical solution pushed out from the outer cylinder within a predetermined range. is there.

A second aspect of the invention is a system in which a chemical solution is filled in the device in advance and provided in a sterilized state,
A cylindrical outer cylinder, a gasket slidable in the outer cylinder while maintaining liquid tightness, a pressurized gas supply means that can be airtightly attached to the rear end of the outer cylinder, and a liquid at the tip of the outer cylinder. It is composed of flow rate control means that can be tightly attached and can control the flow rate of the chemical solution pushed out from the outer cylinder within a predetermined range, and the chemical solution is sealed and sterilized in the space formed by the outer cylinder and the gasket. This is a chemical liquid microinjection device.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The outer cylinder, the gasket, and the inner cylinder which constitute the chemical liquid microinjection device of the present invention can basically have the same structure and material as a normal syringe. That is, the outer cylinder is made of a synthetic resin such as polypropylene, and has a long and narrow opening at its tip for inhaling or pushing out the chemical solution. The gasket is made of an elastic material such as natural rubber or synthetic rubber and is formed so that it can slide inside the outer cylinder from the front end to the rear end while maintaining close contact with the inner surface of the outer cylinder to maintain liquid tightness. ing. Usually, a lubricant such as silicone oil is applied to the gasket surface so that the gasket can move smoothly.

Further, the inner cylinder used in the first invention is made of synthetic resin such as polypropylene. The inner cylinder is first detachably fixed to the rear portion of the gasket by a screw or other locking mechanism. When inhaling the drug solution into the outer cylinder, the inner tube is operated in a fixed state, and after the inhalation of the drug solution and the pushing out of the mixed air are completed, the inner tube is removed from the gasket.

A pressurized gas supply means is airtightly attached to the rear end portion of the outer cylinder. As the pressurized gas supply means, a small cylinder filled with gas is preferable. As a gas to be used, carbon dioxide gas, nitrogen gas and the like are preferable in terms of safety and economy, but a gas that can be liquefied at a relatively low pressure can also be used. The gas pressure needs to be sufficient to move the gasket, but normally a gauge pressure of about 0.3 to 5 kg / cm ² is suitable. The amount of gas may be an amount sufficient to maintain a movable pressure until the gasket reaches the tip of the outer cylinder.

As a method of airtightly attaching the pressurized gas supply means to the outer cylinder, screwing with screws or fitting of tapered surfaces can be cited, and packing can be used if necessary. The pressurized gas supply means is provided with a mechanism that allows the gas to be released into the outer cylinder when the cock or lever is operated, or has a mechanism that automatically releases the gas when the attachment to the outer cylinder is completed. Press the gasket with the gas pressure.

The flow rate control means used in the present invention controls the injection rate of the chemical solution within a predetermined range, and a tube having a minute inner diameter has a simple structure and is capable of reliable flow rate control. It is preferable because it exists. The inner diameter of the tube must be selected according to the injection rate, but usually 1
Has a constant inner diameter in the range of 0 to 500 μm,
Those in the range of 30 to 200 μm are preferable. The length of such a thin tube is preferably 1 cm or more, and particularly preferably 3 to 30 cm. The flow rate control means is liquid-tightly attached to the tip of the outer cylinder, and causes the chemical liquid pushed out by the pressure of the gas to flow at a predetermined speed.

In the first aspect of the present invention, since the chemical liquid is sucked into the outer cylinder when the apparatus is used, the flow rate control means is first removed from the outer cylinder. Then, after inhaling the liquid medicine, it is attached to the tip of the outer cylinder. As a method of attachment, it is convenient to use a luer taper or lure lock method. On the other hand, in the second invention, since the chemical liquid is filled from the beginning, it can be provided with the flow rate control means attached. Further, the pressurized gas supply means also needs to be attached after removing the inner cylinder after inhaling the chemical solution in the first invention, but can be attached from the beginning in the second invention.

In the second aspect of the invention, the liquid medicine is enclosed in the outer cylinder and is sterilely packaged for immediate use. The sterilization packaging may be performed together with all the components attached, or the pressurized gas supply means and / or the flow rate control means may be packaged separately from the other components.

Examples of the drug solution to be injected into the living body using the device of the present invention include antibiotics, anticancer agents, anesthetics and the like. The injection speed is generally about 0.1 to 10 ml, and the injection volume per injection is about 10 to 200 ml.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically with reference to the drawings. FIG. 1 shows an embodiment of the first invention of the present invention and shows a state before use. As shown in FIG. 1A, the main body is composed of an outer cylinder 1, a gasket 2, and an inner cylinder 3, and the gasket and the inner cylinder are detachably fixed with screws 5. Further, a screw 4 is provided on the inner surface of the rear end portion of the outer cylinder 1, and the gas cylinder 12 shown in FIG.
It is formed so as to be airtightly engaged with the screw 13 provided at the mouth portion of the. Further, the flow rate control means 7 shown in (b) is composed of a minute inner diameter tube 10, a stop cock 8 and the like, and the connecting terminal 9 and the outer cylinder tip portion 6 can be liquid-tightly connected by a luer lock mechanism. ing. Reference numeral 11 is a connector for connecting a catheter or an indwelling needle necessary for injecting into a living body.

In order to inject a small amount of chemical liquid using this apparatus, first, the gasket is moved back and forth in the state shown in FIG. 1 (a) to suck the chemical liquid into the outer cylinder. At this time, it is preferable to attach a needle or a tube to the tip of the outer cylinder and inhale the drug solution through this. When the chemical liquid is inhaled, excess air is expelled and the inner cylinder 3 is removed from the gasket 2. Then, the flow rate control means 7 and the gas cylinder 12 are attached and brought into the state shown in FIG. When the gas in the gas cylinder 12 is released into the outer cylinder, the pressure pushes the gasket. When the stopcock 8 is opened, the drug solution is pushed out of the outer cylinder, passes through the minute inner diameter tube 7, and is injected into the living body at a constant rate.

Next, in the device of the second aspect of the present invention, since the chemical liquid is filled in the outer cylinder from the beginning, the operation of sucking the chemical liquid is unnecessary, and therefore the inner cylinder is also unnecessary. Since the drug solution and the device need to be sterilized, the drug solution is packed and sterilized in a state filled with the drug solution. As for the packaging, the main body, the flow rate control means and the gas cylinder can be packaged separately, or can be packaged in a state where all are connected as shown in FIG.

The results of the microinjection experiment using the actually manufactured device of the present invention will be described below. [Experimental Example] A commercially available syringe having a capacity of 50 ml was remodeled, and the apparatus of the present invention shown in FIG. 1 in which the gasket and the inner cylinder were made removable was manufactured. This was filled with distilled water, the inner cylinder was removed, and a gas cylinder filled with nitrogen gas having a gas pressure of about 0.5 kg / cm ² was attached to the rear end of the outer cylinder. Further, a minute inner diameter tube having an inner diameter of 80 μm and a length of 20 cm was attached to the tip of the outer cylinder, and the amount of water flowing out through the tube was continuously monitored for 6 hours. As a result, it was confirmed that water flowed out at a substantially constant rate of about 1.2 ml / hr from the beginning to the end, and that the device of the present invention fulfills the intended function.

[0022]

EFFECTS OF THE INVENTION By using the device of the present invention, there is no need for a dedicated instrument for filling the device with a chemical solution, and no large force is required. Therefore, anyone can easily fill the drug solution. Further, since the pressure fluctuation is small, it is possible to perform microinjection at a substantially constant rate from the beginning to the end.

Further, according to the second aspect of the invention, since the liquid medicine is filled in the device in advance, it can be immediately injected into the living body, and the operation is simple and convenient.

[Brief description of the drawings]

FIG. 1 is a sectional view or front view showing an embodiment of a chemical liquid microinjection device of the present invention. ((A) is a sectional view, (b),
((C) is a front view)

FIG. 2 is a front view showing a state where a chemical solution is injected using the chemical solution microinjection device of the present invention.

[Explanation of symbols]

 1. Outer cylinder 2. Gasket 3. Inner cylinder 4. Screw 5. Screw 6. Outer cylinder tip 7. Flow rate control means 8. Stopcock 9. Connection terminal 10. Micro inner diameter tube 11. Connector 12. Gas cylinder 13. screw

Claims (4)

[Claims] 1. A device for injecting a small amount of a drug solution into a living body, which is a cylindrical outer cylinder having a space for containing the drug solution therein, and slidable in the outer cylinder while maintaining liquid tightness. A gasket, an inner cylinder detachably fixed to the rear portion of the gasket, a pressurized gas supply means that can be airtightly attached to the rear end portion of the outer cylinder in a state where the inner cylinder is removed from the gasket, and a tip of the outer cylinder. A liquid medicine microinjection device comprising a flow rate control means that can be liquid-tightly attached to the portion and that can control the flow rate of the liquid medicine pushed out from the outer cylinder within a predetermined range. 2. An apparatus for injecting a small amount of a drug solution into a living body, comprising a cylindrical outer cylinder, a gasket slidable in the outer cylinder while maintaining liquid tightness, and a rear end portion of the outer cylinder. And a flow rate control means capable of controlling the flow rate of the chemical liquid extruded from the outer cylinder within a predetermined range, the pressurized gas supply means being airtightly attachable to the A chemical liquid microinjection device, characterized in that a chemical liquid is enclosed and sterilized in a space formed by the outer cylinder and the gasket. 3. The chemical liquid microinjection device according to claim 2, wherein the pressurized gas supply means and / or the flow rate control means is sterilized while being attached to the outer cylinder. 4. The chemical liquid microinjection device according to claim 1, 2 or 3, wherein the flow rate control means is a tube having a minute inner diameter.