EP0749330A1

EP0749330A1 - Micro-infusion system

Info

Publication number: EP0749330A1
Application number: EP95943176A
Authority: EP
Inventors: Volker Prof. Dr. Lang
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-01-07
Filing date: 1995-12-21
Publication date: 1996-12-27
Also published as: DE19548537A1; WO1996020744A1

Abstract

The invention relates to a micro-infusion system particularly suitable for intravenous and subcutaneous infusion therapy, in which there is a micro-metering device (56) having at least one capillary (62, 66), where the micro-metering device (56) consists at least of a flat base plate (55) in which the capillary (62, 66) preferably takes the form of a stamped longitudinal groove and a flat cover plate.

Description

Micro infusion system

The invention relates to a microinfusion system according to the preamble of claim 1.

Today, almost exclusively expensive, complicated, heavy and bulky, electrically operated infusion pumps with complex alarm devices are used for precise intravenous and subcutaneous infusion therapy. To keep intravenous access open, especially venous catheters e.g. during transport in the hospital to small surgical interventions or special examinations such as X-ray! agnostics, nuclear medicine, metabolism, NMR spectroscopy, etc. Measures but also for postoperative pain therapy, especially that controlled by the patient, during transport by ambulance and last but not least for outpatient pain and infusion therapy at home, other, simpler infusion systems would be desirable. These systems should be simple and safe to operate, inexpensive, lightweight and small in size, should have a largely maintenance-free drive and, however, a precise i.v. Infusion therapy possible.

Infusion systems with a development in the right direction are, for example, the already available, light-weight, easier-to-use, largely maintenance-free special spring-driven infusion syringe pumps, which in combination with fixed flow rates connected by hoses. limiters are supplied for certain flow volumes per unit of time.

Problems that still exist are:

1. the flow restrictors, which are difficult to manufacture as microlumen tubes or drawn glass microcapillaries, exactly in series with the required small tolerances and can therefore only be offered at a very high price;

2. the metering inaccuracies of these flow restrictors when the viscosity of the infusion solutions changes not only as a result of additives, but above all as a function of the temperature;

3. the still too large dead space volume of these tubes with their connectors, especially if the smallest infusion volume per unit of time, e.g. should be applied for pain therapy;

4. a not possible quick, uncomplicated change of the infusion rate if necessary;

5. too long preparation times when filling the voluminous infusion lines with their connectors, filters and adapters without air bubbles, especially when using flow restrictors (microlumen tubes, capillaries) for very low infusion speeds;

6. Too large, heavy infusion pumps and infusion systems that are too cumbersome to use. The object of the invention is to develop a generic micro-infusion system in such a way that an exactly metering microdosing device, which can be produced inexpensively, is available. According to the invention, this object is achieved by means of a generic microinfusion system which additionally has the characterizing features of the main claim.

Further advantageous developments of the solution according to the invention and its advantageous production result from the subclaims following the main claim.

Further details and advantages of the invention are explained in more detail with reference to exemplary embodiments shown in the drawing. Show it:

Fig. 1: a perspective view of the invention

Microdosing device with a dosing capillary and integrated particle bacterial filter at the inlet nozzle.

Fig. 2: a longitudinal section of Fig. 1 (sectional plane I ... I)

3: a longitudinal section of the microdosing device with a dosing capillary and 2 hose connections.

4 shows a longitudinal section through a male, dead space-minimizing special Luer lock connector flanged to the capillary metering piece, which is connected to a female Luer lock connector.

5: Longitudinal section through a microdosing device with two hose connections and integrated particle filter, five different dosing capillaries in the dispenser. zial capillary metering piece and integrated slide valve (section plane: flat surface of the base plate 35 of the capillary metering piece).

6 is a perspective view of the invention

Microdosing device with a dosing capillary and integrated and connected upstream an infusion solution temperature device and a microparticle bacteria filter.

FIG. 7: a longitudinal section of FIG. 6 (section plane II..II)

8 shows a longitudinal section of the modified microdosing device from FIG. 6 with hose adapters attached on both sides.

9: schematically, the microdosing device according to FIGS. 6 and 7 is installed in a commercially available microinfusion system and fixed on the patient's skin for temperature control.

10: an exploded view of the microinfusion system with an integrated microdosing device, supplemented with a manual bolus application device, and either a spring-loaded medication reservoir in syringe form, or a hose adapter plate for connection e.g. an external, large medication container.

1 shows, assembled, in perspective a microdosing device. It consists of a capillary metering piece 1 which, via a connecting part 2 with a male Luer connector 4 with its locking thread 7 and Luer connection cone 5 is connected with a central bore 6. By means of a connecting part 3, the capillary metering piece 1 is connected via the cylindrical housing 8, which contains a particle bacterial filter 12, to a female Luer connector 9, its inner luer cone 10 and a locking element 11.

2 shows a longitudinal section (section plane I ... I) of FIG. 1. Clearly, in the male Luer connector 4, one sees the Luer connecting cone 5 with its central bore 6, which extends as far as the outlet 17 of the capillary metering piece 1 enough. This is formed from the assembled base plate 13 and the cover plate 14. The dosing capillary formed between the two plates is indicated by the dashed line 15. This metering capillary is connected to the capillary inlet 16 and via the particle bacterial filter 12 to the Luer inner cone 10 of the female Luer connector 9.

3 shows in longitudinal section the capillary metering piece 1 with the two flanged-on identical hose connectors 18, 20 with their glued-in connecting hoses 19, 21.

4 shows in longitudinal section flanged to the capillary adapter 1 the male, dead space-minimizing special luer lock connector 22 connected to a female luer lock connector 23 with a connected tube 24. As with any conventional luer connector, the inner cone 25 of the female connector 23 also seals here with the outer cone 26 of the male connector 22. As usual, locking via the Luer lock locking elements 11 and 7 is used to secure the connection.

As you can clearly see, the inaccuracy of the male and female connector results in a dome-shaped ger dead space 27, which, however, is bridged and switched off by the elastic tube (tube piece) 28. However, since this tube is located in a central bore 29 of the luer cone which tapers conically in depth, when it is connected through the bottom 30 of the female luer connector 22 it is pushed sealingly into the bore in the direction of the arrow, but only so with considerable pressure. This causes the additional formation of a sealing bead 31 on the bottom 30 of the female Luer connector 23.

5 shows in a longitudinal section, the plane of which runs along the flat surface of the base plate 35 of the capillary metering piece, this plate with an embossed distributor channel 34 for five connected metering channels 36 of different widths and depths (covered by the cover plate they become metering capillaries). In this section you can also clearly see the inlet connector 32 flanged to this base plate with an integrated particle filter and its connecting hose 33 and the flanged outlet connector 38 with the transverse bore 37 (closed at one end), into which the ends of the five metering troughs 36 open and the is closed by a tightly fitted valve slide 40 with actuating button 41. By pulling out the actuation button 41 in the direction of the arrow, one, two or up to five metering troughs (capillaries) 36 can be connected to the outlet connection with hose 39 via the bore 37 which is released.

6 to 8 show further exemplary embodiments of the micro-metering device with which metering errors due to changes in the viscosity of infusion solutions as a function of the temperature can be largely eliminated. As is known, a change in the temperature of the infusion solution from 20 "C by + 1 ^β C already causes a flow change by about -t-2.5% and a temperature of -1 ° C, a flow reduction of about 2.5%. In practice, this results in very large errors, often up to 25%.

6 shows in perspective and FIG. 7 in section an exemplary embodiment of a thermostatic microdosing capillary 46 designed as a structural unit with a small liquid reservoir 43 connected upstream. This unit is between the male Luer lock connector 4 with its adapter piece 2 and the female one Luer lock connector 10 (with built-in filter 12) and its adapter piece 3 are arranged. This unit consists of the guader-shaped base plate 42 with the disc-shaped extension 48, as well as the guader-shaped cover plate 44. Grooves and a depression are embossed in the flat surface of the base plate, which are inserted into the inlet channel 45 by the cover plate 44 which is sealingly applied. the subsequent small liquid reservoir 43 and then the microdosing capillary 46 are converted. The disc-shaped extension 48 is applied to the patient's skin with an adhesive ring for heat transfer. The plastic cover disk 47 prevents heat from being released to the environment.

8 shows an embodiment of the thermostatic microdosing capillary described above with an upstream reservoir provided with low-dead space hose connections for direct, fixed insertion into a microinfusion hose system.

9 shows an example of a schematic drawing of the arrangement of a microinfusion system, for example for outpatient pain therapy on the patient. The spring-driven infusion pump carried on a belt with an inserted infusion bag 49 is connected via a hose line 50 to a combined particle-bacteria ventilation filter 51. This the microdosing capillary with a reservoir according to FIG. 8, which is thermally coupled with an adhesive ring on the evenly warm skin of the patient (“human thermostat”), is arranged. Here the infusion solution is heated exactly and thus receives a constant, certain viscosity, which in turn is a prerequisite for a precisely defined flow through the metering capillary. From here, the infusion solution passes percutaneously via a (known) special needle 53 into an (known) infusion port 54 implanted in the patient's tissue, which is in communication with a large blood vessel of the patient.

Fig. 10 shows the new microinfusion system in supervision as an exploded view. Here, the entire infusion system from Fig. 9, which is also equipped with a bolus application device, is integrated in one unit. The bottom plate 55 with its integrated microdosing device 56 (drawn transparently and identified by a border drawn in bold) is glued with its flat underside onto the patient's skin. On its upper side, it carries the bacteria particle filter 61 provided with a sealing edge over a circular recess 59, which is connected to the distribution channel 60 of the microdosing device 56, as a cover. The distribution channel 60 feeds four dosing capillaries 62, shown in dashed lines, which enter a transverse bore 63 mouth, which can be partially or completely closed by a tightly fitting valve slide 64 if desired (see also FIG. 5) and which is additionally connected to the outlet channel 65. The meandering metering capillary 66 extending from the distributor channel 60 supplies the bolus balloon with the outlet valve 68 shown through the inlet channel 67. Under manual pressure, exerted via the small, liquid-filled handball 69 with the connecting tube 70, which is in the channel 71 is glued in, can the bolus balloon 68 are pressurized and emptied into the outlet channel 72 and the downstream channel 65 (connection for injection needle). By placing the transparent medicament reservoir 57 (in the direction of the arrow) on the surface of the base plate 55 with an integrated microdosing device 56 and a liquid-tight connection to it, the channels 67, 71, 72 and 65 become liquid-carrying channels. The particle bacterial filter 61 now receives medicament solution from the reservoir 75, which is under constant pressure by the piston 73 of the spiral spring 74, via the outlet channel 76. The elastic piercing closure is used to refill with a medication

77. If the infusion hose adapter plate 58 (with the hose connections

78, 79 and the recess 80 for bolus balloon 68 with connections) are connected to the base plate 55 with their integrated microdosing device 56, then an infusion of larger quantities of medication is also possible from external special containers under pressure (possibly also gravity) .

The function of the microdosing device and its various modifications can be described with reference to FIGS. 1 to 9 as follows. The sterile packaged device, for example according to FIG. 1, with a dosing capillary can be easily manufactured with different fixed flow volumes for aqueous infusion solutions in the range from 0.5 to 150 ml / hour and is used primarily for outpatient infusion therapy, in which the simplest to use Safe, lightweight, inexpensive, but nevertheless precisely working infusion systems are desirable, especially in combination with spring-driven infusion syringe pumps. After selecting the microdosing device with the appropriate, printed flow volume per hour, it is effortless thanks to its double-sided standard Luer connectors, to be connected on the inlet side to the spring-driven infusion syringe pump, on the outlet side to any commercially available infusion hose system. The particle filter integrated in the inlet side ensures an undisturbed capillary function by stopping microparticles introduced into the infusion solution, possibly through the addition of medication. However, if the microdosing device is to be integrated into a special infusion set, for example by the manufacturer, then an embodiment with adapters on both sides for direct gluing of the tubes, see FIG. 3, will be useful, not only avoiding unnecessary costs, but also above all, the emergence of larger dead spaces, such as connections using Luer connectors. This may be of great clinical importance when infusing small volumes per unit of time. FIG. 4 shows a special embodiment of a male Luer lock connector at the outlet end of the capillary metering piece 1, which enables a connection with a female Normluer lock connector that has very little dead space by virtue of the fact that the dead space 27 of more than 30 that always arises due to inaccurate fitting of commercial Luer connectors -50 ul is reduced to values of approximately 1-2 ul. This is achieved by means of an elastic tube or piece of tubing 28 made of soft PVC or silicone rubber, which is snugly fitted into the central bore 29, which tapers slightly in depth, and can be displaced in the direction of the arrow. This piece of tubing 28 projects a few millimeters above the standard cone 25 of the male connector 22. When connecting to the female Luer connector 23, which requires a certain amount of force, the pressure exerted on the bottom 30 of the female connector 23 on the end of the hose piece 28 results in the hose piece being pushed into the above-mentioned one conical bore 29, sealing in the same and at the same time forming a sealing bead 31 on the bottom 30 of the female Luer connector. Is used in the Mi shown in Fig. 1

SPARE BLADE (RULE 26) Krodosiervorrichtung the Normluerkonnektor 4 replaced by the special connector 22 and the connection is made with the female Normluerkonnektor 9 via just such a special connector 22 then there is little dead space despite the advantage of interchangeability, as in the embodiment shown in FIG. 3.

In Fig. 5 an embodiment of the microdosing device is shown in section, with which the initially mentioned problems of flow restrictors with microlumen tubes in combination with special spring-driven syringe pumps can all be solved simply and inexpensively.

The infusion solution dispensed by the syringe pump under constant pressure flows through hose 33, or a female standard connector arranged there, the inlet connector 32 flanged to the base plate 35 with an integrated particle filter and from there into the liquid distributor 34, into the exactly flat surface shown the bottom plate 35 is embossed. From the distributor 34, the liquid can flow through the differently wide and deep precision metering troughs 36 (covered by the cover plate, capillaries) into the cut-open transverse bore 37 of the flanged outlet connector 38 when the in the the valve slide valve 40 fits tightly and slidably, this bore connected to the outlet connection with hose 39 by pulling out the button 41 in the direction of the arrow. By pulling out to different extents, the thin precision trough shown on the left in the picture can be connected to the precision troughs arranged to the right of it according to increasing cross section. The following problems can additionally be solved with this embodiment of the microdosing device: Different infusion speeds can be set by pulling the valve slide 40 out differently without having to carry out conversion measures.

Even when using very low infusion speeds, there are no long preparation times when filling connectors, filters and adapters without air bubbles, since filters are integrated in the metering device, a dead space-free connection is realized and, above all, a high flow rate due to the integrated slide valve, by switching on the Capillaries arranged in the bypass can be adjusted when the infusion system is filled with infusion solution.

The function of FIGS. 6 to 9 has already been sufficiently explained on the basis of the preceding description.

The complete, lightweight microinfusion device of small size, shown in FIG. 10 and composed of parts 55, 56 and 57, is supplied in sterile packaging. For the subcutaneous infusion, or infusion via an implanted port, a short, special, hollow injection needle, which can be inserted directly into the outlet channel 65, is provided. A short connecting tube with a terminal winged hollow needle is used for intravenous medication administration, which is firmly inserted and locked in channel 65. Before use on the patient, the individually required medicament solution is filled into the transparent reservoir 75 in a sterile manner with the aid of a syringe via the elastic piercing closure 77. By pulling out the valve slide 64, the small-lumen channels and capillaries of the microdosing device and the bolus application device, as well as their

REPLACEMENT SADDLE (RULE 26) Balloon with Elnwegeventil 68, vented and quickly filled with solution. Now a protective film is removed from the underside of the base plate from its adhesive film, the hollow needle is inserted into a vein or subcutaneously, connected to the microinfusion device and fixed to the patient's skin. If the microdosing device is used in the context of a patient-controlled pain therapy, for example, the patient can add a pain reliever in addition to the continuous supply of pain reliever (if necessary, however, limited in time by the meandering capillary 65 filling speed of the bolus balloon with outlet valve 68). Apply by brief manual compression of the handball 69.

Example for the production of a microdosing device:

As already mentioned in the introduction, the high price for the difficult to manufacture microlumen tubes for single use, which are used as dosing elements, is still the reason for the wide clinical use of these simple, described infusion systems. In the inventive metering device presented, the capillary metering piece 1, which corresponds in function to approximately a microlumen tube, is constructed from two halves pressed onto one another, the base plate 13 and the cover plate 14 (see FIG. 1). This enables inexpensive, simple, precise and safe production of large series in the following ways:

Made of soft sheet metal e.g. Brass, copper, nickel silver etc. Possibly provided with a corrosion-resistant surface, small plates with dumbbell-shaped ends are punched out as blanks. These blanks are then used in a fine embossing process with a precisely planed stamp

ERS.ATZ3LATT RULE 26 panels with exactly surface-embossed surface. With a stamp that also has one or more parallel, possibly interconnected, micro strips on its precisely planed surface, the base plates with their metering troughs and possibly distributors are created during fine stamping. For the production of extremely fine metering troughs, it is usually advisable to insert them into the surface of the base plate by means of a cutting tool that is precisely guided on the precisely flat surface of the workpiece, or to glue a tube with a microchannel into the groove. If tolerances of the inner diameter of +/- 10% and more are allowed, the microchannel tubes will predominantly, as used, be glass capillaries. However, if the smallest tolerances are desired, then these tubes with microchannels are reduced in their internal dimensions in a process from available drawn metal tubes by means of individual, controlled, electro-galvanic inner coating in such a way that the desired flow resistances result therefrom. The base and cover plates are now pressed together, possibly additionally glued or welded together. These finished capillary metering pieces are now provided on both sides directly with glued-in connecting hoses or, according to known processes, with the connectors made of plastic by injection molding in a gas-tight and liquid-tight manner.

Claims

Microinfusion system patent claims

1. Microinfusion system with particular suitability for intravenous and subcutaneous infusion therapy,

characterized,

that it comprises a microdosing device which has at least one capillary, the microdosing device essentially consisting of a flat base plate, in which the capillary is designed as a preferably embossed longitudinal groove, and a flat cover plate covering it.

2. Microinfusion system according to claim 1, characterized in that the ends of the base and cover plates of the microdosing device are dumbbell-shaped.

3. Microinfusion system according to claim 1 or 2, characterized in that the base and cover plates of the microdosing device are made of metal, silicon, glass or ceramic consist.

4. Microinfusion system according to one of claims 1 to 3, characterized in that the base plate of the microdosing device can be produced from a metal blank by fine embossing (fine pressing) in one work process with an exactly flat surface and an exactly defined longitudinal groove .

5. Microinfusion system according to one of claims 1 to 4, characterized in that the base and cover plates of the microdosing device can each be provided with a precisely flat surface from a metal blank by fine embossing.

6. Microinfusion system according to one of the preceding claims, characterized in that a precision groove (straight or meandering) can be introduced into the exactly flat surface of the base plate by fine grinding, fine planing, electrical erosion, etching technology or laser engraving.

7. Microinfusion system according to one of the preceding claims, characterized in that one or more dosing grooves can be impressed into the precisely flat base plate, into which even the finest hollow glass fibers can be glued in order to achieve the lowest infusion speeds.

8. Microinfusion system according to one of the preceding claims, characterized in that the exactly flat surfaces of the base and cover plates of the microdosing device are covered with a non-corrosive surface, preferably made of gold.

9. Microinfusion system according to one of the preceding claims, characterized in that the exactly flat surface of the base plate is preferably covered with a very thin layer, preferably a hot-melt adhesive.

10. Microinfusion system according to one of the preceding claims, characterized in that microchannel tubes are formed in the microdosing device, which can be produced using thin metal tubes, the lumens of which are electro-galvanically reduced to the desired inner diameter by internal coating.

11. Microinfusion system according to one of the preceding claims, characterized in that the microchannel tubes can be flowed through under pressure during the electrogalvanic inner coating of the tubes with electroplating solution and measurements of the drop time, the pressure drop and electrical resistance changes can be carried out for intermittent control of the flow resistance.

12. Microinfusion system according to one of the preceding claims, characterized in that the microdosing device can be produced by pressing together and, if necessary, additionally welding or gluing the base and cover plates.

13. Microinfusion system according to one of the preceding claims, characterized in that connectors made of plastic can be attached to the dumbbell-shaped ends (which are provided with central longitudinal bends and known devices for inserting a connecting tube or standard Luerlock connecting elements .

14. Microinfusion system according to one of the preceding claims, characterized in that, in addition to the microdosing device, it contains a manual bolus application device, a medication reservoir, special connecting elements, and particle bacterial filters or only parts thereof.

15. Microinfusion system according to one of the preceding claims, characterized in that the microdosing device can be thermostatized in that the dosing capillaries and the optionally upstream liquid reservoir are arranged integrated on a thermally well-conducting substrate.

16. Microinfusion system according to one of the preceding claims, characterized in that the thermostatization can be carried out via a heat-conducting element that can be applied and fixed to the patient's uniformly warm skin, especially in the area of the stomach, chest or back.

17. Microinfusion system according to one of the preceding claims, characterized in that it comprises a thermostatable capillary dosing device with an upstream liquid reservoir, the liquid reservoir having a volume in a range of 0.01 to 1 ml and in the form of a extended and / or expanded feed channel for the dosing capillary is formed.

18. Microinfusion system according to one of the preceding claims, characterized in that the thermostatable capillary dosing device with an upstream liquid reservoir is separated from one another in a housing housed and connected to each other, for example via a hose.

19. Microinfusion system according to one of the preceding claims, characterized in that a particle and / or bacteria filter is installed in the reservoir and the Luer connector upstream of the capillary.

20. Microinfusion system according to one of the preceding claims, characterized in that in a Luerlock connection cone of a male Luerlock connector at an outlet of the microdosing device there is a central longitudinal bore which narrows conically in depth and that in An elastically deformable piece of hose (plastic tube) is slidably inserted into this hole, which serves as a length compensation sealing element for the dead space connection of commercially available, not very precise female Luerlock connectors.

21. Microinfusion system according to one of the preceding claims, characterized in that the microdosing device allows the selection of different infusion speeds by arranging two or more capillary dosing devices (with different flow volumes) in a changing device (for example slide or drum). ¬ th also allows for an ongoing infusion.

22. Microinfusion system according to one of the preceding claims, characterized in that several parallel longitudinal grooves (grooves) of different widths and depths are embossed on the base plate of the microdosing device, which are also at their inlet end or at their inlet and outlet end has an embossed transverse channel with

REPLACEMENT6LAT(RULE26) are connected to each other.

23. Microinfusion system according to one of the preceding claims, characterized in that the microdosing device has a connector with an integrated particle bacterial filter at the inlet for a hose or Luer connector and at the outlet a connector for a Luer or hose connection is additionally provided with a transverse bore that is permanently closed on one side, which firstly serves as a common connecting channel for the ends of the capillaries with the foreign channel and secondly, through an inserted elastic, sealing, manually displaceable rod, becomes a slide valve that is used to switch on or off If necessary, switch off the other capillaries required to obtain the desired flow of infusion solution.

2. Microinfusion system according to one of the preceding claims, characterized in that the bolus application device consists of an elastic hollow body (as a bolus reservoir) with an inlet port and an outlet port with an integrated one-way valve (duckbill valve), which can be manually compressed from the outside and thereby can be emptied.

25. Microinfusion system according to one of the preceding claims, characterized in that the bolus application device is installed in a sealed container which can be placed under excess pressure by squeezing a hand balloon (filled with liquid or gas) in order to squeeze out the hollow body to be able to.

26. Microinfusion system according to one of the preceding claims ehe, characterized in that it has a sandwich construction consisting of a base plate made of plastic, in which the microdosing device, bolus application device, bacterial particle filter and their connecting elements are integrated and an attached medication reservoir or a hose under filter pressure adapter plate is assembled.

27. Microinfusion system according to one of the preceding claims, characterized by T, TT, Y cross and longitudinal connectors for inserting the microdosing device into an infusion tube system, the different types of tube connectors each consisting of two embossed halves are joined together, a flat cover plate and a flat base plate, into which, depending on the desired connector, a T, Y or, for example, a cross-shaped groove are embossed.