INJECTION INGRESS

Abstract: An injection ingress with a supply means (3) provided with a channel (10) protruding into the body tissue of a patient for supplying an injection agent to the body tissue or a blood vessel. The supply means (3) is provided at one end with an enlarged portion (5) having a reception space (9) in communication with the channel (10), said space being designed to uptake the point of a hypodermic syringe. The enlarged portion is provided with a positioning means (7) to secure the arrangement to the patient's skin (1) and with a valve member (15) through which the point of the syringe can be inserted into the reception space.

Description: INJECTION INGRESS TECHNICAL FIELD The present invention relates to an injection ingress in¬ tended for substantially permanent transplant or at least long-term implanting into the body tissue of a patient, said injection ingress comprising a means protruding into the body tissue or a blood vessel and being provided with a channel for supplying an injection agent to the body tissue. BACKGROUND OF THE INVENTION In the case of diseases requiring the repeated supply of the type of drug which is injected into the body tissue, this has previously been effected with the aid of a con¬ ventional hypodermic syringe which is simply inserted into the " body tissue at a suitable point, whereafter the contents of the syringe is emptied and the syringe then withdrawn. This method entails considerable drawbacks, particularly if the drug must be administered frequently, primarily because the risk of infection and the formation of scars can never be avoided. However, this method of injection using conventional syringe has the advantage that the quantity of agent to be injected can be accurately measured. In this connection it should also be mentioned that some ■ patients are hardly capable of effecting the necessary in- jection in conventional manner or dare not. A considerable amount of time is thus demanded on the part of nursing staff for this purpose, not to mention the discomfort and pain ' inflicted by such injections. When injecting drugs into a blood vessel on repeated occasions, a needle made of a hard material, usually metal, is normally used. This is inserted into the blood vessel and held in position by an adhesive plaster or the like adhering to the "patient' s skin. The greatest drawback with this procedure is that the needle must be frequently changed and that it causes both irrita¬ tion and direct pain. OBJECT OF THE INVENTION The object of the present invention is to achieve an injec¬ tion ingress of the type described in the introduction, which is designed to completely eliminate the drawbacks of conventional hypodermic syringes or needles without jeopar- . dizing precision in measuring' he quantity of agent to be injected. The object of the invention is thus to effect an injection ingress, the use of which does not inflict pain or other discomfort and which is designed in such a manner that the patient himself can perform the injection, even if his hand is shaky or he has impaired vision, or is even blind. SUMMARY OF THE INVENTION The basic aim of the invention is achieved by an injection ingress wherein the supply means is provided at one end with an enlarged portion having a reception space in commu- nication with the channel, said space being designed to take the point of a hypodermic syringe, wherein the enlarged portion is provided with a positioning means to secure the arrangement to the patient's skin, and wherein the enlarged portion is provided with a valve member through which the point of the syringe can be inserted into the reception space. in order to eliminate the risk of tissue damage and skin irritation, but also to reduce any problems associated with the use of the device to an absolute minimum, according to the invention the supply member is in the form of a thin, flexible tube of material compatible with the body tissue, the enlarged portion being designed to be located mostly below the surface of the skin and consisting of or provided with a surface layer or a surface treatment to facilitate its growth into the skin. These features offer the great advantage that the supply member is able to move together with the surrounding tissue and also that the enlarged portion is able to become pro- perly secured in the skin, possibly even becoming perma-. nently embedded. The object of the invention is preferably also characterised in that the tube and the enlarged portion are composed of the same material and the side wall of the tube is perfora- ted. These features offer both manufacturing advantages and the great medical advantage of increased absorption area for the injection agent in the body tissue, thus reducing the risk of tissue damage as well as improving the absorption rate for the injection agent. Additional advantages are achieved according to the inven¬ tion, if the object of the invention is given one or more of the features defined in claims 4 - 7. BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with reference to the accompanying drawings, in which Figure 1 shows a section through a portion of tissue on a patient, with a first embodiment of the invention applied, Figure 2 shows a modified embodiment of the invention in a view corresponding to Figure 1, Figure 3 shows a longitudinal cross section through the object of the invention in a first, preferred embodiment, Figure 4 shows a second embodiment of the invention in a view corresponding to Figure 3, and Figure 5 shows a third embodiment of the invention in a view corresponding to Figure 3. DESCRIPTION OF SPECIFIC EMBODIMENTS Figure 1 shows a section through the body tissue 2 and skin 1 of a patient. A first embodiment of the invention is implantated in an outer part of the body tissue. It can be seen that the invention comprises a supply means or tube 3, embedded in the body tissue 2 of the patient and having a suitable length, often 1 - 2 cm, for the purpose. This tube may, of course, terminate in a blood vessel instead. To increase the area of tissue 2 able to absorb the drug supplied from the means 3, the supply means or the tube may be perforated along the side wall. This is indicated in Figure 1 by small dots. To further improve penetration of the injection agent through the perforations in the side wall of the tube, the free end 4 may be made narrower or be entirely closed to the longitudinal inner channel through which the medicament is supplied. Figure 1 also shows that the supply means 3 is provided at the end towards the -skin 2 with an enlarged portion 5, the purpose and construction of which will be described in more detail in the following. The enlarged portion 5 is prefer¬ ably provided with a collar 6 or shoulder against which rests a disc 7 of a flexibly, or possible hard material. An attachment part 8 is provided on the outside of the disc 7, continuing from the enlarged portion 5. This part prevents the disc from becoming detached from the enlarged portion and, as will be described below, also has certain functions with respect to the valve member which is located internally in the enlarged portion, in connection with the attachment part. As implied above, a valve member is arranged in connection with the attachment part 8 and is so designed as to allow the point of a conventional hypodermic syringe to pass through it, thus allowing the point of this needle to enter a reception space in the interior of the enlarged portion 5. A narrow channel then leads from this reception space out to the supply means and the tube. It should be mentioned that the volume in this channel and the volume in the re¬ ception space should be as small as possible in order to ensure accuracy of the quantity of medicament to be injected via the object of the invention. In principle two different methods may be used to apply the device according to the invention. In the first case the valve member at the attachment member 8 is removed, thus forming an axially directed aperture through the entire device, into which a needle is inserted, the point extend- ing past the free end 4 of the tube 3. With the aid of this needle a hole is .pricked in the patient's skin and in the tissue 2 below, after which the device is pressed into the hole so that the disc 7 rests on the skin 1. The disc 7 is then secured with sticking plaster, adhesive or in some other suitable manner. When the disc 7 has been secured, the needle is withdrawn to expose the channel running axial¬ ly through the device and the valve member and attachment part 8 are then applied. The second method entails enclosing the device in a hard casing of material which will be dissolved by the body and • thus disappear. To enable insertion through the skin 1 and in into the tissue below, the casing is tubular in shape, to take the tube 3, and has a sharp point at the end. The procedure for securing the disc 7 is the same as that described above but in this case the valve member need not subsequently be fitted. Figure 3 shows a longitudinal section through the embodiment of the invention described in Figure 1. It can be seen that the enlarged portion 5 has an axially drilled bore 9 which also constitutes the reception space. A longitudinal channel 10 leads from the lower end of this bore 9 to the open end of the tube 3. It can also be seen that the enlarged portion is provided with shoulders 6 in contact with the disc 7, which in turn is held in position by the attachment part 8. In this embodiment the attachment part is in the form of a threaded nut, preferably made of metal or plastic. In the embodiment shown in Figure 3 an insert 11 is used in the enlarged portion 5. This insert is suitably made of en¬ tirely rigid material such as hard plastic, metal or the like, and must be selected ensuring that it will not be affected either by the medicament to be injected through the device or by body tissue or liquid produced thereby. The insert 11 is entirely enclosed in the enlarged portion 5 except for an annular neck 12 with external threading to correspond with the threading on the attachment part or nut 8. From the drawings it can be seen that the disc 7 has an opening into which is fitted a part 14 surrounding the in¬ sert 11, this surrounding part having a radially external defining wall which cooperates with the opening, correspond- ing in shape, in the disc 7. The disc is thus prevented from rotating in relation* to the enlarged portion 5. The sur¬ rounding part " 14 is of- course composed of the same material, inert with respect to the body, as the tube 3 and enlarged portion 5. The surface of the surrounding part 14 which co- operates with the disc 7 may be rectangular or polygon in order to achieve reliable engagement with the disc 7, pre¬ venting rotation thereof. In the embodiment shown in Figure 3 the valve member con¬ sists of a disc 15 of resilient material which is com- pressed by the nut 8 in a recess 16 in the insert 11. The disc 15 is compressed and made of a resilient material to facilitate penetration by the point of an injection needle without any permanent opening remaining in the disc when the needle has been withdrawn. The valve member will there- fore be completely self-sealing and form a perfect seal as long as it has not been penetrated too often. The disc 15 can be replaced by simply unscrewing the nut 8, removing the disc from the recess 16 in the insert 11 and replacing it by a new one. The attachment member or nut 8 is then screwed back into place. It should be pointed out that the insert 11 and the enlarged portion 5 connected therewith are prevented from rotating due to their engage¬ ment with the disc 7 and its adhesion to the skin. Figure 3 also shows that all surfaces of the device designed to be implanted in the skin or in the tissue below the skin of the patient consist of the same material as the tube 3 and enlarged portion 5. The small part 12 of the insert 11, to which the nut 8 is screwed is located outside the disc 7 and is therefore without significance insofar as contact with the body is concerned. DESCRIPTION OF MODIFIED EMBODIMENTS Figure 2 shows a modified embodiment of the invention accord ing to Figure 1. The most significant difference here is tha the longitudinal direction of the supply means or tube 3 and the enlarged portion 5 is located at an angle to the plane of the disc 7. An internal, longitudinal channel through the device according to the invention is thus also used in this embodiment, as well as a self-sealing valve in conjunction with the attachment member 8. In the embodiment according to Figure 2, the enlarged por- tion 5 with the reception space 9 is located partially out¬ side the skin 1. It is of course possible to go one step further and locate this entirely outside the skin if de¬ sired. The embodiment according to Figure 4 has certain features in common with that according to Figure 3. In this embodiment, too, an insert 17 of substantially solid material is used, such as hard plastic or metal. The insert 17 fits into a corresponding recess 18 in a tubular section 19 of the end of the enlarged portion 5 opposite to the tube 3. Between the tubular section 19 and the shoulder 6 for abutment against the disc 7 is a peripheral groove with conical sur¬ face 21, the groove expanding in axial direction away from the disc 7. The insert 17 is also provided with a corres¬ ponding conical surface 22, approximately parallel to the conical surface 21 of the groove 20. Furthermore, at the end facing away from the disc 7, the insert 17 is provided with a shallow recess to hold the actual valve member or disc 15, this also consisting of resilient material under pressure. The pressure loading is effected in this embodiment by a ring 23, slotted in axial direction, made of a permanently deformable material such as metal and having an inwardly directed portion 24 at the end facing the disc 7, the portion 24 being approximately complementary to the groove 20. When the ring 23, somewhat expanded in circumferential di¬ rection, is passed over the tubular portion 19 and there¬ after clamped by means of a tong or similar tool, the in¬ wardly directed portion 24 will be taken up in the groove 20 and will compress the material in the enlarged portion 5, thus pressing the insert 17 away from the disc 7. The in¬ sert 17 will thus exert axial pressure on the disc 15 bring¬ ing it into abutment with the inside end surface of the slotted ring 23. It can be seen from Figure 4 that the inwardly directed por- tion 24 of the ring 23 will abut against the disc 7, secur¬ ing this in position against the shoulder 6. In the embodiment according to Figure 5 the end of the en¬ larged portion 5 facing away from the disc 7 is provided with a recess surrounded by a curved wall 25 and having substantially conical bottom 26. A ring 27 is arranged radially outside the curved wall 25 to prevent radial expan¬ sion and deformation of the curved wall. This ring prefer¬ ably consists of hard plastic or metal and is provided externally with a peripheral groove for a locking ring 28 to lock the disc 7 in- relation to the ring 27. In this embodiment the valve member comprises a substantial¬ ly circular disc 15 which is pressed down into the space defined by the curved wall 25 and the conical bottom 26 of the recess in the end of the enlarged portion 5 facing away from the tube 3. This disc 15 is inserted through an opening 29 extending through both the ring 27 and the curved wall 25. The dimensions are selected so that during compression the disc 15 must be pressed to the position shown in the drawing where it is retained in compressed state, bulging slightly towards the conical bottom surface 26 and reception space 9. The material to be used for those parts of the device accord¬ ing to the invention coming into contact with body tissue or skin must be selected with great care. However, it may be mentioned that silicon material of semi-hard or rubberlike consistency has proved extremely suitable for both the en- larged portion 5 and the tube 3. Obviously, due to its slim dimensions (external diameter in the order of 0.5 - 1 mm and inner diameter in the order of 0.1 - 0.5 mm), the tube will be extremely flexible and will therefore follow any movement in the body tissue without causing irritation or discomfort. Similarly the enlarged portion 5 will not be completely rigid, but deformable, so that it too can adjust to movements in the skin and tissue below the skin. The material for the disc 7 should of course be substantially rigid and stable in shape. However, it should not be so hard as to cause discomfort to the user. Naturally the disc mate¬ rial should be of a quality which will not cause allergy or skin irritation. The tube 3 has been shown in all the drawings as relatively short and approximately uniform in thickness. Obviously, the tube 3 may be considerably longer and its cross section may vary, it being thicker close to the enlarged portion 5 than at the free end 4, for instance. A tube of this design may be suitable for supplying drugs to internal organs or the like. It has been mentioned above that the side wall of the tube 3 may suitably be perforated, thus increasing the absorption area for the drug injected. Obviously an unperforated tube may also be used, and is necessary if a drug is to be accurately supplied to a specific area. As mentioned above, both the tube and the enlarged portion 5 may be made of a silicon rubber, in which case they can be manufactured in one piece by an injection moulding pro¬ cess or by joining the enlarged portion 5 to an extruded tube, the join being effected by glueing or vulcanization. It might also be possible to make the enlarged portion of different material, such as metals like titanium or certain stainless steel alloys, for instance, the tube 3 then being glued into the enlarged portion. In this case it may be advisable to make the tube 3 thicker at the joint with the enlarged portion to prevent damage in this area. Certain grades of polythene may also be used as an alterna¬ tive to the above-mentioned silicon material for the tube 3 and enlarged portion 5. The invention can be modified within the scope of the follow¬ ing claims.

Claims: C l a i m s 1. An injection ingress comprising a means (3) protruding into the body tissue (2) of a patient, said means being provided with a channel (10) for supplying an injection agent to the body tissue or to a blood vessel, w h e r e - i n the supply means (3) is provided at one end with an enlarged portion (5) having a reception space (9) in commu¬ nication with the channel (10) , said space being designed to take the point of a hypodermic syringe, wherein the en¬ larged portion is provided with a positioning means (7) to secure the arrangement to the patient's skin, and wherein the enlarged portion is provided with a valve member (15) through which the point of the syringe can be inserted into the reception space. 2. An injection ingress according to claim 1, w h e r e - i n the supply member (3) is in the form of a thin, flexib¬ le tube of material compatible with body tissue, wherein the enlarged portion (5) is designed to be located mostly below the skin (1) and consists of or is provided with a surface layer or a surface treatment to facilitate its growth into the skin. 3. An injection ingress according to claim 2, w h e r e - i n the tube (3) and the enlarged portion (5) are composed of the same material and the side wall of the tube is per¬ forated. 4. An injection ingress according to any of claims 1 - 3, w h e r e i n the longitudinal axis of the enlarged por¬ tion (5) and the tube (3) is approximately perpendicular to the positioning member (7) , which is in the shape of a disc. 5. An injection ingress according to any of claims 1 - 3, w h e r e i the longitudinal axis of the enlarged por¬ tion (5) and the tube (3) forms an acute angle to the posi¬ tioning means (7) , which is in the form of a disc. 6. An injection ingress according to any of claims 1 - 5, w h e r e i n an insert (11, 17) is arranged inside the enlarged portion (5) , said insert consisting of a hard mate¬ rial inert to influence from the injection agent or the body, and forming at least a part of the reception space (9) , the valve member (15) being replaceably secured in this insert. 7. An injection ingress according to claim 6, w h e r e ¬ i n a positioning member (8, 23) for the valve member (15) in the insert (11, 17) is provided to prevent removal of the positioning member (7) from the enlarged portion (5) .

Inventors: ARVIDSSON CARIN, ARVIDSSON, CARIN
Applicants: ARVIDSSON CARIN, ARVIDSSON, CARIN
Application year: 1986
Main classification: A61M5
IPC codes: A61M1, A61M37, A61M39