Abstract:
The disclosure relates to a connector for packaging containing medical fluids, in particular infusion or transfusion bags, including a tubular connection part for receiving a spike for the withdrawal of fluid, and having a lower opening on the packaging side and an upper opening on the connection side. A self-sealing membrane, which is pierced by the spike, is located in the connection part. The membrane has an upper, annular section leading into a lower, plate-shaped section, said annular section of the membrane surrounding the spike in a sealing manner, when the latter pierces the plate-shaped section. The membrane acts as a guide for the spike and also reseals the connector, once the spike has been removed.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 10/514,817, filed on Nov. 12, 2004, which is a U.S. national phase of International Application No. PCT/EP03/01847 filed Feb. 24, 2003, which claims priority to German Application No. 102 23 560.0, filed May 27, 2002. The entire disclosure of each of the above-identified applications is incorporated herein by reference. 
    
    
     BACKGROUND 
     The disclosure relates to a connector for packaging containing medical fluids, in particular infusion or transfusion bags, which serves to extract a fluid from the bag. Moreover, the disclosure relates to packaging for medical fluids, in particular an infusion or transfusion bag, with such a connector. 
     RELATED TECHNOLOGY 
     WO 96/23545 describes an infusion bag with an injection part and an extraction part. The injection part serves to feed a drug by means of an injection syringe. It comprises a tubular connection part, which is sealed by a protective cap designed as a break-off part. A self-sealing septum sits in the opening area of the connection part, whilst a membrane capable of being pierced is arranged in the connection part, so that the septum does not come into contact with the solution before the use of the infusion bag. The extraction part serves to extract the solution by means of a spike. The extraction part does not have a self-sealing septum, otherwise the structure is similar to that of the injection part. 
     A connector for the extraction of an infusion solution is also described in DE 197 28 775 C2. The tubular connection part of the known extraction part is sealed by a flat membrane, which is in one piece with the connection part. 
     The known extraction parts have been tried and tested in practice. A drawback, however, consists in the fact that the infusion bag is not sealed again after the spike has been withdrawn. There is therefore the risk of the infusion solution running out. This is particularly critical after the addition of cytostatic drugs. 
     A further drawback is that the connection between the spike and the extraction part is not secured against slipping out. When the bag is hanging on the stand, there is the risk of the connection of the spike arid the extraction part being separated due to unintentional tugging on the flexible-tube line. 
     There is also the drawback that the injected membrane, which seals the connection part of the extraction part, does not always withstand greater mechanical loads. Thus, it has been shown in drop tests that the membrane of individual extraction parts ruptured. 
     SUMMARY 
     The problem underlying the disclosure is to provide a connector for packages containing medical fluid, in particular infusion or transfusion bags, which reliably seals the packaging after the withdrawal of the spike. 
     Accordingly, the disclosure provides a connector for packages containing medical fluids, including a tubular connection part for receiving a spike for the extraction of the fluid, the connection part having upper and lower openings, a break-off sealing part, a self-sealing membrane that can be pierced by the spike for the extraction of the fluid and having a circular upper portion, which transforms into a dish-shaped lower portion to form a trough-shaped recess, wherein a portion of the membrane sealing surrounds the spike when the spike pierces the dish-shaped portion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The figures show the following: 
         FIG. 1  illustrates a connector designed as an extraction part for packages containing medical fluids in sectional representation, 
         FIG. 2  illustrates an infusion bag with the extraction part of  FIG. 1  and an injection part and 
         FIG. 3  illustrates the injection part of the infusion bag of  FIG. 2  in sectional representation. 
     
    
    
     DETAILED DESCRIPTION 
     The connector according to the disclosure has a self-sealing membrane, which is arranged in the connection part for accommodating the spike for the extraction of the fluid. The self-sealing membrane prevents the fluid from running out of the packaging after withdrawal of the spike. 
     It is advantageous that the self-sealing membrane has a circular portion, which transforms into a dish-shaped portion, whereby the circular portion of the membrane surrounds the spike in a sealed manner when it pierces the dish-shaped portion. 
     The special formation of the membrane with the circular and dish-shaped portion on the one hand ensures that the spike is guided reliably when it pricks the membrane and on the other hand guarantees that the membrane is again reliably sealed after withdrawal of the spike even in the presence of relatively high internal pressure in the packaging. It has been shown in tests that the special formation of the membrane is decisive for immediate re-sealing, whereby the sealing of the membrane is further enhanced with increasing pressure in the packaging. The reliable sealing can be traced back not to the volume of material, but to the special geometry of the membrane. 
     In a preferred form of embodiment of the connector, the material of the dish-shaped portion of the membrane is weakened, so that the membrane can be particularly easily pierced by the spike. The membrane is preferably pre-slit in the form of a cross. It can also be pre-slit in the form of a star or only be provided with a simple slit. 
     In a particularly preferred form of embodiment, the tubular connection part of the connector consists of a lower and an upper section, whereby the sections are fixed in a snap-in manner. The self-sealing membrane is preferably held clamped with elastic deformation of the same between the lower and upper section. Consequently, the fitting of the connector can be carried out in a straightforward manner by pressing of the individual parts. It is however also possible for the individual parts to be welded and/or glued together. 
     A further particularly preferred form of embodiment makes provision such that an outer portion, which is clamped between the two sections, follows on from the circular portion of the membrane. 
     In order to prevent the self-sealing membrane in the tubular connection piece from coming into contact with the solution contained in the infusion and transfusion bag prior to the use of the latter, a second membrane capable of being pierced is preferably arranged beneath the self-sealing membrane thereby forming an intermediate space. The second membrane is expediently a one-piece component of the tubular connection piece. 
     It has been shown in tests that the use of a membrane curved upwards or downwards instead of a flat membrane leads to an increase in drop strength. Since the second membrane is designed curved upwards or downwards, the connector according to the invention withstands relatively great mechanical loads. Apart from the increase in drop strength, there is also the advantage that the spike in the pierced position is held clamped by the curved membrane. The retention force of the spike in the withdrawal position is thus increased, as a result of which unintentional slipping out is prevented. 
     In order to secure the upper and lower part of the connection piece against radial torsion, both parts can have toothing or the like, which also ensures precise alignment of the parts during pressing together. Furthermore, the risk of damage to the two membranes is especially low during the pressing together of the individual parts. 
     The break-off sealing part of the connector, which serves as an originality seal, is preferably connected to the connection part via a circular rupture zone. 
     Since the break-off sealing part preferably has a grip part, which is designed in the manner of an arrow pointing upwards, it can immediately be recognized that the connector is an extraction part, but not an injection part. Preferably, the arrow is a recess in the grip part, which is immediately recognizable without lettering or the like being necessary. Confusion between the extraction and injection part of a package containing medical fluids can thus be avoided. 
     The lower part of the connection piece also preferably has an arrow pointing upwards, which is designed as a raised structure, preferably in a recessed grip. The upward-pointing arrow of the lower connection-piece part also permits the connector to be unequivocally assigned as the extraction part after breaking-off of the sealing part. 
     An example of an embodiment is explained in greater detail below by reference to the drawings. 
     Connector  20  designed as an extraction part for packages containing medical fluids, in particular infusion or transfusion bags, has a tubular connection part  1 , which includes a package-side lower section  2  and a connection-side upper section  3 . Tubular connection part  1  therefore has an upper and a lower opening  1   a ,  1   b . Connector  20  is an injection-moulded part made of polypropylene. 
     Lower section  2  of tubular connection part  1  has a lower cylindrical portion  4 , which transforms into an upper sleeve-shaped portion  5 . Cylindrical portion  4  of lower section  2  can be inserted into a connection socket of a film bag and can be welded or glued to the socket or be directly welded into the film bag without a socket. Cylindrical portion  4  is sealed at its upper end with a membrane  6  capable of being pierced, said membrane being a single-piece component of lower section  2 . The injected membrane is curved downwards. Alternatively, however, the membrane can also be curved upwards. 
     Upper section  3  of tubular connection part  1  is fixed in a snap-in manner on lower section  2 , whereby upper section  3  has a cylindrical portion  7  which surrounds lower section  2 . The internal wall of cylindrical portion  7  of upper section  3  has a peripheral groove  8 , into which a peripheral projection  9  on the outer wall of sleeve-shaped portion  5  of lower section  2  snaps when the two sections  2 ,  3  are pressed together. 
     A self-sealing membrane  10  made of an elastic material, which is also referred to as a septum, is held clamped with elastic deformation of the same between the lower and upper section  2 ,  3  of tubular connection part  1 . Self-sealing membrane  10  has an outer portion  11 , which is clamped between lower and upper sections  2 ,  3  of circular connection part  1 . Outer portion  11  is followed by an upper circular portion  12 , which transforms into a lower dish-shaped portion  14  thereby forming a trough-shaped recess  13  at the upper side of membrane  10 . Dish-shaped portion  14  is pre-slit in the form of a cross or a star in centre  15 , so that the elastic material is weakened, but is not severed. 
     Upper section  3  of tubular connection part  1  is followed, via a circular rupture zone  31 , by a cap-shaped sealing part  16 , which seals upper opening  1   a  of connection part  1 . Sealing part  16  transforms into a flat grip part  17 , which is provided with a recess  18  in the shape of an arrow  19  pointing upwards. It can immediately be recognized from the direction of arrow  19  that connector  20  is not injection part  40 , but rather the extraction part. 
     The side view of connector  20  of  FIG. 1  is shown in  FIG. 2 .  FIG. 2  shows an infusion bag  21  filled with infusion solution, which has connector  24  for the extraction of the infusion solution and a further connector  40  for the injection of a solution into infusion bag  21 . 
     On the outer wall of cylindrical portion  7  of upper section  3 , tubular connection part  1  of connector  20  has two recessed grips  21  lying opposite one another, which are each formed by projecting webs  22  which are arranged at a distance from one another. A further arrow  23 , which also points upwards in order to identify connector  20  as the extraction part, is formed as a raised structure on the outer wall of cylindrical portion  7  between webs  22 . 
     Infusion bag  21  comprises two film layers  24 , which are welded together at lower and upper edge  25 ,  26  and also at longitudinal edges  27 ,  28 . Two connections sockets  29 ,  30  are welded into upper edge  25  of the infusion bag. The tubular connection pieces of injection and extraction part  40 ,  20  are inserted into connection sockets  29 ,  30  and connected with the sockets during sterilization. The tubular connection pieces of the originality seals can however also be molded onto an insert that is round or designed in the manner of a boat, said insert being welded in between the two film layers. 
       FIG. 3  shows injection part  40  of film bag  21  in a sectional representation. Injection part  40  has a similar structure to extraction part  20 . The parts corresponding to one another are therefore provided with the same reference numbers. Injection part  40  has a tubular connection part  1 ′, which consists of a lower and an upper section  2 ′,  3 ′. The two sections  2 ′,  3 ′ are fixed in a snap-in manner with the interposition of a self-sealing membrane  10 ′, whereby a projecting shoulder  8 ′ of lower section  2 ′ engages in a groove  9 ′ of upper section  3 ′. Flat membrane  6 ′, which however can also be curved, is injected into lower section  2 ′. 
     Upper section  3 ′ of tubular connection part  1 ′ is again followed, via a circular rupture zone  31 ′, by a cap-shaped break-off part  16 ′, which transforms into a flat grip part  17 ′. An arrow  19 ′ pointing downwards is designed as a recess in grip part  17 ′. Arrows  23 ′ pointing downwards to indicate the flow direction are located on the outer wall of upper section  3 ′ again inside recessed grips  21 ′. 
     For the extraction of infusion solution, break-off part  16  of extraction part  20  is broken off by turning or breaking the same, so that self-sealing membrane  2  is laid bare. The spike of a known transfer system is pushed into tubular connection part  1  of extraction part  20 , as a result of which pre-slit membrane  10  is pierced and membrane  6  curved downwards is penetrated. Trough-shaped recess  13  serves as a guide for the spike. The spike is sealed by circular portion  12  of membrane  10 . On account of the special formation of injected membrane  6 , the spike is held firmly in tubular connection part  1 . 
     The infusion solution can then be extracted. When the spike is again withdrawn, self-sealing membrane  10  reliably seals extraction part  20  even in the presence of a relatively high internal pressure. Moreover, the mechanical strength of extraction part  20  is increased by the special formation of injected membrane  6 . 
     Injection part  40  serves to inject an active substance into the infusion solution. For this purpose, self-sealing membrane  10 ′ and injected membrane  6 ′ are again pierced with the injection needle of a syringe after removal of break-off part  16 ′. The injection part is again sealed after withdrawal of the needle. 
     It is to be understood that the foregoing description is intended to illustrate and not to limit the scope of the invention, which is defined by the scope of the appended claims. Other embodiments are within the scope of the following claims.