Abstract:
A device for facilitating the use or application of skin penetrators, the device including a puncturing part for piercing the skin, an indwelling part which can be introduced into the skin through an opening generated by the puncturing part and remains there, wherein the puncturing part and indwelling part are operably associated with the device, and a guide operably associated with the device, wherein, in use, the indwelling part is moved, via the guide, into a position of use after the puncturing part has pierced the skin. In some embodiments, the puncturing and indwelling parts are separate from each other prior to use. A method of using skin penetrators is encompassed and includes sequentially introducing the puncturing part and the indwelling part into the skin.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
       [0001]    This application is a continuation of International Application No. PCT/EP2006/001715, filed on Dec. 24, 2006, which claims priority to German Application No. 05 004 760.4, filed on Mar. 4, 2005, the contents of both of which are incorporated in their entirety herein by reference. 
     
    
     BACKGROUND 
       [0002]    The present invention relates to devices for injecting, infringing, administering, delivering and dispensing substances, and to methods for making and using such devices, as well as to related peripheral, adjunct, complementary, cooperative and auxiliary devices and methods. More particularly, the present invention relates to the sequential application or use of skin penetrators. In the context of the present invention, the expression “skin penetrators” signifies devices that are introduced through the skin into the body from outside the body. For example, these can be cannulas for administering medicaments, probes that are inserted into the skin or into the underlying tissue, or sensors for measuring a physiological parameter, such as glucose sensors. 
         [0003]    Elements of such devices are a puncturing part, which pierces the skin, and an indwelling part, which is introduced into a skin opening or channel formed by the puncturing part and remains there. Known designs have a relatively soft cannula, which is made of plastic material and which forms the indwelling part, and a steel cannula, which is provided with a tip and which extends through the plastic cannula, the tip protruding from the front of the plastic cannula. Upon application or in the use of these known designs, the puncturing part and indwelling part are inserted together, after which the steel cannula is withdrawn from the plastic cannula, such that only the plastic cannula remains in the body. The plastic cannula is attached to a line system (in most cases via an adapter, which can also serve as a guide for the steel cannula) to allow liquid to flow in or out through the skin. 
         [0004]    Disadvantages of known systems of this kind include the following: the steel cannula has to be removed and disposed of in a separate operating step. If it remains in the body during the wearing period, it is found to be uncomfortable or painful. The geometry of the cutting edge for the tip of the steel cannula must protrude from the plastic cannula and thus increases the overall length by several millimetres. Introducing the steel cannula into the plastic cannula during the manufacture of the system proves difficult if the soft plastic cannula is even just slightly bent. The plastic cannula could then be damaged or destroyed by the tip of the steel cannula. 
       SUMMARY 
       [0005]    An object of the present invention is to make available a device for facilitating the use or application of skin penetrators and which addresses the abovementioned disadvantages of known designs. Another object is to make available an applicator device for skin penetrators, which applicator device is easy to handle, is well tolerated and functions well. 
         [0006]    Thus, in one embodiment, the present invention comprises a device for facilitating the use or application of skin penetrators, the device comprising a puncturing part for piercing the skin, an indwelling part which can be introduced into the skin through an opening generated by the puncturing part and remains there, wherein the puncturing part and indwelling part are operably associated with the device, and a guide operably associated with the device, wherein, in use, the indwelling part is moved in or onto the guide after the puncturing part is moved in or onto the guide. 
         [0007]    In one embodiment, the device further comprises a housing carrying the guide, and the guide comprises an abutment for contact by at least one of the puncturing part and the indwelling part, the abutment forming a hold point for at least one of the puncturing part and the indwelling part, wherein the puncturing part and the indwelling part are guided in the guide in a movement that brings the puncturing part into contact with the abutment thereby holding the puncturing part at the hold point, the movement then continuing carrying the indwelling part into a use position. In some embodiments, the puncturing part and the indwelling part may be separate from each other and the device prior to use. In some embodiments, the movement may be a movement in or during at least part of which the puncturing part and the indwelling part are operably coupled. 
         [0008]    In one embodiment, the present invention comprises a method for the use of skin penetrators, the method involving a device comprising a puncturing part, which pierces the skin, and an indwelling part, which is introduced into the skin through an opening generated by the puncturing part and remains there, and comprising the step of introducing the puncturing part and the indwelling part into the skin sequentially via a guide associated with the device. 
         [0009]    In one embodiment, the present invention comprises a device for facilitating the use or application of skin penetrators, the device including a puncturing part for piercing the skin, an indwelling part which can be introduced into the skin through an opening generated by the puncturing part and remains there, wherein the puncturing part and indwelling part are operably associated with the device, and a guide operably associated with the device, wherein, in use, the indwelling part is moved, via the guide, into a position of use after the puncturing part has pierced the skin. In some embodiments, the puncturing and indwelling parts are separate from each other prior to use. A method of using skin penetrators is encompassed and includes sequentially introducing the puncturing part and the indwelling part into the skin. 
         [0010]    In some embodiments, the device for application of skin penetrators according to the present invention is characterized in that the puncturing part and the indwelling part are provided separately on the applicator device, and by at least one guide in or on which the indwelling part is brought after the puncturing part into the puncture position thereof to be introduced into the skin. 
         [0011]    Alternatively, the puncturing part and the indwelling part can be mounted on two separate devices or can be designed as two separate devices. A one-part design of the device is one preferred embodiment, i.e. the puncturing part and the indwelling part are component parts of one device. 
         [0012]    In some embodiments, the puncturing part and indwelling part are produced and/or provided spatially separately and alongside one another and are introduced sequentially into the skin. The guide ensures that the indwelling part is exactly in a position above the pre-formed hole when it is introduced into the skin. In some embodiments, a device is preferred in which the puncturing part and the indwelling part are arranged in or on a housing. 
         [0013]    Advantageously, it is therefore no longer necessary to make the puncturing part longer than the indwelling part. Both parts can be of the same length, such that the skin is not pierced any further or more deeply than is necessary. In some embodiments, a puncturing part is preferred that is less long than the indwelling part, e.g., less than approximately half as long as the puncturing part. In some preferred embodiments, the puncturing part may have a length that is less than approximately one third of the length of the indwelling part. 
         [0014]    In some embodiments, a steel needle, which, in some embodiments may be solid, i.e., not hollow, can be used as the mechanical puncturing part. Other types of needles could be used, as well as needles made of other materials. 
         [0015]    The provision of the guide assists the user by ensuring that it is not possible to make an error when introducing the indwelling part, e.g., that the channel formed in advance by the puncturing part will be reliably targeted. The puncturing part does not remain in the channel, with the result that the user does not experience discomfort. 
         [0016]    According to one embodiment of the present invention, the guide is able to guide the puncturing part and the indwelling part, and it can have a hold point assigned to the puncture position or application (or use or indwelling) position. The puncturing part can, for example, include a puncturing part support on which a puncturing element for opening the skin is mounted. 
         [0017]    In some embodiments, the hold point may be formed by an abutment for the puncturing part and/or the indwelling part. Such an abutment has the advantage that it helps provide for positioning accuracy. If an abutment is provided, it is advantageous that the puncturing part and the indwelling part are guided in the guide with coupled movement, and the hold point is generated by an abutment onto which the puncturing part is guided after the puncturing procedure, the continued movement thereby carrying the indwelling part into its application or use position. 
         [0018]    The hold point already discussed above can, in principle, be formed by a locking engagement for the puncturing part and/or the indwelling part, the locking engagement being arranged in or on the guide. In this case, it is advantageous if a single releasable locking engagement is provided in or on the guide, into which first the puncturing part and thereafter the indwelling part can lock. 
         [0019]    According to a preferred embodiment of the present invention, a retaining member is present on or in the guide and retains the puncturing part in the retracted position (after the preliminary puncture) or holds the coupled unit of the separate puncturing part and indwelling part in the use position of the indwelling part. An advantage lies in the fact that, after the indwelling part has been brought into the application or indwelling use position, no inadvertent displacement can take place, with the result that a precise positioning of the indwelling part over the pre-formed channel is substantially guaranteed. 
         [0020]    In a further embodiment, the puncturing part and the indwelling part can be received in a housing in which the guide and the abutment is/are accommodated, the housing having a passage for the puncturing part and the indwelling part. The housing can be adapted such that it facilitates the handling of the entire device and also accommodates or secures additional elements that may be needed or useful. 
         [0021]    In a preferred variant of the device according to the present invention, a puncturing part receiver can be arranged on the guide or in the housing to receive the puncturing part, after removal from the puncture position, and to safely stow it away. In some embodiments of the device according to the present invention, the puncturing part is retracted or removed from its position above the pre-formed channel after a piercing operation. If it is guided into the puncturing part receiver described above, the advantages are, on the one hand, that it no longer has to be disposed of and, on the other hand, it no longer poses a risk of injury to the user. 
         [0022]    According to an advantageous embodiment of the present invention, an additional or integrated component part in the form of a skin tensioner can be arranged on the guide or on the housing. After the puncturing procedure, it engages on the skin around the channel and holds the channel open, such that the indwelling part can be introduced even more easily. 
         [0023]    The above-described guide for the puncturing part and indwelling part can be of any desired configuration. It can be a curved guide, a linear guide or a combination of curved and linear guide. It is advantageously configured such that the piercing movement of the puncturing part and the application movement of the indwelling part can be executed independently of one another, even if the two said parts are otherwise coupled in terms of motion. 
         [0024]    In another preferred embodiment of the device according to the present invention, the movements of the puncturing part and of the indwelling part are coupled in such a way that the return movement of the puncturing part partially overlaps the insertion movement of the indwelling part. In some preferred embodiments, this partial overlap involves the puncturing part being withdrawn almost completely from the skin, and only its distal tip still being located in the skin, and overlapping the insertion movement of the indwelling part. 
         [0025]    In another advantageous embodiment of the device according to the present invention, the indwelling part is made of a material that has a greater stiffness at ambient or room temperature than it does at body temperature. It is possible, for example, to use plastics that are relatively rigid at a time before introduction of the indwelling part to make it easier to introduce the indwelling part into the skin. This can be achieved using a temperature-sensitive material that is relatively rigid at room temperature or “normal” ambient temperature (about 18 to 24° C.) but becomes relatively soft in the skin, that is to say at body temperature/skin temperature. 
         [0026]    In some embodiments, the invention also relates to a method for application or use of skin penetrators with a puncturing part, which pierces the skin, and with an indwelling part, which is introduced into an opening or channel generated in the skin by the puncturing part and remains there. In one embodiment of the method, the puncturing part and the indwelling part, which are provided separately on an applicator device, are introduced sequentially into the skin by a guide. The indwelling part and the puncturing part are brought into the puncture position in or on the guide. 
         [0027]    The method has the advantages that have already been described above in connection with the device according to the present invention. When carrying out the method, a device of the kind that has already been described above in various embodiments can be used. 
         [0028]    As used in the context of the present application, the expression “puncturing part” includes not only mechanical structures such as needles, for example, but also jets of liquid (which can be used to open the skin), lasers and pyrotechnic devices. 
         [0029]    As used in the context of the present application, the expression “sequential introduction” includes not only a complete time separation of the two procedures (insertion of the puncturing part and application (or use, placing or insertion) of the indwelling part), but also procedures in which there is a time overlap between the puncturing procedure and the application procedure, i.e. the two procedures are dephased. A possible overlap entails, for example, that the indwelling part is already introduced into the skin while the puncturing part is being withdrawn from the skin. A further overlap entails that the puncturing part is almost completely retracted from the skin when the indwelling part is being introduced into the skin. This, in some embodiments, the movements of puncturing part and indwelling part are coupled but not identical, i.e. staggered in time. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]      FIG. 1  shows a first embodiment of a device according to the present invention for application or use of skin penetrators, with a rotary blade as a puncturing part, before use; 
           [0031]      FIG. 2  shows the device of  FIG. 1  after its use; 
           [0032]      FIG. 3  shows a second embodiment according to the present invention with a puncturing part guided in a translation movement, before use; 
           [0033]      FIG. 4  shows the embodiment of  FIG. 3  after its use; 
           [0034]      FIG. 5  shows a front view of an example of a drive device for introducing the puncturing part of a device according to the present invention, in a starting position, before introduction of the puncturing part; 
           [0035]      FIG. 6  shows a rear view of the drive device according to  FIG. 6 ; 
           [0036]      FIG. 7  shows a front view of the drive device according to  FIG. 5 , with the puncturing part introduced into the skin; 
           [0037]      FIG. 8  shows a rear view of the drive device according to  FIG. 7 ; 
           [0038]      FIG. 9  shows a front view of the drive device according to  FIG. 5 , with the drive element located in the lower end position; 
           [0039]      FIG. 10  shows a rear view of the drive device according to  FIG. 9 ; 
           [0040]      FIG. 11  shows a front view of the drive device according to  FIG. 5 , with the puncturing part located in the upper end position after retraction from the skin; 
           [0041]      FIG. 12  shows a rear view of the device according to  FIG. 11 ; 
           [0042]      FIG. 13  shows a front view of a device according to the present invention for introduction of skin penetrators, with a puncturing part guided through a curved trajectory; 
           [0043]      FIG. 14  shows a plan view of the device of  FIG. 13 ; 
           [0044]      FIG. 15  shows a two-part device for introduction of an indwelling part into tissue, and 
           [0045]      FIG. 16  is a three-dimensional depiction of an embodiment of a sequential device in accordance with the present invention, the device being for introduction of skin penetrators. 
       
    
    
     DETAILED DESCRIPTION 
       [0046]      FIGS. 1 and 2  depict one embodiment of a device according to the present invention. The device is for use in the introduction of skin penetrators into the skin, and  FIG. 1  shows the device  1  before use, i.e. before introduction of the skin penetrator into or through the skin, and  FIG. 2  shows the situation after the skin penerator has been introduced into the subcutaneous tissue. 
         [0047]    The housing upper part  2  is connected to the housing lower part  4  by an attachment ring  3 . (It should be appreciated that relative and/or positional terms, e.g., upper, lower, top, bottom, etc., are, unless otherwise stated, used for convenience not limitation.) In this example, a rotary blade  5  serves as the puncturing part. Before use, the rotary blade  5  is held in the starting position by a clip  6 . A spring  7  serves as the means of driving the rotary blade  5  and, in the starting position illustrated, is tensioned. The underside  9  of the housing  4  is positioned on a skin surface and has an opening  10  in the area of the rotary blade  5 , such that a sharp edge of the rotary blade  5  emerges from the housing underside  9  and can pass through or open the skin. The indwelling part  11  is introduced into the skin through the same opening  10 . 
         [0048]    The rotary blade  5  is arranged in the device in such a way that, upon use of the device, it makes a small incision in the upper layers of the skin, which incision is sufficient to allow the indwelling part  11  to pass through the skin and be positioned in the subcutaneous tissue of a patient. 
         [0049]    The introduction of the skin penetrator using the device from  FIGS. 1 and 2  proceeds as follows: 
         [0050]    A downwardly directed force is applied to the housing upper part  2  and pushes the latter in the direction of the skin, the housing upper part  2  being guided in a sliding movement by the attachment ring  3 . This downwardly directed movement of the housing upper part  2 , i.e. in the direction of the skin, leads to a lateral displacement of the clip  6  and to rotation of the rotary blade  5 . A sharp edge of the rotary blade  5  turns through the opening  10  out of the housing lower part  4 , makes an incision in the upper layers of the skin and then turns back to its end position in the housing as far as the abutment  8 . 
         [0051]    After the rotary blade  5  has made an incision in the skin, the indwelling part  11 , for example a sensor for measuring the glucose concentration in the interstitial tissue, is introduced through the opening  10  of the housing lower part  4  and into the subcutaneous tissue. This is achieved by further displacing the housing upper part  2  in the direction of the skin until it has reached its end position. In the end position, the housing upper part  2  and the housing lower part  4  run into one another and, in some preferred embodiments, establish a force-fit connection. The attachment ring  3  can then be removed from the device or falls off. 
         [0052]    The indwelling part  11  is arranged in the device in such a way as to pass exactly through the incision made with the rotary blade  5 . This arrangement of the indwelling part  11  in the device has the advantage that only a small incision has to be made, i.e. the device according to the invention permits gentle introduction of sensors, for example, into the skin. 
         [0053]      FIG. 3  shows a second embodiment of a device according to the present invention before its use, and  FIG. 4  shows the device after introduction of the indwelling part into the subcutaneous tissue of a human, i.e. after its use. 
         [0054]    The second embodiment differs from the first embodiment, shown in  FIGS. 1 and 2 , in terms of the design of the puncturing part  5  which, in the second embodiment, is arranged so as to be linearly displaceable in a guide  12 . 
         [0055]    The puncturing part  5  is held in the starting position in the guide  12 , for example by a pin (not shown). A spring  13  serves as the drive means for displacing the puncturing part  5  in the direction of the surface of the skin. Upon use of the device, the housing upper part  2  is displaced in the direction of the skin, i.e. downward. This downward movement releases the pin, and the puncturing part  5  is introduced into the skin by the tensioned spring  13 . The puncturing part  5  is forced forward by the spring  13 , until the spring  13  moves into the end position along with the puncturing part  5 . At this moment, the retaining spring  14  becomes active and forces the puncturing part  5  back into the starting position. After completed application of the device, the attachment ring  3  can be removed, or it falls off automatically after the application. 
         [0056]    Instead of the spring  13  as the drive mechanism or power provider for introduction of the puncturing part  5 , it is also possible, for example, to use gas pressure or an elastomer. 
         [0057]      FIGS. 5 to 11  show a drive device for introducing the puncturing part of a device according to the present invention. In these drawings, the indwelling part, which is introduced into the skin, is not shown.  FIGS. 5 ,  7 ,  9  and  11  show a front view of the device, and  FIGS. 6 ,  8 ,  10  and  12  show a rear view, with adjacent figures showing the same state of the device. 
         [0058]    The drive device comprises a slotted plate  20 , a drive element  21  and a puncturing part  5 . The drive element  21  is connected by a spring steel sheet  22  to the puncturing part  5 , which is guided in an F-shaped slot  24 . The slot  24  is characterized by a puncturing part receiver  26  into which the puncturing part  5  is guided after the puncturing procedure has been carried out. The drive element  21  can be driven by a pretensioned draw spring or compression spring or an elastomer band and is guided in the slot  25 . 
         [0059]    Referring to  FIGS. 7 to 12 , the mechanism of the drive device can be described as follows: 
         [0060]    The drive element  21  moves downward in the slot  25 , i.e. in the direction of the surface of the skin. The puncturing part  5  is carried in the direction of the skin via the spring steel sheet  22  and penetrates the surface of the skin in the lower end position ( FIGS. 7 and 8 ). 
         [0061]    The drive element  21  moves further in the direction of the surface of the skin and reaches its lower end position ( FIGS. 9 and 10 ). It will be seen from  FIG. 10  that, in the lower end position of the drive element  21  and of the puncturing part  5 , the spring steel sheet  22  has deformed, i.e. the spring steel sheet is tensioned. The tensioning of the spring steel sheet  22  means that the puncturing part  5  is pushed upward in the slot  24  from its lower end position and deviates sideways into its upper end position ( FIGS. 11 and 12 ). 
         [0062]    The lateral deviation of the puncturing part  5  frees the slot  24 , in which an indwelling part, for example a sensor, can then be introduced into the skin through the opening created in the skin by the puncturing part  5 . The movement of the puncturing part  5  can be coupled to the movement of the indwelling part in such a way that the movement of the indwelling part is triggered as soon as the puncturing part  5  has reached its upper end position. 
         [0063]    The spring steel sheet  22  shown in  FIGS. 5 to 11  can be replaced, for example, by a leg spring. 
         [0064]      FIG. 13  depicts a front view of a further embodiment of the present invention, and  FIG. 14  shows a plan view of the device. The device is positioned on a patient&#39;s skin over a plaster  30 . 
         [0065]    The device comprises a housing  31 , a puncturing part  5 , an indwelling part  11  and two interconnected mechanisms, the first mechanism being used to drive the puncturing part  5 , i.e. the first mechanism allowing the surface of the skin to be opened by the puncturing part  5 . The second mechanism controls the introduction of the indwelling part  11  into the subcutaneous tissue. 
         [0066]    The puncturing part  5  is introduced into the skin via a pretensioned leg spring  32 , which is driven by two crank arms  33  and  34 , and along a curved path  35  integrated in the housing, and it is retracted into the housing after introduction is complete. After the puncturing part  5  has been retracted into the housing  31 , a small opening  36  remains in the skin. The indwelling part  11 , which is driven by a pretensioned leg spring  37  and a toothed gear  38 , is introduced by a guide element  39 , and the curved path  40  integrated in the housing, through the skin opening  36  formed by the puncturing part  5  and into the subcutaneous tissue. 
         [0067]    The puncturing procedure can be triggered manually by a user, for example via an actuating button (not shown). The subsequent application procedure for introduction of the indwelling part  11  is triggered by the crank arms  33  and  34 , i.e. the introduction of the puncturing part and the introduction of the indwelling part are coupled to one another such that the introduction of the indwelling part  11  is triggered after retraction of the puncturing part  5 . 
         [0068]      FIG. 15  shows an embodiment of the present invention in which the puncturing part and the indwelling part are not provided as component parts of one device, but instead are designed as two separate devices. A conventional puncturing aid, such as, for example, those known as the Accu-Check Softclix or Accu-Check Multiclix, can be used as the puncturing device. The indwelling part, for example a sensor, can be integrated in a device that includes, for example, the electronics for controlling the sensor, a data memory, and a telemetry system for transferring data to a third appliance. 
         [0069]    In the embodiment of the present invention comprising two separate devices, an embodiment of the method for application of a subcutaneous sensor, for example, is as follows: 
         [0070]    A patient arranges a positioning ring  51 , for example, on the area of skin where he wishes to apply the sensor. The positioning ring  51  has, for example, a planar underside, with an opening  52  through which the puncturing part  5  of the puncturing device  50  is introduced, and a circumferential surface. To ensure that the positioning ring  51  adheres to the surface of the skin, it has a plaster or adhesive, for example, on its underside. The puncturing device  50  is then fitted into the ring and fixed releasably therein, to permit precise piercing of the skin. The puncturing device  50  can be fixed in place via the circumferential surface of the ring, for example. 
         [0071]    The patient then carries out the puncturing procedure and releases the puncturing device  50  from the positioning ring  51  after the puncturing procedure has been completed. He then introduces the sensor, for example, of the indwelling device through the opening in the skin and fixes the indwelling device on the positioning ring. After use, the indwelling device is removed with the positioning ring from the surface of the skin and is disposed of. 
         [0072]      FIG. 16  shows another example of a device for sequential introduction of an indwelling part  11  in accordance with the present invention. The device comprises a vertically guided base plate  60 , a drive device  61 ,  62 ,  63 , and a puncturing part  5 . 
         [0073]    The drive device comprises a spring steel wire, which is bent at one location into a helical spring  61  and has clips  62 ,  63  which protrude at two locations and which act sequentially on the puncturing part  5  and on the indwelling part  11 . 
         [0074]    The clips  62  and  63  are mutually offset by 90°, such that the clip  62  first presses the puncturing part  5  down via a clip  64 , after which the clip  63  presses the indwelling part  11  down via a force acting on the base plate  60 . During the insertion procedure, the clips  62  and  63  turn through almost 180°. The angle offset has the effect that the clip  62  executes a vertical downward movement followed by an upward movement, while the clip  63  moves exclusively downward in the vertical direction. 
         [0075]    The described procedure can also be realized using two offset cam discs that are coupled to a drive. 
         [0076]    In an alternative design, the clip  63  does not act as a drive, but instead as inhibitor on the base plate  60 , which in this case is driven downward by an external drive (not shown). 
         [0077]    Embodiments of the present invention, including preferred embodiments, have been presented for the purpose of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms and steps disclosed. The embodiments were chosen and described to provide the best illustration of the principles of the invention and the practical application thereof, and to enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth they are fairly, legally, and equitably entitled.