Patent Publication Number: US-2021170114-A1

Title: Device for facilitating needle injection

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application No. 62/608,981, filed on Dec. 21, 2017, which is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to needle injections, especially needle injections performed with safety pen needles. 
     BACKGROUND OF THE INVENTION 
     Safety pen needles are well known in the art to be used similar to medical injectors and other injectors, particularly medication delivery pen injectors. Shielding of a used needle before and after injection is provided by such devices. However, due to the presence of the shield, it can be difficult for a health care professional to confirm needle exposure or needle injection, as well as provide safety activation. 
     As illustrated in  FIGS. 1 and 2 , it can be difficult to confirm subcutaneous needle injection when the safety pen needle is used on a patient with a high body mass index (BMI) or having soft skin. Dimpling of the skin during injection, for example, can create problems such as varying the injection force, causing bruising from excessive pressure, activating the safety mechanism prematurely, and causing angled needle insertion. 
     Conventional pen needles can also experience problems when the skin dimples during injection. These problems include varying the injection force, causing bruising from excessive pressure and causing angled needle insertion. 
     SUMMARY OF THE INVENTION 
     It is an aspect of the present invention to provide a device to aid in pen needle injection. Such a device automatically flattens the skin of a patient, especially those with high BMI or soft skin. The device substantially self-centers the pen needle, reduces excessive force, minimizes the likelihood of premature activation, and provides for a more reliable and accurate subcutaneous needle insertion process. 
     The foregoing and/or other aspects of the present invention can be achieved by providing a device configured to aid in needle insertion by an injector, the device including a housing having a mounting surface configured to contact a skin surface, a hole configured to engage the injector and a taper substantially concentric with the hole to improve engagement with the injector. 
     Additional and/or other aspects and advantages of the present invention will be set forth in the description that follows, or will be apparent from the description, or may be learned by practice of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above aspects and features of the present invention will be more apparent from the description for the exemplary embodiments of the present invention taken with reference to the accompanying drawings, in which: 
         FIG. 1  is a side perspective view of a safety pen needle of the prior art and a skin of a patient; 
         FIG. 2  is a side perspective view of a needle of a safety pen needle of the prior art being inserted in the skin of the patient; 
         FIG. 3  is a front perspective view of a first exemplary embodiment of a device to aid in pen needle injection; 
         FIG. 4  is a cross-sectional view of the device of  FIG. 3  configured to engage a safety pen needle and mounted on the skin surface; 
         FIG. 5  is a cross-sectional view of the device of  FIG. 3  engaging the safety pen needle and the pen needle piercing the skin of the patient; 
         FIG. 6  is a front perspective view of a second exemplary embodiment of the device of  FIG. 2  with an LED; 
         FIG. 7  is a cross-sectional view of the device of  FIG. 6 ; 
         FIG. 8  is a schematic diagram of an electrical circuit of the device of  FIG. 6 ; and 
         FIG. 9  is a cross-sectional view of a third exemplary embodiment of a medication delivery pen having a pen needle configured to engage a device; and 
         FIG. 10  is a cross-sectional view of the device of  FIG. 9  engaging the pen needle and piercing the skin of the patient. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     As described above,  FIG. 1  illustrates a medication delivery pen  8  attached to a single-use safety pen needle  10  of the prior art including a housing  12 , a movable needle shield  14  forming part of a safety mechanism, and a needle cannula  16 . The safety pen needle  10  is being injected into the skin surface  78  of a patient. Problems can sometimes arise with the use of safety pen needles  10 . As illustrated in  FIG. 2 , for patients with soft skin or a high body mass index (BMI), the pressure applied to the safety pen needle  10  can cause dimpling  77  of the skin surface  78 . This dimpling  77  can create an uncontrolled and variable injection force. 
     Specifically, it sometimes cannot be accurately and consistently determined with how much force or how hard a healthcare practitioner should press the safety pen needle  10  against the skin surface  78 . As a result, the safety mechanism of the safety pen needle  10  can be prematurely activated by excessive injection force. As further described below, once the safety mechanism is activated and subsequently locked, the safety pen needle  10  is no longer operable. Alternatively, the dimpling  77  can make it difficult for the safety shield  14  to fully retract and activate the safety mechanism. In this case, if the safety mechanism does not activate, the safely pen needle  10  can potentially be reused, which is not desired. Finally, excessive injection force and applied pressure from the healthcare practitioner may also create bruising on the skin surface  78  of the patient. 
     Dimpling  77  of the skin surface  78  can also create angled insertion of the needle  16  of the safety pen needle  10 . Since a flat positioning on the skin surface  78  is difficult to achieve, many times the needle  16  of the safety pen needle  10  is not inserted in a substantially perpendicular direction to the skin surface  78 . Accordingly, the healthcare practitioner is unsure if the safety pen needle  10  is inserted into the desired subcutaneous region of the skin. If the safety pen needle  10  is inserted beyond the subcutaneous region of the skin, the muscle of the patient may be undesirably accessed. If the safely pen needle  10  is inserted and placed in the dermis or epidermis region of the skin instead of the subcutaneous region, the patient may not experience proper medication effectiveness. 
     Dimpling  77  of the skin surface  78  can make it difficult to achieve consistent depth of deposition of medicament into the subcutaneous region of the skin. In other words, injection repeatability and reducing injection variability are difficult to achieve when dimpling  77  of the skin surface  78  occurs during needle injection. 
     Angled insertion of the needle  16  in the safety pen needle  10  can cause premature activation of the safety mechanism. Further, if the safety pen needle  10  does not engage the skin surface  78  in a substantially perpendicular direction, an accidental needle stick injury to the healthcare practitioner is possible. 
     Conventional pen needles can also experience similar problems when the skin dimples during injection. These problems can include varying the injection force, causing variable depth of deposition of the medication, bruising from excessive pressure, and causing angled needle insertion. 
     To avoid the problems associated with dimpling  77  of the skin surface  78 , healthcare practitioners typically stretch the skin surface  78  to create a flat surface. Alternately, healthcare practitioners pinch the skin surface  78  of the patient to access the subcutaneous layer of the skin. However, these methods are unreliable and inconsistent ways to achieve proper needle depth and isolate the subcutaneous layer. Also, bruises may form due to the manipulation of the skin surface  78 . 
     In view of the challenges in the prior art as described above, a device  25 , as illustrated in  FIG. 3 , is provided to aid in needle insertion by an injector, such as a safety pen needle  10 . The specific device  25  shown is intended for use with a safety pen needle  10  having a retractable shield  14 , but embodiments of the device  25  can be used with any generally available safety pen needles ( FIGS. 3-8 ) and with conventional pen needles ( FIGS. 9 and 10 ), as well as with injectors other than pen needles, such as syringes. 
     As illustrated in  FIGS. 3-5 , the device  25  includes a housing  30 . Preferably, the housing  30  is made of a polymer that is transparent, or translucent and white or light in color, to allow for illumination as further described below. The housing  30  is preferably rectangular in shape, and is similar in size to a credit card. Preferably, the housing  30  is substantially shaped as a flat credit card. However, other shapes and sizes are contemplated to improve ergonomics. For example, the housing  30  can include finger grips, provide easier handling and be contoured in shape. The shape and size of the housing  30  can vary so long as an appropriate surface area is provided to engage the skin surface  78  to achieve the benefits described herein. 
     The housing  30  includes a top surface  34  and a bottom surface  38 . Preferably, both the top and bottom surfaces  34 ,  38  are substantially flat and smooth. Alternately, the top and/or bottom surfaces  34 ,  38  can be designed to include different contours such as a smooth convex or smooth concave surface. Such contours can provide a better user experience, for example, a tactile feedback identifying adequate or improved skin contact. 
     The top surface  34  has an information marking  42  including at least one of a brand or trademark, a company name and logo, patient information, teaching instructions, awareness information, an image, a barcode, and a scannable QR code (shown). In one embodiment, the patient or healthcare practitioner can use a smartphone or mobile device camera to scan the QR code which is linked to a website that provides information for proper operation of the safety pen needle  10  and the device  25 . 
     The bottom surface  38  provides a mounting surface and is configured to contact the skin surface  78  of the patient.  FIG. 4  illustrates the device  25  mounted on the skin surface  78  of the patient prior to needle insertion.  FIG. 5  illustrates the device  25  mounted on the skin surface  78  of the patient when the needle  16  of the safety pen needle  10  is inserted. As noted, the bottom surface  38  is substantially flat and smooth to advantageously create a flat skin surface  78  for needle insertion of the safety pen needle  10 . 
       FIGS. 3-5  also illustrate the housing  30  having a hole  46  that is tapered  50  and configured to engage the safety pen needle  10 . The taper  50  is substantially concentric with the hole  46 . The taper  50  and the hole  46  have a different color than the rest of the housing  30 . Preferably, the housing  30  is not tinted or is of a lighter color and can be transparent, translucent or opaque, while the taper  50  and the hole  46  is a darker color. The selected colors advantageously allow the taper  50  and the hole  46  to be more conspicuous on the housing  30 . 
     The taper  50  includes a first diameter  54  and a second diameter  58 . The first diameter  54  of the taper  50  is disposed on the bottom surface  38  of the housing  30 . The second diameter  58  of the taper  50  is disposed on the top surface  34  of the housing  30 . The second diameter is larger than the first diameter. 
     The second diameter  58  of the taper  50  is preferably sized to be slightly larger than an outer diameter of the housing  12  of the safety pen needle  10 . The first diameter  54  of the taper  50  is preferably sized to be slightly smaller than an outer diameter of the housing  12  of the safety pen needle  10 . In other words, the taper  50  is configured to substantially correspond to a tapered outer surface of the safety pen needle  10 , but allows for ease of insertion. In this manner, the depth of insertion of the safety pen needle  10  is advantageously controlled. 
     Specifically, when the safety pen needle  10  is inserted into the taper  50 , a distal end of the housing  12  of the safety pen needle  10  initially enters via a loose fit. Subsequently, the distal end of the housing  12  of the safety pen needle  10  bottoms out either loosely, with a tight fit or a snug fit, for example, and in the latter case is secured to the first diameter  54  of the device  25 . As a result, the distal end of the housing  12  of the safety pen needle  10  is flush with the mounting surface  38  of the device  25 . Accordingly, during use, the bottom surface  38  of the device  25  provide a larger and more equally distributed surface pressure on the skin surface  78  for improved needle insertion. 
     In another embodiment, the taper  50  includes a first diameter  54 , a second diameter  58  and a third diameter (not shown). The second diameter  58  is the same as in the above embodiment. The first diameter  54  is smaller than the outer diameter of the housing  12  of the safety pen needle  10  but large enough for the safety shield  14  to enter. The third diameter creates a stepped surface below the taper  50  and between the first and second diameters  54 ,  58 . The third diameter is sized slightly larger than the outer diameter of the housing  12  of the safety pen needle  10 . In operation, the safety pen needle  10  is inserted into the second diameter  58  of the taper  50  and bottoms on the stepped surface at the third diameter. Although the housing  12  of the safety pen needle  10  is not flush with the mounting surface  38 , the thickness of the stepped surface is known and so the depth of insertion can be controlled in this manner as well. 
     Additionally, as illustrated in  FIGS. 3-5 , the hole  46  and taper  50  substantially self-centers the safety pen needle  10  in the device  25  upon engagement. The hole  46  also advantageously provides for substantially perpendicular needle entry of the safety pen needle  10  upon engagement to the skin surface  78  of the patient. 
     The device  25  is intended to be easy to clean by using common cleaning methods and materials such as isopropyl alcohol, bleach, and other cleaning agents. To provide this advantage, the device  25  is designed to include, for example, no shallow crevices and no areas conducive for dirt to collect. 
       FIGS. 4 and 5  illustrate the operation of the safety pen needle  10  and the device  25 . In  FIG. 4 , the safety pen needle  10  has not yet been used. Thus, the safety mechanism is not locked. The device  25  is placed on the skin surface  78  of the patient. Specifically, the mounting surface  38  contacts the skin surface  78  via a pressing force applied by the patient or healthcare practitioner. 
     Subsequently, as illustrated in  FIG. 5 , the safety pen needle  10  is inserted into the hole  46  of the device  25 . The safety shield  14  is retracted inside the housing  12  of the safety pen needle  10  to activate the safety mechanism. At the same time, the needle  16  of the safety pen needle  10  is inserted into the skin surface  78  of the patient and medicament is delivered. 
     After medication delivery is complete, the safety pen needle  10  is removed from the device  25 . As the safety pen needle  10  is removed, the safety mechanism extends from the housing  12  to cover the needle  16 . The safety mechanism locks to permanently shield the needle  16  and prevent the safety pen needle  10  from being used again. 
     In addition to substantially self-centering the safety pen needle  10  and substantially perpendicularly entering the skin as described above, the device  25  provides additional benefits not realized by the prior art. The flat mounting surface  38  of the device  25  provides automatic flattening of the skin surface  78  at the target site. This is especially helpful for high BMI patients or patients with soft skin. The healthcare practitioner can apply a pressing force to the device  25  directly and/or through the safety pen needle  10  to cause the device  25  to contact and flatten the skin surface  78 . 
     Flattening the skin surface  78  advantageously allows for a consistent depth of deposition of medicament into the subcutaneous region of the skin. Accordingly, injections are repeatable and there is less injection variability. 
     Because of the relatively large surface area of the device  25 , a range of forces can be advantageously applied by the healthcare practitioner and still ensure that the needle  16  of the safety pen needle  10  enters into the subcutaneous layer of the skin of the patient. As a result, the use of the device  25  to assist needle insertion of the safety pen needle  10  provides better performance than manually stretching and flattening the skin or pinching the skin. 
     When the needle  16  of the safety pen needle  10  is substantially perpendicularly inserted into the skin of the patient, it is much less likely that the safety mechanism will be inadvertently or prematurely activated. Thus, it will be less likely that the safety mechanism will undesirably lock the safety pen needle  10  before use. In view of the above, when the device  25  is used for assistance, the patient and the healthcare practitioner gain more confidence in using the safety pen needle  10  and the results are more reliable. 
       FIGS. 6-8  illustrate a second exemplary embodiment of the device  25 . This embodiment is similar to the embodiment described above, but further includes a light emitting diode (LED)  70  that illuminates the transparent or translucent housing  30 . The LED  70  is disposed in the housing  30  and adjacent to the hole  46 . As illustrated in the electrical diagram of  FIG. 8 , the LED  70  is connected to a battery  72  through a switch  74  and resistor  76  for selective activation and deactivation, The switch  74  can be provided as a button or membrane switch on the top surface  34  of the housing  30 , or on a side of the housing  30  adjacent to a location where the device  25  is gripped while in use, so that the switch can be easily operated by the user. 
     The LED  70  advantageously illuminates the housing  30  to better visualize the taper  50  and the hole  46  of the device  25 . As described above, the different colors of the housing  30  with respect to the taper  50  and the hole  46  in combination with the LED  70  advantageously allow the taper  50  and the hole  46  to be even more conspicuous on the housing  30 . Thus, the healthcare practitioner and the patient can better see the self-centering mechanism of the device  25  to use the safety pen needle  10  most effectively. 
     Also, the LED  70  advantageously aids the healthcare practitioner and the patient for using the device  25  and the safety pen needle  10  in low light conditions. These low light conditions are typical in hospital and outpatient care facilities. 
       FIGS. 9 and 10  illustrate a third embodiment of a device  125  for use with a conventional pen needle  110  attached to a medication delivery pen  8 . The pen needle  110  includes a hub  112  having a main body on a proximal end of the hub  112  and a boss disposed at a distal end of the hub  112 , and a needle cannula  116 . The needle cannula  116  is fixed to the boss at the distal end of the hub  112 . 
     The device  125  is similar to the embodiment described above but is configured to be used with a conventional pen needle  110 . The device  125  includes a housing  130  having a top surface  134  and a bottom surface  138  as similarly described above. The device  125  includes a hole  146  having a first diameter  154  and a second diameter  158 . The first and second diameters  154 ,  158  are substantially concentric. The first diameter  154  is sized to be greater than the outer diameter of the needle  116  and greater than the outer diameter of the boss of the hub  112  but smaller than the outer diameter of the main body of the hub  112 . The first diameter  154  opens into a stepped surface  150 . The stepped surface  150  is a recessed surface from the top surface  134  at the second diameter  158 . The second diameter  158  is sized to be slightly larger than the outer diameter of the main body of the hub  112  to guide the pen needle  110  into the hole  146 . In another embodiment (not shown), the second diameter  158  is tapered as in the first embodiment to facilitate insertion of the pen needle  110  into the device  125 . 
     During operation, the medication delivery pen  8  is held so that the pen needle  110  is inserted into the hole  146  of the device  125 . A distal end of the main body of the hub  112  contacts and bottoms onto the stepped surface  150  of the device  125 . At the same time, the needle cannula  116  is inserted into the skin of the patient. The applied force from the user travels through the medication delivery pen  8  and to the distal end of the main body of the hub  112 . The stepped surface  150  receives the applied force and distributes the force across the bottom surface  138  of the device  125 . Accordingly, the device  125  provides many of the advantages described above, mainly to prevent dimpling of the skin surface, provide a substantially smooth surface for the needle cannula  116  to be inserted in a substantially perpendicular direction, reduce injection force variability, and reduce injection deposition depth variability. 
     The foregoing detailed description of the certain exemplary embodiments has been provided for the purpose of explaining the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use contemplated, This description is not necessarily intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Any of the embodiments and/or elements disclosed herein may be combined with one another to form various additional embodiments not specifically disclosed, as long as they do not contradict each other. Accordingly, additional embodiments are possible and are intended to be encompassed within this specification and the scope of the invention. The specification describes specific examples to accomplish a more general goal that may be accomplished in another way. 
     As used in this application, the terms “front,” “rear,” “upper,” “lower,” “upwardly,” “downwardly,” and other orientational descriptors are intended to facilitate the description of the exemplary embodiments of the present invention, and are not intended to limit the structure of the exemplary embodiments of the present invention to any particular position or orientation. Terms of degree, such as “substantially” or “approximately” are understood by those of ordinary skill to refer to reasonable ranges outside of the given value, for example, general tolerances associated with manufacturing, assembly, and use of the described embodiments.