Improved infusion system

Abstract

To construct advanced and improved components and elements of an infusion system that provides simplified manufacturing and improved use for both insulin and non-insulin applications. The present invention provides an apparatus for an infusion set including a reservoir, an introducer needle, and a catheter, the apparatus including a pump integrated with the infusion set, the reservoir including a plunger (302) with a lubricating film (304) disposed between a first elastomeric wall (306) and a second elastomeric wall (308), the elastomeric film configured to compress the lubricating film (304) when delivering a drug from the reservoir.

Description

[Technical field]

[0001] The present invention relates generally to components and elements of infusion systems, and more particularly to an infusion set having one or more features including a tube set strain relief, an infusion pump with heat exchange function, an oil immersed plunger, a two-way pump function, a piezoelectric pump device, and a reservoir made from expanded tubing. [Background technology]

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 61 / 441,278, filed February 9, 2011, to Gary M. Searle et al., entitled "Concepts for Infusion Set Strain Relief, an Oil Impregnated Plunger, a Reservoir Made from Expanded Tubing, and Piezo Pump Devices," which is incorporated herein by reference in its entirety.

[0003] Many people with diabetes use some form of daily insulin therapy to maintain precise control of their blood glucose levels. Currently, there are two main methods of daily insulin therapy. The first method includes syringes and insulin pens. These devices are easy to use and relatively inexpensive, but each injection typically requires three to four needle pricks per day. The second method involves infusion pump therapy, which requires the purchase of an insulin pump for approximately three years. Although the initial cost of the pump can be significant, from a user's perspective, the overwhelming majority of patients who have used a pump choose to stay with it for the rest of their lives. Because infusion pumps, although more complex than syringes and pens, offer the advantages of continuous insulin infusion, precise dosing, and programmable delivery schedules, the result is tighter blood glucose control and an improved sense of health.

[0004] An infusion pump is just one part of an assembly of infusion elements that work together to deliver insulin or other medications to an infusion site. Some elements are disposable, such as the infusion or pump set that transports insulin from a reservoir in the pump into the user's skin. An infusion set typically consists of a pump connector, a length of tubing, and a hub or base from which an infusion needle, flexible cannula, or catheter is delivered. The hub or base has an adhesive that holds the base of the set on the skin surface during use, which can be applied to the skin by hand or with the aid of a manual or automated insertion device.

[0005] As noted above, infusion sets allow diabetic patients to infuse insulin through an infusion pump. To do so, infusion sets use one or more of an infusion needle, a flexible cannula, or a catheter. For example, a steel infusion needle can be used to inject beneath the skin surface, into the subcutaneous or intradermal skin layer, but movement can irritate the insertion site. Alternatively, a soft Teflon-based catheter can be fitted with the infusion set to inject insulin beneath the skin surface, usually into the subcutaneous skin layer, which is associated with less irritation compared to steel cannulas. However, soft cannulas or catheters can be prone to kinking, which can slow or interrupt insulin delivery, reducing the effectiveness of the therapy.

[0006] Most soft cannula or catheter infusion sets are inserted using another commonly associated element of the infusion set, whereupon a steel introducer is positioned within the catheter lumen and extends beyond the catheter to initiate penetration. During insertion and placement, the introducer needle and catheter are both inserted into the infusion site simultaneously with or after adhesive placement of the infusion set on the skin surface. The introducer needle is then removed from the catheter after penetration, leaving the catheter in place.

[0007] Some infusion sets also include and use a separate spring-loaded inserter that drives the infusion set and / or introducer needle and catheter into tissue at a desired rate and to a desired depth. Many such spring-loaded inserters further include features that automatically retract or shield the introducer needle. Once in place, the infusion set is typically attached to the drug supply using yet another element, such as a length of tubing, that can be subject to interference and adversely affect the infusion set.

[0008] Therefore, each element of the infusion set, both separately and in combination, must operate in an optimal manner, otherwise the performance of the infusion set may be adversely affected by poor performance of the individual elements of the infusion set. Summary of the Invention [Means for solving the problem]

[0009] It is an object of the present invention to provide advanced, improved and novel components and elements of an infusion system which substantially overcomes the above-referenced and other problems, provides simplification of manufacture and further provides improved use for both insulin and non-insulin applications.

[0010] Another object of the present invention is to provide an infusion system for housing and positioning an introducer needle, infusion needle, flexible cannula or catheter, infusion set, or other skin contacting element, including a strain relief feature for a tubing set connection, which avoids the transfer of motion to the introducer needle, infusion needle, flexible cannula or catheter.

[0011] Another object of the present invention is to provide an infusion system for receiving and positioning an introducer needle, infusion needle, flexible cannula or catheter, infusion set, or other skin-contacting element, including a tubing recoiler feature for managing the tubing of a tubing set connection.

[0012] Another object of the present invention is to provide an infusion system for housing and positioning an introducer needle, infusion needle, flexible cannula or catheter, infusion set, or other skin-contacting element, including an expandable and collapsible reservoir, and incorporating such expansion and collapsing into the operation of the infusion set.

[0013] Another object of the present invention is to provide an infusion pump for use with an infusion system that is configured to operate in both forward and reverse directions and that incorporates such forward and reverse directions into the operation of an infusion set.

[0014] Another object of the present invention is to provide an infusion pump for use with an infusion system, the infusion pump being configured to incorporate a piezoelectric device and to incorporate such piezoelectric operation into the operation of an infusion set.

[0015] Another object of the present invention is to provide an infusion pump for use with an infusion system, the infusion pump being configured to incorporate a heat exchanger to maintain, cool or heat the contents or components of the pump.

[0016] Another object of the present invention is to provide an infusion pump for use with an infusion system, the infusion pump being configured to incorporate an oil immersion plunger, and to incorporate such an oil immersion plunger into the operation of an infusion set.

[0017] These and other objects are substantially achieved by providing components and elements of an infusion system that includes an infusion set having one or more features including a tubing set strain relief, an infusion pump with heat exchange capability, an oil immersed plunger, a two-way pump capability, and a piezoelectric device, as well as a reservoir made from expansion tubing, and incorporating such features into the operation of the infusion set. [Brief description of the drawings]

[0018] Various objects, advantages and novel features of the illustrative embodiments of the present invention are set forth in the accompanying drawings. The following detailed description will be better understood when read in conjunction with the drawings.

[0019] [Figure 1A]1 is a perspective view of an exemplary universal strain relief in accordance with one embodiment of the present invention; FIG. [Figure 1B] 1 is a perspective view of an exemplary universal strain relief in accordance with one embodiment of the present invention; FIG. [Figure 1C] 1 is a perspective view of an exemplary universal strain relief in accordance with one embodiment of the present invention; FIG. [Figure 2A] FIG. 13 is a perspective view of an exemplary one-piece spoke design strain relief in accordance with one embodiment of the present invention. [Figure 2B] FIG. 13 is a perspective view of an exemplary one-piece spoke design strain relief in accordance with one embodiment of the present invention. [Figure 3A] FIG. 1 is a perspective view of an exemplary universal inserter deployed strain relief in accordance with one embodiment of the present invention. [Figure 3B] FIG. 1 is a perspective view of an exemplary universal inserter deployed strain relief in accordance with one embodiment of the present invention. [Figure 3C] FIG. 1 is a perspective view of an exemplary universal inserter deployed strain relief in accordance with one embodiment of the present invention. [Figure 4A] FIG. 2 is a perspective view of an exemplary integrated strain relief in accordance with one embodiment of the present invention; [Figure 4B] FIG. 2 is a perspective view of an exemplary integrated strain relief in accordance with one embodiment of the present invention; [Diagram 5] FIG. 2 is a perspective view of an exemplary foldable strain relief in accordance with one embodiment of the present invention. [Figure 6] FIG. 2 is a perspective view of an exemplary two-piece strain relief in accordance with one embodiment of the present invention. [Figure 7A] FIG. 1 is a block diagram of an infusion system incorporating a linear peristaltic pump that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 7B] FIG. 1 is a block diagram of an infusion system incorporating a linear peristaltic pump that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 7C]FIG. 1 is a block diagram of an infusion system incorporating a linear peristaltic pump that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 7D] FIG. 1 is a block diagram of an infusion system incorporating a linear peristaltic pump that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 7E] FIG. 1 is a block diagram of an infusion system incorporating a linear peristaltic pump that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 8A] FIG. 7A is a perspective view of the infusion system of FIGS. 7A to 7E that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 8B] FIG. 7A is a perspective view of the infusion system of FIGS. 7A to 7E that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 8C] FIG. 7A is a perspective view of the infusion system of FIGS. 7A to 7E that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 8D] FIG. 7A is a perspective view of the infusion system of FIGS. 7A to 7E that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 9A] FIG. 1 is a diagram of an infusion system incorporating a piezoelectric device that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 9B] FIG. 1 is a diagram of an infusion system incorporating a piezoelectric device that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 9C] FIG. 1 is a diagram of an infusion system incorporating a piezoelectric device that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 10A] FIG. 2 is a diagram of a tubing element that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 10B] FIG. 2 is a diagram of a tubing element that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 11A] FIG. 13 is a diagram of another tubing element that can be used to deliver insulin or other medication to an infusion site according to an embodiment of the present invention. [Figure 11B] FIG. 13 is a diagram of another tubing element that can be used to deliver insulin or other medication to an infusion site according to an embodiment of the present invention. [Figure 12A] FIG. 2 is a diagram of another element that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 12B] FIG. 2 is a diagram of another element that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 12C] FIG. 2 is a diagram of another element that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 12D] FIG. 2 is a diagram of another element that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention. [Figure 13] FIG. 1 is a diagram of a tubing recoiler utilized as part of an infusion pump and infusion set connection in accordance with one embodiment of the present invention.

[0020] Throughout the drawings, like reference numbers will be understood to indicate like parts, components and structures. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Exemplary embodiments of the invention described below provide a novel means of delivering insulin via an infusion set with one or more advanced features including a tubing set strain relief, an infusion pump with heat exchange capability, an oil immersed plunger, a two-way pump function, a piezoelectric pump device, and a reservoir made from expansion tubing.

[0022] In these and other infusion systems, the use of strain reliefs may benefit the user in a variety of ways, including extending the useful life of the infusion set by reducing or eliminating micro-motions of the catheter caused by moving or tugging on the line set. Furthermore, by eliminating the effects of tugging on the line set, such strain reliefs may ultimately eliminate pull-through or leakage at the infusion site. Thus, in an exemplary embodiment of the invention, a strain relief device is incorporated into the infusion set, the inserter device, or both. Figures 1A-1C are perspective views of an exemplary generic strain relief according to one embodiment of the present invention.

[0023] In FIG. 1A, a generic strain relief 10 is illustrated, including a close-up of the assembly with tubes 20 of set 30. In the exemplary embodiment shown in FIG. 1A, the strain relief 10 comprises an adhesive layer 12, such as a pressure sensitive adhesive (PSA), secured to a base 14. The base 14 rotatably receives a pin 18 of a tube holder 16. As shown in the close-up of FIG. 1A, the pin 18 is captured within an opening 22 in the base 14, which allows 360 degree rotation of the tube holder 16. The tube holder 16 may comprise a circular segment of flexible material having an open portion to allow insertion of the tube. The circular segment may be configured to curl into an open position upon receiving a tube and to retract into a position to secure the tube once the tube is in place. An adhesive liner may also be provided to cover the adhesive layer 12.

[0024] In an exemplary use, the user first removes the adhesive liner from the lower surface to expose the bottom adhesive layer of device 10. The exposed adhesive layer is then used to secure device 10 near an infusion site, an infusion pump, or somewhere in between, such that device 10 is in full contact with the skin surface and adhesively secured thereto. The user then compresses tube 20 of the tubing set into tube holder 16 as shown in FIG. 1A.

[0025] The tube holder may further include adhesive tabs 24 as shown in FIG. 1B that may be used to hold the tubes to the tube holder. In an exemplary use, a user first removes the adhesive liner from the lower surface to expose the adhesive layer at the bottom of the device 10. The exposed adhesive layer is then used to secure the device 10 near an infusion site, infusion pump, or therebetween, as described above. The user then compresses the tubing 20 of a tube set into the tube holder, and then removes the adhesive liner from the tubes and adhesive tabs 24 that are placed over the openings of the tube holder.

[0026] The strain relief 10 of Figures 1A-1C is generic in that it can be used with any set or infusion pump, any tubing configuration, and provides 360 degree rotation of the tubing. The strain relief 10 can also be used to hold a strain relief loop in place of any set. In yet another embodiment of the invention, the strain relief device 10 can be integrated into an infusion set. Figures 2A and 2B are perspective views of another strain relief incorporated with an infusion set according to one embodiment of the invention.

[0027] 2A and 2B, an exemplary integrated spoke design strain relief 40 is illustrated, including a close-up view of the assembly with tubing 46 of an infusion set 50. In the exemplary embodiment shown, the strain relief 40 comprises one or more flexible arms 42 secured to the set 50 in a spoke design pattern. Each arm 42 comprises a slot 44 for securing the tubing 46. In particular, the slot 44 may comprise a circular segment of flexible material having an open portion to allow for insertion of the tube. The circular segment may be configured to deflect into an open position upon receiving the tube and retract into a position to secure the tube once the tube is in place. The slot may further comprise an adhesive tab (not shown) that may be used to substantially retain the tube in the slot as described in the embodiment above.

[0028] In an exemplary use, a user first places the infusion set 50 at the infusion site. The user then forms a loop of tubing and presses a portion of the tubing loop into each slot 44 of each arm 42. As shown in the close-up view of FIG. 2B, the tubing 46 snaps into the slot 44 of the arm 42, which then holds the tube 46 while providing strain relief. In this embodiment, no additional elements are required since the strain relief element is incorporated with the infusion set. Such elements that are integrated with each other or stored or placed with each other can be combined for ease of use. For example, the inserter can be configured to deploy both the infusion set and the strain relief in one motion. FIGS. 3A-3C are perspective views of an exemplary generic inserter deployed strain relief according to one embodiment of the present invention.

[0029] 3A-3C illustrate an exemplary inserter 60 having an infusion set placement opening 62 and a strain relief placement opening 64 in a single housing. The housing of the inserter 60 houses therein an infusion set and strain relief element at the distal end and a single user push button 66 at the proximal end. Both elements may be housed within and covered with an adhesive layer and layer cover (not shown). One or more push buttons 66 may be provided to actuate the inserter and simultaneously place the set 68 and strain relief 70, which may be separate elements as shown in FIG. 3A or may be integrally formed in yet another embodiment of the invention as shown in FIG. 4B described below. In doing so, a single user action may be used to place the set 68 and strain relief 70 at the insertion site without requiring a separate user action. The infusion set and strain relief may share a common adhesive base (not shown) for placement or may be provided with separate adhesive bases.

[0030] An exemplary strain relief 70 is shown in FIG. 3C, which includes a view of the assembly with tube 74 of set 68 in FIG. 3B. In the exemplary embodiment shown in FIG. 3C, the strain relief 70 comprises a patch having a raised feature and one or more flexible openings or detents 72 for snap-fitting the tubing 74. In particular, the flexible openings or detents 72 can comprise a circular opening in a flexible material having an open portion to allow insertion of the tube. The circular opening can be configured to deflect into an open position upon receiving the tube and retract to a position that secures the tube once the tube is in place. The opening can further comprise an adhesive tab (not shown) that can be used to substantially hold the tube in the opening as described in the above embodiment. As shown in FIG. 3B, the tubing 74 snaps into the opening 72 to hold the tube while providing the strain relief.

[0031] In an exemplary use, a user first grasps the inserter 60 and places the distal end of the inserter against the skin surface. The user can then press the single button 66 to automatically place the infusion set 68 at the infusion site and position the strain relief 70 near the infusion set 68. The user then forms a loop of tubing and presses a portion of the tubing loop into the flexible opening or detent 72 of the strain relief 70. In this embodiment, no additional elements are required as the strain relief element is packaged with the infusion set in the inserter 60. In other exemplary embodiments, a strain relief element can be incorporated with the infusion set. Such an exemplary strain relief element incorporated with the infusion set is shown in Figures 4A and 4B, which are perspective views of another integrated strain relief according to one embodiment of the present invention.

[0032] In FIG. 4A, a low-profile infusion set 80 is shown disposed with a tubing set connection element 82 that is integral with, but separate from, the infusion set 80. In particular, as shown in FIG. 4B, the infusion set 80 and the tubing set connection element 82 are coupled via a serpentine or zigzag patterned portion of a base 88 and a similarly patterned portion of tubing 86 between the low-profile infusion set 80 and the tubing set connection element 82. In doing so, a tubing set 84 may be attached to the tubing set connection element 82 and in fluid communication with the infusion set 80, but the infusion set 80 is isolated from movement of the tubing set 84 by the adhesive base 88 and the serpentine or zigzag patterned portion of the tubing 86.

[0033] As noted above, such elements that are integrated with each other or stored with each other or installed with each other can be combined, allowing for ease of use. In these and other exemplary embodiments of the present invention, such devices have the additional advantage that other exemplary strain relief elements are provided. For example, flexible joints or flexible materials in the tube set connections can be used in place of elements that secure the tubes at a position away from the set or secure excess portions of tubing to absorb movement. For example, FIG. 5 is a perspective view of an exemplary collapsible strain relief according to one embodiment of the present invention.

[0034] 5, flexible joint 90 is provided somewhere on the tubing set connection, on the infusion set, on the infusion pump, or anywhere in between. Flexible joint 90 may be configured as a collapsible (i.e., bellows-like) piece made from silicone or a similar material so that it can move between one end and the other. In one exemplary embodiment, flexible joint 90 may be incorporated into the infusion set itself and may include an adhesive patch 92 that is secured to the infusion site.

[0035] FIG. 6 is a cross-sectional view of another exemplary flexible joint located anywhere on a tubing set connection, an infusion set, an infusion pump, or anywhere in between. The flexible joint of FIG. 6 may be configured as a male end configured to be slidably captured within a female end to allow movement between one end and the other while maintaining a seal therebetween. The flexible joint is configured as a two-piece connectable catheter to allow movement between a male end 94 and an opposing female end 96. The female end 96 includes an opening surrounded by a detent 98. The detent 98 may be deflected upon engagement with the male end 94. In particular, the male end 94 may include a ramp 95 and a recess 97 to slidably capture the detent 98 of the female end 96 to allow some movement while maintaining a seal therebetween. The detent 98 may be strongly biased toward the recess 97 when assembled to form a fluid-tight seal between the ends 94 and 96.

[0036] As noted above, the infusion pump is another part of an assembly of infusion set elements that work together to deliver insulin or other medication to an infusion site. In an exemplary embodiment of the invention, such a device may be advantageously equipped with a medication pump that is configured to pump in both directions, such as a peristaltic or diaphragm pump. The infusion set and pump may then be configured to use the pump to empty a reservoir, ideally a flexible reservoir, pressurize an insulin vial or other medication supply, and draw fluid from the insulin vial into the reservoir. Figures 7A-7E and 8A-8D are diagrams of an infusion system incorporating a linear peristaltic pump as another part of an assembly of infusion set elements that work together to deliver insulin or other medication to an infusion site.

[0037] 7A-7E are block diagrams of an infusion system incorporating a linear peristaltic pump that can be used in combination with an infusion set to deliver insulin or other medication to an infusion site, and FIGS. 8A-8D are perspective views of an example of the use of such an infusion system. A peristaltic pump is a positive displacement pump that pumps fluid using flexible tubing that is periodically compressed and released, thereby forcing fluid through the tubing in a pumping motion. As shown in FIG. 7A, the infusion set can include a reservoir 102, a vial 104, and an introducer needle, soft catheter, or indwelling cannula 106. The reservoir 102, the vial 104, and the introducer needle, soft catheter, or indwelling cannula 106 can be connected via a valve 108. The linear peristaltic pump 100 can be located in a convenient location, such as between the reservoir 102 and the valve 108.

[0038] In Fig. 7B, the linear peristaltic pump 100 can be operated to draw air up into the introducer needle, soft catheter, or indwelling cannula 106 and into the reservoir 102. When the vial 104 is coupled to the valve 108 in Fig. 7C, the valve 108 and linear peristaltic pump 100 can then be operated to force air from the reservoir 102 into the vial 104 to pressurize the vial 104. The valve 108 and linear peristaltic pump 100 can then be operated to pump medication from the pressurized vial 104 to fill the reservoir 102 in Fig. 7D. The valve 108 and linear peristaltic pump 100 can then be operated to pump medication from the reservoir 102 into the introducer needle, soft catheter, or indwelling cannula 106 in Fig. 7E. Figs. 8A to 8D are perspective views of an example use of such a linear peristaltic pump.

[0039] FIG. 8A illustrates an assembly 110 housing one or more of a linear peristaltic pump 100, a reservoir 102, an introducer needle, soft catheter, or indwelling cannula 106, and a valve 108. In FIG. 8A, the linear peristaltic pump 100 is used to draw air into the reservoir 102. After the vial 104 is connected as shown in FIG. 8B, the linear peristaltic pump 100 is used to pressurize the vial 104 and then fill the reservoir 102 from the now pressurized vial 104. As shown in FIG. 8C, after the vial 104 is removed, the linear peristaltic pump 100 is used to pump the contents of the reservoir 102 into the introducer needle, soft catheter, or indwelling cannula 106 as shown in FIG. 8D.

[0040] Piezoelectric devices can also be utilized as part of an infusion pump, an infusion set, or as a separate component for use with either an infusion pump or an infusion set. For example, a piezoelectric pump can be used to move medication and also to vibrate an introducer needle, catheter, or indwelling cannula immediately after insertion to prevent skin tenting. The vibrations caused by the piezoelectric device or pump can help the edges of the introducer needle, catheter, or indwelling cannula cut the tissue, allowing the introducer needle, catheter, or indwelling cannula to slide smoothly into the tissue. For example, Figures 9A to 9C are enlarged perspective views of an infusion system incorporating a piezoelectric device that can be used to deliver insulin or other medication to an infusion site according to such an embodiment of the invention.

[0041] FIG. 9A illustrates an infusion set 210 coupled to a piezoelectric device 200 that can be incorporated with an infusion pump or used as an infusion pump, or can be incorporated with an infusion set or can be used as an infusion set or as a separate component for use with an infusion pump or infusion set. A piezoelectric device is a device that incorporates a material that changes shape when a voltage is applied so that the changing shape can be utilized to perform a number of tasks. In this case, the piezoelectric device 200 can be fabricated to operate as a very small pump or to generate small vibrations when controlled to do so. In an exemplary embodiment, the piezoelectric device 200 can be fabricated to transmit communicable vibrations to the infusion set 210, and in particular to an introducer needle, catheter, or indwelling cannula 202 of the infusion set 210. When the piezoelectric device 200 is utilized as part of an infusion patch pump or other infusion set, the piezoelectric actuation can be used to enhance the puncture characteristics of the introducer needle, catheter, or indwelling cannula 202 into the surface 204 of the skin as shown in FIG. 9C, which reduces, for example, tenting of the skin surface as shown in FIG. 9B of conventional insertion without vibration, which is beneficial for shallower placement of the introducer needle, catheter, or indwelling cannula. The infusion pump can incorporate such features to aid in the insertion of the needle, catheter, or indwelling cannula or to improve pump characteristics. Still other features that can be incorporated into such an infusion system or pump include a heat exchanger (not shown) to maintain the temperature of the insulin or other contents or to cool the insulin or other components of the pump if the temperature rises above a set point.

[0042] In other exemplary embodiments, the actual pump function can be performed by modifying elements of the infusion system. For example, Figures 10A and 10B are diagrams of a collapsible cylinder or reservoir that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention.

[0043] 10A and 10B are cross-sectional views of a collapsible cylinder or reservoir 220 that can be used to deliver insulin or other medication to an infusion site. In the embodiment of FIGURES 10A and 10B, an insulin vial, cartridge, reservoir, or similar element can be fabricated from a section of tubing, such as a section of infusion set tubing or other medical grade tubing, preferably a section of tubing with high elongation properties (e.g., elongation capability of 200% to 800%).

[0044] In the example shown in Figures 10A and 10B, for dimension X, the tubing expands to a length of 6X to form a chamber of length 4X, and when released, the tubing contracts to a length of 2X, essentially collapsing the entire chamber within. To do so, the tube segment can be filled with a drug, forcing the tube segment 222 into an elongated shape as shown in Figure 10A. The tube segment can be closed at either end by contoured walls 224 and 226 to reduce dead space when contracted. This filling creates enough tension to deliver the contents when released, and the tube segment 228 contracts due to its high elongation as shown in Figure 10B. The contents can be delivered through a cannula or even the tube segment 228. In yet another exemplary embodiment, the tube segment can be disposed within a chamber of a reservoir. For example, Figure 11A is a cross-sectional view of another collapsible cylinder or reservoir disposed within a structured chamber that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention.

[0045] 11A and 11B are enlarged cross-sectional views of a collapsible cylinder or reservoir 240 disposed within a structured chamber that can be used to deliver insulin or other medication to an infusion site. In the embodiment of FIG. 11A, an insulin vial, cartridge, reservoir, or similar element is fabricated from a section of tubing 242, such as a section of tube set tubing or other medical grade tubing, preferably a section of tubing with high expansion properties. The tube segment can be disposed within a housing 250 or other tube segment. Thus, the tube segment 242 can be filled with medication, forcing the tube segment 242 into an expanded shape as shown. The tube segment 242 can be closed at either end by contoured walls 244 and 246 to reduce dead space when contracted. At least one of the contoured walls, such as the contoured wall 244 of FIG. 11A, can have a space or gap in slidable contact with the housing 250 to provide clearance for collapsing a section of the tube segment 242 when collapsed, as shown in FIG. 11B. This filling creates enough tension to deliver the contents when released, allowing the tube segment 242 to contract due to its high expansion properties and fold into the gap provided in the contoured wall 244. The contents can be delivered through the cannula or even through the tube segment 248.

[0046] The housing 250 can be sized to prevent contact with the expanding tube segment 242, or the outer diameter of the tube segment 242 can be lubricated so that the surface of the tube segment 242 slides freely across the inner surface of the housing 250. In yet another exemplary embodiment, one or more of the moving wall segments within the reservoir can be provided with a lubricating film that provides lubrication for moving elements. For example, Figures 12A through 12D are cross-sectional views of such an embodiment that can be used to deliver insulin or other medication to an infusion site according to one embodiment of the present invention.

[0047] 12A is a cross-sectional view of a reservoir housing 300 with one or more moving wall segments, such as a plunger or stopper 302 with a lubricating film 304 (i.e., oil-immersed film) between rigid elastomeric walls 306 and 308. In the exemplary embodiment shown, the moving wall segment 302 is a syringe or reservoir plunger or stopper in which lubricating features are configured such that the remainder of the syringe or reservoir does not require a separate lubricating coating on the inner walls. By impregnating an O-ring, washer, disk, or other porous membrane 304 within the plunger or stopper 302 with a lubricating oil and designing the plunger or stopper 302 to release the porous membrane 304 lubricant only when a dispensing / injection force is present, the moving walls of the syringe or reservoir are lubricated, but the insulin or other drug contents are preferably not exposed to the porous membrane 304 lubricant at all, or in other cases, until the infusion begins, at which point exposure is minimal throughout the infusion process.

[0048] To do so, the lubricating film 304 and elastomeric walls 306 and 308 are configured to be driven along the central axis by a syringe engagement portion 310 when filling from a vial 312 as shown in FIG. 12A. The syringe engagement portion 310 drives the plunger or stopper 302 without compressing the lubricating film 304, thus allowing the syringe to be utilized to fill or empty the syringe from the vial 312. The syringe engagement portion 310 can be removed as shown in FIG. 12B and replaced with a pump engagement portion 314 as shown in FIG. 12C. The pump engagement portion 314 is not configured to drive the plunger or stopper 302 along the central axis together with the syringe engagement portion 310, but rather defines a wider contact element 316 that extends beyond the central axis. In doing so, the wider contact element 316 of the pump engagement portion 314 presses against the outer diameter of the elastomeric wall 308 of the plunger or stopper 302, bending the wall 308 into the membrane 304, compressing the lubricating film 304 and releasing the lubricant between the outer diameter of the plunger and the inner diameter of the reservoir, as shown in FIG. 12D. Thus, the lubricant in the lubricating film 304 is only dispensed when a dispensing / injection force is present, and thus the insulin or other drug contents are preferably not exposed to the lubricant in the porous membrane 304 at all, or otherwise, until the infusion begins, at which point exposure is minimal throughout the infusion process. These embodiments described above incorporate pump features that are advantageous to the drug or pump operation. However, in still other exemplary embodiments, the pump can incorporate features unrelated to pump operation, but still form part of an assembly of infusion set elements that work together to deliver insulin or other drug to the infusion site. As an example, FIG. 13 shows a tubing recoiler utilized as part of an infusion pump.

[0049] FIG. 13 is a perspective view of a tubing recoiler utilized as part of an infusion pump. The infusion pump 350 is shown coupled to an infusion set 352 via a length of tubing 354. However, excess tubing between the infusion pump 350 and the infusion set 352 can be subject to interference and transfer undesired movement to the infusion set 352 through contact. Therefore, it is desirable to minimize the length of tubing 354, while providing sufficient length to allow ease of use and ease of placement of the infusion set 352. In other systems, a separate tubing recoiler 360 is provided to perform this function. However, providing such a separate element requires the user to carry, install, and manage a separate component. Therefore, in an exemplary embodiment of the present invention, a separate tubing recoiler is incorporated into the infusion pump 350.

[0050] In particular, pump 350 integrates the tubing and recoiler to automatically recoil excess tubing via a spring mechanism or other methods and dispense the tubing in reverse, thus eliminating the need for other separate devices to manage excess tubing. Tubing 354 connecting insulin supply and pump 350 to infusion set 352 can be packaged on a spring-loaded circular reel disposed within pump 350. Tubing 354 enters and exits pump 350 and winds around a spring mechanism. The construction of spring-loaded circular reels is known to those skilled in the art, and additional features of such reels have been omitted for clarity. The circular reel can further include a catch / latch mechanism as known to those skilled in the art such that a first pull on tubing 354 dispenses a length of tubing, the catch being provided to prevent reverse spring bias. After a second pull on tubing 354, the catch is released to allow reverse spring bias to bias tubing 354 into pump 350. In doing so, a reeling device allows for precise delivery of slack tubing, with spring resistance keeping excess tubing wound up and stored. A locking catch or latch can be provided to prevent the user from inadvertently retracting or extending after a sufficient length of tubing has been deployed.

[0051] In an exemplary embodiment of the invention, the housing, hub, and other elements of the infusion system may be made from molded plastic materials, thermoplastic polymers such as polycarbonate, polyethylene terephthalate (PET or PETG), or similar materials. The spring and introducer needle may be made from stainless steel or similar materials. Although the embodiments described above are sized and configured to perform subcutaneous injections, they may also be used for other types of injections, such as intradermal or intramuscular injections.

[0052] Additionally, features such as 360 degree or partial rotation, line set connections, septum placement, etc., may be located in the strain relief rather than in the base or hub of the infusion set where the Teflon cannula or catheter is secured. The strain relief may then be used to minimize the effects of movement or tugging on the line set and movement occurring on the catheter or cannula. This includes (1) tugging on the line set, such as occurs when the line set gets caught on a doorknob or other object and force is applied to pull the infusion set away from the skin, and (2) forces applied directly to the infusion hub, such as when the patient or infusion set hits an object and forces are applied to the outside of the infusion set, or when the patient turns over in their sleep.

[0053] Additionally, one or more of the exemplary embodiments of the present invention may include an adhesive layer and backing that contacts the skin. Accurate insertion is accomplished by first removing the adhesive cover of the adhesive layer, then adhesively securing the infusion set hub to the infusion site, and the user may actuate the inserter or place the catheter as described above with proper alignment. After adhesive attachment, the introducer needle, indwelling cannula and / or catheter are pushed into the skin surface at a controlled, fast rate to minimize risk of slippage during insertion. Additionally, adhesive is applied at or very close to the insertion site to secure the skin surface and minimize tenting of the skin surface during insertion.

[0054] In current infusion sets that deliver insulin or other medications to the subcutaneous layer, the catheter is typically not insulated from unwanted external forces, which can then cause pain as the catheter turns into moving into the skin. Also, other devices face the problem of premature or unintended catheter removal when the device is bumped, if the catheter is not insulated from external forces. In an exemplary embodiment of the invention, the catheter may be insulated from external forces by at least one flexible or resilient feature or strain relief.

[0055] Although only a few exemplary embodiments of the present invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without substantially departing from the novel teachings and advantages of the present invention, and all such modifications are intended to be within the scope of the appended claims and their equivalents.

Claims

[Claim 1] 1. An apparatus for an infusion set comprising a reservoir, an introducer needle and a catheter, the apparatus comprising a piezoelectric pump integrated with the infusion set, the piezoelectric pump configured to transmit vibrations to at least one of the introducer needle and the catheter, the piezoelectric pump configured to transfer a medication between the reservoir and the catheter.

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