Catheter insertion device and catheter insertion method

Abstract

The catheter insertion device includes a housing, a body, and a button, the button being movable to the housing and movable between an elevated position and a lowered position, and the needle hub being coupled to the button so as to move together with the button between the elevated and lowered positions. In the elevated position, the body of the button is at a first distance from the needle hub, reducing visibility of the needle hub through the body of the button. In the lowered position, the body of the button is at a second distance from the needle hub, which is shorter than the first distance that allows visibility of the needle hub through the body of the button.

Description

Technical Field

[0001] The present invention generally relates to medical infusion systems such as insulin injection devices or insertion devices, where a simple, low-profile, low-part-count manual insertion device comprises a dual-retreat spring configuration for automatic introducer needle retraction. The dual-retreat spring configuration is implemented using a plurality of barrel-shaped guides and bosses within the insertion device housing, thereby allowing the use of a retraction spring much smaller than that of a single-barrel configuration.

Background Art

[0002] Diabetes is a group of diseases characterized by hyperglycemia resulting from the inability of a diabetic patient to maintain appropriate levels of insulin secretion when needed. Diabetic patients require some form of daily insulin therapy to maintain control of their glucose levels. Diabetes can be dangerous for affected patients if left untreated and can lead to serious health complications and premature death. However, such complications can be minimized by utilizing one or more treatment methods to control diabetes and reduce the risk of complications.

[0003] Treatment methods for diabetic patients include special dietary therapy, oral medications, insulin therapy, etc. The main objective of diabetes treatment is to control the blood glucose level or sugar level of diabetic patients. However, maintaining appropriate diabetes management can be complex because the activities of diabetic patients must be balanced.

[0004] There are two main methods of daily insulin therapy for the treatment of type 1 diabetes. In the first method, diabetic patients self-inject insulin using a syringe or insulin pen as needed. This method requires a needle prick for each injection, and diabetic patients may need 3 to 4 injections per day. The syringes and insulin pens used for insulin injection can be used relatively easily and are cost-effective.

[0005] An effective method for insulin therapy and diabetes management is infusion therapy using an insulin pump, or infusion pump therapy. Insulin pumps can provide diabetic patients with continuous insulin infusion at various rates that more closely match the function and behavior of a properly functioning pancreas in non-diabetic patients, thus helping diabetic patients maintain blood glucose levels within a target range based on their individual needs.

[0006] Infusion pump therapy requires an infusion cannula, usually in the form of an infusion needle or flexible catheter, which penetrates the skin of a diabetic patient and delivers insulin. Infusion pump therapy offers the advantages of continuous insulin delivery, precise dosing, and a programmable delivery schedule.

[0007] In intravenous therapy, insulin doses are typically administered at a basal rate and as bolus doses. When insulin is administered at a basal rate, it is delivered continuously over 24 hours, maintaining the blood glucose levels of diabetic patients within a consistent range between meals and rest, typically during the night. Insulin pumps can also be programmed to vary the basal rate of insulin according to different times of day and night. In contrast, bolus doses are typically administered when a diabetic patient eats a meal and generally provide a single additional insulin injection to balance the carbohydrates consumed. Insulin pumps can be configured to allow diabetic patients to program the volume of bolus doses according to the size or type of meal consumed by the diabetic patient. In addition, insulin pumps can also be configured to allow the infusion of corrective or supplemental bolus doses of insulin to compensate for low blood glucose levels when calculating the bolus dose for a particular meal consumed by the diabetic patient.

[0008] Insulin pumps offer the advantage of delivering insulin over time compared to single injections, typically resulting in less fluctuation within the recommended blood glucose range. In addition, insulin pumps can improve diabetes management by reducing the number of needle sticks that diabetic patients must endure, thereby improving their quality of life.

[0009] Typically, diabetic patients, regardless of whether they use multidrug injectors (MDIs) or blood pumps, measure their fasting blood glucose (FBGM) upon waking from sleep, and also measure their blood glucose levels with or after each meal to determine if corrective medication is needed. In addition, diabetic patients may also test their blood glucose levels before sleep to determine if corrective medication is needed, for example, after eating a light meal before sleep.

[0010] To facilitate infusion therapy, there are generally two types of insulin pumps: conventional pumps and patch pumps. Conventional pumps typically require the use of disposable components called infusion sets, tubing sets, or pump sets, which deliver insulin from a reservoir in the pump into the user's skin. An infusion set consists of a pump connector, a tube of a certain length, and a hub or base from which a cannula, in the form of a hollow metal infusion needle or a flexible plastic catheter, extends. The base typically has an adhesive that holds the base on the skin surface during use. The cannula can be inserted into the skin manually or using a manual or automated insertion device. The insertion device may be a separate unit used by the user.

[0011] Another type of insulin pump is the patch pump. Unlike the conventional combination of infusion pump and infusion set, a patch pump is an integrated device that combines most or all of the fluid components, including the fluid reservoir, pump mechanism, and mechanism for automatic cannula insertion, into a single housing that adheres to the injection site on the patient's skin, eliminating the need for a separate infusion or tubing set. The insulin-containing patch pump adheres to the skin and delivers insulin for a set period of time via a built-in subcutaneous cannula. Some patch pumps communicate wirelessly with a separate controller device (like one device marketed by Inslet under the brand name OmniPod®), while others are completely self-contained. Such devices are replaced frequently, such as every three days, when the insulin reservoir is drained or when complications such as cannula or injection site limitations may occur.

[0012] Since patch pumps are designed to be self-contained units worn by diabetic patients, it is preferable to make them as small as possible so as not to interfere with the user's activities. Therefore, it is preferable to minimize the overall thickness of the patch pump to minimize user discomfort. However, in order to minimize the thickness of the patch pump, its components must be made as small as possible. One such component is the insertion mechanism for automatically inserting the cannula into the user's skin.

[0013] To minimize the height of the insertion mechanism, some conventional insertion mechanisms are configured to insert the cannula at a sharp angle from the skin surface, for example, 30-45 degrees. However, because this requires a minimum length of cannula insertion, it may be preferable to insert the cannula perpendicular to or nearly perpendicular to the skin surface. In other words, when the minimum length of cannula is inserted into the user's skin, the user can experience greater comfort and fewer complications, such as premature twisting of the cannula. However, one problem with cannula insertion is determining whether the cannula is fully inserted into the skin surface.

[0014] Therefore, an improved insertion mechanism is needed for use in confined spaces such as patch pumps, which can minimize or reduce its height and allow the cannula to be inserted vertically or close to the user's skin, while indicating that the cannula is fully inserted into the skin surface. [Overview of the project]

[0015] In a first embodiment, the catheter insertion device includes a housing, a button including a body and at least one arm extending from the body into the housing and movably coupling the button to the housing, a button movable between an elevated position and a lowered position, and a needle hub coupled to the button to move together with the button between the elevated position and the lowered position. In the elevated position, the body of the button is at a first distance from the needle hub, reducing visibility of the needle hub through the body of the button. In the lowered position, the body of the button is at a second distance from the needle hub that is shorter than the first distance that allows visibility of the needle hub through the body of the button.

[0016] In a second embodiment, the catheter insertion device includes a needle hub and a button comprising a body that is movable relative to the needle hub and defines a cavity shaped to be complementary to the shape of the needle hub, wherein the body has opacity that limits the visibility of the needle hub through the body when the needle hub is separated from the cavity and allows the needle hub through the body to be visible when the needle hub is at least partially positioned within the cavity.

[0017] In a third embodiment, the catheter insertion device includes a button comprising a body having a first part and a second part, wherein the first part is a button having an opacity less than the opacity of the second part, and a needle hub movable relative to the button, the needle hub including an indicator that is visible through the second part and not visible through the first part when the needle hub is at a first distance from the body of the button, and when the needle hub is at a second distance from the body of the button, the indicator is visible through both the second part and the first part, wherein the second distance is less than the first distance.

[0018] In a fourth embodiment, the catheter insertion device includes a housing, a button comprising a body for movably coupling the button to the housing, and at least one arm extending from the body into the housing, wherein the button is movable between an elevated position and a lowered position, and a needle hub movable relative to the button, the needle hub including an indicator visible in the lowered position through the body of the button.

[0019] These and additional features provided by the embodiments described herein will be better understood in conjunction with the drawings and the following detailed description. [Brief explanation of the drawing]

[0020] The embodiments shown in the drawings are illustrative in nature and are not intended to limit the subject matter defined by the claims. The following detailed description of the exemplary embodiments can be understood in conjunction with the following drawings, and similar structures are indicated by the same reference numerals. [Figure 1] Figure 1 is an isometric view of an insertion device in a pre - operation state according to an embodiment of the present invention. [Figure 2] Figure 2 is an isometric view of the insertion device of Figure 1 in an after - operation state according to an embodiment of the present invention. [Figure 3] Figure 3 is an exploded view of the insertion device of Figure 1 according to an embodiment of the present invention. [Figure 4] Figure 4 is an exploded view of the button sub - assembly 30 of the insertion device of Figure 1, including the catheter / separator sub - assembly 10 and the introducer needle sub - assembly 20, according to an embodiment of the present invention. [Figure 5] Figure 5 is a view of the completed button sub - assembly 30 of Figure 4 according to an embodiment of the present invention. [Figure 6] Figure 6 is an exploded view of the insertion device and the button sub - assembly 30 of Figure 5, showing the use of a temporary protection tube on a catheter with a spring inside the housing of the insertion device, according to an embodiment of the present invention. [Figure 7A] Figure 7A is a cross - sectional view of the insertion device of Figure 1 in a pre - operation state according to an embodiment of the present invention. [Figure 7B] Figure 7B is another cross - sectional view of the insertion device of Figure 1 in a pre - operation state according to an embodiment of the present invention. [Figure 8] Figure 8 is a perspective view of the insertion device of Figure 1 in a pre - operation state, showing the position of a radial operation pin in a spiral path, according to an embodiment of the present invention. [Figure 9] Figure 9 is a perspective view of the insertion device of Figure 1 in an intermediate operation state, showing the position of a radial movement pin, according to an embodiment of the present invention. [Figure 10] Figure 10 is a cross - sectional view of the insertion device of Figure 1 in an after - operation state according to an embodiment of the present invention. [Figure 11] Figure 11 is a perspective view of the insertion device of Figure 1 in an after - operation state, showing the position of a radial operation pin at full retraction, according to an embodiment of the present invention. [Figure 12]FIG. 12 is a perspective view of a patch pump incorporating a low-profile cannula insertion device shown without a cover for clarity. [Figure 13] FIG. 13 is an exploded view of the various components of the patch pump of FIG. 12 shown with a cover. [Figure 14] FIG. 14 is a perspective view of an alternative design of a patch pump having a flexible reservoir shown without a cover. [Figure 15] FIG. 15 is a patch pump fluid architecture and metering subsystem diagram of the patch pump of FIG. 14.

DETAILED DESCRIPTION OF THE INVENTION

[0021] The exemplary embodiments of the invention described below provide new means for inserting a catheter into a user's skin and providing one or more infusion device elements configured to indicate when the catheter is fully inserted into the skin, but the embodiments are not limited thereto. The insertion device is configured to perform manual insertion of the catheter, whereby the insertion device is smaller, simpler, and less expensive than an automatic or spring-assisted insertion device.

[0022] The exemplary embodiments of the present invention described below utilize a manual insertion device and include a dual retraction spring configuration for automated guided needle retraction, enabling a very small device size. The dual retraction spring configuration is implemented using multiple cylindrical or barrel-shaped guides. In the exemplary embodiment, one barrel guides the button and catheter, and adjacent barrels house one retraction spring on each side of the button and catheter. Having the springs in separate barrels allows for much smaller springs than a single-barrel configuration where the spring is coaxial with the catheter. A single coaxial spring, due to spring design limitations, requires the spring to extend almost from the bottom to the top of the housing, thus allowing access to the button assembly. Features such as lock arms require access, and if the features are implemented within the spring, the entire mechanism needs to grow to accommodate them, increasing the footprint of the mechanism.

[0023] Figure 1 shows the insertion device before use, and Figure 2 shows the device after the cannula has been deployed. The insertion device includes an upper housing 100 and a base 102. The upper housing 100 is shown to have an opening 104 through its upper surface from which a user-accessible and user-operable button 200 slides. The contents of the insertion device, including the mechanism housing 300, are shown in more detail in Figure 3. The upper housing 100, the button 200, and the mechanism housing 300 can be manufactured from ABS, and the base 102 can be manufactured from PETG, but the embodiments are not limited thereto.

[0024] As shown in Figure 3, the exemplary insertion device is assembled by stacking several subassemblies together, which are trapped between the upper housing 100 and the mechanism housing 300. The subassemblies shown in Figure 3 and described in more detail below include the catheter / septum subassembly 10, the introduction needle subassembly 20, and the button subassembly 30. Other features and functions of the insertion device, which are well known to those skilled in the art, are omitted from the drawings and description for clarity.

[0025] An exemplary button subassembly 30 is shown in Figure 4, including the catheter / septum subassembly 10 and the introduction needle subassembly 20, and Figure 5 shows the completed button subassembly 30 of the insertion device of Figure 1 according to one embodiment of the present invention. The button subassembly is constructed by combining the catheter / septum subassembly and the introduction needle subassembly with a button 200. Once assembled, as will be described in more detail below, the introduction needle subassembly 20 cannot be rotated on the button 200. The catheter / septum subassembly 10 can be rotated within the button 200, in which case it can be rotated from a position fixed to the introduction needle subassembly 20 to a position free from the introduction needle subassembly 20. For example, the button subassembly 30 may be movable between a pre-operational state (Figure 8), an intermediate state (Figure 9), and a post-operational state (Figure 11), where in the pre-operational state the button 200 of the button subassembly 30 is in the raised position, in the intermediate state the button 200 is in the intermediate position, and in the post-operational state the button 200 is in the lowered position. Each of the states and positions is described in more detail below.

[0026] Specifically, according to one embodiment, the button subassembly 30 is constructed by inserting the introduction needle 222 of the introduction needle subassembly 20 through the septum 206 and catheter 202 of the catheter / septum subassembly 10 or catheter hub 10. The catheter / septum subassembly 10 is then secured to the introduction needle subassembly 20 by rotating the catheter / septum subassembly 10 by up to approximately 20 degrees or more, and locking the retainer or teeth 238 on the release collar 208 into a groove, slot, or retainer 240 on the upper surface of the introduction needle hub 224, thereby coupling the introduction needle hub 224 and the catheter / septum subassembly 10. In this position, the teeth 238 are locked to the top of the introduction needle hub 224 such that the button 200 is pressed down and the introduction needle hub 224 also moves downward. This moves the introduction needle 222 and catheter 202 simultaneously for insertion into the user's skin (not shown). Selective coupling of the needle hub 224 to the collar 208 through engagement with the teeth 238 allows for movement of the catheter / septum subassembly 10 with respect to the needle hub 224 and the button 200.

[0027] Next, the button subassembly 30 is completed by snapping the release collar 208 onto the button 200 to secure the introduction needle subassembly 20 and the catheter / septum subassembly 10 in place. To this end, the button 200 includes a stopper 212 on a deflectable arm 214, as shown in Figure 5, which can deflect between them and then capture the lower edge of the release collar 208. Between the deflectable arms 214, a slot 216 is provided in the button 200, allowing linear movement of the introduction needle hub 224 relative to the button 200, but prohibiting rotational movement of the introduction needle hub relative to the button 200. The slot 216 in the button 200 also allows rotational movement of the radial operating pin 218 of the release collar 208 relative to the button 200, as will be described in more detail below. In an exemplary embodiment, a substantially cylindrical pin 218 is shown on the outer circumference of the release collar 208. However, in this or other embodiments of the present invention, any stopper or projection of the release collar that can operate with the helical path can be provided as a radially acting pin.

[0028] Next, the button subassembly 30 can be assembled with the upper housing 100 and the mechanism housing 300. Figure 6 shows the assembly of the button subassembly 30 and the spring to the housing of the insertion device in Figure 1, and the use of a temporary protective tube on the catheter. To complete the assembly, the button 200 and its assembly are assembled to slide together with a projection 106 extending from the inner surface of the upper housing 100, as shown in more detail in Figure 7A. Figure 7A is a cross-sectional view of the fully assembled insertion device in Figure 1 in a pre-operation state according to an embodiment of the present invention. The button lock arm 112 of the upper housing 100 holds the button subassembly 30 in place during the next assembly step of placing the mechanism housing 300 into the upper housing 100, thereby trapping the other subassemblies therein.

[0029] The mechanism housing 300 preferably comprises three cylinders, guides, or barrels, including a central barrel 302 that slidably receives and guides the button subassembly 30, and two barrels 304, one on each side of the central barrel 302, that restrain the spring 230. During assembly, the spring 230 is trapped between the boss 242 of the introduction needle hub 224 and the bottom of the barrel 304 of the mechanism housing 300. In doing so, the spring 230 exerts an expansion force between the introduction needle hub 224 and the bottom of the barrel 304 of the mechanism housing 300. In exemplary embodiments, multiple springs 230 and adjacent barrels 304 are shown. However, in this or other embodiments of the invention, a single spring and adjacent barrels can be provided in substantially the same manner, and unused adjacent barrels can be left empty or omitted entirely. Furthermore, a single spring may be provided at the top of the button, extended during insertion, and retracted to its natural state upon completion, thereby retracting the introduction needle from the catheter.

[0030] The rounded boss 242 has a diameter and length to center and align the spring 230 during operation. The spring 230 may be partially pre-pressurized during the assembly of the insertion device, and the mechanism housing 300 may be laser-welded or bonded to the upper housing 100. A bottom or base 102 can then be added. In this way, as the final assembly step, a full and complete insertion mechanism subassembly can be placed on the base 102 along with all the other components. Having a completed insertion mechanism subassembly makes handling during production easier rather than having all the parts confined between the upper and lower housings. In an exemplary manufacturing, the mechanism housing 300 is attached to the upper housing 100 using snaps or adhesive (not shown) that hold the mechanism together.

[0031] Referring further to Figure 7A, a fully assembled insertable device is shown in a pre-operational state according to one embodiment of the present invention. As shown in Figure 7A, the arm 214 of the button 200 extends into the housing 100 from the lower side 203 of the body 201 of the button 200, movably coupling the button 200 to the housing 100, allowing the button 200 to move between an up position and a down position (Figure 10). The body 201 may include a first portion 205 and a second portion 207 on the upper side 209 opposite the lower side 203 of the body 201, with the first portion 205 having less opacity than the second portion 207. However, it is intended and possible for the first portion 205 and the second portion 207 to each have the same opacity. The first portion 205 may be formed by any conventional method or material to increase the opacity of the body 201, such as frosted plastic or glass, bruting, etc. As used herein, brutting is a process of increasing surface roughness to increase opacity, for example, by sanding. The body 201 may be formed on the underside 203 of the button 200 and shaped to complement the shape of the needle hub 224, defining a cavity 211 configured to at least partially enclose the needle hub 224 in the lowered position.

[0032] The first portion 205 may have opacity that limits the visibility of the needle hub 224 through the body 201 when the needle hub 224 is separated from the cavity 211, and allows the needle hub 224 to be visible through the body 201 when the needle hub 224 is at least partially positioned within the cavity 211. The first portion 205 is at least partially positioned directly opposite the cavity 211 such that the needle hub 224 is visible through the first portion 205 when the needle hub 224 is at least partially positioned within the cavity 211. As will be described in more detail below, the needle hub 224 may be positioned within the cavity 211 when the button 200 is in the lowered position (Figure 10). The first portion 205 may be positioned closer to the cavity 211 than the second portion 207 such that when the needle hub 224 is positioned within the cavity 211, the needle hub 224 is visible only through the first portion 205 and not through the second portion 207. In other words, the orthographic projection of the cavity 211 extending perpendicularly through the lower part 203 intersects the first part 205 at least partially.

[0033] As described above, the needle hub is coupled to the button so as to move with the button between an elevated position and a lowered position. As shown in Figure 7A, the needle hub includes a base 213 and an indicator 215 extending from the base 213 toward the lower side 203 of the body 201 of the button 200. The indicator 215 may be formed of a material and may include a color or marking such that the second distance d2 is less than the first distance d1, and is visible through the second portion 207 and not through the first portion 205 when the needle hub 224 is at a second distance d2 from the body 201 of the button 200, and is visible through both the second portion 207 and the first portion 205. The indicator 215 may be visible through the body 201 of the button 200 only when the button 200 is in the lowered position.

[0034] Referring to Figures 7A and 7B, according to one embodiment, one or more breakable ribs 236 on the activation button 200 (Figures 4 and 5) are captured by a step return stopper 110 in the upper housing 100 to hold the button 200 in a pre-activation state. A safety tab (not shown) may also be placed in the button slot to prevent accidental activation during shipping and handling of the device once the device is removed from the package. The safety tab is removed immediately before insertion.

[0035] Referring to Figures 7A to 8, in the pre-operation state where the button 200 is in the raised position, the body 201 of the button 200 is separated from the needle hub 224 by a first distance d1. As will be described in more detail below, when the body 201 of the button 200 is separated from the needle hub 224 by a first distance d1, the body 201 restricts the visibility of the needle hub 224 through the body 201 so that the needle hub 224 is not clearly visible through the body 201.

[0036] To activate the device, the user presses button 200 into the upper housing 100. When the ribs 236 break or exceed the deformation force threshold, the three ribs 236 yield, and button 200 abruptly inserts the introduction needle 222 and catheter 202 downward, loading the retraction spring 230. The spring 230 can be partially pre-compressed during the assembly of the insertion device. The minimum breaking force of the breakable ribs 236 ensures that the user presses hard enough to fully insert the catheter. Partial action results in the catheter not being fully inserted, the introduction needle not retracting, and the catheter not locking into the post-action position.

[0037] The release of button 200 from rib 236 is configured to occur when a desired amount of actuation force is applied to button 200. Since button 200 is releasably held in the raised position by the engagement between rib 236 and step stopper 110, the force applied to button 200 by the user steadily increases over a period of time before release. Upon sudden release, the force on button 200 has reached the desired value, and therefore button 200 is accelerated downward due to the sudden freedom of movement and the desired force applied to button 200 upon release and subsequently maintained. Such release ensures that a desired amount of downward force, velocity, smoothness, and angle is applied by the user. Such actuation substantially eliminates variations in the applied user force, velocity, smoothness, and angle, reducing insertion failure and / or discomfort to the user.

[0038] Referring to Figures 9 to 11, after the release of the button 200, the button subassembly 30 and its components begin to move through the mechanism housing 300. One of the two teeth 238 on the release collar 208 (see, for example, Figure 4) connects the introduction needle hub 224 to the catheter / septum subassembly 10. In this position, the tooth 238 locks over the top of the introduction needle hub 224 so that the button 200 is pressed down and the introduction needle hub 224 also moves downward. When the button 200 is pressed down, the introduction needle hub 224 also moves downward, resulting in the introduction needle 222 and catheter 202 being inserted simultaneously into the user's skin (not shown), and the introduction needle hub 224 compressing the spring 230, or biasing member 230 that engages with the needle hub 224. When compressed, the spring 230 biases the needle hub 224 toward the body 201 of the button 200. To create an insertion device with a small footprint, each of the springs 230 has a small diameter relative to the compression length, which would cause the spring to buckle during compression if it were not supported. A boss 242 on the guide needle hub 224 translates through the center of the spring 230 during compression to prevent the spring 230 from buckling. In an exemplary embodiment, the spring 230 is compressed and exerts an expansion force to retract the guide needle hub and guide needle. However, in this or other embodiments of the invention, one or more extension springs may be used to exert a retraction force to retract the guide needle hub and guide needle.

[0039] As described above, the catheter / septum subassembly 10 is attached to the button 200 and the introduction needle hub 224, but is free to rotate about 20 degrees around the primary axis. In this case, the primary axis is defined as the axis extending along the geometric center of the insertion needle 222. A slot 216 is provided in the button 200, allowing linear movement of the introduction needle hub 224 relative to the button 200, but prohibiting rotational movement of the introduction needle hub relative to the button 200. The slot 216 in the button 200 also allows rotational movement of the radial operating pin 218 of the release collar 208 relative to the button 200. The angle of this rotation is controlled by the radial operating pin 218 extending from the release collar 208. During insertion, i.e., during the downward movement of the button subassembly 30, the radial operating pin 218 moves along the helical path 400, or slot 400, defined by the housing 100 and created by the combined features in the upper housing 100 and the mechanism housing 300. During such movement, as the catheter hub 10 moves with the button 200 between the raised and intermediate positions, the radial operating pin 218 of the release collar 208 rotates or pivots the release collar 208 of the catheter hub 10, ultimately releasing the insertion needle subassembly 20 from the catheter / septum subassembly 10 when the button 200 is in the intermediate position. The surface 108 in the upper housing 100 and the surface 308 in the mechanism housing 300 that create the helical path 400 are divided between two parts, so that both parts can be molded without a slide. That is, by creating the helical path 400 using the joining of two separately molded parts, a single part having a molded slide or path in it is not required, greatly simplifying the manufacture of the insertion device. Figures 8, 9, and 11 show the surface 108 in the upper housing 100 and the surface 308 in the mechanism housing 300 that create the helical path 400 when assembled.

[0040] As described above, the slot 216 in the button 200 allows the radial operating pin 218 of the release collar 208 to move. Furthermore, the catheter / septum subassembly 10, which is attached to the button 200 and the introduction needle hub 224, can rotate freely up to 20 degrees around its primary axis. Such a 20-degree rotation allows the radial operating pin 218 of the release collar 208 to move along the helical path 400. When the button 200 is pressed down, the release collar 208 and its radial operating pin 218 move downward through the stationary upper housing 100 and mechanism housing 300. Thus, the radial operating pin 218 of the release collar 208, which is slidably positioned in the helical path 400, rotates the release collar as it moves downward through the stationary upper housing 100 and mechanism housing 300 by the button 200.

[0041] In the pre-operation state, the angle of the radial operating pin 218 is constrained in a direction in which the teeth 238 of the release collar 208 fully engage with the introduction needle hub 224. While the button 200 moves between the pre-operation and post-operation states, the radial operating pin 218 of the release collar 208 rotates the release collar 208 as it moves through the helical path 400 of the stationary upper housing 100 and mechanism housing 300.

[0042] In the activated state, the radial operating pin 218 is rotated to approximately 20 degrees, which disengages the introduction needle hub 224 from the teeth 238 of the release collar 208, releasing the introduction needle hub 224 from the release collar 208 and allowing it to be retracted by the compression spring 230. The release collar 208 and the other elements of the catheter / septum subassembly 10 are left in the lower insertion position.

[0043] Figure 9 shows the insertion device during insertion of the introduction needle 222 and catheter 202, in an intermediate position just before the introduction needle hub 224 is released by the radial operating pin 218 of the release collar 208 for retraction. In the intermediate position, the button 200 is in an intermediate position between the raised position (Figures 7 and 8) and the lowered position (Figures 10 and 11). In the intermediate position, with the button 200 in the intermediate position, the introduction needle 222 and catheter 202 extend from the housing 100 and are inserted into the user's skin, but before the needle hub 224 retracts relative to the button 200. In this position, the catheter 202 surrounds the needle 222 which is extended by the needle 222 in the intermediate position. When moving from the raised position to the intermediate position, the needle 222 moves with the button 200 and extends from the housing 100, and when moving from the intermediate position to the lowered position, the needle 222 retracts toward the lower side 203 of the body 201 of the button 200.

[0044] In the intermediate state, the radial operating pin 218 and the release collar 208 rotate almost completely by engaging with the helical path 400. At the end of the rotation by the helical path 400, the teeth 238 on the release collar 208 are about to move free from the retaining arm 240 of the guide needle hub 224 (see, for example, Figures 4 and 5), releasing the guide needle hub 224 so that the spring 230 can push the guide needle hub 224 up and retract it. That is, as the radial operating pin 218 and the release collar 208 rotate by engaging with the helical path 400, the teeth 238 on the release collar 208 rotate simultaneously until they are free from the retaining arm 240 of the guide needle hub 224.

[0045] At this point, the release collar 208, held by the button 200, is no longer fixed to the introduction needle hub 224, and the spring 230 pushes the introduction needle hub 224 and introduction needle 222 into an upward retracted position, leaving the catheter / septum subassembly 10 in the downward insertion position. The button 200 locks into the downward position, thereby holding the catheter / septum subassembly 10 in the downward insertion position. A locking arm 112 protruding from the upper housing 100, which holds the button subassembly 30 in place during assembly, may also be configured to snap into a retaining arm 244 within the button 200 in the post-operated state, locking the button subassembly 30 in place and holding the catheter in place against the skin.

[0046] Referring further to Figure 9, the retraction spring 230 is fully compressed, and the radial operating pin 218 and release collar 208 are rotated to the extent necessary to disengage the teeth 238 of the release collar 208 from the introduction needle hub 224 in order to release the introduction needle hub 224 for retraction.

[0047] Referring to Figures 10 and 11, the insertion device is shown in the post-activation state with the button 200 in the lowered position. In the post-activation state, the button 200 is fully pressed down to the lowered position using the catheter 202 placed on the user's skin. The biasing member 230 biases the introduction needle 222 to retract further into the housing 100 than its pre-activation state to ensure that needle sticks are blocked and the catheter 202 is protected from damage. The tip of the introduction needle 222 remains sealed by the partition 206 in the fluid path to form a continuous fluid path with the catheter 202. In this embodiment or other embodiments, the tip or distal portion of the introduction needle 222 remains inside the catheter 202. When the introduction needle 222 retracts into the housing 100, the needle hub 224 is retracted toward the body 201 of the button 200, with the indicator 215 at least partially positioned within the cavity 211 of the button 200 so that it is visible through the body 201. When button 200 is in the lowered position, the body 201 of button 200 is at a second distance d2 from the needle hub 224, the needle hub 224 is adjacent to the body 201, and the second distance d2 is smaller than the first distance d1, which allows the needle hub 224 to be seen through the body 201 of button 200. As shown in Figure 11, when the insertion device is in the post-startup state, the indicator 215 is visible through the body 201 of button 200.

[0048] In exemplary embodiments, manual insertion of the introduction needle and catheter makes the insertion device smaller, easier, and less expensive than insertion devices using spring-assisted insertion. Other patch pump plastic catheter insertion mechanisms use a larger insertion spring relative to the retraction spring because the insertion force is greater than the retraction force. Fully integrated spring-assisted insertion also allows for angled insertion of low-profile devices, increasing the stroke and significantly increasing the size of the wound and mechanism. The insertion spring serves no purpose after insertion and simply occupies space within the device where size is one of the most important user requirements of the product.

[0049] In exemplary embodiments, a dual retraction spring configuration also allows for a very small size. One barrel of the insertion device housing guides the button and catheter, while the adjacent barrel houses the two retraction springs. Having the springs in separate barrels and oriented by a boss on the introduction needle hub allows for a much smaller spring than a single-barrel configuration where the spring is coaxial with the catheter. A single coaxial spring, due to spring design limitations, requires the spring to extend almost from the bottom to the top of the housing, thus allowing access to the button assembly. Features such as a locking arm require access, and if the feature is implemented within the spring, the entire mechanism needs to grow to increase the footprint of the mechanism. Passively locking the catheter downwards to retract the introduction needle creates the simplest possible manual insertion user interface for a manual insertion mechanism that is a single button press.

[0050] As mentioned above, the retraction spring 230 is minimally loaded before use to ensure that the insertion needle 222 is fully retracted into the device. The spring 230 is further loaded during insertion. Providing the insertion device with a minimally loaded spring rather than a fully loaded spring reduces the risks associated with sterilizing and storing a loaded spring and simplifies the design.

[0051] To operate the insertion device, the user applies the insertion device to the user's skin using the adhesive on the device base 102. The user then manually presses the ejection button 200 until the rib 236 is broken or deformed. The button 200 is now suddenly free to move and is rapidly pushed into the upper housing 100, helping to push the plastic catheter 202 and introduction needle 222 into the user's skin. While the button 200 is pressed, the release collar 208 is rotated by the radial operating pin 218 of the release collar 208, which moves through the helical path 400. The release collar 208 is rotated to the extent required to detach the release collar 208 from the introduction needle hub 224, and the introduction needle hub 224 and introduction needle 222 are then retracted beyond the original needle position to ensure needle shielding. Here, the plastic catheter 202, detached from the introduction needle 222, is left in the lower insertion position. Button 200 automatically locks in a downward position at the same height as the top of the housing, which also locks the catheter at a desired depth in the subcutaneous layer, for example. A sensor (not shown) may be provided to detect the post-operation state and advise other electronic devices (not shown) that the catheter has been properly inserted, which allows the patient to inject the medication. A pump or reservoir then injects the medication into the catheter via the introduction needle and from there into the patient's subcutaneous layer. To best target the desired depth, the base may include skin interface geometry to achieve and maintain the desired insertion depth, avoid skin tensing, and / or stretch the skin at the insertion site.

[0052] In the embodiments described above, the patch pump may comprise one or more of the described features. Figure 12 is a perspective view of an exemplary embodiment of patch pump 1 according to an exemplary embodiment of the present invention. Patch pump 1 is illustrated with a see-through cover for clarity and shows the various components assembled to form patch pump 1. Figure 13 is a diagram of the various components of patch pump 12, shown with a solid cover 2. The various components of patch pump 1 may include a reservoir 4 for storing insulin, a pump 3 for pumping insulin from reservoir 4, a power supply 5 in the form of one or more batteries, an insertion mechanism 7 for inserting an insertion needle with a catheter into the user's skin, control electronics 8 in the form of a circuit board having optional communication capabilities to external devices such as a remote controller including a smartphone and a computer, a dose button 6 on cover 2 for activating insulin administration including bolus administration, and a base 9 to which the various components described above can be attached via fasteners 91. Patch pump 1 also includes various fluid connector lines for transferring insulin pumped from reservoir 4 to the injection site.

[0053] As mentioned above, it should be understood that insertion mechanisms can have various configurations. In some embodiments, the insertion mechanism inserts a soft catheter into the skin. In these embodiments, the soft catheter is typically supported by a rigid insertion needle. The insertion needle is inserted into the skin together with the soft catheter, then retracts from the skin, leaving the soft catheter in the skin. In other embodiments, no soft catheter is provided, and the insertion needle remains in the skin, forming part of the insulin channel for delivering insulin until the infusion is complete. The insertion needle is typically hollow and must be hollow if they form part of the insulin channel. However, an insertion needle that supports a soft catheter and then retracts can be solid or hollow. If the insertion needle deploys and then retracts the soft catheter but forms part of the insulin channel, the insertion needle should be hollow. However, if the insertion needle deploys and then retracts the soft catheter but does not form part of the insulin channel, the insertion needle can be solid or hollow. In any case, it is preferable that the insertion needle is rigid enough to reliably penetrate the skin, but if not, it may be flexible enough to provide comfort to the user.

[0054] Figure 14 is a perspective view of an alternative design of patch pump 1A, which has a flexible reservoir 4A and is shown without a cover. Such a configuration may further reduce the external dimensions of patch pump 1A by having the flexible reservoir 4A fill the void within patch pump 1A. Patch pump 1A is typically shown using a conventional cannula insertion device 7A that inserts the cannula at an acute angle of less than 90 degrees on the surface of the user's skin. Patch pump 1A further comprises a power supply 5A in the form of a battery, a measurement subsystem 41 that monitors the volume of insulin and includes low-volume detection capability, control electronics 8A for controlling the components of the device, and a reservoir filling port 43 for receiving a refill syringe 45 for filling reservoir 4A.

[0055] Figure 15 is a diagram of the patch pump fluid architecture and metering subsystem of patch pump 1A of Figure 14. The power storage subsystem for patch pump 1A includes a battery 5A. The control electronics 8A of patch pump 1A may include a microcontroller 81, sensing electronics 82, pump and valve controller 83, sensing electronics 85, and deployment electronics 87, which control the operation of patch pump 1A. Patch pump 1A includes a fluid subsystem which may include a reservoir 4A, a volume sensor 48 for reservoir 4A, and a reservoir filling port 43 for receiving a refill syringe 45 to replenish reservoir 4A. The fluid subsystem may include a metering system which includes a pump and valve actuator 411 and an integrated pump and valve mechanism 413. The fluid subsystem may further include an occlusion sensor 49, a deployment actuator 7, and a cannula 47 for insertion into the injection site on the user's skin. The patch pump architectures of Figures 12 and 13 are identical or similar to those shown in Figure 15.

[0056] Although only a few exemplary embodiments of the present invention have been described in detail above, those skilled in the art will readily understand that many modifications are possible in the exemplary embodiments without substantially departing from the novel teachings and merits of the present invention. Any of the embodiments and / or elements disclosed herein can be combined with each other to form a variety of additional embodiments not specifically disclosed, insofar as they do not contradict each other. Those skilled in the art should take particular note that various technical aspects of various elements of the various exemplary embodiments described above can be easily combined in many other ways, all of which are considered to be within the scope of the present invention and are defined by the appended claims and their equivalents.

Claims

1. A catheter insertion device, Housing and A button comprising a body and at least one arm extending from the body into the housing and movably connecting the button to the housing, wherein the button is movable between an up position and a down position, A needle hub is coupled to the button so as to move between the raised position and the lowered position together with the button, Equipped with, In the raised position, the body of the button is at a first distance from the needle hub that reduces the visibility of the needle hub passing through the body of the button. A catheter insertion device wherein, in the lowered position, the body of the button is at a second distance from the needle hub, the second distance being smaller than the first distance, and the needle hub is visible through the body of the button.

2. The catheter insertion device according to claim 1, wherein the button defines a cavity configured to at least partially surround the needle hub in the lowered position.

3. The catheter insertion device according to claim 2, wherein the body of the button comprises a first portion and a second portion, the first portion being positioned closer to the cavity than the second portion and having an opacity less than that of the second portion.

4. The catheter insertion device according to claim 2, wherein the needle hub comprises a base, a needle extending from the base, and an indicator extending from the base on the opposite side of the needle, the indicator being at least partially positioned within the cavity in the lowered position.

5. The aforementioned button is movable to an intermediate position between the raised position and the lowered position. When moving from the raised position to the intermediate position, the needle moves together with the button and extends from the housing. The catheter insertion device according to claim 4, wherein when the needle moves from the intermediate position to the lowered position, the needle retracts toward the body of the button, and the indicator is positioned within the cavity of the body.

6. The catheter insertion device according to claim 5, further comprising a biasing member that engages with the needle hub and biases the needle hub toward the body of the button.

7. The catheter hub further comprises a collar, teeth extending from the collar, and a pin extending from the collar, wherein the needle hub is selectively coupled to the catheter hub through engagement with the teeth to allow movement of the catheter hub with respect to the needle hub and the button. The pin engages with a slot defined by the housing that pivots the catheter hub when the catheter hub moves together with the button between the raised position and the intermediate position. The catheter insertion device according to claim 5, wherein in an intermediate position, the catheter hub is pivoted relative to the needle hub, thereby detaching the needle hub from the catheter hub and allowing the needle hub to move toward the body of the button.

8. The catheter hub further comprises a catheter extending from the collar, the catheter surrounding the needle at the raised position and the intermediate position, and at the intermediate position, both the needle and the catheter extend from the housing. The catheter insertion device according to claim 7, wherein in the lowered position, the catheter extends from the housing, and the needle is retracted into the housing with the needle hub positioned within the cavity of the main body.

9. A catheter insertion device, Needle hub and, A catheter insertion device comprising: a button having a body that is movable relative to the needle hub and defines a cavity configured to at least partially surround the needle hub in the lowered position, wherein the body has an opacity that restricts the needle hub from being visible through the body when the needle hub is separated from the cavity, and allows the needle hub to be visible through the body when the needle hub is at least partially positioned within the cavity.

10. The catheter insertion device according to claim 9, wherein the body of the button comprises a first portion and a second portion, the first portion being positioned adjacent to the cavity and having an opacity less than that of the second portion.

11. The catheter insertion device according to claim 9, wherein the needle hub comprises a base, a needle extending from the base, and an indicator extending from the base on the opposite side of the needle, the indicator being at least partially configurable within the cavity.

12. The catheter insertion device according to claim 11, wherein the button is movable from an elevated position to an intermediate position and from the intermediate position to a lowered position, the intermediate position being between the elevated position and the lowered position, and when moving from the elevated position to the intermediate position, the needle moves so as to extend out of the housing together with the button, and when moving from the intermediate position to the lowered position, the needle retracts toward the body of the button, positioning the indicator within the cavity of the body.

13. The catheter insertion device according to claim 12, further comprising a biasing member that engages with the needle hub and biases the needle hub toward the body of the button.

14. The catheter hub further comprises a collar, teeth extending from the collar, and a pin extending from the collar, wherein the needle hub is selectively coupled to the catheter hub through engagement with the teeth to allow movement of the catheter hub with respect to the needle hub and the button. The pin engages with a slot defined by the housing surrounding the needle hub that pivots the catheter hub when the catheter hub moves together with the button between the raised position and the intermediate position. The catheter insertion device according to claim 12, wherein, in the intermediate position, the catheter hub is pivoted relative to the needle hub, thereby detaching the needle hub from the catheter hub and allowing the needle hub to move toward the body of the button.

15. A catheter insertion device, A button comprising a body having a first part and a second part, wherein the first part has an opacity less than that of the second part, A catheter insertion device comprising a needle hub movable relative to the button, the needle hub including an indicator visible through a second portion when the needle hub is at a first distance from the body of the button, and not visible through the first portion, the indicator visible through both the second portion and the first portion when the needle hub is at a second distance from the body of the button, the second distance being less than the first distance.

16. The catheter insertion device according to claim 15, wherein the body of the button defines a cavity complementary to the shape of the needle hub so as to surround the indicator of the needle hub at least partially.

17. The catheter insertion device according to claim 16, wherein the needle hub further comprises a base and a needle extending from the base to the opposite side of the indicator.

18. The catheter insertion device according to claim 16, wherein the button is movable between a lowered position, an raised position, and an intermediate position between the raised position and the lowered position, and when it moves from the raised position to the intermediate position, the needle moves together with the button so as to extend from the housing, and when it moves from the intermediate position to the lowered position, the needle retracts toward the body of the button so as to position the indicator within the cavity of the body.

19. The catheter hub further comprises a collar, teeth extending from the collar, and a pin extending from the collar, wherein the needle hub is selectively coupled to the catheter hub through engagement with the teeth to allow movement of the catheter hub with respect to the needle hub and the button. The pin engages with a slot defined by the housing surrounding the needle hub that pivots the catheter hub when the catheter hub moves together with the button between the raised position and the intermediate position. The catheter insertion device according to claim 18, wherein in an intermediate position, the catheter hub is pivoted relative to the needle hub, thereby detaching the needle hub from the catheter hub and allowing the needle hub to move toward the body of the button.

20. The catheter hub further comprises a catheter extending from the collar, the catheter surrounding the needle at the raised position and the intermediate position, and at the intermediate position, both the needle and the catheter extend from the housing. In the lowered position, the catheter extends from the housing, the needle is retracted into the housing, and the needle hub is adjacent to the body of the button, as described in claim 19.

21. A catheter insertion device, Housing and A button comprising a body and at least one arm extending from the body into the housing and movably connecting the button to the housing, wherein the button is movable between an up position and a down position, A catheter insertion device comprising: a needle hub movable relative to the button, the needle hub having an indicator that can be seen through the body of the button when in the lowered position;

22. The catheter insertion device according to claim 21, wherein the indicator of the needle hub is visible only through the body of the button when the button is in the lowered position.

Images