Systems and methods for anchoring medical devices

Some embodiments of a medical device anchor system include an anchor device that secures a medical instrument in place relative to a skin penetration point using subcutaneous anchors.

TECHNICAL FIELD

This document relates to devices, systems, and methods for securing the position of a catheter or another medical instrument, for example, at a skin opening.

BACKGROUND

Venous, arterial, and body fluid catheters are commonly used by physicians. For example, such catheters may be used to gain access to the vascular system for dialysis, for introducing pharmaceutical agents, for nutrition or fluids, for hemodynamic monitoring, and for blood draws. Alternatively, catheters can be used for drainage of fluid collections and to treat infection. Alternatively, catheters can contain electrical leads for neuro-stimulation, cardiac pacing, and the like. Following introduction into the patient, the catheter is secured to the patient. In many instances, the catheter is commonly secured to the patient using an adhesive tape on the skin or by suturing a catheter hub to the patient's skin. In other circumstances, the catheter may be secured to the patient using a subcutaneous anchor mechanism (such as an anchor sleeve equipped with anchors that are deployed using an external actuator handle or a separate delivery device). In many cases, the medical practitioner will make efforts to clean the skin area around the catheter insertion site for purposes of a patient's comfort, safety, and improved visualization of the catheter insertion site after the catheter is installed.

SUMMARY

Some embodiments of a medical device anchor system include an anchor device that receives a medical instrument (such as a catheter or the like that is optionally equipped with suture wings) and secures the instrument in place relative to a skin penetration point. For example, the medical anchor device can be configured to releasably mate the suture wings on a hub of a catheter while also providing subcutaneous anchor mechanisms deployable through the skin penetration point that is already occupied by the catheter, thereby reducing or eliminating the need for installing sutures through the suture wings and the patient's skin. Optionally, in some embodiments the anchor device can be adjusted to a folded configuration that aligns the tines of the subcutaneous anchors in a generally side-by-side configuration to facilitate insertion of the anchors through the skin penetration point. Such a configuration may allow the anchor device to be installed after medical instrument is already in place without the need for a second penetration point for the anchor device. In particular embodiments, the anchor device may be configured to simplify the use of the anchor device, make the anchor device more adaptable to use with medical instruments of different sizes, and to facilitate the maintenance and cleaning of the skin tissue at and around the skin penetration point.

Some embodiments described herein include an anchor device for securing the position of a medical instrument. The anchor device may include a retainer body and first and second anchors extending from the retainer body. Optionally, the retainer body may include a first body portion that is pivotably coupled to a second body portion about a longitudinal fold axis. Also, the retainer body may optionally include one or more anchor engagement portions that are configured to releasably receive one or more corresponding apertures defined by a hub of a catheter. The first and second anchors may optionally extend distally from a distal end of the retainer body. Each anchor may include a flexible tine that is deployable in a subcutaneous region to secure the retainer body relative to a penetration point. The first anchor may be coupled to the first body portion and the second anchor may be coupled to the second body portion. Optionally the first body portion of the retainer body may be pivotable relative to the second body portion about the longitudinal fold axis so that the first and second anchors are adjustable from a first configuration in which the flexible tines extend outwardly away from one another to a second configuration in which the flexible tines extend generally in the same direction.

Particular embodiments described herein include an anchor device for securing the position of a medical instrument. The anchor device may include a retainer body comprising a first body portion that is pivotably coupled to a second body portion about a longitudinal fold axis. The retainer body may also include one or more anchor engagement portions being configured to mate with an external structure of a medical instrument to releasably secure the medical instrument to the retainer body. The anchor device may further include first and second anchors that extend distally from a distal end of the retainer body. Each anchor comprising a flexible tine that is deployable in a subcutaneous region to secure the retainer body relative to a penetration point. The first anchor may be coupled to the first body portion, and the second anchor may be coupled to the second body portion. The first body portion of the retainer body may be pivotable relative to the second body portion about the longitudinal fold axis so that the first and second anchors can be adjusted from a first configuration in which the flexible tines extend outwardly away from one another to a second configuration in which the flexible tines extend generally in the same direction.

Further embodiments described herein include a system for securing the position of a medical instrument. The system may include an adapter and an anchor device. The adapter may include a hub portion that is elastically deformable and configured to substantially surround and releasably engage with the outer surface of medical instrument. The adapter may also include a second portion having one or more engagement members extending outwardly from the hub portion. The anchor device may include a retainer body comprising a first body portion that is pivotably coupled to a second body portion. The anchor device may also include one or more anchor engagement portions being configured to releasably couple with the one or more engagement members extending outwardly from the hub portion of the adapter. The anchor device may further include first and second anchors that extend distally from a distal end of the retainer body. Each anchor may include a flexible tine that is deployable in a subcutaneous region to secure the retainer body relative to a penetration point. The first anchor may be coupled to the first body portion, and the second anchor may be coupled to the second body portion. The first body portion of the retainer body may be pivotable relative to the second body portion so that the first and second anchors are adjustable from one another to a removal configuration in which the flexible tines extend generally in the same direction.

Some other embodiments described herein may include a kit of components for securing the position of a catheter relative to a penetration point. The kit may include a sterile package containing two or more adapters having a hub portion with differently shaped or sized longitudinal lumens. Each of the two or more adapters in the sterile package may comprise an elastically deformable material to permit access to the respective longitudinal lumen. Also, each of the two or more adapters in the sterile package may include a one or more flanges extending outwardly away from the hub portion. The hub portion may include a longitudinal slit through a wall portion to permit access to the respective longitudinal lumen. The one or more flanges may each include an adapter engagement portion configured to releasably engage with retention posts of an anchor device.

Additional embodiments described herein may include a kit of components including a sterile package containing an anchor device and a catheter. The catheter may include a hub having one or more apertures configured to releasably mate with the anchor device. The anchor device may include a retainer body including a first body portion that is pivotably coupled to a second body portion. The retainer body may also include one or more anchor engagement portions being configured to releasably couple with one or more corresponding catheter engagement portions on a hub of the catheter. The anchor device may further include first and second anchors that extend distally from the retainer body. Each anchor may include a flexible time that is deployable in a subcutaneous region to secure the retainer body relative to a penetration point. The first anchor may be coupled to the first body portion, and the second anchor may be coupled to the second body portion. The first body portion of the retainer body may be pivotable relative to the second body portion so that the first and second anchors are adjustable from one another to a removal configuration in which the flexible tines extend generally in the same direction.

Particular embodiments described herein may include a method of using a medical anchor system. The method may include advancing an anchor device toward a skin penetration point while the anchor device is in a folded condition so that a plurality of subcutaneous tines of the anchor device are generally adjacent to each other and oriented to extend in substantially the same direction. The method may also include inserting the subcutaneous tines through the skin penetration point and into a subcutaneous region adjacent to an underside of a skin layer while the anchor device is in the folded condition. Each of the subcutaneous tines may have a shape (optionally, a curved shape) which terminates at a tip of a free end during insertion through the skin penetration point. The method may further include adjusting the anchor device to a non-folded condition after the subcutaneous tines are inserted into the subcutaneous layer so that subcutaneous tines are in an anchored position in which the free ends of the subcutaneous tines extend generally away from one another. The method may include securing a medical instrument to the anchor device after the subcutaneous tines are adjusted to the anchored position in the subcutaneous region. The securing operation may include coupling one or more protrusions extending from the anchor device with one or more apertures located on the medical instrument.

These and other embodiments may provide one or more of the following advantages. First, some embodiments of an anchor system can retain a medical instrument in a desired position relative to a skin penetration point without necessarily requiring sutures or skin adhesives. Second, particular embodiments of the anchor device may be readily adaptable to use with catheters or other medical instruments of different sizes, while also securing the catheter or medical instrument to a skin penetration point in a manner that facilitates improved inspection and cleaning of the skin tissue at and around the skin penetration point. For example, some of these particular embodiments of the anchor device can provide a capless design in which the anchor device releasably couples with an external portion of the catheter or medical device without the need for an attachable cap device, thereby simplifying the process for a practitioner to inspect and clean the anchor device and the skin surface near the skin penetration point. Third, in some embodiments, the anchor device may be adjusted between a folded configuration and a non-folded configuration so that the subcutaneous anchors are arranged side-by-side and extend in generally the same direction during both installation through and removal from the skin penetration point. Fourth, in some embodiments, the anchor device can be installed in accordance with a technique that reduces or eliminates the need to shift the subcutaneous anchors tines to or from a flexed or stressed configuration. Thus, in these embodiments, the subcutaneous anchors may be readily installed and removed from the skin penetration without the need for a separate external actuator or delivery device. Fourth, in some embodiments, the configuration of the anchor device can simplify the process of installing a medical instrument onto the anchor device. Sixth, in some embodiments, the anchor device can be configured to be usable with a variety of styles and sizes of medical instruments. Seventh, in some embodiments, the anchor device can enable a hub of a catheter or other medical instrument to be positioned in close proximity to the skin penetration point.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Referring toFIG. 1, some embodiments of a medical device anchor system10include an anchor device100that releasably retains a medical instrument20in an operative position relative to a portion of skin30. The medical instrument20can be mechanically coupled to the anchor device100. The anchor device100, in turn, can be coupled to the portion of skin30. In this manner, the anchor device100can act as an intermediary member to cause the retention of the medical instrument20in a desired position with respect to the skin30. The example embodiment ofFIG. 1, can include a central venous catheter20inserted through a percutaneous opening formed in the skin (e.g., penetration point32), proceeding to the underside of the skin30, and into a vein40to provide vascular access for delivering medications, withdrawing fluids, or providing minimally invasive access into a patient.

In this example, the anchor device100can generally include a retainer body110and one or more anchors140a-bthat extend distally from a distal end of the retainer body110. As described further below, the retainer body110can be configured to couple with the medical instrument20. The one or more anchors140a-bcan be configured for deployment through a skin penetration point32and into in a subcutaneous layer34, so as to releasably retain the anchor device100with respect to the skin30. For example, the retainer body110can include the one or more anchors140aand140bthat extend distally from the retainer body111so as to penetrate through the same skin penetration point32as the medical instrument20while the retainer body111remains external to the skin penetration point. In some embodiments, the skin penetration point32may be defined by a small incision, a puncture, or the like through the dermal layers36.

The anchors140a-bcan include subcutaneous tines145a-bthat, after insertion, reside in a subcutaneous region34(e.g., a region immediately under the skin30that may comprise a fatty tissue layer) so as to secure the position of the anchor device—and the medical instrument20retained therein—relative to the penetration point32. When the tines145a-bare deployed in the subcutaneous region34, the anchor device100can be secured to the patient without the retainer body110penetrating through the dermal layers36of the patient, and without necessarily requiring sutures or adhesive tapes bonded to the skin30.

As described in more detail below in connection withFIGS. 4-6B, the anchor device100can be installed into a skin penetration point32in accordance with a technique that reduces or eliminates the need to shift the subcutaneous anchors tines145a-bof the anchors140a-bto or from a flexed or stressed configuration. As such, the anchor tines145a-bneed not undergo substantial flexing during installation or removal. In these circumstances, the subcutaneous anchors may be both installed and removed from the skin penetration point32advantageously without the need for an external actuator handle or delivery device to deploy the subcutaneous tines145a-b.

Still referring toFIG. 1, after installation of the subcutaneous anchor tines145a-binto the subcutaneous layer34, the retainer body110can receive the medical instrument20. In this example, the medical instrument20is embodied as a catheter. Hence, hereinafter the medical instrument20may alternatively be referred to as catheter20, without limiting the medical instrument20to such an embodiment. Furthermore, in some embodiments, the anchor device100can provide a capless design in which the anchor device100releasably couples with an external portion of the catheter20without the need for attaching a cap onto the retainer body110, thereby simplifying the process inspecting and cleaning the anchor device100and the skin surface near the skin penetration point32after installation.

In this embodiment, the example catheter20generally includes a proximal portion26, a hub22, and a distal portion28. The hub22can interconnect the proximal portion26with the distal portion28. In some embodiments, the proximal portion26of the catheter20may have multiple lumens that are suited to deliver multiple types of solutions to the patient. In some such embodiments, the hub22can receive the multiple lumens on the proximal end of the hub22, and merge the multiple lumens so as to connect with a single lumen distal portion28. For example, as shown inFIG. 1, the proximal portion26is depicted as having two lumens, and the distal portion28as having a single lumen that is adapted for percutaneous insertion through skin penetration point32. Hence, the hub22can serve the purpose of merging multiple proximal supply lumens into a single distal delivery lumen suited for insertion into the patient.

The hub22can further be arranged to couple the catheter20onto the anchor device100. In some embodiments, the hub22can include wings24a-b. The wings24a-bcan have features that facilitate the coupling of the hub22to the anchor device100. For example, some embodiments of the hub22can include apertures26a-bin the wings24a-b. The apertures26a-bcan be located and sized to couple with corresponding features of the anchor device100(e.g., retention posts112a-bas further described in reference toFIGS. 2A-C). In addition, the hub22can be manufactured from an elastomeric or otherwise flexible material, such as silicone or another biocompatible polymer material (e.g., PVC, polypropylene, polystyrene, or the like). In some embodiments, the hub22can be made from a combination of materials. For example, at least wings24a-bmay comprise silicone or another flexible biocompatible material so that the wings24a-band the apertures26a-bcan flexibly adjust to couple with the retention posts112a-bof the anchor device100, whereas the portions of the hub22other than the wings24a-bmay comprise a more rigid polymer material. As will be described further in reference toFIGS. 5 and 6B, such flexibility of the wings24a-bcan assist the user in coupling the hub22to the anchor device100as it relates to aligning the apertures26a-bwith the retention posts112a-b, and forcing the apertures26a-bover the mushroom-shaped heads of the retention posts112a-b. Such flexibility of the wings24a-bsimilarly assists with decoupling the hub22from the anchor device100.

Referring now toFIGS. 2A-2B, some embodiments of the anchor device100include the retainer body110and the anchors140a-b, which are connected to and extend distally from the distal end of the retainer body110. For example, the anchors140aand140bcan be connected to the retainer body110using an over-molding process to secure the anchors140a-brelative to the retainer body110. It should also be understood that there exist many manufacturing processes that can secure the anchors140aand140bto the retainer body111. In some embodiments, the retainer body111and the anchors140aand140bcan be manufactured as a single, unitary piece.

in particular embodiments, the anchor device100can be configured to be folded longitudinally about a longitudinal fold axis160(e.g., a longitudinally extending region configured for enabling the retainer body110to repeatedly adjust from a first position to a second, folded position as shown, for example, inFIGS. 3A-3B). Consequently, the retainer body110can be described as having a first retainer body portion120aand a second retainer body portion120b. In some embodiments, the first and second retainer body portions120a-bcan be substantially mirror images of each other. In alternative embodiments, the first and second portions of the anchor device100can be asymmetrical.

Preferably, at least a portion of each anchor140a-bcomprises a flexible material. In some embodiments, the anchors140a-bmay comprise a material that exhibits superelasticity. In some embodiments, at least a portion of the anchors140a-b(including the tines145a-b) may be formed from a length of nitinol wire or from a sheet of nitinol material. Alternatively, the anchors140a-bmay comprise a metal material such as stainless steel (e.g., 304 stainless, 316 stainless, custom 465 stainless, and the like), spring steel, titanium, MP35N, and other cobalt alloys, or the like. In another alternative, the anchors140a-bmay be formed from a resilient polymer material. In some embodiments, the anchors140a-bcan be formed from a material or materials that allow the tines145a-bto be flexed and can resiliently return to an unstressed position.

In the embodiment depicted inFIGS. 2A-C, each of the anchors140a-bmay be designed such that the tines145a-bhave an unstressed position wherein the tines145a-bhave a convex curvature. The convex curvature shape of the tines145a-bmay permit the tines145a-bto abut against the underside of the dermal layers36in a manner that reduces the likelihood of the tine tips146puncturing the underside of the dermal layers36. Preferably, the tine tips146are rounded bulbs or otherwise non-sharp so as to further protect the underside of the dermal layers36. In alternative embodiments, the tines145a-bmay have a generally straight shape that extends substantially perpendicular to the longitudinal shaft portions of the anchors140a-bto the rounds tips146.

Still referring toFIGS. 2A-C, the retainer body110can include first and second retainer body portions120a-barranged on opposing sides of the longitudinal fold axis160, retention posts112a-b, left and right tabs122a-b, and (optionally) a sloped nose region130. The first and second retainer body portions120a-bcan be connected to each other at an elastically flexible web portion150, which may be employed to define the fold axis160.

The retainer body110can comprise one or more biocompatible polymer materials (e.g., PVC, polypropylene, polystyrene, or the like). In some embodiments, the retainer body110can comprise a combination of such materials, for example, when the flexible web portion comprises an elastically flexible silicone material while the first and second retainer body portions120a-bcomprise a less flexible polymer material such as polypropylene, PVC, polystyrene, or the like. In some embodiments, the retainer body110can be formed using a molding process in which the retainer body110is over-molded around a portion of the anchors140a-b, especially in those embodiments in which the anchors140a-bcomprise a metallic material. For example, the first retainer body portion120acan be over-molded around a portion of anchor140aand, during the same or a different molding process, the second body portion120bcan be over-molded around a portion of anchor140b. Consequently, as described further below, when the retainer body110is folded, the respective anchors140a-b(being connected to the retainer body portions120a-brespectively) likewise move in conjunction with their respective retainer body portion120a-b.

Still referring toFIGS. 2A-C, the retention posts112a-bcan be configured to provide an effective coupling interface with a medical instrument20, while providing features that simplify the overall use of the medical device anchor system10. For example, in this embodiment, the retention posts112a-bmay provide the user with a simplified coupling technique for mating the anchor device100to the medical instrument20, and may furthermore do so without the need for an attachable cap device or skin sutures. In the depicted example, the retention posts112a-bin general are sized and spaced apart in a manner that is configured, for example, to be coupled with apertures26a-blocated on the wings24a-bof the hub22of a catheter20(refer toFIG. 1). In this embodiment, the retention posts are substantially equally spaced from the longitudinal fold axis160of the retainer body110. As described in more detail below, the retention posts112a-bcan include generally mushroom-shaped heads114a-b, stem portions116a-b, and relief portions118a-b. In such circumstances, each of the retention posts112a-bmay have generally asymmetric shape about a vertical plane extending through a central vertical axis of each respective retention post112a-band extending generally parallel to the fold axis160.

As described in more detail below, the shape and position of the retention posts112a-bcan permit a practitioner to intuitively mate the wings24a-bof the catheter20(FIG. 1) with the retainer body110with the need for secondary locking mechanisms such a cap devices that attach to the retainer body110, adhesive tapes, or the like. The mushroom-shaped heads114a-bcan have rounded tops that help the user align the apertures26a-bwith their respective retention posts112a-b. In some embodiments, the mushroom-shaped heads114a-bcan be sized to have a low interference fit with the apertures26a-b. For example, if the hub22of the medical device20can comprise an elastically flexible material, the user will be readily able to mate the hub22to the retention posts112a-bof anchor device100by forcibly and temporarily flexing the apertures26a-bover the mushroom-shaped heads114a-b. Thus, when securing the medical device20to the anchor device100, the user can align the apertures26a-bwith the mushroom-shaped heads114a-band lightly press the hub22of the medical device20against the anchor device100so that the apertures26a-bpass over and below the mushroom-shaped heads114a-b. The hub22can be pressed onto the anchor device by engaging one side at a time or by engaging both sides simultaneously. At that stage, the apertures26a-bhave passed over the mushroom-shaped heads114a-band surround the stem portions116a-bof the retention posts112a-b, thereby releasably securing the hub22of the medical instrument20in a position that is adjacent to the skin penetration point32.

When the medical instrument20is installed on the anchor device100, the apertures26a-bare engaged with the stem portions116a-bof the anchor device100. The relative diameters of the apertures26a-band the stem portions116a-bcan advantageously provide for a slightly snug fit between the apertures26a-band the stem portions116a-b. Such a snug fit can reduce the collection of contaminant materials between the apertures26a-band the stem portions116a-b.

As will be described further below in reference toFIG. 6B, the flexibility of the wings24a-bcan allow some limited angular freedom of movement between the hub22and the anchor device100, while generally restraining movement of the medical instrument20away from the skin penetration point32. Further, the limited angular freedom of movement permits the hub20of the medical instrument20to be slightly titled relative to the anchor device100, thereby permitting the hub20and the distal portion28of the medical instrument to more closely align with the skin penetration point32and reduce the stresses applied by the medical instrument20at the skin penetration point32.

Still referring toFIGS. 2A-C, the retention posts112a-bcan optionally include the aforementioned relief portions118a-b. The relief portions118a-bare generally planar or slightly curved surfaces on the sides of the retention posts112a-bthat act as material relief areas to make it easier to remove the wings24a-bfrom retention posts112a-b. In other words, the relief portions118a-bcan help the user decouple the medical instrument20from the anchor device100. Specifically, the relief portions118a-bcan allow the user to slide their finger along the side of the anchor device100, to better grasp the wings24a-bbetween their thumb and forefinger, and to thereafter “peel” the wings24a-boff the retention posts112a-b. In some circumstances, the relief portions118a-bcan similarly facilitate the act of securing the wings24a-bover the retention posts112a-b.

Still referring toFIGS. 2A-2C, the anchor device100further includes first and second tabs122a-b. The first and second tabs122a-bare configured simplify the act of manipulating and folding the anchor device100. For example, as described further in reference toFIGS. 3A-3B, the user can adjust the first and second tabs122a-bin a pivoting motion toward one another, which readily enables the user to fold the anchor device100along the longitudinal fold axis160. The first and second tabs122a-bare also configured to provide a u-shaped cutout region165between the first and second tabs122a-b. This u-shaped cutout region165can more readily provide visualization and access to the skin region under the retainer body110for inspection and cleaning of the skin30around the skin penetration point32.

The anchor device100also includes a sloped nose region130. The sloped nose region130can be a generally planar surface near the distal end of the retainer body110that is oriented at a different angle than the generally planar surfaces of the first and second retainer body portions120a-b. The sloped nose region130can decline from the generally planar surfaces of the first and second retainer body portions120a-bsuch that the nose region130slopes downward in a distal direction towards longitudinal shafts142a-bof the anchors140a-b(e.g., and thus downward to the skin penetration point32when the anchor tines145a-bare deployed). As will be described further in reference toFIG. 6B, the sloped nose region130can facilitate an orientation of the distal portion28of the medical instrument20that is directed toward the skin penetration point32. In this manner, the stresses that can potentially be exerted on the skin30proximal to the skin penetration point32by the distal portion28of the medical instrument20can be reduced.

As shown inFIG. 2C, the flexible web portion150of the anchor device100can be positioned, for example, generally centrally between the first and second retainer body portions120a-b. As previously described, the flexible web portion150can extend longitudinally from a distal face of the retainer body110to a proximal face of the retainer body110, and can be used to define the fold axis160about which the first and second retainer body portions120a-bare pivotable from the non-folded condition (FIG. 2A) to the folded condition (FIG. 3A). The left and right retainer body portions120a-bcan be connected opposing sides of the flexible web portion150. The flexible web portion150can comprise an elastically flexible biocompatible polymer material (e.g., silicon, PVC, polypropylene, polystyrene, or the like). In some embodiments, the flexible web portion150can be made of the same material as the other portions of the retainer body110. In other embodiments, the flexible web portion150can be made of a different material than the other portions of the retainer body110. In such a case, the anchor device can be made, for example, using a two-step insert molding operation. The flexible web portion150can be biased to resiliently maintain the non-folded shape of the anchor device100as depicted inFIGS. 2A-2C. When the anchor device100is folded along the fold axis160due to a user's grasp (refer, for example toFIG. 4), the flexible web portion150can undergo elastic deformation such that flexible web potion150biases the anchor device100to return the non-folded condition (FIGS. 2A and 5) upon release from the user.

Referring now toFIGS. 3A-3B, in this example embodiment, the anchor device100may include features that allow the individual anchors140a-bto be moved relative to each other so as to facilitate both insertion and removal of the anchor device100through the skin penetration point32. For example, the anchor device100may have a foldable configuration in which a first portion of the retainer body110is pivotably coupled via a flexible hinge portion to a second portion of the retainer body110.

More specifically, in this embodiment, the first retainer body portion120aand the second retainer body portion120bcan be flexibly pivoted with respect to each other along a fold axis160extending longitudinally through the retainer body110. To initiate the folding process of the anchor device100, the user can apply a bending moment about the fold axis160to the first and second tabs122a-bof the anchor device. Such a bending moment can cause an elastic deformation of the flexible web portion150so as to fold the anchor device along the fold axis160(refer toFIG. 3A). The first retainer body portion120acan be fixedly coupled to the anchor140a, and the second retainer body portion120bcan be fixedly coupled to the anchor140b. Thus, as shown inFIGS. 3A, when the first and second retainer body portions120a-bare pivoted about the fold axis160, the two anchors140a-blikewise pivot relative to one another. This process of pivoting can cause the anchor device to transition from a non-folded condition (shown inFIGS. 2A-2Cand inFIG. 1) in which the tines145a-bextend generally away from one another to a folded condition (shown inFIGS. 3A-3B), in which the tines145a-bare generally adjacent to each other and oriented to extend in substantially the same direction. Similarly, when the bending moment from the user is released, the anchor device can be biased to return the anchor device100from the folded condition to the non-folded condition. In the depicted embodiment, the tines145a-bcan be rotated about 75-degrees to about 105-degrees, and preferably about 90-degrees, during the transition between the non-folded condition and the folded condition. As described in more detail below, the anchor device100can be arranged in the folded condition during both insertion and removal of the subcutaneous tines145a-bso as to reduce the likelihood of the tines145a-bcausing damage to the skin30.

Referring now toFIGS. 4-5, in some embodiments, the medical instrument20can include a catheter to be inserted through the penetration point32of the skin30as part of a medical procedure. For example, in the embodiment depicted inFIG. 1, a central venous catheter20can be inserted into a percutaneous opening surgically formed in the skin (e.g., penetration point32), to the underside of the skin30, and into a vein40to provide vascular access for delivering medications or minimally invasive devices into a patient.

After placement of the catheter20through the penetration point32of the skin30, the user can grasp the anchor device100in the folded condition and approach the penetration point32such that the free ends of the tines145a-bare contemporaneously inserted through the penetration point32while the tines145a-bare in a generally side-by-side condition (as depicted inFIG. 4). In particular embodiments, the subcutaneous tines145a-bare inserted through the skin penetration point32while the user conveniently grasps the tabs122a-bof the retainer body110of the anchor device100and applies an insertion force until the convexly curved body portions of the subcutaneous tines145a-bare positioned below the surface of the skin30(while the remainder of the anchor device100resides external to the skin30).

As the anchor device100is inserted through the penetration point32, the tines145a-bare maintained in a generally non-stressed configuration (e.g., a first shape or a steady-state shape) while passing through the penetration point32in a manner that reduces the likelihood of trauma to the surrounding skin tissue30. As the tines145a-bare collectively advanced through the penetration point32, the free ends of the tines145a-bare moved beneath the dermal skin layers36of the skin30.

When the tines145a-breach the subcutaneous region34, the retainer body110can adjusted to the unfolded condition so that the tines145a-bare shifted relative to one another, resulting in the tines145a-bextending outwardly away from one another (as depicted inFIG. 5). During that process of unfolding the retainer body110, each tine145a-bmay retain their generally non-stressed configuration (e.g., the first shape or the steady-state shape). Thus, the anchor device100can be installed in accordance with a technique that reduces or eliminates the need to shift the subcutaneous anchors tines145a-bto or from a flexed or stressed configuration during the passage through the skin penetration point32. As such, the subcutaneous anchors tines145a-bneed not undergo substantial flexing during installation or removal, and in some embodiments, the subcutaneous anchors tines145a-bcan comprise a generally less costly material (such as stainless steel or biocompatible polymers) rather than more costly materials required for superelastic flexing.

As previously described, the retainer body110can secure the medical instrument20relative to a skin penetration point32. With the anchor device100positioned such that subcutaneous anchors tines145a-bare in their deployed configuration, as shown inFIG. 5, the previously inserted medical instrument20can be releasably secured to the anchor device100. As shown inFIG. 5, the directional arrow200depicts an example motion of manually positioning the medical instrument20adjacent to the anchor device100to prepare for the installation of the medical instrument20onto the anchor device100.

Referring now toFIGS. 6A-B, the medical device anchor system10ofFIGS. 4-5is releasably engaged with the medical instrument20. In this embodiment, the hub22of the medical instrument20(e.g., a catheter) may be removably attached to the retainer body110using one or more apertures26a-bon the wings24a-bof the hub22that mechanically engage with corresponding retention posts112a-bon the retainer body110. To simplify the process of engaging the apertures26a-bwith the retention posts112a-b, the hub22may comprise an elastically flexible material, such as silicone or another biocompatible polymer material. Such flexibility can assist the user to install the medical instrument20onto the anchor device100by making it possible to bend, stretch, and generally make it easy to maneuver the wings24a-bof the hub22that comprise the apertures26a-b. In some embodiments, at least a flexible wall portion comprising the wings24a-bmay comprise silicone or another biocompatible polymer material so that left wing24acan flexibly adjust relative to a right wing24b, or at least to the barrel of the hub22. In some embodiments, the hub22can comprise a composite material. That is, the wings24a-bmay comprise silicone or another flexible polymer material, while the other portions of the hub22may comprise a more rigid material such as a polycarbonate, PVC, or the like. In such circumstances, the apertures26a-bcan be aligned with and forced over the corresponding retention posts112a-b, and thereafter (if desired), one aperture26aor26bcan be lifted from the retainer body110while the second aperture26bor26aremains secured to the retainer body110. With the apertures26a-bcoupled with the retention posts112a-b, the medical instrument20is installed on the anchor device100.

As shown inFIG. 6B, the anchor device100releasably retains the medical instrument20(e.g., catheter) in an operative position relative to a portion of skin30(e.g., the skin penetration point32). The medical instrument20is mechanically coupled to the anchor device100, as described above. The anchor device100, in turn, is coupled to the portion of skin30, as described above. In such embodiments, the anchor device100can be secured to the patient without necessarily requiring sutures or adhesive tapes bonded to the skin30. A distal portion28of the catheter20penetrates a skin penetration point32and distally extends into the subcutaneous layer34. In this view, it can be seen that some embodiments of the system10can enable the distal end of the hub22to be positioned closely to the skin penetration point32. Such a configuration provides a compact anchor system10that is convenient to install and maintain. This configuration can minimize the lengths of the tubing proximal to the patient, and reduce the need for securement of such tubing or other portions of the medical instrument20to the patient using tapes, adhesive dressings, and the like.

It can also be seen inFIG. 6Bthat the hub22of the catheter20may optionally inclined at an angle in relation to the skin surface30. Such an orientation between the hub22and the skin30may, in some circumstances, reduce the stresses applied to the skin penetration point32of the patient by the distal portion28of the catheter20. In particular, the example orientation depicted inFIG. 6Benables the distal portion28to be inclined at an angle in relation to the skin surface30which can thereby reduce the need for the distal portion28of the catheter20to have the a significant bend at the skin penetration point.

Still referring toFIG. 6B, in some embodiments, the apertures26a-bof the hub22can have a slidable fit in relation to the stems116a-bof the retention posts112a-b. The slidable fit relationship can provide the hub22with a freedom of movement whereby the distal portion28will tend to position itself in relation to the skin30so as to naturally minimize the amount of force applied by the distal portion28to the skin30, and the sloped nose portion130of anchor device100can further allow the distal portion28to do so. For example, as described above in reference toFIGS. 2A-2C, the sloped nose region130can be a planar surface near the distal end of the retainer body110that is oriented at a different angle than the generally planar surfaces of the first and second portions120a-bof the retainer body110. The sloped nose region130can be declined relative to the generally planar upper surfaces of the first and second portions120a-bsuch that the sloped nose region130slopes downward in a distal direction towards the skin penetration point32. Such a configuration of the anchor device100can allow the hub22of the catheter20to be further tilted at greater angle relative to the skin30and to the anchor device100. The sloped nose region130can provide a material relief area that removes hindrances to the hub22from being positioned at an incline with relation to the skin. The sloped nose region130can also provide a planar surface to support the hub22in the inclined position in relation to the skin30. Further, in some embodiments, the retention posts112a-bcan have their axes oriented at an angle generally perpendicular to the sloped nose region130(and thus non-perpendicular to the generally planar upper surfaces of the first and second portions120a-b). In such a configuration, the retention posts112a-bcan encourage the hub22to be inclined in relation to the skin30because of the physical interface between the retention posts112a-band the apertures26a-bof the hub22.

In some embodiments, some components of the system10can be provided in a sterilized kit that pairs a particular type of catheter20or other medical instrument with a corresponding anchor device100. The particular type of catheter20or other medical instruments in the kit is compatible for releasably mating with the retainer body110of the anchor device100in the kit. Each kit can include one or more anchor devices100and the particular type of catheter20or other medical instrument enclosed within a flexible packaging material, which preferably includes indicators that identify the type of catheter20or other medical instruments that is provided along with instructions for deploying and removing the anchor device100. The kit may include a one-to-one ratio for the quantity of anchor devices100to the quantity of catheters20. In other embodiments, the kit may include multiple anchor devices100(e.g., having differently sized or shaped tines145a-b) for each catheter20contained therein.

Alternatively, in some embodiments, the anchor device100can be provided in individual, sterilized packets so that a practitioner can readily open such a packet and access the selected anchor device prior to insertion into the skin penetration point. Such individual packets can include a single anchor device enclosed within a flexible packaging material, which preferably includes indicators that identify the types of catheters or other medical instruments that are compatible for releasably mating with the retainer body110. As such, a practitioner can readily select one of the packets for use after the type of catheter or medical instrument is selected for a particular patient.

Referring now toFIGS. 7A-Cand8, some embodiments of the device100Can be configured to oprate in combination with an optional adapter tool300, which Permits the anchor device100to engage with a catheter420or other medical instrument Even if no wings (or wings of a non-corresponding size) are provided. In such embodiments, the adapter tool300may be configured to engage and grip an exterior of the catheter420or other medical instrument while also providing supplemental wings324a-bfor mating with the retainer body110of the anchor device100.

ReferringFIGS. 7A-C, the adapter tool300can include a first portion (hub322) configured to releasably couple to a catheter or other medical instrument and a second portion (wings324a-b) configured to releasably engage the retainer body110of the anchor device. In this embodiment, the first portion of the adapter tool300comprises a hub322that defines a lumen340with a longitudinal slit330through one wall of the hub322. The longitudinal slit330can be flexibly opened to receive a medical instrument to be positioned within the lumen340. In an example embodiment, the medical instrument can be a shaft328that is substantially surrounded by (and, in this embodiment, full surrounded by) the lumen340of the hub322of the adapter tool300. To illustrate,FIG. 7Ashows the adapter tool300without a medical instrument;FIG. 7Bdepicts the installation process of placing a medical instrument (e.g., a shaft328of a catheter or other medical instrument) into the lumen340of the adapter tool300by elastically deforming the hub322to widen the longitudinal slit330; andFIG. 7Cillustrates the shaft328installed in the adapter tool300such that the hub322fully surrounds and grips the exterior the shaft328. In this configuration (as shown inFIG. 7C), the adapter tool300is prepared to be installed onto an anchor device100.

The adapter tool300can comprise an elastically flexible biocompatible polymer material such as silicon, PVC, polypropylene, polystyrene, or the like. In some embodiments, the adapter tool300can comprise a composite structure. For example, the adapter tool300can have various layers of disparate materials. In some embodiments the adapter tool300can have a soft durometer material (e.g., an elastomeric material such as silicon) on the surface layer of the lumen340that contacts the medical instrument, and a stiffer polymer shell (e.g., polypropylene or PVC) on the upper layer (at least along the outer area of the hub322). The softer inner layer can be bonded to a lower surface of the more rigid upper layer. Such a composite construction of the adapter tool300can provide sufficient frictional characteristics from the inner layer to grip the medical instrument inside of the lumen340while the upper layer of more rigid material provide additional rigidity and maintains the compression of the inner layer upon the medical instrument. Further, in some embodiments the wings324a-bcan comprise the same material as the other portions of the adapter tool300. In other embodiments, the wings324a-bcan comprise a different material than the other portions of the adapter tool300, such that the wings324a-bhave more flexibility so as to make the installation of the adapter tool300to the anchor device more convenient.

Still referring toFIGS. 7A-C, in this embodiment, the second portion of the adapter tool300comprises wings324a-bthat extend laterally outward from opposing sides of the hub322. The wings324a-bof the adapter tool300can include apertures326a-b. The apertures326a-bcan be configured to couple with retention posts of an anchor device, such as retention posts112a-bof anchor device100as described above.

The adapter tool300can have a variety of styles of lumens340so as to adapt to various types of medical devices. For example, while the example embodiment of the adapter tool300shown has a lumen340with a circular cross-section, other configurations are envisioned, e.g., square, oval, or triangular cross-sections, and the like. In addition, various sizes of the lumen340are envisioned. For example, the lumen340can be sized to couple with tubes having various outer-diameter dimensions e.g., ¼″, 3/16″, ⅛″, 3/32″, 1/16″, as well as other sizes including metric sizes.

In some embodiments, a plurality of the adapter tools300can be provided in a sterilized kit that provides adapters300having different shapes hubs322that are configured to mate with different types of catheter20or other medical instruments. Preferably, the plurality of the adapter tools300packaged together in the kit can include similar wing portions324a-bsuch that any one of the plurality of the adapter tools300in the kit can be selected for mating with a predetermined retainer body110of the anchor device100. Each kit can include plurality of the adapter tools300and, optionally, at least one of the particular types of anchor devices100enclosed within a flexible packaging material, which preferably includes indicators that identify the type of catheter20or other medical instruments that are compatible with the plurality of the adapter tools300. The kit may include multiple adapters300(e.g., having differently sized or shaped hub portions322) for each anchor device100contained therein. As such, a kit including multiple adapter tool300parts, with a range of different lumen sizes and/or shapes are envisioned. In another embodiment of a kit, a variety of the adapter tool300parts having different lumen sizes and/or shapes can be included with one or more anchor devices100designed to couple with the variety of adapter tool300parts. Such a kit can provide practitioners with a flexible system having the equipment to handle a variety of sizes and styles of medical instruments that can be anchored to a patient. In some embodiments, the kit, or individual parts comprising the kit, may be provided in sterile packaging.

Referring now toFIG. 8, some embodiments of an example medical device anchor system400include an anchor device100coupled to an adapter tool300that releasably retains a medical instrument420in an operative position relative to a portion of skin30(e.g., skin penetration point32). The medical instrument420can be mechanically coupled to the anchor device100by using the adapter tool300, especially in circumstances when the medical instrument420is not equipped with corresponding wings (such as the wings24a-bshown inFIG. 1). The anchor device100, in turn, can be releasably anchored to the skin penetration point32as described, for example, in connection withFIGS. 4-5herein. In this manner, the anchor device100and the adapter tool300can act as an intermediary members to bring about the retention of the medical instrument420in a desired position with respect to the skin penetration point32.

In this embodiment, the distal portion (shaft328) of the medical instrument420can be percutaneously delivered in the patient via the skin penetration point32. The tines145a-bof anchors140a-bof anchor device100can be inserted through the skin penetration point32with the anchor device100in a folded configuration as described above in connection withFIG. 4. After insertion of the anchor tines145a-b, the anchor device100can be adjusted to a non-folded configuration wherein the tines145a-b of anchors140a-bare extending outwardly away from one another under the dermal layers36of the patient, as described in connection withFIG. 5. The adapter tool300can be selected according to the type of the medical instrument420(e.g., based upon the diameter of the shaft328in this embodiments) and thereafter releasably installed on the distal portion (shaft328) of the medical instrument420, as described in connection withFIGS. 7A-C. The adapter tool300can be releasably secured onto the anchor device100, for example, by pressing the wings324a-bso that the apertures326a-bare forced onto retention posts112a-b, as in the manner described above. It should be understood that the adapter tool300can be oriented in relation to the anchor device100such that longitudinal slit330through one wall of the hub322faces downwardly toward the anchor device100and is adjacent to the anchor device100, so that the medical instrument420can be securely retained in the adapter tool300.

Referring now toFIG. 9, some alternative embodiments include an anchor device500in which the position of the retention posts can be adjusted relative to the retainer body. For example, the adjustable retention posts512a-bcan be selectively mounted at different positions relative to the retainer body110, which can provide the capability for the user to select different dimensional distances between the retention posts. This feature can enable the anchor device to mate with any of a wider variety of medical instruments. That is, in some embodiments, the positions of the retention posts on the retainer body can be adjustable to accommodate coupling with a variety of medical instruments that have different sized mounting features (e.g., such as different catheters having differently shaped hubs/wings). For example, certain catheter hubs may have mounting features that have a different dimensional spacing in comparison to other catheter hubs. Having an anchor device with retention posts that can be adjusted to different dimensional spacing can enable the anchor device to mate with any of a variety of catheter hubs. This feature can also simplify the user's selection of anchor devices. In other words, since one anchor device can be adapted to a wider range of medical instruments, a single anchor device can be selected and configured in accordance with the mounting features of the medical instrument immediately before deployment.

The retainer body110of the example anchor device500depicted inFIG. 9is substantially similar to the embodiments described above, but with the addition of multiple landings513a-balong the upper face of the retainer body110, so as to receive the adjustable retention posts512a-b. Each landing513a-bcan include a mating structure to engage with a corresponding mating structure on the adjustable retention posts512a-brespectively. For example, in some embodiments the landings513a-bcan have a mating cavity that lockingly receives corresponding projections519a-bon the underside of the retention posts512a-b(e.g., a snap-fit engagement). In other embodiments, the landings513a-bcan include threaded holes, and the corresponding projections519a-bon the underside of the retention posts512a-bcan include male threads so that the retention posts512a-bcan be screwed onto the landings513a-b.

Still referring toFIG. 9, in this embodiment, the landings513aand513bare configured in pairs. That is, each of the landings513aon the first side has a corresponding landing513bon the second side, and each of the landings513bon the second side has a corresponding landing513aon the first side. For example, the distal-most landing513aon the left side of the anchor device500, corresponds to the distal-most landing513bon the right side of the anchor device500. When, for example, the distal-most landing513aon the left side is used to mount the adjustable retention post512a, then the distal-most landing513bon the right side can be used to mount the adjustable retention post512b. This pattern holds true for the other less distally located landings513a-bas well.

Each pair of landings513a-bcan be spaced apart from each other at a different distance in comparison to the other pairs of landings513a-b. For instance, as depicted in the example embodiment shown inFIG. 9, the distal-most landings513a-bcan be a pair of landings513a-bthat are spaced the closest together (in comparison to the other pairs of landings513a-b). In contrast, the pair of landings513a-blocated most proximally on the anchor device500can be a pair of landings513a-bthat are spaced the farthest apart (in comparison to the other pairs of landings513a-b). The pairs between the distal-most and the most proximal can separated by distances that are between the closest and the farthest spacing distances. By selecting a suitable pair of landings513a-b, and mounting the adjustable retention posts512a-bto the suitable landings513a-b, the anchor device500can be adjusted to accommodate a variety of medical instruments that have various sizes of mating structures. After the adjustable retention posts512a-bare mated with the selected landings513a-b, the anchor device500can operate in a manner substantially similar to the configuration described in connection withFIGS. 4-6B.

Referring now toFIG. 10, some alternative embodiments of an anchor device600can be equipped with retention members that are flexible and therefore movable with respect to the retainer body. The flexible retention members612a-bmay have a different shape and configuration from the previously described retention posts112a-b(FIGS. 2A-C). Such flexibility of the retention members612a-bcan enable the anchor device600to couple with any of a variety of medical instruments having a different of mounting interfaces. For example, while some medical instruments include wings with apertures, other medical instruments may be configured with a different type of mounting interface. Providing an anchor device600with flexible retention members612a-bcan enable the anchor device600to thereby couple with a wider variety of medical instruments. This feature can permit simplified user selection of anchor devices by providing a single anchor device600that is adaptable to a wider variety of medical instruments.

As shown inFIG. 10, in some embodiments, the flexible retention members612a-bcan comprise flexible binding straps, for example, having a structure somewhat similar to cable ties. The flexible retention members612a-bcan be fixedly attached to the upper face of the retainer body, for example by insert molding, welding, gluing, clamping, and so on. The elongate flexible portions of the flexible retention members612a-bcan be used to capture and secure the medical instrument20. For example, as shown, in some embodiments the flexible retention members612a-bcan be routed through apertures located in the wings of a catheter hub. In other embodiments, the flexible retention members612a-bcan be routed so as to capture the medical instrument in many other manners—such as by routing the flexible retention members612a-bover flanges or other outer surfaces, across outer surfaces in an “x” pattern, over individual tubes of a multi-tube device, and so on.

When the flexible retention members612a-bare engaged with the medical instrument (e.g., routed through apertures located in the wings of a catheter hub in the depicted embodiment), the flexible retention members612a-bcan be firmly locked in place using a receiver locking device613a-b. In some embodiments, the receiver locking device613a-bcan be a ratchet-type receiver mechanism that locks with a tooth surface along the side of the corresponding flexible retention member612a-b. Such a configuration can allow the flexible retention members612a-bto be pulled through the ratchet-type receiver mechanism613a-bin one direction, which thereby locks the flexible retention members612a-btightly in place until the medical instrument20is released at the end of the procedure by unlocking or severing the retention members612a-b. As shown in the example embodiment anchor device600, the ratchet-type receiver mechanisms613a-bcan be fixedly mounted to the retainer body. To lock the medical instrument20in place on the anchor device600, the free-ends of the flexible retention members612a-bcan be routed through the ratchet-type receiver mechanisms613a-band pulled tight. In this fashion a medical instrument can be coupled to an anchor device600using flexible retention members612a-b.

In another embodiment, one flexible retention member (e.g., member612b) can have a free-end with a pointed tip, while the other flexible retention member (e.g.,612a) can have a free-end with an integral ratchet-type receiver mechanism. Then, after interfacing the flexible retention members with the medical instrument, the two flexible retention members612a-bcan be joined together by routing the pointed tip through the ratchet-type receiver mechanism. The medical instrument can be secured to the anchor device by removing the slack from the flexible retention members. In this fashion a medical instrument can be coupled to an anchor device600using flexible retention members.

A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the scope of the invention. Accordingly, other embodiments are within the scope of the following claims.