Catheter placement device including mechanical gain mechanism

Abstract

An insertion tool for inserting a catheter into a patient's body is disclosed. The insertion tool integrates needle insertion, guidewire advancement, and catheter insertion into a single device. The insertion tool comprises a housing in which at least a portion of the catheter is initially positioned; a hollow needle extending distally from the housing with at least a portion of the catheter pre-positioned on the hollow needle; and a guidewire pre-positioned within the hollow needle. A guidewire advancement assembly is also included for selectively advancing the guidewire distally beyond the distal end of the hollow needle in preparation for distal advancement of the catheter. A catheter advancement assembly is also included for selectively advancing the catheter into the patient's body. The catheter advancement assembly includes a mechanical gain mechanism coupled between the slide of the insertion tool and the catheter.

Description

Technical Field

[0001] The present invention relates to a catheter placement device including a mechanical gain mechanism.

Summary of the Invention

[0002] Disclosed herein is a catheter insertion device assembly which, according to some embodiments, includes a catheter having a catheter tube defining a catheter lumen extending between a catheter distal end and a catheter hub at the catheter proximal end, the catheter hub being disposed within a housing. The assembly further includes a needle configured to be inserted into a patient between a skin surface and a blood vessel, the needle defining a needle lumen extending between a needle distal end and a needle proximal end coupled to the housing, the needle being pre-positioned within the catheter lumen such that the needle distal end extends beyond the catheter distal end and the needle proximal end extends proximally beyond the catheter hub. The assembly further includes a guidewire extending between a guidewire distal end and a guidewire proximal portion, the guidewire being pre-positioned within the needle lumen such that the guidewire distal end is positioned proximal to the needle distal end and the guidewire proximal portion extends proximally beyond the needle proximal end. The assembly further includes a slide displaceable along an exterior of the housing, the slide being coupled to the guidewire proximal portion such that displacement of the slide causes displacement of the guidewire. The assembly further includes a mechanical gain mechanism coupled between the slide and the catheter hub such that the slide provides an input force to the mechanical gain mechanism and the mechanical gain mechanism provides an output force to the catheter hub in response to the input force, the output force being greater than the input force.

[0003] In some embodiments, the input force and the output force are each directed distally, and in some embodiments, the output force is twice as large as the input force. In some embodiments, the displacement of the slide causes simultaneous displacement of the catheter and the guidewire, and in some embodiments, the displacement of the catheter is smaller than the simultaneous displacement of the guidewire.

[0004] In some embodiments, the mechanical gain mechanism includes a lever, and in some embodiments, the lever includes an opening through which a needle passes. In some embodiments, the lever includes (i) a first end coupled to the slide, (ii) a second end that defines a pivot point together with the bottom housing portion, and (iii) an intermediate point coupled to the catheter hub. In such embodiments, distal displacement of the slide relative to the bottom housing portion causes distal displacement of the catheter relative to the bottom housing portion.

[0005] In some embodiments, the lever includes (i) a first end coupled to the slide, (ii) a second end defining a pivot point together with the needle hub, and (iii) an intermediate point coupled to the catheter hub. In such embodiments, distal displacement of the slide relative to the bottom housing portion causes distal displacement of the catheter relative to the needle.

[0006] In some embodiments, the lever includes (i) a first end coupled to the slide, (ii) a second end coupled to the needle hub, and (iii) an intermediate point that defines a pivot point together with the catheter hub. In such embodiments, distal displacement of the slide relative to the bottom housing portion causes distal displacement of the catheter relative to the needle.

[0007] In some embodiments, the lever includes (i) a first end slidably coupled to the cam surface of the slide, (ii) a second end coupled to the catheter hub, and (iii) an intermediate point adjacent to the bend of the lever that defines a pivot point together with the needle hub. In such embodiments, distal displacement of the slide relative to the bottom housing portion causes lateral displacement of the first end, which in turn causes distal displacement of the catheter relative to the needle.

[0008] In some embodiments, the mechanical gain mechanism includes a tension member having (i) a first end coupled to a slide, (ii) a second end coupled to a bottom housing portion, and (iii) a loop portion coupled to a catheter hub. In such embodiments, distal displacement of the slide relative to the bottom housing portion causes the loop portion to displace the catheter distally relative to the bottom housing portion.

[0009] In some embodiments, the mechanical gain mechanism includes (i) a first gear rack coupled to the slide, (ii) a second gear rack coupled to the bottom housing portion, and (iii) a pinion gear coupled to the catheter hub, the pinion gear meshing with the first and second gear racks. In such embodiments, distal displacement of the slide relative to the bottom housing portion causes the pinion gear to rotate and distally displace along the bottom housing portion, resulting in the catheter co-displacing distally with the pinion gear relative to the bottom housing portion.

[0010] In some embodiments, the assembly further includes a safety assembly configured to cover the distal tip of the needle when the needle is withdrawn from the catheter, and the safety assembly is coupled between the catheter hub and a mechanical gain mechanism. In such embodiments, distal displacement of the slide causes distal displacement of the safety assembly, which in turn causes distal displacement of the catheter.

[0011] In some embodiments, the slide is configured to be displaced by a first distance and a subsequent second distance, wherein the first distance displacement of the slide displaces the guidewire distally to the needle by a first guidewire distance, and the subsequent second distance displacement of the slide displaces (i) the guidewire distally to the needle by a second guidewire distance, and (ii) the catheter by a first catheter distance, where the first catheter distance is shorter than the second guidewire distance.

[0012] Furthermore, this specification discloses a method for implanting a catheter in a blood vessel, the method comprising, according to some embodiments, inserting the needle of a catheter insertion device assembly through the patient's skin such that the distal end of the needle is positioned in the blood vessel, (i) the needle is pre-positioned in the lumen of the catheter of the catheter insertion device assembly, and (ii) the guidewire of the catheter insertion device assembly is pre-positioned in the lumen of the needle. The method further comprises advancing the guidewire distally along the lumen of the needle such that the guidewire extends beyond the distal end of the needle, and advancing the catheter distally along the needle by a catheter distance such that the distal end of the catheter is displaced from a position proximal to the distal end of the needle to a position distal to the distal end of the needle, wherein advancing the catheter distally includes displacing the slide of the catheter insertion device assembly distally with respect to the housing of the catheter insertion device assembly by a slide distance, the slide distance being longer than the catheter distance.

[0013] In some embodiments of this method, displacing the slide distally includes applying a first force distal to the slide, and advancing the catheter distally includes applying a second force distal to the catheter, the second force being greater than the first force.

[0014] In some embodiments of this method, displacing the slide distally involves rotating a lever about a pivot point, which is connected to the catheter hub, needle hub, or housing.

[0015] In some embodiments of this method, the catheter insertion device includes a tension member having (i) a first end coupled to a slide, (ii) a second end coupled to a housing, and (iii) a loop portion coupled to a catheter. In such embodiments, distal displacement of the slide relative to the housing causes the loop portion to displace the catheter distally along the needle.

[0016] In some embodiments of this method, the catheter insertion device includes (i) a first gear rack coupled to a slide, (ii) a second gear rack coupled to a housing, and (iii) a pinion gear coupled to a catheter, the pinion gear meshing with the first and second gear racks. In such embodiments, distal displacement of the slide relative to the housing causes the pinion gear to rotate and distally displace along the housing, thereby distally displacing the catheter along the needle.

[0017] These and other features of embodiments of the present invention may be more fully apparent from the following description and the appended claims, or may be understood by the implementation of embodiments of the present invention described below.

[0018] A more detailed description of this disclosure is provided with reference to specific embodiments shown in the accompanying drawings. It is understood that these drawings represent only typical embodiments of the invention and are therefore not intended to limit its scope. Exemplary embodiments of the invention are described and illustrated with additional features and details using the following accompanying drawings. [Brief explanation of the drawing]

[0019] [Figure 1A] These are various diagrams of a catheter insertion device according to one embodiment. [Figure 1B] These are various diagrams of a catheter insertion device according to one embodiment. [Figure 2A] Figures 1A and 1B show various exploded views of catheter insertion devices. [Figure 2B] Figures 1A and 1B show various exploded views of catheter insertion devices. [Figure 3A] Figures 1A and 1B illustrate various steps in the use of the catheter insertion device according to one embodiment. [Figure 3B]Various diagrams showing one stage of the use of the catheter insertion device of FIGS. 1A and 1B, according to one embodiment. [Figure 4A] Various diagrams showing one stage of the use of the catheter insertion device of FIGS. 1A and 1B, according to one embodiment. [Figure 4B] Various diagrams showing one stage of the use of the catheter insertion device of FIGS. 1A and 1B, according to one embodiment. [Figure 5A] Various diagrams showing one stage of the use of the catheter insertion device of FIGS. 1A and 1B, according to one embodiment. [Figure 5B] Various diagrams showing one stage of the use of the catheter insertion device of FIGS. 1A and 1B, according to one embodiment. [Figure 6A] Various diagrams showing one stage of the use of the catheter insertion device of FIGS. 1A and 1B, according to one embodiment. [Figure 6B] Various diagrams showing one stage of the use of the catheter insertion device of FIGS. 1A and 1B, according to one embodiment. [Figure 7A] Various diagrams showing one stage of the use of the catheter insertion device of FIGS. 1A and 1B, according to one embodiment. [Figure 7B] Various diagrams showing one stage of the use of the catheter insertion device of FIGS. 1A and 1B, according to one embodiment. [Figure 8] One embodiment shows one stage of the use of the catheter insertion device of FIGS. 1A and 1B. [Figure 9] One embodiment shows one stage of the use of the catheter insertion device of FIGS. 1A and 1B. [Figure 10A] Various diagrams showing needle safety components and environments for a catheter insertion device, according to one embodiment. [Figure 10B] Various diagrams showing needle safety components and environments for a catheter insertion device, according to one embodiment. [Figure 10C] Various diagrams showing needle safety components and environments for a catheter insertion device, according to one embodiment. [Figure 11A]These are various diagrams of a catheter insertion device according to one embodiment. [Figure 11B] These are various diagrams of a catheter insertion device according to one embodiment. [Figure 11C] These are various diagrams of a catheter insertion device according to one embodiment. [Figure 11D] These are various diagrams of a catheter insertion device according to one embodiment. [Figure 12A] Figures 11A to 11D show various diagrams of parts of a catheter insertion device. [Figure 12B] Figures 11A to 11D show various diagrams of parts of a catheter insertion device. [Figure 13A] Figures 11A to 11D show various diagrams of parts of a catheter insertion device. [Figure 13B] Figures 11A to 11D show various diagrams of parts of a catheter insertion device. [Figure 14A] Figures 11A to 11D illustrate various stages of using the catheter insertion device according to one embodiment. [Figure 14B] Figures 11A to 11D illustrate various stages of using the catheter insertion device according to one embodiment. [Figure 14C] Figures 11A to 11D illustrate various stages of using the catheter insertion device according to one embodiment. [Figure 14D] Figures 11A to 11D illustrate various stages of using the catheter insertion device according to one embodiment. [Figure 14E] Figures 11A to 11D illustrate various stages of using the catheter insertion device according to one embodiment. [Figure 14F] Figures 11A to 11D illustrate various stages of using the catheter insertion device according to one embodiment. [Figure 15] This is an exploded view of a catheter insertion device according to one embodiment. [Figure 16] This is a perspective view of a portion of a guide wire lever according to one embodiment. [Figure 17A]Figure 15 is a cross-sectional view of the proximal portion of the catheter insertion device. [Figure 17B] Figure 15 is a cross-sectional view of the proximal portion of the catheter insertion device. [Figure 18] Figure 15 is a perspective view of the proximal portion of the upper housing of the catheter insertion device. [Figure 19] Figure 15 is a cross-sectional view of the proximal portion of the catheter insertion device. [Figure 20A] These are various diagrams of a needle safety component according to one embodiment. [Figure 20B] These are various diagrams of a needle safety component according to one embodiment. [Figure 21A] Figures 20A and 20B show various diagrams of the needle safety components and their associated carriages. [Figure 21B] Figures 20A and 20B show various diagrams of the needle safety components and their associated carriages. [Figure 21C] Figures 20A and 20B show various diagrams of the needle safety components and their associated carriages. [Figure 21D] Figures 20A and 20B show various diagrams of the needle safety components and their associated carriages. [Figure 22A] This is a cross-sectional view of the proximal portion of the catheter insertion device shown in Figure 15, according to one embodiment. [Figure 22B] This is a cross-sectional view of the proximal portion of the catheter insertion device shown in Figure 15, according to one embodiment. [Figure 23A] Figure 15 is a side cross-sectional view of a portion of the device, illustrating various embodiments of a mechanical gain mechanism having a lever, according to several embodiments. [Figure 23B] Figure 15 is a side cross-sectional view of a portion of the device, illustrating various embodiments of a mechanical gain mechanism having a lever, according to several embodiments. [Figure 23C] Figure 15 is a side cross-sectional view of a portion of the device, illustrating various embodiments of a mechanical gain mechanism having a lever, according to several embodiments. [Figure 23D]Figure 15 is a side cross-sectional view of a portion of the device, illustrating various embodiments of a mechanical gain mechanism having a lever, according to several embodiments. [Figure 23E] Figure 15 is a side cross-sectional view of a portion of the device, showing another embodiment of a mechanical gain mechanism having a tensile member according to several embodiments. [Figure 23F] Figure 15 is a side cross-sectional view of a portion of the device, showing another embodiment of a mechanical gain mechanism having a pinion gear positioned between opposing gear racks, according to several embodiments. [Figure 24] This is a block diagram of a method for inserting a catheter into a blood vessel, according to several embodiments. [Modes for carrying out the invention]

[0020] Here, we refer to figures in which similar structures are denoted by the same reference numerals. It should be understood that the drawings are illustrative and schematic representations of exemplary embodiments of the present invention and are not limiting, nor are they necessarily drawn to dimensions.

[0021] For clarity, the term “proximal” refers to a direction relatively close to the clinician using the device described herein, while the term “distal” refers to a direction relatively far from the clinician. For example, the end of the catheter located inside the patient’s body is considered the distal end of the catheter, and the end of the catheter remaining outside the body is the proximal end of the catheter. Also, the terms “include,” “having,” and “possessing,” as used herein, including in the claims, have the same meaning as the term “equipped with.”

[0022] The phrases “connected to,” “coupled to,” and “in communication with” refer to any form of interaction between two or more entities, including but not limited to mechanical, electrical, magnetic, electromagnetic, fluid, and thermal interactions. Two components can be coupled to one another even if they are not in direct contact with each other. For example, two components can be coupled to one another through an intermediate component.

[0023] Any method disclosed herein includes one or more steps or actions for carrying out the described method. The steps and / or actions of the method may be interchangeable with one another. In other words, the order and / or use of any particular steps and / or actions may be modified unless a particular order of steps or actions is required for the proper operation of the embodiment. Furthermore, only a subroutine or portion of a method described herein may constitute a separate method within the scope of this disclosure. In other words, some methods may include only a portion of the steps described in a more detailed method. In addition, all embodiments disclosed herein are combinatorial and / or interchangeable unless otherwise stated, or unless such combination or substitution is contrary to the described operability of any embodiment.

[0024] Embodiments of the present invention generally relate to tools for assisting the placement of catheters or other tubular medical devices in patients. For example, catheters of various lengths are typically placed in a patient's body to establish access to the patient's vascular system and enable the infusion of medications or the aspiration of bodily fluids. The catheter insertion tools described herein facilitate the placement of such catheters. While the following description focuses on the placement of specific types and relatively short length catheters, it should be noted that a wide variety of catheters of different types, sizes, and lengths can be inserted through these devices, including mid- or long-term indwelling peripheral venous catheters, PICCs, central venous catheters, and the like. In one embodiment, catheters having lengths between approximately 6.4 cm (2.5 inches) and approximately 11 cm (4.5 inches) can be placed, but many other lengths are also possible. In another embodiment, catheters having a length of approximately 8.26 cm (3.25 inches) can be placed.

[0025] First, referring to Figures 1A-1B and 2A-2B, these illustrate various details of a catheter insertion tool ("insertion tool"), generally referred to as 10, according to one embodiment. As shown, the insertion tool 10 has a housing 12, which then includes an upper housing portion 12A that is detachably fitted to a bottom housing portion 12B. A needle hub 14 supporting a hollow needle 16 is sandwiched between the housing portions 12A and 12B. The needle 16 extends distally from the needle hub 14 so as to extend through the body of the insertion tool 10 and exit from the distal end of the housing 12. In another embodiment, the needle is at least partially hollow, while still enabling the functions described herein.

[0026] A notch 18 is defined to penetrate the wall of the needle 16, close to the distal end of the needle 16. Once access to the patient's vascular system is achieved during the catheter insertion procedure, the notch 18 allows backflow of blood from the lumen defined by the hollow needle 16. Thus, as will be further described below, the clinician can observe the blood flowing out of the notch 18 to confirm proper needle placement within the vascular system.

[0027] The insertion tool 10 further includes a guidewire advancement assembly 20 for advancing a guidewire 22 through the needle 16 into the patient's vascular system after needle access has been achieved. The guidewire 22 is pre-positioned within the lumen of the needle 16 with its proximal end positioned close to the proximal end of the needle hub 14, as is best seen in Figures 1B and 2A. The guidewire advancement assembly 20 includes a guidewire lever 24, which selectively advances the guidewire distally during use of the insertion tool 10 so that the distal portion of the guidewire extends beyond the distal end of the needle 16. The guidewire lever 24 includes a lever tab 26, which engages with the proximal end of the guidewire to push the guidewire 22 through the lumen of the needle 16.

[0028] The guidewire advance assembly 20 further includes a slide 28 slidably mounted to the upper housing portion 12A. Two tabs 24A of the guidewire lever 24 are operably mounted to the slide 28 so that selective movement of the slide by the user results in a corresponding movement of the lever 24, and consequently, a corresponding movement of the guidewire 22. The engagement of the lever tabs 24A with the slide 28 also maintains the attachment of the slide to the housing 12. Of course, other engagement methods can be employed to translate user input into movement of the guidewire. To enable the sliding movement of the slide 28 and the lever 24, the upper housing portion 12A includes a suitable track, which includes a track 34 extending to the distal end of the housing 12.

[0029] The slide 28 includes two arms 30 that partially wrap around a rail 32 defined by the housing 12. In particular, during the initial distal advance of the slide 28, the arms 30 slide on the bottom housing rail 32A, as best seen in Figure 5B. During further distal advance of the slide 28, the arms 30 slide beyond the bottom housing rail 32A to the upper housing rail 32B, as best seen in Figures 2A and 3A. Once the arms 30 of the slide 28 are no longer engaged with the bottom housing rail 32A, the two housing portions 12A and 12B can be separated, as further described below.

[0030] The guidewire lever 24 includes a locking arm 36, which is elastically positioned to spring up and engage with an extension 36A defined inside the upper housing portion 12A when the slide 28 is fully slid distally. This prevents accidental retraction of the guidewire 22 after it has been extended distally, otherwise the distal portion of the guidewire may be unintentionally severed by the distal tip of the needle 16 during insertion. It should be noted that, in one embodiment, the engagement of the locking arm 36 with the extension 36A can provide the user with tactile and / or audible feedback indicating that the guidewire 22 has been fully extended distally.

[0031] The insertion tool 10 further includes a catheter advancement assembly 40 for selectively advancing a catheter 42, which is pre-positioned within the housing 12 and includes a catheter tube 44 and a hub 46 at its proximal end, distally. As seen in Figures 1A and 1B, the catheter 42 is initially partially pre-positioned within a volume defined by the housing 12 such that the lumen of the catheter tube 44 is positioned over a needle 16, which in turn is positioned over the guidewire 22, as described above.

[0032] In particular, the catheter advancement assembly 40 includes a handle 48 defining a base 48A and two arms 50 extending from the handle base. Each arm 50 defines a grip surface 50A, a finger grip 50B, and one of two teeth 50C. The grip surface 50A and the finger grip 50B allow the handle to be grasped or contacted by the user to selectively advance the catheter 42 distally while using the insertion tool 10 to insert the catheter into the patient's body. The teeth 50C engage with corresponding raised surfaces on the hub 46 to detachably connect the handle 48 to the catheter 42.

[0033] The catheter advancement assembly 40 includes additional components related to the handle 48. A plug or valve 52 is sandwiched between the handle base 48A and the catheter hub 46 to prevent blood from spilling when the catheter is first introduced into the patient's vascular system. A safety housing 54 containing a needle safety component 56 is detachably attached to the handle 48 between the arms 50. Specifically, to detachably secure the safety housing to the handle 48, projections 60 included on the inner surface of the handle arms 50 engage with corresponding recesses 62 (Figure 10A) defined in the safety housing 54. A cap 58 supports the needle safety component 56 and covers the end of the safety housing 54. As shown in Figure 1B, the needle 16 initially extends through the aforementioned components in the order shown in Figure 2B. Further details regarding the operation of these components are given below. The cap 58, safety housing 54, and needle safety component 56 can be combined to define a safety assembly.

[0034] In one embodiment, it should be noted that the outer diameters of the needle 16 and catheter tube 44 are lubricated with silicone or other suitable lubricant to improve the sliding of the catheter tube against the needle and to assist in the insertion of the catheter into the patient's body.

[0035] The insertion tool 10 further includes a support structure 70 for stabilizing the needle 16 near the exit point from the housing 12. In this embodiment, the support structure 70 includes an interface 72 between the upper housing portion 12A and the bottom housing 12B, which is molded to closely match the round shape of the needle 16 and the catheter tube 44. The interface 72 stabilizes the needle 16 to prevent excessive "play" of the needle, thereby improving the user's precision when initially accessing the patient's vascular system.

[0036] As is most commonly seen in Figure 2A, the upper housing 12A, needle hub 14, and bottom housing 12B include engaging features 68 for maintaining the attachment of the proximal end of the housing 12 even when the more distal portion of the housing is separated, as described below. However, it should be noted that various types, sizes, and numbers of engaging features can be employed to achieve this desired function.

[0037] Figures 3A to 9 illustrate the various stages of using the insertion tool 10 when placing the catheter 42 into the patient's vascular system. For clarity, the various stages are shown without depicting the actual insertion into the patient. With the insertion tool 10 in the configuration shown in Figure 1A, the user holding the insertion tool 10 first guides the distal portion of the needle 16 through the skin to a suitable insertion site and access a subcutaneous vessel. Confirmation that proper vascular access has been achieved is evident via backflow, i.e., by the presence of blood between the outer diameter of the needle 16 and the inner diameter of the catheter tube 44, with blood flowing out from the hollow interior of the needle through the notch 18. Note that in one embodiment, the presence of blood in the safety housing 54, which is a translucent housing in one embodiment, can function as a secondary backflow indicator, as blood enters the housing from the needle 16 when a vessel is accessed.

[0038] After needle access to the blood vessel is confirmed, the guidewire advancement assembly 20 is activated, and the slide 28 is advanced by the user's finger to advance the guidewire 22 (Figures 3A and 3B), which is initially positioned within the hollow needle 16, distally. Note that the guidewire is advanced distally by a lever 24 that is operablely attached to the slide 28. Also note that during the distal advancement of the slide 28, the slide arm 30 of the slide 28 moves along the rails 32 on each side of the housing 12, i.e., first along the bottom housing rail 32A and then along the upper housing rail 32B.

[0039] The distal advance of the guidewire continues until the slide 28 slides distally for its entire length, resulting in a predetermined length of the guidewire 22 extending beyond the distal end of the needle 16, as shown in Figures 4A and 4B. In one embodiment, as shown in Figure 4B, the lever tab 26 contacts the distal portion of the needle hub 14 to prevent further distal advance of the slide 28. Figures 5A and 5B show that once the slide 28 has fully advanced distally, the slide arm 30 of the slide 28 no longer engages with the bottom housing rail 32A and engages only with the upper housing rail 32B. This then allows for the separation of housing portion 12A and housing portion 12B, as will be further seen below.

[0040] As shown in Figures 5A and 5B, after the guidewire 22 has been fully extended within the patient's blood vessel (Figures 4A and 4B), the catheter advancement assembly 40 is activated, and the handle 48 is advanced distally by the user so that the catheter tube 44 slides over the distal portion of the needle 16 and guidewire 22 and enters the patient's vascular system through the insertion site. Figures 6A and 6B show that once the catheter is advanced by the handle 48, the housing portion 12A and the housing portion 12B are easily separated, allowing the catheter hub 46 to exit from the distal end of the housing 12, and allowing the catheter to be inserted into the patient's vascular system to a suitable extent.

[0041] As shown in Figures 7A and 7B, during the removal of the catheter from the housing 12 of the insertion tool 10, it should be noted that the catheter slides distally along the needle 16 until the distal needle tip is received into the safety housing 54 and engages with the needle safety component 56. Figure 8 shows that the insertion tool 10 can be separated from the catheter 42 while the handle 48 remains attached to the catheter hub 46. As described above, the handle 48 includes a valve 52 sandwiched between the catheter hub 46 and the handle 48. Once the needle 16 and safety housing 54 are removed from the catheter 42, the valve 52 closes the catheter lumen to prevent accidental spillage of blood from the catheter hub 46. As shown in Figure 9, the handle 48 can be disengaged from the catheter hub 46 by pulling, twisting, etc., to disengage the teeth 50C of the handle from the hub. The extension leg can be attached to the catheter hub, and the catheter 42 can be dressed according to standard procedures. Afterward, the housing 12 and handle 48 of the insertion tool 10 can be discarded.

[0042] Figures 10A to 10C show details of the safety housing 54 and the needle safety component 56, and further details of the interaction between the needle safety component 56 and the needle 16 when isolating the distal end of the needle 16. As shown in the figures, the safety housing 54 is configured to allow the needle 16 to pass through the safety housing 54 and exit the housing via an extension 74 at the distal end of the housing, as described. The cap 58 is located within the proximal end of the safety housing 54 and is configured to support the needle safety component 56 so that the needle 16 first passes through the safety housing, the cap, and the needle safety component. Note that the extension 74 of the safety housing 54 in this embodiment extends into the valve 52 to open the valve when the insertion tool 10 is in use, thereby eliminating undesirable friction between the valve and the needle.

[0043] Figure 10C shows that the needle safety component 56 includes a bent or fixed element 80 through which the needle first penetrates and extends, and a friction element 82. As seen in Figure 10A, when the needle 16 is withdrawn from the catheter 42 (Figure 8), the distal tip of the needle is withdrawn proximally through the extension 74, over the distal portion of the needle safety component, thereby preventing the needle from contacting the needle safety component. This allows the friction element 82 to slightly tilt the fixed element 80, thereby fixing the needle 16 in place, preventing further movement of the needle relative to the safety housing 54, and isolating the distal tip of the needle within the housing to prevent accidental needle stick injuries. In this embodiment, the friction element 82 includes an O-ring of a suitable size. A suitable O-ring can be obtained, for example, from Apple Rubber Products (NY, Lancaster). Further details relating to needle safety components, their operating principles, and similar devices are disclosed in U.S. Patents 6,595,955, 6,796,962, 6,902,546, 7,179,244, 7,611,485, and 7,618,395, each of which is incorporated herein by reference in its entirety. Of course, other needle safety devices can be employed to isolate the distal end of the needle.

[0044] Here, in describing a catheter insertion tool 110 according to one embodiment, we will refer to Figures 11A to 13B. Note that various features in this embodiment and subsequent embodiments are the same as those already described in relation to the above embodiment. Therefore, only selected aspects of each embodiment will be described below.

[0045] The insertion tool 110 includes a housing 112 defined by an upper housing portion 112A and a bottom housing portion 112B, both of which partially surround the catheter 42. A needle hub 114 supporting a distally extending needle 116 is included so as to be positioned within the housing 112, and the catheter tube 44 of the catheter 42 is positioned above the needle. It should be noted that in this embodiment and other embodiments, the partial surrounding of the catheter by the insertion tool allows the clinician to manipulate the insertion tool by hand closer to the distal end of the needle than is normally possible.

[0046] Figures 13A and 13B show further details of the needle hub 114 attached to the upper housing portion 112A. A needle holder 126, included at the distal end of the needle hub 114, receives the proximal end of the needle 116 therein. The needle 116 is fixed within the needle holder 126 by adhesive, welding, or other preferred means. Extensions 128 are included on both sides of the needle holder 126 and are configured to be slidably received in corresponding slots 130 defined on the sides of the bottom housing portion 112B. Such engagements allow the bottom housing portion 112B to slide distally relative to the upper housing portion 112A.

[0047] The upper rail 132 is included on the needle hub 114 and is configured to engage with a corresponding slot 134 defined within the proximal portion of the upper housing portion 112A, thereby securing the needle hub to the upper housing portion. The lockout arm 136 is also included on the needle hub 114 and is positioned to engage with the rear plate 124 when the bottom housing portion 112B is slid distally to extend the guidewire from the needle 116, thereby preventing the guidewire from being retracted. Note that, as best seen in Figure 11D, the guidewire 122 initially extends distally from the rear plate 124 through the needle holder 126 and the needle 116.

[0048] The guidewire advancement assembly 120 is included to selectively advance the guidewire 122, which is initially positioned within the lumen of the needle, distally beyond the distal end of the needle 116. The guidewire advancement assembly 120 includes a bottom housing portion 112B, to which the guidewire 122 is attached at its proximal posterior plate 124. As can be seen in the figure, the bottom housing portion 112B is distally slidable relative to the upper housing portion 112A to allow selective distal advancement of the guidewire 122.

[0049] The insertion tool 110 further includes a catheter advancement assembly 140 for selectively advancing the catheter 42 over the needle 116. The advancement assembly 140 includes a handle 146, which is initially slidably positioned between the upper housing 112A and the bottom housing 112B and is detachably attached to the hub 46 of the catheter 42. As best seen in Figures 12A and 12B, the handle 146 includes two arms 150 to allow the user to selectively slide the handle to advance the catheter 42. The handle 146 further includes a recess 152, within which a needle safety component 156 is located for isolating the distal tip of the needle 116 when the needle is withdrawn from the catheter 42. Further details relating to needle safety components are disclosed in U.S. Patents 6,595,955, 6,796,962, 6,902,546, 7,179,244, 7,611,485, and 7,618,395, each incorporated by the above reference.

[0050] The insertion tool 110 further includes a support structure 170 for stabilizing the needle 116 near the distal end of the housing 112. In this embodiment, the support structure 170 includes two flaps 172 hinged to the distal portion of the bottom housing portion 112B. When closed, as seen in Figures 11D and 12A, the flaps 172 stabilize the needle 116 and function to assist the user of the insertion tool 110 in inserting the needle into the patient. When open (Figure 14D), the flaps 172 provide an opening that allows the catheter hub 46 to be removed from the distal end of the housing 112, as will be further detailed below. Before the bottom housing portion 112B is slid relative to the upper housing portion 112A, the flaps 172 are positioned within a track 174 defined by the upper housing portion. Other types and configurations of support structures may also be employed. The insertion tool 110 further includes grip surfaces 176 on both sides of the housing 112 to assist in the use of the tool during catheter insertion procedures, as detailed below.

[0051] Figures 14A to 14E illustrate the various stages of using the insertion tool 110 when inserting a catheter into a patient. With the insertion tool 110 in the configuration shown in Figure 14A, vascular access is achieved by the user inserting the needle 116 into the patient at the insertion site. Confirmation of vascular access can be achieved by observing backflow through the distal notch of the needle 116, as described in the previous embodiment, or by other preferred methods.

[0052] Once the distal portion of the needle 116 is positioned within the patient's blood vessel, the guidewire 122 is extended beyond the distal end of the needle and enters the blood vessel by advancing the bottom housing portion 112B distally. Such advancement is achieved in this embodiment by placing the user's finger on the folded flap 172 of the bottom housing portion 112B and pushing the flap distally, thereby extending the guidewire 122. The guidewire 122 is advanced until it is fully extended. The lockout arm 136 of the needle hub 114 then engages with the rear plate 124 of the bottom housing portion 112B, preventing the guidewire 122 from being retracted.

[0053] At this stage, the handle 146 of the catheter advancement assembly 140 is advanced distally by the user grasping one or both arms 150 of the handle 146 to advance the catheter 42 distally through the insertion site into the patient's vascular system. This is shown in Figure 14C, which shows the catheter tube 44 advancing distally over the needle 116 and guidewire 122.

[0054] As shown in Figure 14D, continued distal advancement of the catheter 42 biases the catheter hub 146 to open the flap 172, thereby providing a suitable opening that allows the hub to pass through the opening from the insertion tool housing 112. Note that the flap 172 is shaped so that, as seen in Figure 14D, contact with the catheter hub 46 biases each flap to fold outward. Also note that full distal advancement of the guidewire 122 by applying pressure to the flap 172 with a finger, as described above, prevents the flap 172 from being positioned within the track 174.

[0055] Figure 14E shows that the upper housing portion 112A and the lower housing portion 112B can be separated at their distal ends so that the handle 146, which is still attached to the catheter hub 46, can be separated from the housing 112 when the flap is no longer engaged in the track 174. Although not shown at this stage, a needle safety component 156 located in a recess 152 of the handle 146 isolates the distal end of the needle 116. The handle 146 can then be manually removed from the catheter hub 46 (Figure 14F) to complete the placement and dressing of the catheter 42. The insertion tool 110, including the needle 116 isolated by the needle safety component 156 of the handle 146, can be safely disposed of.

[0056] Referring now to Figure 15, Figure 15 shows an exploded view of a catheter insertion device 10 according to one embodiment, which includes components similar to those already described above. Therefore, only the selected differences will be described below.

[0057] Figure 15 shows that in this embodiment, the guidewire 22 is folded back over itself in a loop shape to define a substantially U-shaped configuration. Figures 17A and 17B show how the guidewire 22 is positioned within the housing 12 of the catheter insertion device 10. In particular, these figures show that the proximal end of the guidewire 22 is fixed to a portion of the device 10, i.e., at an anchor point 982 on the upper part 12A of the housing 12. Figure 18 shows that the guidewire 22 extends proximal and detachably within a guide channel 984 defined on the inner surface of the upper housing portion 12A. Figures 17A and 17B show that the middle portion of the guidewire 22 is folded back over itself in a loop shape close to the proximal end of the device 10. A guide surface 980 (Figure 16) located near the proximal end of the guidewire lever 24 restrains the flexible guidewire 22 to form a loop-shaped, substantially U-shaped configuration. Next, the looped middle portion of the guidewire 22 extends toward the distal end of the device 10 along the channel 986, most commonly shown in Figure 19, which is defined on the inner surface of the bottom housing portion 12B of the housing 12, before entering the hollow needle 16. The free distal end of the guidewire 22 is initially inside the needle 16.

[0058] As described above, when positioned, the guidewire 22 is positioned to be selectively advanced by the guidewire advance assembly 20, thereby allowing the free distal end of the guidewire 22 to extend distally from the open distal tip of the needle 16. This selective advance of the guidewire 22 is achieved in this embodiment by the distal movement of a guidewire advance slide 28 contained in the device housing 12. The distal movement of the guidewire advance slide 28 causes a corresponding distal sliding movement of the guidewire lever 24. The guide surface 980 of the guidewire lever 24 pushes the bent portion of the guidewire 22 distally as the lever advances. It should be noted that the guidewire 22 is sufficiently rigid to be advanced by the guidewire lever 24 without buckling. Furthermore, the guide surface 980 and the guidewire 22 are configured to allow the guidewire 22 to be pulled back into the insertion tool housing 12 when the guidewire advance slide 28 or other preferred mechanism is slid proximal.

[0059] This pushing motion of the sliding guidewire lever 24 causes the distal end of the guidewire 22 to extend distally from the open distal tip of the needle 16. Because the proximal end of the guidewire 22 is fixed to the anchor point 982 and its configuration is U-shaped or looped, in the device configurations of Figures 1A to 9, it advances distally at approximately twice the sliding speed of the guidewire advance slide 28 and approximately twice the guidewire advance speed, resulting in a guidewire extension length approximately twice the travel length of the guidewire advance slide 28. This, more preferably, results in a relatively long guidewire extension into a vein or other patient blood vessel to more favorably guide the catheter 42 into the patient's body. Thus, the guidewire and advance assembly described herein operates as a kind of “reverse pulley” system for distal guidewire advancement. Note that other loop configurations of the guidewire may be included in the device 10 in addition to those illustrated and described herein. In other embodiments, different ratios are possible between the extension of the guide wire and the movement of the forward assembly.

[0060] It should be noted that the loop-shaped conduit and guidewire advance handle are merely examples of structures capable of suitably performing the desired functions described herein. In fact, other structures can be employed to realize the principles described in relation to this embodiment. Also, although the proximal end of the guidewire is illustrated and described above as being attached to the catheter insertion device housing, it may be attached to other structures within / on the device, such as the needle hub 14. In one embodiment, the majority of the guidewire length consists of a nickel-titanium metal alloy commonly called nitinol, which is sufficiently rigid and can be arranged in a U-shape configuration without retaining memory of its position when the guidewire is advanced. It should be noted that other suitable guidewire materials can also be employed.

[0061] Figures 20A and 20B show various details of the needle safety component 56 for protecting the distal tip of the needle 16 after catheter insertion is complete, and further details relating to the aforementioned fixing element 80. As shown in the figures, the fixing element 80 (also referred to herein as the fixing member) includes a front plate 992 defining a hole 992A and a fork-shaped rear plate 994. A projection 996 extends from one of the forks of the rear plate 994. A horseshoe-shaped needle passage element 998 is also included, spaced apart from the front plate 992, defining a hole 998A coaxially aligned with the hole 992A in the front plate.

[0062] Furthermore, a friction element 1000, also referred to herein as a friction member, is included in the fixing element 80 in this embodiment, and the friction element 1000 is, namely, an annular elastomer element or an O-ring 1002, as shown in Figures 21A and 21B. As shown, the O-ring 1002 is configured to wrap around both a portion of the needle 16 and a fork-shaped rear plate 994. A projection 996 is employed to help maintain the O-ring 1002 in place, as shown in Figures 21A and 21B. As will be further described below, with the O-ring 1002 in this position, a relatively constant biasing force is applied to the fixing element 80 by the O-ring for use in protecting the distal tip of the needle 16. It should be noted that elastomer elements can take forms other than O-rings while performing the same function. For example, a rod made of elastomer material wrapped around a portion of the fixing element and the needle, or an elastomer material of a certain length, could also be employed.

[0063] Figures 21C and 21D show a fixed element 80 positioned within the carriage 1008, which is then positioned within the safety housing 54. As shown, the carriage 1008 defines two restraining surfaces 1010, and when the needle 16 first extends through the carriage and the fixed element, the corresponding portion of the front plate 992 of the fixed element first contacts these restraining surfaces. A retaining ring 1008A through which the needle 16 slides enables engagement between the needle and the carriage 1008.

[0064] The fixing element 80 is initially positioned to slide with the needle 16 in the state shown in 21A-21D (showing before the fixing element protects the distal tip of the needle) so that relative sliding movement between the needle and the fixing element is permitted. The tilting movement of the fixing element 80 is initially restricted as the needle 16 passes through the hole 998A of the needle passage element 998.

[0065] The needle 16 also passes through the hole 992A in the front plate 992 so that the fork of the fork-shaped rear plate 994 straddles the needle. As described above, the O-ring 1002 is positioned around the needle 16 and the rear plate 994 to provide a resistive force when the carriage 1008 and the fixing element 80 (both housed within the safety housing 54 (Figure 15)) are slid distally along the length of the needle 16 during use of the device 10. The resistive force provided by the O-ring 1002 during such distal sliding then imparts a rotational moment to the fixing element 80 (by force provided by the contact between the fixing element and the O-ring), biasing the fixing element to rotate in a clockwise motion from the viewpoint of the figure shown in Figure 21C.

[0066] Such clockwise rotation of the fixing element 80 is prevented by the needle passage feature 998 while the needle 16 extends through the fixing element. However, if the safety housing 54 that holds the carriage 1008 and the fixing element 80 slides distally a sufficient distance so that the needle passage feature 998 slides and disengages beyond the distal end of the needle 16, the fixing element is no longer constrained, and the resistive force provided by the O-ring 1002 causes the fixing element to tilt clockwise relative to the needle from the viewpoint shown in the figure 21C. This tilt locks the movement of the fixing element 80, and consequently the carriage 1008, relative to the needle 16 by physical coupling between the outer surface of the needle 16 and the periphery of the front plate hole 992A, and as a result acts as a coupling surface. Thus, the distal end of the needle 16 is safely positioned within the locked carriage 1008, protecting the user from accidental needle puncture.

[0067] As described above, the O-ring 1002 provides a relatively constant biasing force to tilt the retaining element 80, which keeps the retaining element tilted (after the distal tip of the needle has been withdrawn into the carriage as described above) so as to more securely lock the carriage 1008 onto the distal tip of the needle 16. This constant biasing force is beneficial, for example, when the needle 16 is pushed back and forth against the safety housing 54 / carriage 1008 after the needle 16 has been locked onto the distal tip, ensuring that the retaining element does not return to a position that would allow the needle passage feature 998 to re-engage with the needle 16 and unlock the needle safety component 56. It should be noted that the O-ring 1002 may be used with needles and retaining elements that are larger or smaller than those illustrated and described herein.

[0068] The O-ring 1002 in the above embodiments is sufficiently flexible to stretch across the aforementioned structure while applying the desired force, as described above. In one embodiment, the material of the O-ring 1002 includes any one or more of natural or synthetic rubber, elastomers, polymers, thermoplastics, silicones, etc. In one embodiment, the material of the O-ring is selected to provide sufficient tear resistance, the ability to apply the desired friction, and chemical compatibility. The size of the O-ring may vary depending on the size and configuration of the fixing element and needle. In other embodiments, the O-ring may include other shapes, materials, and positional arrangements while still providing the intended function.

[0069] Figure 22A shows that the guidewire lever 24 may include a catheter advancement feature, which, in addition to advancing the guidewire 22 as described above, allows the guidewire lever to advance the catheter 42 distally. In this embodiment, the catheter advancement feature includes an advancement tab 1014, which is positioned on the proximal portion 24A of the guidewire lever 24 and is positioned to physically engage with the cap 58 of the safety housing 54 when the guidewire lever 24 is moved distally by the user sliding the slide 28 distally (Figure 15). Such engagement is shown in Figure 22B. Further distal movement of the guidewire lever 24 results in distal advancement of the safety container 54 and the catheter 42 (Figure 15), which is indirectly but operably attached to the safety container 54. In this embodiment, the slide 28 can be slid to advance the catheter 42 distally by a predetermined distance via the advancement tab 1014 of the guidewire lever 24. In one embodiment, the catheter 42 is advanced by a predetermined distance until its distal end advances distally over the distal tip of the needle 16. Further distal advancement of the catheter 42 can be achieved, if necessary, by distal sliding of the handle 48 (Figure 15). In another embodiment, the slide 28 is configured to advance the catheter distally by the required total distal distance via the advance tab 1014.

[0070] The position of the advance tab 1014 in Figure 22A is such that it provides stepwise advancement of the guidewire 22 and catheter 42. In particular, distal advancement of the guidewire lever 24 from the position shown in Figure 22A immediately advances the guidewire 22 while the safety housing 54 and catheter 42 remain in place. By advancing the guidewire lever 24 further distally to the position shown in Figure 22B, the advance tab 1014 engages with the safety housing 54 and catheter 42 as described above, advancing them distally while continuing to advance the guidewire 22 distally.

[0071] Therefore, in addition to advancing the guidewire 22 distally through the needle 16, the guidewire lever 24 can also advance the catheter 42 distally along the needle 16 and insert it into the patient's blood vessel, as further described above. It should be noted that the specific shape and configuration of the advance tab 1014, as well as the method of engagement of the advance tab 1014 with the safety housing and / or catheter, and the magnitude of the movement imparted to the safety housing and / or catheter may differ from those illustrated and described herein.

[0072] Figure 23A shows a detailed side section view of a portion of an insertion tool 10 (sometimes called a catheter insertion device assembly) incorporating a first embodiment of the mechanical gain mechanism according to several embodiments. The mechanical gain mechanism 1200 is generally configured to increase the force applied to the catheter 42 by the slide 28 (Figures 1A and 1B) or more specifically by the guidewire lever 24 of the slide 28. More specifically, the guidewire lever 24 applies an input force 1221 to the mechanical gain mechanism 1200, which then applies an output force 1222 to the cap 58 of the safety housing 54. The cap 58, safety housing 54, catheter hub 46, and catheter 42 are coupled to each other such that the cap 58, safety housing 54, catheter hub 46, and catheter 42 are displaced distally relative to the bottom housing portion 12B as a single unit, and that the distal force applied to the cap 58 is transmitted to the catheter 42 (Figure 15). During use, the user applies an input force 1221 to the slide 28, which transmits the input force 1221 to the mechanical gain mechanism 1200 via the forward tab 1014 of the guidewire lever 24. As a result, the mechanical gain mechanism 1200 applies an output 1222 to the catheter 42, displacing the catheter 42 distally along the needle 16. The mechanical gain mechanism 1200 is generally configured such that the output force 1222 is greater than the input force 1221. In some embodiments, the output force 1222 may be more than twice the input force 1221.

[0073] The mechanical gain mechanism 1200 includes a lever 1210. The lever 1210 defines a first end 1211, a second end 1212, and an intermediate point 1213 between the first end 1211 and the second end 1212. The second end 1212, together with the bottom housing portion 12B, defines a pivot point 1215. In some embodiments, the lever 1210 may include an opening 1214 through which a needle 16 passes. The opening 1214 may include a hole or a slot.

[0074] The first end 1211 is coupled to the guidewire lever 24 via a forward tab 1014 such that distal displacement of the slide 28 causes a corresponding distal displacement of the first end 1211. In other words, the forward tab 1014 transmits an input force 1221 to the first end 1211, displacing it distally relative to the bottom housing portion 12B, which then rotates the lever 1210 about the pivot point 1215. The rotation of the lever 1210 causes the midpoint 1213 to contact the cap 58 so that the midpoint 1213 applies an output force 1222 to the cap 58.

[0075] Figure 23B shows a detailed side section view of a portion of the insertion tool 10 incorporating a second embodiment of the mechanical gain mechanism according to several embodiments. The mechanical gain mechanism 1300 is generally configured to increase the force applied to the catheter 42 by the guidewire lever 24. More specifically, the guidewire lever 24 applies an input force 1321 to the mechanical gain mechanism 1300, which then applies an output force 1322 to the cap 58 of the safety housing 54. The cap 58, safety housing 54, catheter hub 46, and catheter 42 are coupled to each other such that the cap 58, safety housing 54, catheter hub 46, and catheter 42 are displaced distally relative to the bottom housing portion 12B as a single unit, and the distal force applied to the cap 58 is transmitted to the catheter 42. During use, the user applies an input force 1321 to the slide 28 (Figures 1A and 1B), and the guidewire lever 24 of the slide 28 transmits the input force 1321 to the mechanical gain mechanism 1300. As a result, the mechanical gain mechanism 1300 applies an output 1322 to the catheter 42 so as to displace the catheter 42 distally along the needle 16. The mechanical gain mechanism 1300 is generally configured such that the output force 1322 is greater than the input force 1321. In some embodiments, the output force 1322 may be more than twice the input force 1321.

[0076] The mechanical gain mechanism 1300 includes a lever 1310. The lever 1310 defines a first end 1311, a second end 1312, and an intermediate point 1313 between the first end 1311 and the second end 1312. The second end 1312, together with the needle hub 14, defines a pivot point 1315. The first end 1311 is coupled to the guidewire lever 24 via a forward tab 1014 such that distal displacement of the slide 28 causes a corresponding distal displacement of the first end 1311. In other words, the forward tab 1014 transmits an input force 1321 to the first end 1311, displacing the first end 1311 distally relative to the bottom housing portion 12B, which then rotates the lever 1310 about the pivot point 1315. The rotation of the lever 1310 causes the intermediate point 1313 to come into contact with the cap 58 so that the intermediate point 1313 applies an output force 1322 to the cap 58.

[0077] Figure 23C shows a detailed side section view of a portion of an insertion tool 10 (sometimes called a catheter insertion device assembly) incorporating a third embodiment of the mechanical gain mechanism according to several embodiments. The mechanical gain mechanism 1400 may be similar in several respects to the features and functions of the mechanical gain mechanism described above. The mechanical gain mechanism 1400 includes a lever 1410. The lever 1410 defines a first end 1411, a second end 1412, and an intermediate point 1413 between the first end 1411 and the second end 1412. The second end 1412 engages with the bottom housing portion 12B via an engaging feature 1418 such that distal displacement of the second end 1412 relative to the bottom housing portion 12B is limited or prevented. The engaging feature 1418 may include a tab, a slot, or any other preferred feature. The intermediate point 1413, together with a cap 58, defines a pivot point. The first end 1411 is coupled to the guidewire lever 24 via a forward tab 1014 such that distal displacement of the slide 28 (Figures 1A and 1B) causes a corresponding distal displacement of the first end 1411. In other words, the forward tab 1014 transmits an input force 1421 to the first end 1411, displacing it distally relative to the bottom housing portion 12B, which then rotates the lever 1410 around the pivot point 1415. The rotation of the lever 1410 causes the midpoint 1413 to contact the cap 58 so that the midpoint 1413 applies an output force 1422 to the cap 58.

[0078] Figure 23D shows a detailed side section view of a portion of an insertion tool 10 (sometimes called a catheter insertion device assembly) incorporating a fourth embodiment of the mechanical gain mechanism according to several embodiments. The mechanical gain mechanism 1500 may be similar in some respects to the features and functions of the mechanical gain mechanism described above. The mechanical gain mechanism 1500 includes a lever 1510. The lever 1510 defines a first end 1511, a second end 1512, and a bend 1519 at an intermediate point 1513 between the first end 1511 and the second end 1512. The bend 1519 defines a horizontal section of the lever 1510 extending between the intermediate point 1513 and the first end 1511, and a vertical section extending between the intermediate point 1513 and the second end 1512. The second end 1512 engages with the cap 58 such that a distal displacement of the second end 1512 causes a distal displacement of the cap 58. The midpoint 1513, together with the needle hub 14, defines the pivot point 1515. The first end 1511 is slidably coupled to the guidewire lever 24 such that the cam surface 1507 of the guidewire lever 24 causes a lateral inward / downward displacement of the first end 1511. The inward / downward displacement of the first end 1511 then causes a distal displacement of the second end 1512. In other words, the cam surface 1507 transmits an input force 1521 to the first end 1511, displacing the first end 1511 toward the bottom housing portion 12B, which then rotates the lever 1510 about the pivot point 1515. The rotation of the lever 1510 causes the second end 1512 to come into contact with the cap 58 so that it applies an output force 1522 to the cap 58. Thus, the rotation of the lever 1510 separates the cap 58 from the needle hub 14.

[0079] Figure 23E shows a detailed side section view of a portion of an insertion tool 10 (sometimes called a catheter insertion device assembly) incorporating a fifth embodiment of the mechanical gain mechanism according to several embodiments. The mechanical gain mechanism 1600 may be similar in some respects to the features and functions of the mechanical gain mechanism described above. The mechanical gain mechanism 1600 includes a tension member 1610 (e.g., a wire or cable). The tension member 1610 defines a first end 1611, a second end 1612, and a loop portion 1613 between the first end 1611 and the second end 1612. The tension member 1610 is attached at the first end 1611 to the guidewire lever 24 of the slide 28 (Figures 1A and 1B). The tension member 1610 extends proximal along the guidewire lever 24 away from the first end 1611 between the guidewire lever 24 and the safety housing 54. The loop portion 1613 partially wraps around the cap 58 and then extends distally along the bottom housing portion 12B between the safety housing 54 and the bottom housing portion 12B. The second end 1612 is attached to the bottom housing portion 12B. Distal displacement of the slide 28 pulls the loop portion 1613 distally so that the tension member 1610 slides along the cap 58. Distal displacement of the loop portion 1613 pulls the cap 58 distally as a result, so that the distal displacement of the cap 58 is half the distal displacement of the slide 28. In other words, the guidewire lever 24 applies an input force 1621 to the tension member 1610 at the first end 1611, and the loop portion 1613 applies an output force 1622 to the cap 58, which is twice the input force 1621. The cap 58 is coupled to the catheter 42 such that distal displacement of the cap causes a corresponding distal displacement of the catheter 42 relative to the bottom housing portion 12B and the needle 16. In some embodiments, when the slide 28 is in the fully retracted position, i.e., fully displaced to the right in Figure 23E, the tension member 1610 may have some slack (i.e., may not be under tension).In such embodiments, the guide wire lever 24 may not displace the cap 58 until the guide wire 22 has been inserted a specified distance.

[0080] Figure 23F shows a detailed side section view of a portion of an insertion tool 10 (sometimes called a catheter insertion device assembly) incorporating a sixth embodiment of the mechanical gain mechanism according to several embodiments. The mechanical gain mechanism 1700 may be similar in some respects to the features and functions of the mechanical gain mechanism described above. The mechanical gain mechanism 1700 includes a first gear rack 1711, a second gear rack 1712, and a pinion gear 1713 positioned between the first gear rack 1711 and the second gear rack 1712, wherein the pinion gear 1713 is configured to mesh with both the first gear rack 1711 and the second gear rack 1712. The first gear rack 1711 is coupled to the slide 28 (Figures 1A and 1B), more specifically to the guidewire lever 24 (e.g., mounted or incorporated), and the second gear rack 1712 is coupled to the bottom housing portion 12B (e.g., mounted or incorporated). Distal displacement of the slide 28 causes the pinion gear 1713 to roll along the second gear rack 1712 (i.e., rotate and displace distally along it). The pinion gear 1713 is coupled to the catheter 42 via a cap 58 such that the pinion gear 1713 and the catheter 42 are displaced distally as a single unit. The rolling of the pinion gear 1713 along the second gear rack 1712 causes a distal displacement of the pinion gear 1713, which is half the distal displacement of the slide 28. In other words, slide 28 exerts an input force 1721 around (or over) the pinion gear 1713, and the center of the pinion gear 1713 exerts an output force 1722 on cap 58, which is twice the input force 1721. Cap 58 is coupled to catheter 42 such that distal displacement of cap 58 causes a corresponding distal displacement of catheter 42 relative to the bottom housing portion 12B and needle 16.

[0081] Figure 24 is a block diagram of a method for implanting a catheter in a blood vessel, which may include all or any subset of the following steps, actions, or processes according to several embodiments. Method 1800 may include inserting the needle of a catheter insertion device assembly through the patient's skin so that the distal end of the needle is positioned in a blood vessel (block 1810). The needle is pre-positioned in the lumen of the catheter of the catheter insertion device assembly, and the guidewire of the catheter insertion device assembly is pre-positioned in the lumen of the needle. Method 1800 may further include advancing the guidewire distally along the lumen of the needle so that the guidewire extends beyond the distal end of the needle (block 1820).

[0082] Method 1800 may further include applying a first force distally to the slide (block 1830). Method 1800 may further include applying a second force distally to the catheter (block 1840), wherein the second force is greater than the first force.

[0083] Method 1800 may further include advancing the catheter distally along the needle by a catheter distance (block 1850) such that the distal end of the catheter is displaced from a position proximal to the distal end of the needle to a position distal to the distal end of the needle. In some embodiments of Method 1800, advancing the catheter distally includes displacing the slide of the catheter insertion device assembly distally relative to the housing of the catheter insertion device assembly by a slide distance, the slide distance being longer than the catheter distance.

[0084] In some embodiments of Method 1800, displacing the slide distally involves rotating a lever about a pivot point, which is coupled to the catheter hub, needle hub, or housing.

[0085] In some embodiments of Method 1800, the catheter insertion device includes a tension member having (i) a first end coupled to a slide, (ii) a second end coupled to a housing, and (iii) a loop portion coupled to a catheter. In such embodiments, distal displacement of the slide relative to the housing causes the loop portion to displace the catheter distally along the needle.

[0086] In some embodiments of Method 1800, the catheter insertion device includes (i) a first gear rack coupled to a slide, (ii) a second gear rack coupled to a housing, and (iii) a pinion gear coupled to a catheter, the pinion gear meshing with the first and second gear racks. In such embodiments, distal displacement of the slide relative to the housing causes the pinion gear to rotate and distally displace along the housing, thereby distally displacing the catheter along the needle.

[0087] Embodiments of the present invention may be embodied in other specific forms without departing from the spirit of this disclosure. The embodiments described should be considered in all respects to be merely illustrative and not limiting. The scope of the embodiments is therefore indicated not by the above description but by the appended claims. All changes within the meaning and equivalence of the claims are included within that scope.

Claims

1. A catheter comprising a catheter tube defining a catheter lumen extending between the distal end of the catheter and a catheter hub located at the proximal end of the catheter, wherein the catheter hub is located within a housing, A needle configured to be inserted into a patient between the skin surface and a blood vessel, wherein the needle defines a needle lumen extending between a distal end and a proximal end coupled to a housing, and the needle is pre-positioned within the catheter lumen such that the distal end extends beyond the distal end of the catheter and the proximal end extends proximal beyond the catheter hub, A guidewire extending between the distal end and the proximal portion of the guidewire, wherein the guidewire is pre-positioned within the lumen of the needle such that the distal end of the guidewire is positioned proximal to the distal end of the needle, and the proximal portion of the guidewire extends proximal beyond the proximal end of the needle. A slide that is displaceable along the outside of the housing, wherein the slide is coupled to the proximal portion of the guide wire such that the displacement of the slide causes the displacement of the guide wire, A mechanical gain mechanism, wherein the mechanical gain mechanism is coupled between the slide and the catheter hub such that the slide provides an input force to the mechanical gain mechanism, and the mechanical gain mechanism provides an output force to the catheter hub in response to the input force, and the output force is greater than the input force. A catheter insertion device assembly comprising the above features.

2. The assembly according to claim 1, wherein the input force and the output force are each directed distally.

3. The assembly according to claim 1 or 2, wherein the output force is twice as large as the input force.

4. The assembly according to any one of claims 1 to 3, wherein the displacement of the slide causes simultaneous displacement of the catheter and the guidewire.

5. The assembly according to claim 4, wherein the displacement of the catheter is smaller than the simultaneous displacement of the guidewire.

6. The assembly according to any one of claims 1 to 5, wherein the mechanical gain mechanism includes a lever.

7. The assembly according to claim 6, wherein the lever includes an opening, and the needle passes through the opening.

8. The aforementioned lever is The first end connected to the slide, The second end portion, which defines the pivot point together with the bottom housing portion, The intermediate point connected to the catheter hub, Includes, The assembly according to claim 6, wherein distal displacement of the slide relative to the bottom housing portion causes distal displacement of the catheter relative to the needle.

9. The aforementioned lever is The first end connected to the slide, A second end that defines the pivot point together with the hub of the aforementioned needle, The intermediate point connected to the catheter hub, Includes, The assembly according to claim 6, wherein distal displacement of the slide relative to the bottom housing portion causes distal displacement of the catheter relative to the needle.

10. The aforementioned lever is The first end connected to the slide, The second end of the needle is connected to the hub, An intermediate point connected to the catheter hub, wherein the intermediate point defines a pivot point, Includes, The assembly according to claim 6, wherein distal displacement of the slide relative to the bottom housing portion causes distal displacement of the catheter relative to the needle.

11. The aforementioned lever is The first end is slidably coupled to the cam surface of the slide, The second end connected to the catheter hub, The intermediate point adjacent to the bent portion of the lever that defines the pivot point together with the hub of the needle, Includes, The assembly according to claim 6, wherein distal displacement of the slide relative to the bottom housing portion causes lateral displacement of the first end, which in turn causes distal displacement of the catheter relative to the needle.

12. The mechanical gain mechanism is The first end connected to the slide, The second end is connected to the bottom housing portion, The loop portion connected to the catheter hub, Includes a tension member having, The assembly according to any one of claims 1 to 11, wherein the distal displacement of the slide relative to the bottom housing portion causes the loop portion to displace the catheter distally to the needle.

13. The mechanical gain mechanism is A first gear rack coupled to the slide, A second gear rack connected to the bottom housing section, A pinion gear coupled to the catheter hub, wherein the pinion gear meshes with the first gear rack and the second gear rack, Includes, The assembly according to any one of claims 1 to 12, wherein the distal displacement of the slide relative to the bottom housing portion rotates the pinion gear, causing it to displace distally along the bottom housing portion, and as a result the catheter co-displaces distally with the needle together with the pinion gear.

14. The assembly according to any one of claims 1 to 13, further comprising a safety assembly configured to cover the distal end of the needle when the needle is withdrawn from the catheter, wherein the safety assembly is coupled between the catheter hub and the mechanical gain mechanism such that distal displacement of the slide causes distal displacement of the safety assembly, which in turn causes distal displacement of the catheter.

15. The slide is configured to be displaced by a first distance and a subsequent second distance. The displacement of the slide by the first distance causes the guide wire to be displaced distally to the needle by the first guide wire distance. The displacement of the subsequent second distance of the slide is The guide wire is displaced distally from the needle by the second guide wire distance, The catheter is displaced from the needle by a first catheter distance, and the first catheter distance is shorter than the second guidewire distance. The assembly according to any one of claims 1 to 14.

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