Tearaway sheath assembly with hemostasis valve.

(54) Title: COVER ASSEMBLY THAT STARTS WITH A HEMOSTATIC VALVE.

(54) Title: TEARAWAY SHEATH ASSEMBLY WITH HEMOSTASIS VALVE.

(57) Summary

A tear-off sleeve assembly (100) having a detachable sleeve tube (102), a detachable hub (110), a detachable valve (150), and a separator cap (180) ; the valve (150) is of the elongated duckbill type and has a slot (158) almost entirely through the distal end wall (154) such that the two diverging sides (156) of the distal valve portion they may move away during insertion through a dilator or catheter; a two-part cap (180) is attached to the proximal end of the tube (120) and traps a valve seat flange (168) between itself and a seat notch (136) in the hub; opposing pairs of gaps (184,122) in cap (180) and hub (110) are aligned with brittle sections or seams (108) of casing tube (102) and brittle sections (172) and grooves (166) of the valve facilitate the separation of the assembly (100) when the doctor wishes to detach it from the inserted catheter.

(57) Abstract

A tearaway sheath assembly (100) having a splittable sheath tube (102) a splittable hub (110), a splittable valve (150) and a split cap (180). The valve (150) is of the elongated duckbill type and having a slit (158) almost completely across the distal end wall (154) such that two diverging sides (156) of the distal valve portion may be moved apart during insertion therethrough of a dilator or a catheter. A two-part cap (180) is affixed to the hub proximal end (120) and traps a seating flange (168) of the valve between itself and a seating groove (136) of the hub. Pairs of opposed gaps (184,122) of the cap (180) and the hub (110) are aligned with frangible sections or seams (108) of the sheath tube (102) and frangible sections (172) and slits (166) of the valve , facilitating splitting of the assembly (100) when desired by the practitioner peel it away from the inserted catheter.

COVER ASSEMBLY THAT STARTS WITH VALVE

HEMOSTATIC

DESCRIPTIVE MEMORY

The invention relates to medical devices and more particularly devices for use in insertion and implantation of catheters and the like in the vasculature of patients.

Catheters are used in numerous medical procedures. In particular, catheters are used for the introduction or removal of fluids from various venous regions and vessels through the body such as for hemodialysis. The procedure by which these catheters are introduced into the body is delicate and complex. A particularly difficult challenge for catheterization is dilating a hole in the skin and vessel to be catheterized while decreasing blood loss and trauma to the patient. Generally, to insert any catheter into a blood vessel, the vessel is identified by aspiration with a long hollow needle according to the Seldinger technique. When blood enters a syringe attached to the needle, indicating that the vessel has been found, then a thin guide generally is inserted through the syringe needle or other introducer device into the vessel. The introducer device is then detached leaving the guide inside the glass. The guide is projected beyond the surface of the skin.

At this point, several options are available to clinicians for catheter placement. The simplest option is to pass a catheter in the vessel directly over the guide. The guide then comes off. However, the use of this technique is only possible in cases where the catheter is of a relatively small diameter made of a rigid material and not significantly larger than the guide. However, if the catheter is of a relatively large diameter and / or is not made of a soft material, a preferable method of catheter insertion into the vessel is through an introducer sheath. The introducer sheath is simply a large, rigid, thin-walled tube that serves as a temporary conduit for the catheter to be placed. The sheath is placed by means of a dilator, which has a hollow duct along its longitudinal axis within the sheath and passes through the dilator and sheath along with the vessel on the guide. The dilator expands the opening in the blood vessel to allow insertion of the catheter into the vessel. The guide and dilator are then detached leaving the thin-walled sleeve in place. The catheter is then inserted into the vessel through the sleeve.

In a place where a catheter with a hub or other junction at the proximal end of the catheter has the characteristic that it is larger than the sheath's internal diameter, it is necessary to have a tear-off sheath that can detach from the catheter while the sheath comes off the patient. An example of such a sheath that is torn off or detachable or removable with the dilator is set forth in US Patent No. 6,796,991 which is shown here in the prior art of Figures 1 and 2 thereof. By separating the sheath along its longitudinal axis while the sheath is detached from the patient, the inserting physician will be able to pull the sheath in such a way that the detached portion of the patient is detached, thereby not interfering with any impediment in the catheter. Generally, the tear-off sleeves are made in a manner that aids in tearing the sheath at two opposite points on the circumference of the sheath thereby separating the sheath into two halves longitudinally through the center of the sheath.

A sheath is generally constructed with a cube at its proximal end. This bucket serves as a handle, a match point for a dilator, and a flat surface to aid in the prevention of blood loss or contamination. When a sheath needs to be detached to successfully remove it from the body while leaving the catheter in place, the hub will also need to be detached to clean the catheter. Preferably, the hub is separated along the same lines as the sheath. To accomplish this, the cube must be designed with projections or other unreinforced parts along two longitudinal lines aligned with the unreinforced parts in the sheath. Some previous examples of these unreinforced parts are flanges, or nets that connect two halves of the hub or indentations in the material that comprises the hub. The unreinforced parts in the bucket will help the inserting doctor break the bucket in line with the seams that are torn off the sheath.

Another important facet of the cube is a set of tabs or flaps that protrude from the center. These tabs not only help the inserting doctor align, insert, and detach the sheath, but also pull the sheath so that the sheath can detach from around a catheter while the catheter is still left in place. There are a number of different tab configurations, but it is important to have one that allows for easy manipulation, control and leverage. One design includes a hub where the flanges protrude from the hub perpendicular to a plane which includes the seams that are torn off the sheath and the longitudinal axis of the sheath. In this design, the tabs are diametrically opposed to each other and are separated in such a way that when the tabs grip and separate from them, the sleeve and its hub will separate downwards in half. Another desirable feature of the eyelashes is that the eyelashes provide leverage to break the cube in a way that does not cause trauma to the incision in the body.

During insertion, especially in the time between shedding of the dilator from the sheath and insertion of the catheter through the sheath, loss of blood through the sheath or introduction of contaminants or air through the sheath is possible and in the glass. For this reason, it is desired that the measures taken prevent blood, air, or contaminants from traveling through the sheath. In the past, inserting physicians simply had to hold their thumb over the opening at the proximal end of the sheath; however, a more reliable and permanent means of preventing blood, air, or contaminants from traveling through the sheath is desired. Therefore, it is desired that the hub include a valve located in the sheath. Such a valve would facilitate insertion of objects such as a catheter, dilator, or syringe through the sheath while restricting blood loss and reducing the opportunity for contaminants to enter the patient's blood stream when the sheath is not attached. with a dilator or catheter.

In the case where a sheath does not have a small diameter or narrow point, the dilator is generally used to help insert the sheath. The dilator has a long tubular insert, the outer diameter of which is slightly smaller than the inner diameter of the sheath. The dilator also has a pointed tip at its distal end and a hollow center which runs the full length of the dilator. The dilator is inserted into the body with a guide leading to its center, allowing the tip of the dilator to follow the guide to the place to be catheterized. At its proximal end, the dilator may have a hub. Like the sleeve hub, this hub also serves a number of purposes, such as providing stable handling to help guide the dilator into the vein and a mechanism that can be adjusted with the sleeve hub to form a blocked connection.

In Figures 1 and 2 of the prior art, a removable locking dilator and a sheath assembly and methods for detaching the dilator from the sheath and longitudinally separating the sheath are provided. The Assembly Includes a dilator that has a dilator hub and a sleeve that has a sleeve hub. The sheath hub has a valve and two opposing butterfly tabs, each tab has a perpendicular portion and an angular portion as well as a female threaded portion. The dilator hub has a male threaded portion designed to engage the female threaded portion of the sleeve hub. The dilator detaches from the sleeve by rotating the dilator 90 ° relative to the sleeve and pulling the dilator out of the sleeve. The sheath splits longitudinally to create a mating movement on each of the butterfly flaps thereby forcing the sheath and sheath hub to be longitudinally detached. With the sheath, valve, and sheath hub longitudinally apart, the sheath breaks off from around a catheter while leaving the catheter in place.

It is desired to provide a hemostatic valve for a detachable sheath and to provide a sheath assembly with a hemostatic valve and sheath hub for use therewith, which can be detached to facilitate detachment of the sheath from an inserted catheter.

The present invention is a starter sleeve assembly having a detachable sleeve tube and a detachable hub fixed to it, with the hub at the proximal end of the sleeve assembly, the sleeve tube. it extends to a distal end of minor diameter, a conduit that extends through the assembly from the proximal end to the distal end and defines a longitudinal axis therethrough. The sheath hub includes opposite brittle seams along the sheath to facilitate separation or detachment during the start-up procedure.

The assembly of the present invention also includes a hemostatic valve seal that can be separated contained and fixed within the hub. The hub comprises two opposing sections joined together in fragile joints or networks until intentional separation so that the hub remains intact in one piece until the physician succeeds in separating them after the catheter is incised into a patient vasculature, with a wing that can be elongate attached to each section of the hub to manipulate and to initiate separation in a manner known in the art. The cube also provides different opposing spaces between the two opposing sections that are joined into fragile sections within the spaces, where the spaces that are aligned with opposite fragile seams of the sleeve tube so that when the doctor separates the cube, the Sheath was also detached while continuing the booting procedure. A valve contained within the proximal end within the hub can also be detached when the hub is intentionally detached but otherwise remains intact to provide hemostasis; the valve can be selectively opened prior to separation to allow insertion through a dilator and after a catheter that forms a seal with and around it, but otherwise remains closed to prevent leakage of blood.

In a preferred embodiment, the detachable valve is a duckbill type and has an elongated structure with distal and proximal ends, the duckbill structure is positioned at its distal end and comprises a pair of angled side walls they converge and include a slot partially through the converging ends of the side walls and preferably through the axial center of the valve. Near the distal slot end, the valve changes to a tubular cylindrical structure at its proximal end. Preferably, a cap can be attached to the proximal end of the sheath hub to secure the valve to a tubular proximal end portion of the hub; and furthermore, the cap is preferably comprised of two separate parts along a radius aligned with the spaces of the hub and the seams of the sheath tube with each half attached to a respective section of the hub at the proximal end to prevent the physician Inhibit the separation procedure.

The hub of the sheath assembly of the present invention includes a proximal portion that contains a valve adjacent its proximal end and includes a distal portion that is attached to a proximal end of the sheath tube. The two opposite cube sections have separate opposite spaces but have brittle sections within the spaces to hold two opposite cube sections together until Intentional separation. Opposite gaps are lined with brittle sleeve tube seams.

Preferably, the brittle sections are located in a transition portion axially between the proximal hub portion and the distal hub portion and at the distal end of the proximal valve-containing portion where the tube diameter is made narrower and comprises thin network sections.

The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate the preferred embodiments of the invention and together with the general description given above and the detailed description given below serve to explain the features of the invention. In the drawings;

Figures 1 and 2 are isometric views of the prior art sheath / dilator assembly and the sheath of the assembly shown with the dilator detached;

Fig. 3 is an elongated isometric view of the liner assembly that is plucked from the present invention showing the liner hub and valve cover at the proximal end of the liner tube and the hub spaces aligned with seams of the liner tube. ;

Figure 4 is a view of the parts of the assembly of Figure 3 and also shows the valve that can be detached;

Figure 5 is a cross sectional view of the sleeve assembly in parts of Figure 4;

Figure 6 is a cross-sectional view of the hub, valve, and cap of Figure 4, assembled;

Figure 7 is an elevational view of a proximal end of the sheath assembly of Figure 3 making pairs directly into the hub space showing the location of the brittle hub networks;

Figure 8 is a cross-sectional front view of the assembly of Figure 7 rotated about 90 degrees from that of Figure 7 showing the brittle network joining the two sections of the hub; and

Figure 9 is a cross-sectional view of the sleeve assembly 5 taken just near the distal end of the detachable valve of the present invention.

In the drawings, equal numbers indicate equal elements in it. Certain terminology is used herein for convenience only and should not be construed as a limitation on the present invention. The terms "distal and" proximal refer respectively to directions near and far from the patient. The terminology includes the words specifically mentioned, derived from it and words of similar meaning. The modalities illustrated below are not intended to be exhaustive or to limit the invention to the precise form described. These embodiments were chosen and described to better explain the principle of the invention and its practical application and use, and to enable those skilled in the art to best utilize the invention.

In Figures 1 and 2 of the prior art, a sheath assembly 10 is shown comprising a dilator 12 and a sheath 14 and having a longitudinal axis L ". Dilator 12 has a dilator hub 16 at its proximal end and its distal end portion 18 extends beyond distal end 20 of sheath 14 to a distal tip 22. The sleeve 14 includes a sleeve tube 24 and a sleeve hub 26 at the proximal end of the sleeve tube and is shown in Figure 2 with the dilator detached. Sheath hub 26 is seen with graspable flaps 28 to facilitate separation initiation by the physician to detach the sheath from an insertion catheter (not shown). To facilitate separation of the sheath 14 from around the catheter, the sheath tube has a pair of opposing brittle seams 30 and a sheath hub 26 includes brittle nets along opposite spaces 32 that align with seams 30. The end Proximal 34 of sheath 14 includes a threaded locking arrangement for locking dilator hub 12 before detaching the dilator.

Sheath assembly 100 is illustrated in Figures 3 through 9. The sheath assembly includes a sheath tube 102 with a proximal end portion 104 extending to a distal end with conduit 106 (FIG. 4) extending between them defining a longitudinal axis. The sheath tube 102 includes a pair of opposing seams or brittle sections 108 that define the unreinforced parts along which the sheath tube can be easily separated after insertion of the distal portion of the catheter into the vasculature of a patient (not shown). Mainly, with respect to Figure 3, a sheath hub 110 is fixed to the proximal end portion · 104 of the sheath tube in the proximal end portion 112 of the hub. A pair of flaps or tabs 114 extend from respective opposing sections 116, 118 of hub 110 for the clinician to grasp to initiate removal of the sheath assembly to remove them from the catheter, as they are pulled toward the distal end of the sheath in such a manner. so that cube separation begins at its proximal end 120 and cube sections 116, 118 are completely separated from each other along a pair of opposing spaces 122. Also seen in FIG. 3 is a portion of a brittle section 124 positioned along the inner edge of space 122; the fragile section or networks on both sides are attached to the cube sections 116,118.

Now with respect to Figure 4, the hub 110 is separated from the sleeve tube 102; separable valve 150 is separated from hub 110 and the two halves 182 of cap 180 are separated from hub 110 and valve 150. Hub 110 includes a large diameter cylindrical portion

126 extending to its proximal end and a frustoconical transition section 128 connecting the cylindrical portion 126 to the smaller diameter distal end portion 112. The larger diameter cylindrical portion 126 defines therein a large valve receiving cavity 130. It is noted that a seat flange 132 associated with the seat of the two lid halves 180 is projected proximally from the cylindrical portion 126 and within the space 122 a seat flange 134 associated with the valve seat can be seen that can be separated 150.

The detachable valve seal 150 will now be described with respect to Figures 4 and 5. The detachable valve 150 is of the duckbill type so named because its distal end portion 152 is equal to the shape of the duck bill and extends to a transverse distal end wall 154. The distal end portion 152 has two converging side walls 156 extending towards the distal end wall 154 and a groove 158 is formed in the distal end wall 154 that extends mostly but preferably not completely through (see Figure 9 ). The cylindrical wall 160 joins the lateral ends of the lateral walls 156 and defines a large central cavity 162 that extends between the distal end wall 154 and the proximal end 164 of valve 150. It is best seen in Figure 4, grooves 166 of limited axial length cut into side wall 160 and into a seat flange 168 to facilitate valve separation. Furthermore, within the large central cavity one can see V-notches 170 formed in the cylindrical wall 160 that are aligned with and communicating with the groove 166 and are also aligned with the spaces 122 of the hub 110 and the seams 108 of the sleeve tube 102 in the finished assembly. The seating flange 168 is T-shaped in cross section forming proximal and distal seating slits 172, 174 best seen in Figures 5 and 6.

Lid 180 preferably comprises two separate but identical halves 182 for securing valve 150 within valve receiving cavity 130 of hub 110 and are attached or fused to the hub. The lid halves 182, when fastened in place to the proximal end of the hub, are separated by space 184 aligned with spaces 122 of the hub 110 and seams 108 of the sleeve tube 102 and V-notches 170 and valve grooves 166 150. Cap 180 defines a conduit 186 extending therethrough from a bevelled inlet at the proximal end of the cap with conduit 186 large enough in ID for a dilator and catheter to be movably inserted in the same. Cap 180 includes an outer flange at the proximal end defining an outer seating slit 188 into which flange 132 of hub 110 is received. An external cylindrical wall 190 extends distally towards an end portion 192 that is associated with the proximal seating groove 172 of valve 150. An internal cylindrical wall 194 along conduit 186 is spaced inward from the external cylindrical wall

190 for defining a deep seating slit 196 associated with the proximal end portion of the cylindrical wall 160 of valve 150.

The interrelation of various associated portions of the hub, valve, and cap is best explained with respect to Figures 5 and 6 for an understanding of their assembly. The valve 150 is within the large valve receiving cavity 130 of the hub 110. The distal seating groove 174 of the flange 168 is positioned or seated within the seating notch 136 defined outside of the seating flange 134 of the hub 110 . Proximal seating slit 172 of valve 150 is proximally oriented to receive therein end portion 192 of outer cylindrical wall 190 of cap 180 (see Figure 4). The proximal end portion of the cylindrical wall 160 of valve 150 is associated with the deep seating slit 196 of cap 180 between its inner and outer cylindrical walls 194, 190. Figure 5 also shows that the proximal end 138 of sheath 102 extends toward the distal end of valve receiving cavity 130 of hub 110 to increase the area of ​​attachment between the proximal end portion of the sheath and the end portion. distal

112 of the cube.

At the proximal end 120 of hub 110, seat flange 132 projects proximally to receive in the outer seat recess

188 of cap 180. By attaching or fusing cap 180 to hub 110 it joins the oriented surfaces of seat flange 132, outer seat slits 188, outer surface of outer cylindrical wall 190, and inner surface of cylindrical wall 126 of hub 110 and proximal flange 140 around seat flange 132 and distal surface 198 of cap outer flange. Cap halves 182 are attached to hub 110 in a manner that compresses seat flange 168 of valve 150 and locks in place while establishing a seal between the valve and the two cap halves and hub,

Figures 7 and 8 best show fragile sections or nets

124 hub 110 connecting hub sections 116, 118. The nets are formed along the inner surface of the hub valve receiving cavity 130 (FIG. 6) and are very thin. Preferably, they extend along the frusto-conical intermediate portion 128 of the hub and partially along the cylindrical wall 130, extending towards and along the seat flange 134. With respect to FIG. 9, it is preferred that primarily for manufacturing reasons, the spaces 122 of the hub 110 extend radially inward from the outer surfaces of the hub to the end portions of internal space 142 that are V-shaped converging on brittle nets 124 so that the mold inserts remain relatively thick, large and durable for various molding cycles and also for careful control of the thickness of the brittle nets. The nets can have a thickness, for example of about 0.0508 mm and the width W of the spaces 122 in the external surfaces can be, for example, about 1,270 mm. Similarly, as seen in Figure 9, the brittle sections 170 of the detachable valve 150 may be V-shaped in cross section but extend from the inner surface to the outer surface preferably about one-half thickness of the cylindrical wall 160.

It can be seen in Figure 9 that the distal end wall

154 of the valve would be spliced ​​via a proximal end of a guidewire (not shown) during Initial placement of the sheath assembly on the guidewire after the guidewire is placed in the vasculature, then by the distal tip of the dilator inserted at through the hub and valve and then through the catheter dlstal tip with slot 158 ​​allowing the side walls to diverge to deform as the slot opens in response to insertion of the guide, the dilator or catheter with the valve maintaining engagement with the external surfaces of the guide, dilator, or catheter as it passes therethrough; and the slot will also close against the guide with the dilator detaching from the sheath assembly forming a hemostatic seal and preventing blood spillage. The valve may be made of sllicona. The hub and lid can be made of polyethylene or polypropylene. The sleeve tube could be made of polyethylene or polytetrafluoroethylene.

Those skilled in the art will appreciate that changes can be made to the modalities described above without departing from the inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments described but is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.