JP7565009B2 - Indwelling needle with hemostasis valve and disk valve for indwelling needle - Google Patents

Description

The present invention relates to an indwelling needle with a hemostatic valve that is equipped with a hemostatic valve that prevents blood leakage when the outer needle is inserted into and left in a patient's blood vessel, and a disk valve for an indwelling needle that is used in an indwelling needle with a hemostatic valve.

Conventionally, indwelling needles have been used when administering infusions to patients or collecting blood from patients. Indwelling needles have a structure in which a cylindrical catheter adapter (outer needle hub) is provided on the base end side of a hollow catheter (outer needle), such as the catheter assembly shown in JP2012-517326 (Patent Document 1).

The catheter assembly of Patent Document 1 has a partition (disk valve) on the inner circumference of the catheter adapter, and the partition prevents blood from leaking through the catheter adapter when the catheter is inserted into a blood vessel. In addition, when an infusion line, syringe, etc. is connected to the catheter assembly that is left indwelled in the blood vessel while being inserted, the partition opens, making it possible to supply infusion to the blood vessel and collect blood from the blood vessel.

In the catheter assembly of Patent Document 1, an air passage is provided between the bulkhead and the inner surface of the catheter adapter, and the distal end side of the valve body and the proximal end side of the catheter hub are mutually connected through the air passage. As a result, when the catheter is inserted into a blood vessel, blood is permitted to flow from the blood vessel into the catheter adapter on the distal end side of the bulkhead. The insertion of the catheter into the blood vessel can be confirmed by flashback.

Special Publication No. 2012-517326

However, in a structure with such an air passage, there was a problem in that blood leaked through the air passage to the base end side of the partition. That is, the air passage is a minute passage that is sufficiently narrowed to prevent blood from entering, but it is difficult to completely prevent blood from gradually entering the air passage due to capillary action and leaking to the base end side. Therefore, there was a risk that blood would leak from the partition in the catheter adapter to the base end side before an infusion line, syringe, etc. was connected to the base end opening of the catheter adapter.

The problem to be solved by this invention is to provide an indwelling needle with a hemostasis valve of a novel structure that can delay blood leakage while allowing flashback.

Another object of the present invention is to provide a disk valve for an indwelling needle with a novel structure that can be used with an indwelling needle with a hemostatic valve to delay blood leakage while allowing flashback.

The following describes preferred embodiments for understanding the present invention. However, each embodiment described below is merely an example, and may be combined with one another as appropriate. The multiple components described in each embodiment may be recognized and used independently as far as possible, and may also be combined with any of the components described in another embodiment as appropriate. As a result, the present invention is not limited to the embodiments described below, and various alternative embodiments may be realized.

In the first aspect, in an indwelling needle with a hemostatic valve, a cylindrical outer needle hub is provided on the base end side of a hollow outer needle, and a disk valve is arranged on the outer needle hub, an air passage is provided that connects a first region on the distal side of the disk valve in the inner cavity of the outer needle hub to a second region on the proximal side of the disk valve, and a blood reservoir part whose cross-sectional area is partially enlarged in the longitudinal direction is provided in the air passage at a position away from the first region.

According to the indwelling needle with a hemostatic valve constructed according to this embodiment, the first and second regions in the inner cavity of the outer needle hub are mutually connected through the air passage, even if the inner cavity of the outer needle hub is blocked by the closed disk valve. Therefore, when blood flows into the first region through the outer needle that has been inserted into a blood vessel, air in the first region is discharged to the second region through the air passage, and the inflow of blood into the first region is permitted without being hindered by the air spring. This makes it possible to visually confirm that the outer needle has been properly inserted into the blood vessel, for example, by the inflow (flashback) of blood into the inner cavity of the outer needle or the first region of the outer needle hub.

The air passage is formed with a size and shape that makes it difficult for blood to penetrate, but if blood penetrates the first region, the blood may gradually penetrate into the air passage over time. Therefore, a blood reservoir with a partially enlarged cross-sectional area is provided in a position in the air passage away from the first region. Blood that penetrates into the air passage from the tip side is stored in the blood reservoir, so that the progress of blood toward the base end side of the blood reservoir can be delayed. Therefore, blood can be prevented from leaking to the base end side of the air passage until a medical device such as an infusion line or a syringe is connected to the base end side of the outer needle hub, and contamination due to blood leakage and malfunction of the valve mechanism can be avoided.

The second aspect is an indwelling needle with a hemostatic valve as described in the first aspect, in which a narrowed portion having a smaller cross-sectional area than the blood reservoir portion is provided on the proximal side of the blood reservoir portion in the air passage.

With an indwelling needle with a hemostatic valve constructed according to this embodiment, the narrowing portion provided on the base end side of the blood reservoir can prevent blood from leaking from the blood reservoir to the base end side, and the time required for blood to leak to the base end side can be set longer.

The third aspect is an indwelling needle with a hemostatic valve as described in the first or second aspect, in which a valve support member that sandwiches the disk valve between the outer needle hub and the valve support member and positions the disk valve relative to the outer needle hub is disposed in the inner cavity of the outer needle hub, and the air passage is formed between the inner surface of the outer needle hub and the outer surface of the disk valve and the outer surface of the valve support member.

In the indwelling needle with a hemostatic valve constructed according to this embodiment, the air passage is formed to extend not only between the disk valve and the outer needle hub but also between the valve support member and the outer needle hub, so that the passage length of the air passage can be set longer, and the time until blood leaks can be set longer.

In addition, the valve support member is a member that positions the disk valve relative to the outer needle hub, and is fixedly attached to the outer needle hub, which also stabilizes the passage shape of the air passage formed between the outer needle hub and the valve support member.

The fourth aspect is an indwelling needle with a hemostatic valve as described in the third aspect, in which a circumferentially extending recess is provided on the inner peripheral surface of the outer needle hub closer to the base end than the disk valve, and protrusions that protrude at multiple points in the circumferential direction are provided on the outer peripheral surface of the valve support member closer to the base end than the disk valve, and the valve support member is fixed to the inner surface of the outer needle hub by fitting the protrusions into the recesses, and the blood storage portion is configured to include the recesses between the multiple protrusions in the circumferential direction.

With an indwelling needle with a hemostatic valve constructed according to this embodiment, the valve support member can be easily fixed to the outer needle hub by fitting the protruding portion of the valve support member into the recess of the outer needle hub. In addition, since the blood reservoir is formed using a recess for fixing the valve support member provided on the inner surface of the outer needle hub, it is easy to ensure a large volume for the blood reservoir.

The fifth aspect is an indwelling needle with a hemostatic valve as described in the third or fourth aspect, in which an abutment portion is provided that protrudes from the inner peripheral surface of the outer needle hub and is superimposed on the tip surface of the disk valve, the inner diameter dimension of the abutment portion is made smaller than the outer diameter dimension of the tip portion of the valve support member, and the disk valve is sandwiched axially between the abutment portion and the valve support member and positioned relative to the outer needle hub.

According to the indwelling needle with a hemostatic valve constructed according to this embodiment, the disk valve is positioned relative to the outer needle hub by being axially sandwiched between the abutment portion of the outer needle hub and the tip of the valve support member. As a result, in a structure in which an air passage is provided between the inner peripheral surface of the outer needle hub and the outer peripheral surface of the disk valve, the disk valve can be positioned relative to the outer needle hub without pressing the outer peripheral surface of the disk valve excessively strongly against the inner peripheral surface of the outer needle hub, and deformation of the air passage can be prevented.

In a sixth aspect, in the indwelling needle with a hemostatic valve described in any one of the third to fifth aspects, a pusher that pushes open the disk valve is disposed in the inner cavity of the outer needle hub, and the valve support member is a guide member that guides the movement of the pusher when the pusher pushes open the disk valve.

In an indwelling needle with a hemostatic valve constructed according to this embodiment, the valve support member that positions the disk valve relative to the outer needle hub also serves as a guide member that guides the movement of the plunger, thereby reducing the number of parts. Since part of the air passage is constituted by a guide member that is fixedly provided relative to the outer needle hub and guides the movement of the plunger, the shape stability of the air passage is improved compared to when part of the air passage is constituted by a member that moves relative to the outer needle hub, such as a plunger.

The seventh aspect is an indwelling needle with a hemostatic valve, in which a cylindrical outer needle hub is provided on the base end side of a hollow outer needle and a disk valve is disposed on the outer needle hub, the disk valve has an engagement part that is pressed against the inner circumferential surface of the outer needle hub and compressed in the radial direction, and a separation part that faces away from the inner circumferential surface of the outer needle hub, a micropassage extending between the overlapping surfaces of the outer circumferential surface of the engagement part of the disk valve and the inner circumferential surface of the outer needle hub is partially formed in the circumferential direction, a microgap is formed over the entire circumference between the separation part and the outer needle hub, the micropassage and the microgap are mutually communicated, and an air passage that communicates a first region in the inner cavity of the outer needle hub that is distal to the disk valve with a second region that is proximal to the disk valve is configured to include the micropassage and the microgap.

As shown in Figure 5B of JP2012-517326A, in a structure in which a groove that opens onto the outer peripheral surface is formed over the entire axial length of the disc valve and the groove is covered by an outer needle hub to form a micro-passage-like air passage, changes in the cross-sectional area and cross-sectional shape of the air passage caused by deformation of the disc valve or the like are likely to affect the flow characteristics of the air passage. Because the air passage is a micro-passage-like long region over the entire axial length of the disc valve, changes in the cross-sectional area and cross-sectional shape of the air passage caused by deformation of the disc valve or the like become large, and for example, deformation of the disc valve may cause the air passage to become blocked.

Therefore, in the indwelling needle with hemostatic valve constructed according to this embodiment, the portion of the air passage provided between the overlapping surfaces of the inner circumferential surface of the outer needle hub and the outer circumferential surface of the disk valve is configured by a combination of thin micro-passages provided partially in the circumferential direction and micro-gaps provided around the entire circumference. Therefore, the length of the portion of the air passage formed by the micro-passages is shortened, which suppresses changes in the flow characteristics of the air passage caused by, for example, deformation of the disk valve or manufacturing errors, and prevents the air passage from being blocked.

The eighth aspect is an indwelling needle with a hemostatic valve as described in the seventh aspect, in which the fitting portion of the disk valve has a larger diameter than the separation portion, a fine groove is formed that opens onto the outer peripheral surface of the fitting portion, and the outer peripheral opening of the fine groove is covered by the outer needle hub to form the micropassage.

According to the indwelling needle with hemostatic valve constructed according to this embodiment, the fitting portion of the disk valve is fitted to the inner peripheral surface of the outer needle hub, and the opening of the fine groove formed in the fitting portion of the disk valve is covered by the outer needle hub, and a micropassage is easily formed. By shortening the micropassage, even if the micropassage is composed of a fine groove opening to the outer peripheral surface of the disk valve, the effect of deformation of the micropassage on the flow characteristics of the air passage is suppressed, and the micropassage is less likely to be blocked, so that exhaust from the first region and restriction of blood leakage in the air passage are stably achieved.

In the ninth aspect, in the indwelling needle with a hemostatic valve described in the seventh or eighth aspect, a valve support member that sandwiches the disk valve between itself and the outer needle hub to position it relative to the outer needle hub is disposed in the inner cavity of the outer needle hub, and the air passage is formed between the inner surface of the outer needle hub and the outer surface of the disk valve and the outer surface of the valve support member. With an indwelling needle with a hemostatic valve structured according to this aspect, it is possible to obtain the same effect as the third aspect.

In the tenth aspect, in the indwelling needle with a hemostatic valve described in the ninth aspect, a contact portion is provided that protrudes from the inner peripheral surface of the outer needle hub and is superimposed on the tip surface of the disk valve, and the inner diameter dimension of the contact portion is made smaller than the outer diameter dimension of the tip portion of the valve support member, so that the disk valve is sandwiched axially between the contact portion and the valve support member and positioned relative to the outer needle hub. With an indwelling needle with a hemostatic valve constructed according to this aspect, it is possible to obtain the same effect as the fifth aspect.

In an eleventh aspect, in the indwelling needle with a hemostatic valve described in the ninth or tenth aspect, a pusher that pushes open the disk valve is disposed in the inner cavity of the outer needle hub, and the valve support member is configured as a guide member that guides the movement of the pusher when the pusher pushes open the disk valve. With an indwelling needle with a hemostatic valve structured according to this aspect, it is possible to obtain the same effect as the sixth aspect.

In a twelfth aspect, in the indwelling needle with a hemostatic valve described in any one of the seventh to eleventh aspects, the disk valve comprises a valve body that is disposed to block the inner cavity of the outer needle hub and has a slit, and a cylindrical holding portion that extends from the outer periphery of the valve body toward the base end, and the tip portion of the disk valve including the valve body is the fitting portion, and the base portion of the disk valve including the cylindrical holding portion is the separation portion.

In the indwelling needle with a hemostatic valve constructed according to this embodiment, the valve body is provided in a fitting portion that fits into the outer needle hub, so that the disk valve is held by the valve body to the outer needle hub, and the slit penetrating the valve body is tightened by radial compression of the fitting portion, so that the inner cavity of the outer needle hub is blocked by the disk valve. Since the separating portion is configured to include a cylindrical holding portion that extends from the valve body to the base end, the separating portion is unlikely to affect the positioning of the valve body relative to the outer needle hub, and the disk valve is stably held by the outer needle hub.

In a thirteenth aspect, in the indwelling needle with a hemostatic valve described in any one of the seventh to twelfth aspects, a blood reservoir portion in which the cross-sectional area is partially enlarged in the longitudinal direction is provided in the air passage at a position away from the first region. With an indwelling needle with a hemostatic valve structured according to this aspect, it is possible to obtain the same effect as the first aspect.

In the fourteenth aspect, in the indwelling needle with a hemostatic valve described in the thirteenth aspect, a narrowed portion having a smaller cross-sectional area than the blood reservoir portion is provided on the proximal side of the blood reservoir portion in the air passage. With the indwelling needle with a hemostatic valve structured according to this aspect, it is possible to obtain the same effect as the second aspect.

In a fifteenth aspect, in the indwelling needle with a hemostatic valve described in the thirteenth or fourteenth aspect, a valve support member that positions the disk valve relative to the outer needle hub by sandwiching it between the outer needle hub and the valve support member is disposed in the inner cavity of the outer needle hub, a circumferentially extending recess is opened on the inner peripheral surface of the outer needle hub on the base side of the disk valve, and a protrusion that protrudes at multiple points in the circumferential direction is provided on the outer peripheral surface of the valve support member on the base side of the disk valve, and the valve support member is fixed to the inner surface of the outer needle hub by fitting the protrusion into the recess, and the blood storage portion is configured to include the recess between the multiple protrusions in the circumferential direction. With an indwelling needle with a hemostatic valve structured according to this aspect, it is possible to obtain the same effect as the fourth aspect.

The sixteenth aspect is a disk valve for an indwelling needle that is disposed in the inner cavity of an outer needle hub and switches the inner cavity between a communicating state and a blocked state, and has a large-diameter fitting portion that is fitted into and supported by the outer needle hub, and a separation portion that is smaller in diameter than the fitting portion and spaced apart from the inner peripheral surface of the outer needle hub, which are continuous in the axial direction, and a fine groove that opens onto the outer peripheral surface is formed in the fitting portion, and the end opening of the fine groove is open toward the outer periphery of the separation portion.

According to the disk valve for indwelling needles constructed according to this embodiment, the fitting portion of the disk valve is fitted to the inner peripheral surface of the outer needle hub, and the opening of the fine groove formed in the fitting portion of the disk valve is covered by the outer needle hub, and a micropassage is easily formed. The air passage, which includes the micropassage formed between the disk valve and the outer needle hub by the fine groove of the fitting portion and the microgap formed between the disk valve and the outer needle hub by the separation portion, is shortened by providing the separation portion in the disk valve. Therefore, even if the micropassage is formed by the fine groove formed on the outer peripheral surface of the disk valve, the effect of deformation of the micropassage on the flow characteristics of the air passage is suppressed, and the micropassage is less likely to be blocked, thereby realizing stable exhaust and limiting blood leakage in the air passage.

According to the present invention, in an indwelling needle with a hemostasis valve, it is possible to delay blood leakage while allowing flashback.

FIG. 1 is a perspective view showing an indwelling needle with a hemostatic valve according to a first embodiment of the present invention; FIG. 7 is a cross-sectional view of the indwelling needle with a hemostatic valve shown in FIG. 1, which corresponds to the cross section II-II of FIG. 6 is a cross-sectional view of the indwelling needle with a hemostasis valve shown in FIG. 1 , which corresponds to the cross-section of FIG. FIG. 2 is a perspective view of a disk valve constituting the indwelling needle with a hemostasis valve shown in FIG. FIG. 2 is a perspective view of a plunger guide constituting the indwelling needle with a hemostatic valve shown in FIG. FIG. 3 is an enlarged cross-sectional view taken along the line VI-VI of FIG. FIG. 7 is an enlarged view of a cross section taken along the line VII-VII of FIG. FIG. 2 is a cross-sectional view showing a state in which a male connector is connected to the indwelling needle with a hemostasis valve of FIG.

The following describes an embodiment of the present invention with reference to the drawings.

Figures 1 to 3 show an indwelling needle with a hemostatic valve (hereinafter, indwelling needle) 10 as a first embodiment of the present invention. The indwelling needle 10 has an outer needle hub 14 provided on the base end side of the outer needle 12, and has a structure in which a disk valve for an indwelling needle (hereinafter, disk valve) 16 is housed in the outer needle hub 14. In the following explanation, as a general rule, the tip side refers to the left side in Figure 2, and the base side refers to the right side in Figure 2.

The outer needle 12 is a hollow tube with a small diameter that allows it to be inserted into a body lumen such as a blood vessel. The outer peripheral surface of the tip portion of the outer needle 12 is tapered, and the diameter decreases toward the tip. The outer needle 12 may be made of metal, but is preferably made of synthetic resin and is flexible.

The outer needle hub 14 has a generally cylindrical shape with a larger diameter than the outer needle 12. The outer needle hub 14 has a smaller diameter at the tip portion than at the base end portion, and the outer needle 12 is inserted into the inner cavity 18 of the outer needle hub 14 at the tip portion. As shown in Figs. 2 and 3, the outer needle 12 of this embodiment is fixed to the outer needle hub 14 by being sandwiched between the outer needle hub 14 and a funnel-shaped fixing pin 20 fitted into the outer needle hub 14, but the outer needle 12 and the outer needle hub 14 may be fixed by means of, for example, ultrasonic welding. The inner peripheral surface of the base end portion, which has a larger diameter, is a luer taper that expands toward the base end side, and a male connector 78, which will be described later and which has a luer taper on the outer peripheral surface, can be connected by fitting. The base end of the outer needle hub 14 is provided with a male threaded portion 22 that protrudes to the outer periphery, and a locking portion provided on an infusion line or syringe (not shown) equipped with a male connector 78 is screwed into the male threaded portion to prevent the infusion line, syringe, etc. from coming off the outer needle hub 14.

The outer needle hub 14 has an abutment portion 24 that protrudes from the inner circumferential surface on the proximal side of the fixing pin 20. The proximal surface of the abutment portion 24 is an annular abutment surface 26 that extends in the axial direction.

A groove 28 is formed on the inner peripheral surface of the outer needle hub 14. The groove 28 is formed continuously around the entire circumference of the outer needle hub 14. The groove 28 has both axial side surfaces that are inclined axially outward toward the inner circumference, and the axial width dimension of the opening portion is larger than the axial width dimension of the bottom portion. The groove 28 in this embodiment extends in the circumferential direction with a substantially constant cross-sectional shape, but the cross-sectional shape may vary in the circumferential direction. The groove 28 is provided on the base end side, which has a larger diameter than the tip portion of the outer needle hub 14 to which the outer needle 12 is fixed. The groove 28 is provided at a position away from the abutment portion 24 toward the base end side.

A disk valve 16 is disposed in the axially middle portion of the inner cavity 18 of the outer needle hub 14. The disk valve 16 is formed from rubber or resin elastomer that exhibits rubber-like elasticity. As shown in Figures 2 to 4, the disk valve 16 is integrally structured to include a substantially disk-shaped valve body 30 and a cylindrical retaining portion 32 that extends from the outer peripheral end of the valve body 30 toward the base end.

The valve body 30 has a slit 34 that penetrates the central portion in the axial direction. In this embodiment, the slit 34 is shaped to extend radially from the center in three directions as shown in FIG. 4, but it may be shaped like a line or a cross, for example, and each radially extending portion may be inclined circumferentially toward the radially outward direction, or the penetration direction may be inclined relative to the axial direction. The central portion of the valve body 30 protrudes toward the base end side more than the outer peripheral end, and the outer peripheral end is thinner in the axial direction (left and right direction in FIG. 2) than the central portion.

The cylindrical retaining portion 32 extends from the outer peripheral end of the thin-walled valve body 30 toward the base end. The tip portion of the cylindrical retaining portion 32 that connects to the valve body 30 is located on the outer periphery away from the central portion of the thick-walled valve body 30, and an annular circumferential groove 36 that opens toward the base end is formed between the tip portions of the cylindrical retaining portion 32 and the central portion of the valve body 30. The side wall surface on the inner periphery of the circumferential groove 36 is a tapered surface that slopes inward toward the base end and becomes smaller in diameter.

The disk valve 16 has a tip portion including the valve body 30 that has a larger outer diameter than the base portion including the base end of the cylindrical holding portion 32, with the larger diameter tip portion being the fitting portion 38 and the smaller diameter base portion being the separation portion 40. In this embodiment, the fitting portion 38 is configured to include not only the valve body 30 but also the tip portion of the cylindrical holding portion 32. The fitting portion 38 and the separation portion 40 are provided continuously in the axial direction.

A narrow groove 42 is formed in the fitting portion 38 of the disk valve 16. The narrow groove 42 opens onto the outer peripheral surface over the entire axial length of the fitting portion 38, and its tip opens onto the tip surface of the outer peripheral end of the valve body 30. In other words, the narrow groove 42 is provided continuously from the tip surface of the outer peripheral end of the disk valve 16 to the base end of the outer peripheral surface of the fitting portion 38. The base end of the narrow groove 42 opens onto a step surface 44 formed by the difference in outer diameter between the fitting portion 38 and the separation portion 40, and is open onto the outer peripheral side of the separation portion 40.

The disk valve 16 is inserted into the outer needle hub 14 from the base end side, and as shown in Figures 2 and 3, the outer peripheral end of the distal end surface abuts against the annular abutment portion 24 protruding from the inner surface of the outer needle hub 14, thereby positioning the disk valve 16 in the axial direction relative to the outer needle hub 14. In addition, the outer diameter dimension of the fitting portion 38 of the disk valve 16 is slightly smaller than the inner diameter dimension of the outer needle hub 14 that houses the fitting portion 38, and the fitting portion 38 is fitted into the inner surface of the outer needle hub 14, thereby positioning the disk valve 16 relative to the outer needle hub 14.

The valve body 30 of the disk valve 16 is radially tightened and compressed by being fitted into the outer needle hub 14, and the inner surfaces of the slits 34 penetrating the valve body 30 are pressed against each other to close the slits 34. As a result, when the disk valve 16 is attached to the outer needle hub 14, it is in a closed state in which the inner cavity 18 of the outer needle hub 14 is blocked. By disposing the disk valve 16 in the inner cavity 18 of the outer needle hub 14 in a closed state, the inner cavity 18 of the outer needle hub 14 is divided into a first region 46 on the tip side of the valve body 30 of the disk valve 16 and a second region 48 on the base side of the valve body 30.

The disk valve 16 is also positioned relative to the outer needle hub 14 by the valve support member 50. The valve support member 50 is a hard member made of synthetic resin or the like, and as shown in FIG. 5, is generally cylindrical in shape. The outer diameter of the tip portion of the valve support member 50 is smaller than that of the base end portion, and the tip portion is provided with a pressing protrusion 52 that protrudes toward the outer periphery over the entire circumference. The inner peripheral surface of the tip portion of the valve support member 50 is a tapered surface that slopes toward the outer periphery and becomes larger toward the tip, and the inner peripheral surface of the tip portion is tapered to correspond to the inner peripheral side surface of the circumferential groove 36 in the disk valve 16.

The base end portion of the valve support member 50 is provided with recessed small diameter portions 54 that open toward the outer periphery at multiple locations in the circumferential direction. In this embodiment, four small diameter portions 54 are provided in the circumferential direction. An annular flange-shaped portion 56 that protrudes radially outward from the outer periphery of the small diameter portion 54 is provided on the base end side of the small diameter portion 54 in the base end portion of the valve support member 50. A rib-shaped portion 58 that protrudes radially outward from the outer periphery of the small diameter portion 54 is provided between the four small diameter portions 54 in the circumferential direction of the base end portion of the valve support member 50 and extends in the axial direction. In this embodiment, the flange-shaped portion 56 and the rib-shaped portion 58 have approximately the same protruding height from the small diameter portion 54, and the protruding tip surface of the flange-shaped portion 56 and the protruding tip surface of the rib-shaped portion 58 are smoothly and continuously provided without any steps. An inner flange-shaped portion 60 that protrudes toward the inner periphery is provided at the base end of the valve support member 50. The base end of the valve support member 50, which is provided with the inner flange portion 60, has a tapered inner circumferential surface whose inner diameter gradually increases toward the base end.

The rib-shaped portions 58 provided between the small diameter portions 54 in the circumferential direction are provided with protruding portions 62 that further protrude toward the outer periphery. The protruding portions 62 are approximately trapezoidal when viewed in the circumferential direction, and the protruding height dimension is larger in the axial middle portion than at both ends. The imaginary cylindrical surface on which the tip faces of all the protruding portions 62 are located has a larger diameter than the bottom surface of the recessed groove 28 that opens into the inner circumferential surface of the outer needle hub 14. The protruding portions 62 are provided at the tip portions of the rib-shaped portions 58 that extend in the axial direction. The protruding portions 62 are shorter in the axial direction than the rib-shaped portions 58, and are formed in a range that does not reach the base end of the valve support member 50. The small diameter portions 54 and the protruding portions 62 are provided alternately in the circumferential direction. The small diameter portions 54 have a larger circumferential width dimension than the protruding portions 62.

The valve support member 50 is inserted into the inner cavity 18 of the outer needle hub 14 from the base end side of the disk valve 16. The protrusion 62 of the valve support member 50 is fitted into the recessed groove 28 of the outer needle hub 14 at a position away from the disk valve 16 toward the base end side, thereby fixing the valve support member 50 to the outer needle hub 14. As shown in FIG. 2, the flange-shaped portion 56 and the rib-shaped portion 58 of the valve support member 50 fixed to the outer needle hub 14 are slightly spaced from the inner circumferential surface of the outer needle hub 14.

The valve support member 50 fixed to the outer needle hub 14 has its small-diameter tip portion overlapped with the inner circumferential surface of the cylindrical holding portion 32 of the disk valve 16. The tip portion of the valve support member 50 is then fitted into the circumferential groove 36 of the disk valve 16. As a result, the cylindrical holding portion 32 is radially sandwiched between the outer needle hub 14 and the tip portion of the valve support member 50 at the fitting portion 38 of the disk valve 16, and the disk valve 16 is positioned relative to the outer needle hub 14 by the valve support member 50.

The outer diameter dimension R of the pressing protrusion 52 provided at the tip of the valve support member 50 is larger than the inner diameter dimension r of the abutment portion 24 (abutment surface 26) provided on the outer needle hub 14, and the tip surface of the pressing protrusion 52 and the abutment surface 26, which is the base end surface of the abutment portion 24, face each other in the axial direction. The bottom of the circumferential groove 36 in the disk valve 16 is sandwiched in the axial direction between the pressing protrusion 52 and the abutment portion 24, and the disk valve 16 is also positioned relative to the outer needle hub 14 by the valve support member 50. In this way, by sandwiching the disk valve 16 in the axial direction between the outer needle hub 14 and the valve support member 50, the disk valve 16 can be effectively positioned relative to the outer needle hub 14 even if the disk valve 16 is not fitted in a state where it is tightly fastened radially to the outer needle hub 14.

A plunger 64 is inserted into the inner circumference of the valve support member 50. The plunger 64 is generally cylindrical. The tip portion of the plunger 64 is tapered so that the diameter gradually decreases toward the tip side. The base end side of the taper-shaped tip portion of the plunger 64 has a smaller outer diameter than the base end of the tip portion. As a result, the base end of the tip portion is an annular engagement portion 66 that protrudes to the outer circumference, and the outer diameter of the base end of the engagement portion 66 is larger than the inner diameter of the tip of the inner flange portion 60 provided on the valve support member 50.

The plunger 64 is inserted into the valve support member 50 from the base end side. The plunger 64 is inserted into the valve support member 50 until the engagement portion 66 overcomes the inner flange-shaped portion 60 of the valve support member 50 and is positioned distally of the inner flange-shaped portion 60. The plunger 64 is positioned axially relative to the outer needle hub 14 by the distal end surface abutting the proximal end surface of the valve body 30 of the disk valve 16 and the proximal end surface of the engagement portion 66 overlapping the distal end surface of the inner flange-shaped portion 60 of the valve support member 50.

The indwelling needle 10 constructed in this manner is inserted into the patient's blood vessel together with the outer needle 12, with the inner needle (not shown) being inserted through the outer needle 12. The inner needle is then withdrawn, and the outer needle 12 is left in the blood vessel while still puncturing it. In order to prevent the outer needle 12 from falling out of the blood vessel or the outer needle hub 14 from moving unnecessarily, the outer needle 12 and the outer needle hub 14 of the left indwelling needle 10 may be fixed to the patient's body surface with, for example, medical adhesive tape.

When the outer needle 12 is inserted into a blood vessel, blood flows from the blood vessel through the outer needle 12 into the inner cavity 18 of the outer needle hub 14. The blood that has flowed into the outer needle hub 14 is prevented from moving toward the base end by the disk valve 16, and accumulates in the first region 46 on the distal side of the disk valve 16. The outer needle hub 14 is transparent or translucent, and by visually checking the inflow of blood (flashback) into the first region 46, it can be confirmed that the outer needle 12 has properly punctured the blood vessel. For example, by visually checking the blood flowing through the inner cavity of the outer needle 12, it is also possible to confirm that the outer needle 12 has properly punctured the blood vessel, and the inflow of blood into the inner cavity of the outer needle 12 may be regarded as flashback.

When blood flows into the first region 46, the air in the first region 46 is discharged to the second region 48 through the ventilation passage 68. As shown in FIG. 3, the ventilation passage 68 is formed between the outer needle hub 14 and the disk valve 16 and the valve support member 50, and connects the first region 46 and the second region 48 to each other.

More specifically, the air passage 68 has a tip portion provided between the overlapping surfaces of the outer needle hub 14 and the disk valve 16. As shown in Figs. 3 and 6, the opening portion of the fine groove 42 provided in the fitting portion 38 of the disk valve 16 is covered by the outer needle hub 14, so that the fine passage 70 is partially formed in the circumferential direction. In addition, the outer peripheral surface of the separation portion 40 of the disk valve 16 faces the inner peripheral surface of the outer needle hub 14 at a slight radial distance, so that a fine gap 72 is formed around the entire circumference between the outer needle hub 14 and the separation portion 40. The fine passage 70 and the fine gap 72 are mutually connected, and the tip portion of the air passage 68 is formed by the fine passage 70 and the fine gap 72. The tip end of the fine groove 42 that opens on the tip surface of the valve body 30 extends to the inner circumference beyond the abutment portion 24 of the outer needle hub 14, and is open to the first region 46 at the inner circumference beyond the abutment portion 24.

The base end portion of the valve support member 50 located on the base end side of the cylindrical holding portion 32 of the disk valve 16 is separated from the protruding portion 62 fitted to the outer needle hub 14 toward the inner peripheral side with respect to the inner peripheral surface of the outer needle hub 14 as shown in Figs. 3 and 7 at the portion detached from the protruding portion 62 fitted to the outer needle hub 14. As a result, a base end portion of an air passage 68 is provided radially between the outer needle hub 14 and the valve support member 50. The base end portion of the air passage 68 provided between the outer needle hub 14 and the valve support member 50 is connected to the second region 48 through the radial gap between the outer needle hub 14 and the flange-shaped portion 56 of the valve support member 50.

The ventilation passage 68, which connects the first region 46 and the second region 48 in the lumen 18 of the outer needle hub 14, is formed by connecting the tip portion provided between the outer needle hub 14 and the disk valve 16 with the base portion provided between the outer needle hub 14 and the valve support member 50. Since the ventilation passage 68 is formed not only between the outer needle hub 14 and the disk valve 16 but also extending to between the outer needle hub 14 and the valve support member 50, it is possible to set the passage length of the ventilation passage 68 long, and it is possible to delay the leakage of blood through the ventilation passage 68, which will be described later. In addition, by forming the base portion of the ventilation passage 68 between the hard outer needle hub 14 and the valve support member 50, it is possible to increase the shape stability of the ventilation passage 68 and to set the flow resistance of air and blood in the ventilation passage 68 to a high level.

The ventilation passage 68 has a blood reservoir 74 in which a portion of the length is partially enlarged in cross-sectional area. That is, the small diameter portion 54 at the base end portion of the valve support member 50 has a radial distance from the outer needle hub 14 that is greater than the radial distance between the outer needle hub 14 and the disk valve 16 at the micropassage 70 and the microgap 72. As a result, the ventilation passage 68 has a blood reservoir 74 in which the passage cross-sectional area in the direction perpendicular to the passage length is larger than other portions between the small diameter portion 54 of the valve support member 50 and the outer needle hub 14 in the radial direction. The radial width dimension of the blood reservoir 74 is greater than the radial width dimension of the micropassage 70 and the microgap 72, and further the radial facing surface distance between the outer needle hub 14 and the rib-shaped portion 58 and the flange-shaped portion 56. In this embodiment, the blood reservoir 74 includes a portion that is formed using the groove 28 of the outer needle hub 14, and the volume of the blood reservoir 74 is ensured to be large by the groove 28.

At the tip side of the blood reservoir 74 in the air passage 68, a tip-side narrowed portion having a small cross-sectional area is provided, which is composed of a micropassage 70 and a microgap 72. At the base side of the blood reservoir 74 in the air passage 68, a base-side narrowed portion 76 is provided as a narrowed portion narrowed between the flange-shaped portion 56 of the valve support member 50 and the outer needle hub 14. The tip-side narrowed portion and the base-side narrowed portion 76 both have a smaller cross-sectional area than the blood reservoir 74, and in particular, the inside dimensions in the radial direction are smaller. The blood reservoir 74 is provided at a position away from both the first region 46 and the second region 48. In this embodiment, the rib-shaped portion 58 of the valve support member 50 and the outer needle hub 14 are separated, and the blood reservoirs 74 provided in the circumferential direction are mutually communicated through the radial space between the rib-shaped portion 58 and the outer needle hub 14.

The distance between the disk valve 16 and the outer needle hub 14 at the tip-side narrowed portion (micropassage 70 and microgap 72) of the ventilation passage 68 is set so as to allow air to be discharged and restrict blood from entering, and is preferably set to, for example, 5 μm or more and 500 μm or less. In this embodiment, in the portion where the ventilation passage 68 is formed, the distance between the tip surface of the disk valve 16 and the abutment surface 26 of the outer needle hub 14 is made larger than the distance between the outer peripheral surface of the disk valve 16 and the inner peripheral surface of the outer needle hub 14. In short, the narrow groove 42 constituting the tip portion of the ventilation passage 68 has a depth dimension of the portion opening to the tip surface of the disk valve 16 larger than the depth dimension of the portion opening to the outer peripheral surface of the disk valve 16. This realizes efficient introduction of air from the first region 46 to the ventilation passage 68, and sets a sufficiently large flow resistance so that blood does not easily pass through the tip-side narrowed portion. However, the distance between the disk valve 16 and the outer needle hub 14 where the air passage 68 is formed may be constant in the longitudinal direction.

Similarly, the distance between the valve support member 50 and the outer needle hub 14 at the base-side narrowing portion 76 of the air passage 68 is desirably, for example, 5 μm or more and 500 μm or less. In addition, the distance between the valve support member 50 and the outer needle hub 14 at the base-side narrowing portion 76 may vary in the longitudinal direction.

By providing a tip-side narrowing portion at the tip side of the blood reservoir 74 in the air passage 68, the blood reservoir 74 is provided away from the first region 46 of the inner cavity 18 of the outer needle hub 14 toward the base end side, and the inflow of blood from the first region 46 to the blood reservoir 74 is restricted.

The tip narrowed portion is formed by a fine groove 42 in which the fine passage 70, which is the tip portion, opens onto the outer peripheral surface of the fitting portion 38, and is formed by fitting the disk valve 16 into the outer needle hub 14, so that the outer peripheral opening of the fine groove 42 is covered by the outer needle hub 14. In this way, the fine passage 70, which has a small passage cross-sectional area, is formed in a simple manner by simply assembling the disk valve 16 to the outer needle hub 14.

When the fitting portion 38 is compressed radially by fitting to the outer needle hub 14, the longer the passage length of the micropassage 70, the more susceptible the passage shape of the micropassage 70 is to the influence of the tightening of the fitting portion 38. Therefore, the tip portion (tip narrowing portion) of the air passage 68 formed between the disk valve 16 and the outer needle hub 14 is composed of a combination of the micropassage 70 and the micro gap 72, and the passage length of the micropassage 70 is shorter than when the micropassage 70 is provided over the entire axial length of the disk valve 16. As a result, even if the fitting portion 38 is compressed radially by fitting to the outer needle hub 14, the risk of substantial blocking due to partial dimensional errors, etc., and the risk of substantial blocking due to increased flow resistance of the micropassage 70 due to overcompression can be reduced, and the passage shape of the micropassage 70 can be stabilized.

By providing the base-end narrowing portion 76 on the base side of the blood reservoir 74 in the air passage 68, blood stored in the blood reservoir 74 does not immediately flow out into the second region 48, and leakage of blood into the second region 48 is suppressed. In particular, by providing the base-end narrowing portion 76, leakage of blood into the second region 48 is restricted regardless of the orientation of the indwelling needle 10 at the time of puncture.

By providing such an air passage 68, when blood flows into the first region 46, the air in the first region 46 moves through the air passage 68 to the second region 48. Since the second region 48 is open to the external space through the proximal end opening of the outer needle hub 14, the air is discharged to the external space.

The shape and size of the air passage 68 are set so that blood does not easily penetrate, but blood that has flowed into the first region 46 gradually penetrates into the air passage 68 over time. When the blood that has penetrated into the air passage 68 reaches the blood reservoir 74, the progress of the blood toward the base end side is suppressed by a drop in pressure until the blood reservoir 74 is filled, and blood leakage to the base end side through the air passage 68 is prevented for a predetermined time. The time required for blood to leak to the base end side can be appropriately set, for example, depending on the volume of the blood reservoir 74, and is set in consideration of the time required from the puncture of the blood vessel with the outer needle 12 to the connection of an infusion line, a syringe, or the like to the outer needle hub 14. In this embodiment, the blood reservoir 74 is configured to include a recessed groove 28 that opens to the inner circumferential surface of the outer needle hub 14, so that the degree of freedom in setting the volume of the blood reservoir 74 is increased, and it is possible to set, for example, the time required for blood to leak to the base end side longer. The volume of the blood reservoir 74 between the distal narrowed portions 70, 72 and the proximal narrowed portion 76 is desirably set to, for example, 0.1 ^mm3 or more and 100 ^mm3 or less.

In this way, by restricting the leakage of blood to the base end side (second region 48) through the air passage 68, it is possible to prevent the leaked blood from adhering to the plunger 64 and coagulating, thereby interfering with the operation of the plunger 64, and to prevent blood leaking from the outer needle hub 14 to the base end from adhering to the user, patient, other medical instruments, etc., causing contamination.

As shown in FIG. 8, when a male connector 78 provided on an infusion line, a syringe, or the like is inserted and connected to the base end side of the outer needle hub 14, the pusher 64 is pushed toward the tip side by the male connector 78. The pusher 64 pushed by the male connector 78 pushes open the slit 34 of the disk valve 16 and is inserted into the slit 34. This opens the slit 34 of the disk valve 16, and the first region 46 and the second region 48 located on both axial sides of the valve body 30 are mutually communicated through the pusher 64 inserted into the slit 34, and the disk valve 16 is in an open state in which the inner cavity 18 of the outer needle hub 14 is in a communicating state. Then, the first region 46 in the inner cavity 18 of the outer needle hub 14 is connected to the male connector 78 through the cylindrical pusher 64, and the inner cavity of an infusion line, a syringe, or the like (not shown) equipped with the male connector 78 is communicated to a blood vessel via the pusher 64, the outer needle hub 14, and the outer needle 12. When the plunger 64 is pushed toward the distal end by the male connector 78, it slides against the valve support member 50, thereby guiding its movement toward the distal end. Thus, the valve support member 50 not only functions to position the disk valve 16 relative to the outer needle hub 14, but also functions as a guide member that guides the movement of the plunger 64 toward the distal end relative to the outer needle hub 14. Since the male connector 78 is connected to the plunger 64 before the disk valve 16 is opened, the first region 46 is connected to the inner cavity of the male connector 78 inserted into the second region 48 through the plunger 64 inserted into the slit 34.

When the male connector 78 of an infusion line, syringe, or the like is connected to the outer needle hub 14, the base end opening of the outer needle hub 14 is blocked by the male connector 78, so that the second region 48 is in a substantially sealed state, and blood is prevented from entering the second region 48 through the air passage 68. Also, as shown in FIG. 8, the disk valve 16, which is pushed open by the plunger 64 and elastically deformed, covers the opening of the air passage 68 to the first region 46, thereby preventing blood or medicinal liquid from entering the air passage 68 from the first region 46 and preventing leakage to the base end side through the air passage 68.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the specific description. For example, the disk valve 16 may not have a cylindrical holding portion 32, and the entire disk valve 16 may be composed of a valve body 30 having a substantially circular disk shape.

In the above embodiment, an example was shown in which the ventilation passage 68 was formed between the inner surface of the outer needle hub 14 and the outer surface of the disk valve 16 and the outer surface of the valve support member 50, but for example, the ventilation passage 68 may be provided only between the inner surface of the outer needle hub 14 and the outer surface of the disk valve 16. The ventilation passage 68 may also be provided between the outer needle hub 14 and a member other than the disk valve 16 and the valve support member 50. In addition, the micro passage 70 and the micro gap 72 provided between the inner surface of the outer needle hub 14 and the outer surface of the disk valve 16 were formed by the outer shape of the disk valve 16, but they can also be formed by the inner shape of the outer needle hub 14, for example, by providing a groove or an enlarged diameter portion on the inner surface of the outer needle hub 14. In this case, the thin groove 42 of the fitting portion 38 and the separation portion 40 having a smaller diameter than the fitting portion 38 may not be provided in the disk valve 16.

In the above embodiment, the tip portion of the air passage 68 formed between the outer needle hub 14 and the disk valve 16 is provided with a micropassage 70 and a microgap 72. However, for example, the entire tip portion of the air passage 68 may be formed of a micropassage 70 that is partially provided in the circumferential direction. It is preferable that the air passage 68 is provided so as to extend between the overlapping surfaces of two parts, such as between the outer needle hub 14 and the disk valve 16, but it is also possible to configure the air passage 68 to include, for example, a through hole that penetrates the disk valve 16. The passage cross section of the air passage 68 may be approximately constant in the passage length direction in the portion excluding the blood reservoir 74.

The blood reservoirs 74 may be provided at multiple locations along the length of the air passage 68. In this case, the multiple blood reservoirs 74 may have different shapes and volumes, or may have the same shape and volume.

By providing a breathable filter on the passage of the air passage 68 that allows air to pass but limits the passage of liquid, leakage of blood and other substances through the air passage 68 to the base end side can be prevented for a longer period of time.

The base-end narrowing portion 76 is not essential, and the blood reservoir portion 74 may be open to the second region 48. In this case, the indwelling needle 10 with hemostasis valve is used with the base-end side of the outer needle hub 14 facing vertically upward (including diagonally upward) so that blood stored in the blood reservoir portion 74 does not immediately leak into the second region 48.

REFERENCE SIGNS LIST 10 Indwelling needle with hemostatic valve 12 Outer needle 14 Outer needle hub 16 Disk valve for indwelling needle 18 Inner cavity 20 Fixing pin 22 Male threaded portion 24 Abutment portion 26 Abutment surface 28 Concave groove 30 Valve body 32 Cylindrical holding portion 34 Slit 36 Circumferential groove 38 Fitting portion 40 Separation portion 42 Narrow groove 44 Step surface 46 First region 48 Second region 50 Valve support member (guide member)
52 Pressing protrusion 54 Small diameter portion 56 Flange-shaped portion 58 Rib-shaped portion 60 Inner flange-shaped portion 62 Projection portion 64 Pusher 66 Engagement portion 68 Air passage 70 Micro passage 72 Micro gap 74 Blood storage portion 76 Base end side narrowed portion (narrowed portion)
78 Male connector

Claims (4)

In an indwelling needle with a hemostatic valve, a cylindrical outer needle hub is provided on the base end side of a hollow outer needle, and a disk valve is disposed on the outer needle hub,
an air passage is provided that communicates a first region on the distal end side of the disk valve in the inner cavity of the outer needle hub with a second region on the proximal end side of the disk valve;
The air passage has a blood reservoir part having a cross-sectional area partially increased in a longitudinal direction, the blood reservoir part being disposed at a position away from the first region ,
a valve support member that sandwiches the disk valve between the outer needle hub and the valve support member and positions the disk valve relative to the outer needle hub, the valve support member being fixedly disposed in the inner cavity of the outer needle hub;
The indwelling needle with a hemostatic valve, wherein the air passage is formed between the inner surface of the outer needle hub and the outer surface of the disk valve and the outer surface of the valve support member . The indwelling needle with hemostatic valve according to claim 1, wherein a narrowed section having a smaller cross-sectional area than the blood reservoir section is provided on the proximal side of the blood reservoir section in the air passage. In an indwelling needle with a hemostatic valve, a cylindrical outer needle hub is provided on the base end side of a hollow outer needle, and a disk valve is disposed on the outer needle hub,
the disk valve has a fitting portion that is pressed against the inner circumferential surface of the outer needle hub and compressed in the radial direction, and a spaced portion that faces away from the inner circumferential surface of the outer needle hub,
a minute passage extending between the overlapping surfaces of the outer peripheral surface of the fitting portion of the disk valve and the inner peripheral surface of the outer needle hub is partially formed in the circumferential direction, and a minute gap is formed over the entire circumference between the separation portion and the outer needle hub, and the minute passage and the minute gap are mutually communicated,
an air passage that communicates a first region on the distal end side of the disk valve in the inner cavity of the outer needle hub with a second region on the proximal end side of the disk valve is configured to include the minute passage and the minute gap ,
a valve support member that sandwiches the disk valve between the outer needle hub and the valve support member and positions the disk valve relative to the outer needle hub, the valve support member being fixedly disposed in the inner cavity of the outer needle hub;
The indwelling needle with a hemostatic valve, wherein the air passage is formed between the inner surface of the outer needle hub and the outer surface of the disk valve and the outer surface of the valve support member . 4. The indwelling needle with a hemostatic valve as described in claim 3, wherein the fitting portion of the disk valve has a larger diameter than the separating portion, a fine groove is formed opening onto the outer peripheral surface of the fitting portion, and the outer peripheral opening of the fine groove is covered by the outer needle hub to form the micropassage.

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