Catheter components

Abstract

The present invention provides a catheter assembly, comprising: a catheter hub having a chamber therein, the catheter hub having a distal end and a proximal end, the catheter hub at its proximal end being connectable to a device for infusing fluid into the chamber in the catheter hub or extracting fluid from the chamber; a hollow tubular catheter having a proximal end and a distal end, the catheter being connected at its proximal end to the distal end of the catheter hub, the interior of the catheter leading to the chamber in the catheter hub; a needle having a sharp needle tip, in a prepared position, the needle extending through the chamber and the catheter in the catheter hub and the needle tip extending beyond the distal end of the catheter; a hollow extension tube having a distal end and a proximal end, the extension tube being connected at its distal end between the proximal end and the distal end of the catheter hub, the extension tube leading to the chamber in the catheter hub at its distal end, the extension tube being connectable at its proximal end to a device for infusing fluid into the chamber in the catheter hub; a valve assembly disposed in the chamber of the catheter hub, the valve assembly comprising a first valve component and a second valve component. The present invention also provides a needle sheath assembly.

Description

[0001] This application is a divisional application of the Chinese patent application entitled “Catheter Assembly” and having application number 201310527778.3 filed on October 31, 2013. Technical Field

[0002] The present invention relates to a catheter assembly, in particular to a intravenous catheter assembly. Background Art

[0003] An intravenous (IV) catheter is used to access a patient's vein, particularly for the purpose of providing fluids to or removing fluids (particularly blood) from the patient. Prior to puncturing the patient, the IV catheter may be filled with a sterile solution to remove air from the device. This may reduce the risk of air embolism in the patient.

[0004] The intravenous catheter assembly includes a catheter extending from the distal end of a catheter hub. A needle extends through the catheter hub and the catheter so that the sharp needle tip of the needle extends beyond the distal end of the catheter. The typical steps for inserting a catheter into a patient's vein require a medical professional to insert the sharp needle tip and catheter into the patient in order to position it in the vein. Once the needle tip is in the vein, the medical professional manually pushes the catheter into the vein by sliding the catheter along the needle shaft in a distal direction. Once the catheter is properly positioned in the vein, the needle is removed. The catheter is then secured by taping the catheter hub to the patient's skin. The vein can then be accessed to infuse or remove fluids through the catheter hub and catheter.

[0005] In order to control the flow of fluid through the catheter and the catheter hub, and in particular to prevent blood from leaving the vein through the catheter, it is known to provide a valve in the catheter hub.

[0006] A device for withdrawing fluid from or infusing fluid into a patient is disclosed in EP 2268480. In one embodiment, the device includes a catheter hub having a catheter extending from the catheter hub. The catheter hub is provided with a flexible valve for controlling the flow of fluid through the catheter hub. A valve opener is provided for opening the valve when it is desired to infuse or withdraw fluid through the proximal end of the catheter hub. EP2268480 discloses a catheter hub provided with a port extending laterally from the catheter hub. A flexible cylindrical seal consistent with the port extends circumferentially within the interior of the catheter hub.

[0007] US 5,098,405 relates to a side port type catheter hub with a one-piece integral combination valve. The valve is disposed in the hub of the adapter to close the aperture and the side port of the adapter. The valve assembly includes a generally cylindrical body extending circumferentially inside the hub in accordance with the port. The valve assembly also includes a conical valve element to allow fluid to flow from the proximal end of the hub into the catheter. The device of US 5,098,405 does not allow fluid to be removed from the patient but only allows fluid to be infused into the patient through the proximal end of the adapter hub or port.

[0008] A medical connector is described and illustrated in WO 96 / 40359. The connector comprises a body having a main conduit and a port therethrough. A generally cylindrical valve is located within the body, in line with the port. A tab extends from the valve into the port. The valve is normally open, allowing fluid to flow along the main conduit. The valve in the main conduit is closed by pressing the tab in the port, thereby preventing the flow of fluid along the valve and allowing fluid to be infused into the connector or withdrawn from the connector through the port.

[0009] More significantly, a catheter device with an infusion port and a valve is disclosed in WO 2008 / 052791. The catheter device includes a hollow catheter connector, the distal end of which can be connected to a catheter. A connecting device is provided at the proximal end of the catheter connector. A port extends radially from the catheter connector and leads to a hole of the connector. A valve assembly is provided in the connector and is consistent with the port, and includes a first valve element of a generally cylindrical shape for closing the port. A second valve element prevents blood from flowing out of the connector through the hole in a proximal direction. The second valve element is configured as a two-way valve, thereby allowing fluid to flow in a distal direction or a proximal direction.

[0010] Recently, WO 2008 / 052790 discloses a catheter assembly and its components. The assembly includes a valve and a valve opener disposed in a catheter hub. The valve opener is configured to be pushed by a Luer connector of an IV set to open the valve, thereby allowing fluid to pass through the catheter. A needle tip protector operable to cover the needle tip when the needle is withdrawn from the catheter through the catheter hub may be disposed within the valve opener.

[0011] Perhaps more recently, WO 2012 / 009028 discloses a flushable catheter assembly. The assembly includes a catheter hub having a septum. A septum actuator is provided for selectively opening the septum and allowing fluid to flow through the catheter hub when a connector is attached to the proximal end of a catheter adapter.

[0012] There is a need for an improved catheter assembly, particularly a need for a catheter assembly that provides enhanced control over the infusion and withdrawal of fluids into and from a patient through a catheter. Summary of the invention

[0013] According to the present invention, there is provided a catheter assembly, the catheter assembly comprising:

[0014] a catheter hub having a chamber therein, the catheter hub having a distal end and a proximal end, the catheter hub being connectable at its proximal end to a device for infusing or withdrawing fluid into or from the chamber in the catheter hub;

[0015] a hollow tubular catheter having a proximal end and a distal end, the catheter being connected at its proximal end to the distal end of the catheter hub, the interior of the catheter opening into a chamber within the catheter hub;

[0016] a needle having a sharpened needle tip, the needle extending through the chamber in the catheter hub and the catheter in the prepared position and the needle tip extending beyond the distal end of the catheter;

[0017] a hollow extension tube having a distal end and a proximal end, the extension tube being connected at its distal end to the catheter hub between the proximal and distal ends, the extension tube opening at its distal end to a chamber within the catheter hub, the extension tube being connectable at its proximal end to a device for infusing a fluid into the chamber within the catheter hub;

[0018] A valve assembly disposed in a chamber of a catheter hub, the valve assembly comprising:

[0019] a first valve component that closes the distal end of the extension tube and is capable of opening in response to pressurized fluid within the extension tube; and

[0020] A second valve component prevents fluid from flowing through the chamber to or from the proximal end of the catheter hub, the second valve component being a two-way valve and openable to allow fluid to flow through the chamber in the catheter hub in both a proximal and a distal direction.

[0021] The device of the present invention includes a catheter hub. The catheter hub is hollow and has an interior chamber that is open at the proximal and distal ends of the catheter hub. The catheter hub can be constructed as a single piece. Alternatively, the catheter hub can be constructed as two or more separate parts connected together.

[0022] The catheter hub is formed to be connectable at its proximal end to a device (e.g., a syringe) for infusing or removing fluid from a patient. Such devices are known in the art and will be familiar to those skilled in the art. In particular, the inner wall of the proximal end of the catheter hub defining the chamber is provided with an internal Luer taper, i.e., a female Luer taper, allowing a standard connector having a standard male Luer taper to be connected to the proximal end of the catheter hub. Those skilled in the art will be familiar with standard Luer tapers and their requirements.

[0023] In one embodiment, the catheter hub includes a distal hub portion and a proximal hub portion. The proximal hub portion is as described above and is capable of being connected to a device for infusing fluid into a patient or removing fluid from a patient. The distal hub portion may have any suitable shape. In one embodiment, the distal hub portion has a generally flat shape so that the catheter hub rests more flatly against the patient's skin and protrudes less from the patient's skin during use. More preferably, the distal hub portion includes a wing member extending from opposite sides of the distal hub portion. The wing member increases the stability of the catheter assembly, particularly when the catheter has been inserted into the patient's vein, and can be used to secure the catheter hub to the patient's skin, such as by tape. In this way, the movement of the catheter hub and the catheter is limited, thereby correspondingly reducing the incidence of phlebitis in the patient's vein.

[0024] A hollow tubular catheter is connected to the catheter hub and extends from a distal end of the catheter hub.

[0025] The catheter assembly also includes a needle having a sharp needle tip and a hole through the needle. In the ready position, the needle is connected to the needle hub at its proximal end, as is known in the art, and extends through the catheter hub and catheter in the ready position. In the ready position, the sharp needle tip is the distal end of the catheter, thereby allowing the needle and catheter to be introduced into the patient's vein in a known manner. The needle hub preferably has a chamber that communicates with the hole in the needle shaft, whereby the user can observe blood flashback in the needle hub chamber indicating in a known manner that the needle has been accurately placed in the vein. The needle hub chamber is usually plugged at its proximal end with a vent plug that allows air to be vented from the chamber but does not allow blood to flow through the plug.

[0026] When the needle tip is withdrawn into a hollow tubular catheter, secondary blood flashback occurs between the outside of the needle and the inside of the catheter.

[0027] The conditions for primary and secondary blood return are that the air in the catheter device can be replaced by blood when the air is exhausted from the proximal end of the device.

[0028] In one embodiment, the needle is provided with an opening (e.g., a slot) in the needle shaft at a distal portion of the needle away from the sharp needle tip. In the ready position, the slot is disposed within the tubular catheter. In use, once the needle tip has been inserted into a vein, blood can flow along the hole in the needle, through the slot, and into the catheter surrounding the needle shaft. The blood can then flow from the catheter into the catheter hub to provide blood flashback to the user.

[0029] The catheter assembly of the present invention also includes a hollow extension tube having a distal end and a proximal end. The extension tube is flexible. The extension tube is connected at its distal end to a catheter hub between its proximal end and its distal end. Preferably, the distal end of the extension tube is connected to the distal portion of the catheter hub. The extension tube leads to a chamber of the catheter hub at its distal end, thereby allowing fluid to flow between the extension tube and the inner chamber. The extension tube can be connected at its proximal end to a device (such as a syringe) for infusing fluid into the chamber in the catheter hub. For example, the extension tube may be provided with a connecting hub at its proximal end, preferably a hub with a female Luer cone connector.

[0030] In use, fluid can be introduced into the catheter hub and catheter via the extension tube. By connecting the device for introducing fluid to the proximal end of the extension tube, the device can be located away from the catheter hub and catheter located in the patient's vein. By making the extension tube flexible, the movement of the catheter hub and catheter caused by the operation of connecting or disconnecting the fluid delivery device at the proximal end of the extension tube is reduced or eliminated. This correspondingly reduces the incidence of phlebitis in the catheter area.

[0031] The catheter assembly includes a valve assembly disposed in an inner chamber of a catheter hub. When closed, the valve assembly prevents the flow of fluid between the extension tube and the inner chamber of the catheter hub, and the flow of fluid in the proximal direction or through the inner chamber in the proximal direction. The valve assembly includes a first valve component, which can allow the fluid to flow from the extension tube to the inner chamber of the catheter hub by opening the first valve component. In this regard, the valve assembly can be a one-way valve between the extension tube and the inner chamber of the catheter hub. The valve assembly includes a second valve component, which can also allow the fluid to be provided to the catheter in the proximal direction from the proximal end of the catheter hub or allow the fluid to be withdrawn from the catheter in the proximal direction to the proximal end of the catheter hub by opening the second valve component. In this way, the valve assembly acts as a two-way valve, which is used to control the flow of fluid through the catheter hub to its proximal end and the flow from its proximal end.

[0032] The first valve member controls the flow of fluid between the extension tube and the inner chamber of the catheter hub. In a preferred embodiment, the first valve member includes a flexible elastic valve body. Under the action of increased fluid pressure in the extension tube, the valve body bends, thereby opening the distal end of the extension tube and allowing fluid to enter the catheter hub. The valve body is preferably a tubular body, specifically disposed in the inner chamber of the catheter hub and in contact with the inner surface of the catheter hub wall. The cross-section of the valve body and the portion of the catheter hub inner chamber where the valve body is disposed can be cylindrical or, in one embodiment, elliptical.

[0033] The first valve member may include one or more slits that are aligned with the distal opening of the extension tube and are used to allow fluid to pass therethrough. If the first valve member has one or more slits, it can function as a two-way valve and blood or other body fluids can be removed through the slits and the extension tube leading to a suitable device (e.g., a syringe or a vacuum blood collection tube).

[0034] The valve assembly includes a second valve component. As described above, the second valve component controls the flow of fluid through the inner chamber of the catheter hub to its proximal end and the outflow of fluid from its proximal end. The second valve component is arranged in the inner chamber of the catheter hub at a distal opening of the extension tube and a proximal position of the first valve component. In one embodiment, the second valve component includes a flexible elastic valve disc, which extends laterally across the inner chamber of the catheter hub. The valve disc is provided with one or more closable openings (e.g., slits), in particular one or more radially extending slits.

[0035] The valve assembly may be retained in the interior chamber of the catheter hub by any suitable means. In one embodiment, the valve assembly is retained by friction between the valve components and the interior surface of the catheter hub. Alternatively, the valve assembly may engage with one or more grooves or protrusions formed in the interior surface of the catheter hub.

[0036] In the ready position, the needle rod extends through the valve assembly. The second valve member preferably seals around the needle rod in the ready position, more preferably in a manner that allows gas to be discharged in a proximal direction through the second valve member but prevents blood from passing through the second valve member. In embodiments where the second valve member comprises a valve disc having one or more slits, this can be achieved by appropriately arranging the slits so that in the ready position the slits are held open by the needle rod by an amount sufficient to allow gas to pass but prevent blood from passing.

[0037] The second valve member can be opened in response to a fluid pressure differential before and after the valve member. In particular, the second valve member can be opened in response to an increased fluid pressure acting on the proximal side of the valve, thereby allowing fluid to be infused into the catheter and the patient's vein. Similarly, the second valve member can be opened in response to a reduced pressure acting on the proximal side of the valve, thereby allowing fluid to be withdrawn from the catheter and the vein.

[0038] In one embodiment, the catheter assembly further comprises a valve opener disposed in a chamber within the catheter hub. The valve opener is disposed in an inner chamber of the catheter hub proximal to the valve assembly. The valve opener is movable between a closed position in which the second valve component is closed and an open position in which the second valve component is opened. The valve opener is moved in a proximal direction to an open position by inserting a device (e.g., a syringe or other male connector) into the proximal end of the catheter hub. The valve opener is pushed to a closed position by the operation of closing the second valve component (e.g., utilizing the elasticity of a valve disc). The valve opener preferably has a passage extending longitudinally therethrough or in the vicinity thereof for passage of fluid.

[0039] The valve assembly limits movement of the valve opener in a proximal direction. Preferably, means for limiting movement of the valve opener in a proximal direction are provided. In one embodiment, the inner surface of the catheter hub is provided with one or more protrusions that engage with the valve opener.

[0040] In the ready position, the needle rod extends through the valve opener. A preferred form of the valve opener includes: a handle having a channel, and a head located at the distal end of the handle and having the channel. In use, a device inserted into the proximal end of the catheter hub contacts the handle of the valve opener, thereby pushing the valve opener from the closed position to the open position. When the valve opener is moved in the proximal direction to the open position, the head is pushed to contact the second valve component, thereby opening the valve assembly.

[0041] The handle may comprise a tube through which the needle extends in the ready position. Alternatively, the handle may comprise one or more legs extending from the head in a proximal direction. In one embodiment, the region of the head in contact with the second valve member is generally dome-shaped or frusto-conical.

[0042] In a preferred embodiment, the catheter device of the present invention is a safety device and includes a needle shield assembly. The function of the needle shield assembly is to cover and block the sharp needle tip when the needle is withdrawn from the catheter in the proximal direction and moved from the ready position to the protected position. In this way, the risk of needle stick injuries can be reduced or avoided.

[0043] The needle shield assembly may be arranged completely or partially in the inner chamber of the catheter hub. In particular, the needle shield may be arranged in the catheter hub so that the needle is in its protected position and the needle shield assembly blocks the sharp needle tip while the needle tip is in the catheter hub. An example of a preferred needle shield assembly for such an embodiment is disclosed in WO 99 / 08742. The needle shield of WO 99 / 08742 is of a passive type, i.e. the needle shield blocks the needle tip when the needle is withdrawn from the ready position to the protected position without the user having to perform any other operations required in the use of a standard device or a non-safety device. This type of passive needle shield is preferred.

[0044] Alternatively, the needle shield assembly may be disposed outside the catheter hub, particularly at the proximal end of the catheter hub. In a preferred embodiment, the needle shield assembly comprises a needle shield housing having a needle shield chamber. Preferably, the needle shield is disposed in the chamber. The needle shield housing may have a portion extending into the proximal end of the catheter hub. For example, the needle shield housing may have a distal portion comprising a male conical connector (e.g., a standard Luer conical connector) that is adapted to engage a female conical connector located at the proximal end of the catheter hub. Alternatively, the needle shield housing is entirely present outside the catheter hub.

[0045] Preferably, the needle shield assembly is releasably engaged with the catheter hub. In a preferred embodiment, the needle shield assembly engages with the catheter hub when the needle is in the ready position. The needle shield assembly is released from the catheter hub by moving the needle to a protective position blocking the needle tip.

[0046] Most preferably, in the protected position, the needle tip is disposed within the needle shield housing and the needle shield blocks the needle tip within the housing.

[0047] The needle shield is arranged in the needle shield housing. The needle shield of WO 99 / 08742 can be applied in the needle shield housing.

[0048] In a preferred embodiment, the needle shield in the housing includes a needle trap that can move between a ready position and a protected position, in which the needle trap is held to one side of the needle shaft extending through the housing, and in which the needle trap extends across the needle tip and blocks the sharp needle tip of the needle within the housing. The needle shield also includes an elastic arm that biases the needle trap to the protected position. The elastic arm is supported on the inner wall of the housing and is used to push the needle to the protected position. In addition, the needle shield includes a connecting arm that can be moved using the needle trap. In the ready position, the connecting arm connects the housing to the proximal end of the catheter hub. The movement of the needle trap from the ready position to the protected position causes the connecting arm to move to release the housing from the catheter hub.

[0049] Therefore, in another aspect, the present invention provides a needle shield assembly for a catheter assembly, the needle shield assembly comprising:

[0050] a housing for receiving a needle extending therethrough and having a distal end and a proximal end, the housing being connectable at its distal end to the proximal end of the catheter hub;

[0051] A needle shield disposed in the housing, the needle shield comprising:

[0052] a needle trap movable between a ready position in which the needle trap is held to one side of a needle shaft extending through the housing and a protected position in which the needle trap blocks the sharp tip of the needle within the housing;

[0053] an elastic arm biasing the needle trap to the protection position, the elastic arm being supported on the inner wall of the housing for pushing the needle trap to the protection position;

[0054] A coupling arm couples the housing to the proximal end of the catheter hub in the prepared position, and movement of the needle trap from the prepared position to the protected position moves the coupling arm to release the housing from the catheter hub.

[0055] The needle trap may be connected to one end of the elastic arm. In a preferred embodiment, the needle trap may be pivotally attached to the elastic arm at its first end. The elasticity of the elastic arm may be provided partially or completely by utilizing the elasticity in the pivotal connection between the needle trap and the elastic arm. In one embodiment, the needle trap and the elastic arm are folded together on one side of the needle rod when in the ready position so that the needle trap is supported on the elastic arm.

[0056] In the protection position, the needle trap extends distally across the sharp needle tip, thereby blocking the needle tip and preventing needle stick injuries. The needle trap may include one or more lateral components extending from each side of the needle trap in the proximal direction. The function of the lateral components is to fix the needle trap relative to the sharp needle tip, in particular to prevent the needle tip from being exposed on one side of the needle trap. In use, the needle trap is converted from the ready position through the needle tip into the protection position. In addition, the needle trap may include a retaining component that prevents the needle trap from moving in the opposite direction (i.e., in the direction toward its ready position) relative to the needle.

[0057] The needle shield also includes a coupling arm. In the ready position, the coupling arm engages with the catheter hub, thereby keeping the needle shield assembly at the proximal end of the catheter hub. In a preferred embodiment, the coupling arm engages with the outside of the catheter hub, for example, with a flange on the proximal end of the catheter hub. The coupling arm is moved by making the needle trap from the ready position into a protection position that is not engaged with the catheter hub, thereby releasing the needle shield assembly from the catheter hub. In this way, once the sharp needle tip is blocked in the needle shield housing, the needle shield assembly is only released from the state engaged with the catheter hub. The coupling arm is preferably connected to the needle trap. In a preferred embodiment, the coupling arm is connected to one end of the needle trap, specifically connected to the second end of the needle trap opposite to the first end. The connection between the coupling arm and the needle trap is preferably a pivot connection and can be an elastic pivot connection.

[0058] In a preferred embodiment, the resilient arm, needle trap and coupling arm constitute a single component, and resilient pivot connections are provided between the resilient arm and the needle trap and between the needle trap and the coupling arm, the resilient connection biasing the needle trap to a protective position and preventing the coupling arm from engaging the catheter hub.

[0059] The position of the needle trap is preferably stabilized by engaging the coupling arm with the wall of the needle shield housing on one side of the needle shaft and engaging the resilient arm with the wall of the needle shield housing on the opposite side of the needle shaft. In a preferred embodiment, the coupling arm extends through an opening in the wall of the needle shield housing.

[0060] In one embodiment, in the ready position the coupling arm extends around the needle shaft, preferably within the needle shield housing. In a preferred embodiment, the coupling arm comprises an opening, and in the ready position the needle shaft extends through this opening in the coupling arm.

[0061] In the protection position, the needle trap extends distally across the sharp needle tip and prevents the needle from moving in the proximal direction relative to the needle shield assembly. The needle shield assembly also includes a device for limiting the movement of the needle in the proximal direction relative to the needle shield assembly, thereby preventing the needle shield assembly from leaving the distal end of the needle. The limiting device may include a tether, such as a tether extending between the needle hub and the needle shield housing. Preferably, the needle includes a protuberance such as a fold at the distal end portion of the needle shaft away from the needle tip. The needle shield assembly, preferably the needle shield housing, includes a proximal wall with an opening, and the needle shaft extends through the opening in the proximal wall. The radial dimension of the protuberance in the needle shaft is greater than the radial dimension of the opening in the proximal wall, so that the protuberance and the distal end of the needle cannot pass through the opening. For example, a metal ring or a gasket can be used to strengthen the proximal wall area located around the opening to prevent the protuberance in the needle shaft from being accidentally pulled out through the proximal wall of the housing. This is particularly advantageous when the needle shield housing is composed of a relatively soft material (e.g., plastic). In the ready position, the bulge in the needle shaft is preferably located within the hollow catheter. When the bulge is non-circular, the bulge has the advantage of allowing blood to flow between the inside of the catheter and the outside of the needle, thereby providing secondary blood flashback.

[0062] In another aspect, the present invention provides an intravenous catheter assembly comprising a needle guard assembly as hereinbefore described. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Embodiments of the present invention will now be described with reference only to the accompanying drawings, in which:

[0064] Figure 1 is a cross-sectional view of a device according to a first embodiment of the present invention in a ready position;

[0065] Figure 2 It is in direction II Figure 1 A cross-sectional view of a device;

[0066] Figure 3 is in the retracted position Figure 1 A cross-sectional view of a device;

[0067] Figure 4 is a cross-sectional view of a device according to a second embodiment of the present invention in a ready position;

[0068] Figure 4a yes Figure 4 An enlarged cross-sectional view of a needle shield assembly of the device;

[0069] Figure 5 It is in a protected position Figure 4 A cross-sectional view of a device;

[0070] Figure 5a yes Figure 5 An enlarged cross-sectional view of a needle shield assembly of the device;

[0071] Figure 6 is a cross-sectional view of a device according to a third embodiment of the present invention in a ready position;

[0072] Figure 7a is used for Figures 1 to 6 a cross-sectional view of a valve assembly of any device;

[0073] Figure 7b yes Figure 7a A proximal end view of one embodiment of a valve assembly;

[0074] Figure 7c yes Figure 7a A proximal end view of a second embodiment of a valve assembly;

[0075] Figure 8 is a perspective view of one embodiment of a needle guard for use with the catheter assembly of the present invention. DETAILED DESCRIPTION

[0076] Reference Figure 1 and Figure 2 , there is shown an apparatus generally indicated at 2 according to a first embodiment of the present invention. Figure 1 and Figure 2 In the display device 2 is in the ready position. Figure 3 The device is shown in the retracted position, ie the needle is withdrawn in the proximal direction.

[0077] The device 2 includes a catheter hub 4 having a distal end 6 and a proximal end 8. An elongated hollow tubular catheter 10 is connected to the catheter hub 4 in a known manner and extends from the distal end 6 of the catheter hub. The catheter hub 4 includes an internal chamber 12. The internal chamber 12 is open at the proximal end 8 of the catheter hub 4 and communicates with the hollow catheter 10 at the distal end of the catheter hub. The details of the catheter hub are described in more detail below.

[0078] The generally cylindrical needle hub 20 has a distal end 22 and a proximal end 24. The needle hub 20 is formed with an internal chamber 26, the open proximal end of which is closed by a vented flashback plug 28. In use, again in a known manner, the chamber 22 in the needle hub 20 functions as a flashback chamber to facilitate observation of flashback by the user.

[0079] The needle 30 is connected at its proximal end 32 to the distal end 22 of the needle hub 20. The needle 30 has a shaft 34 having a hole therethrough and a sharp needle tip 36 at its distal end. In the ready position, Figure 1 and Figure 2 As shown in FIG. 4 , the needle 30 extends through the interior chamber 12 of the catheter hub 4 and through the catheter 10 such that the sharp needle tip 36 extends beyond the distal end of the catheter 10 .

[0080] The needle 30 may be provided with a groove 38 at the distal end portion of the needle, and the groove 38 is spaced from the sharp needle tip 36. In the ready position, the groove 38 is located within the catheter 10. In use, blood entering the hole in the needle shaft 34 flows out through the groove 38 and flows between the needle shaft 34 and the inner surface of the catheter 10 and provides a flashback indication to the user to indicate that the needle tip is properly located in the patient's vein. The blood flowing through the hole in the needle shaft 34 enters the interior chamber 26 of the needle hub 20 and provides a flashback indication to the user, as described above.

[0081] As described above, the device 2 includes a catheter hub 4 having an interior chamber 12. The catheter hub 4 has a proximal portion 40 and a distal portion 42. The interior chamber 12 is open at the proximal end 8 of the catheter hub 4 and extends through the proximal portion 40 and the distal portion 42 of the catheter hub 4, thereby communicating with the hollow catheter 10. The proximal portion 40 of the catheter hub 4 is generally conical in structure and is provided with an internal conical connector 44, in particular a female Luer cone connector of a standard shape. The proximal portion 40 of the catheter hub 4 is provided with a protrusion 46, which extends into the interior chamber 12 and is located distal to the Luer cone connector. Figure 1 and Figure 2 In the embodiment shown in FIG. 4 , the protrusion 46 is in the form of a circumferentially extending ring.

[0082] The valve opener 50 is disposed in the proximal portion 40 of the catheter hub 4. The valve opener 50 has an elongated shaft 52 and a conical head 54 disposed at the distal end of the shaft 52. A bore extends longitudinally through the valve opener 50 and receives the shaft of the needle 30 in a ready position, such as Figure 1 and Figure 2 The valve opener 50 is held in the inner chamber 12 of the catheter hub 4, and the movement of the valve opener 50 in the proximal direction is limited by the protrusion 46. Under the action of a male connector (such as a syringe) inserted into the proximal end 8 of the catheter hub 4, the valve opener 50 can move freely in the distal direction.

[0083] The distal portion 42 of the catheter hub 4 has a generally straight profile, such as Figure 2 and Figure 3 As shown in FIG, fin members 60 extend from opposite sides of the catheter hub 4. The fin members 60 provide a means for securing the catheter hub 4 to the patient's skin, such as by a suitable medical grade tape.

[0084] exist Figures 1 to 3 In the arrangement shown in FIG. 4 , the proximal portion 40 and the distal portion 42 of the catheter hub 4 may be constructed as a single component or they may be connected together after being formed separately.

[0085] A flexible extension tube 62 extends from the distal portion 42 of the catheter hub 4. The distal end of the extension tube 62 leads to the inner chamber 12 of the catheter hub. The proximal end of the extension tube 62 is provided with a hollow connection hub 64, which has a proximal opening and is provided with an internal conical connector for receiving a connector (such as a syringe, etc.) in a known manner, in particular a standard female Luer conical connector. In order to maintain sterility, a vent plug 66 can be provided at the proximal end of the connection hub 64, such as Figure 1 The connecting hub 64 can be used to introduce fluid into the extension tube 62 and the catheter assembly 2, for example, using Figure 3 The syringe 68 is shown in FIG.

[0086] The distal portion 42 of the catheter hub 4 is also provided with a valve assembly 70. The valve assembly 70 is provided in the inner chamber 12 of the catheter hub and includes a second valve portion 72 provided in the inner chamber 12 distal to the valve opener and a first valve portion 74 distal to the second valve portion.

[0087] The function of the second valve portion 72 is to seal the inner chamber 12 in the catheter hub 4 so as to prevent the flow of fluid in the proximal direction or the distal direction when the second valve portion is closed. The second valve portion 72 includes a flexible valve disc 76 that extends laterally across the inner chamber 12 of the catheter hub 4. The valve disc 76 is made of a flexible elastic material. The valve disc 76 has one or more radial slits therein. Thus, in the ready position, the shaft 34 of the needle 30 extends through the valve disc 76, as shown in FIG. Figure 1 and Figure 2 as shown in . Figures 7a to 7c Details of an embodiment of a valve assembly are shown in FIG. 1 and described below.

[0088] When the needle is in the ready position, the valve disc 76 is closed around the outer surface of the needle shaft 34. When the needle 30 is in the ready position, the slit is kept open a distance sufficient to allow air to escape through the valve disc in the proximal direction, while being sufficiently closed to prevent blood from flowing in the proximal direction through the valve disc 5. By allowing air to escape through the valve disc 76 in this manner, blood can flow from the groove 38 in the needle shaft 34 along the outside of the needle within the catheter 10 when the needle tip is withdrawn into the hollow catheter, or in the absence of the groove 38 in the needle, thereby providing secondary blood flashback.

[0089] The second valve portion 72 is a two-way valve. When the needle 30 is retracted and the valve disc 76 is closed, fluid is prevented from flowing in the catheter hub 4 in either the distal or proximal direction. When the valve opener 50 is absent, the valve disc 76 is opened proximally of the valve disc 76 under reduced fluid pressure, such as by applying a vacuum to the proximal end of the catheter hub 4 with a syringe engaged with the proximal end of the catheter hub 4. In this way, fluid can be withdrawn from the catheter 10 through the catheter hub in the proximal direction to the proximal end 8 of the catheter hub 4. The valve is opened and fluid is allowed to flow through the catheter hub in the distal direction by applying increased fluid pressure proximally of the valve disc 76 (e.g., by a syringe engaged with the proximal end of the catheter hub 4). In this way, fluid can be infused into the patient through the catheter hub 4 and the catheter 10.

[0090] The valve opener 50 is pushed in the distal direction by engaging the connector with the proximal end 8 of the catheter hub 4 (e.g., a syringe with a male conical connector, particularly a standard male Luer conical connector, etc.). Movement of the valve opener 50 in the distal direction causes the head 54 of the valve opener to contact the valve disc 76 and open the gap in the valve disc, and fluid can be withdrawn from the patient or infused into the patient when the valve is opened in the above manner. The valve disc 76 is formed of an elastic material. When the male connector is removed and not engaged with the proximal end 8 of the catheter hub 4, the valve disc 76 pushes the opener 50 in the proximal direction until the gap in the valve disc is closed. As described above, the protrusion 46 in the proximal portion of the catheter hub 4 prevents the valve opener 50 from moving further in the proximal direction.

[0091] The first valve portion 74 is disposed in the inner chamber 12 of the catheter hub 4, distal to the second valve portion 72. The function of the first valve portion 74 is to seal the opening in the distal end of the extension tube 62. The first valve portion 74 is in the form of a tube 80 of a flexible, elastomeric material that extends around the circumference of the inner chamber 12 of the catheter hub 4. The tube 80 conforms to the inner surface 15 of the distal portion 42 of the catheter hub and provides a fluid-tight seal against the inner surface. The inner chamber 12 in the distal portion 42 of the catheter hub 4 can be generally cylindrical, in which case the tube 80 is generally cylindrical. Alternatively, the cross-section of the inner chamber 12 in the distal portion 42 of the catheter hub 4 can be elliptical. The cross-section of the tube 60 of this arrangement is also elliptical. Figures 7a to 7c An embodiment of a valve assembly is shown in FIG. 1 and described in more detail below.

[0092] As described above, the tube 80 seals the distal end of the extension tube 62 at its opening to the interior chamber 12 in the catheter hub 4. The interference fit between the tube 80 and the catheter hub 4 forces the outer surface of the tube 80 to contact the inner surface of the distal portion 42 of the catheter hub, thereby forming a fluid-tight seal. The increased fluid pressure within the extension tube 62 pushes a portion of the tube 80 away from the inner surface 30 of the interior chamber 12, thereby allowing fluid to flow from the extension tube 62 into the interior chamber 12 and in a distal direction to the catheter 10. In this way, the extension tube 62 can be used to introduce fluid into the catheter 10, for example, from a syringe 68 connected to the connecting hub 64, such as Figure 3 as shown in .

[0093] To ensure distal infusion toward the hollow catheter, the proximal end of the tube 80 may be further reinforced by inserting a hard ring at the proximal end of the tube 80 just distal to the valve disc 76, or a flange may extend from the disc 76 held in a groove in the inner surface of the catheter hub.

[0094] Steering Figure 4 and Figure 5 , an alternative embodiment of the device of the present invention is shown in the figure. The device of this embodiment, generally indicated as 102, includes: a catheter hub, a catheter, a needle hub and a needle, a valve assembly and a valve opener, and a Figure 1 and Figure 2 And an extension tube of the same general construction as the above-described embodiment. Figure 3 and Figure 4 Embodiments of the invention Figure 1 and Figure 2 Identical features of the embodiments are denoted by the same reference numerals.

[0095] Figure 3 and Figure 4 Embodiments include a needle shield assembly disposed between the distal end of the needle hub 20 and the proximal end of the catheter hub 4 when the device is in the ready position, such as Figure 3 As shown in Figure 4a , the needle shield assembly, generally designated 120, is shown in more detail in the ready position.

[0096] There may be some degree of overlap of the needle shield proximal end with the needle hub distal end and / or some degree of overlap of the needle shield distal end with the catheter hub proximal end.

[0097] Reference Figure 4a , the needle shield assembly 102 includes a generally cylindrical needle shield housing 122 having a proximal end 124 and a distal end 126. Alternative shapes of the needle shield housing include a generally rectangular cross-section. The distal end is tapered and is provided with a standard conical connector, particularly a standard male Luer conical connector. Figure 3In the prepared position shown in FIG. 4 , the conical distal end 126 of the needle guard housing 122 extends within the female Luer taper connector in the proximal end 8 of the catheter hub 4 .

[0098] The needle shield housing 122 includes an interior chamber 128 that is open at the distal end 126 and is closed at the proximal end 124 by a proximal wall 130. In the ready position, the needle shaft 34 extends through the interior chamber 128 and the proximal wall 130 of the needle shield housing 122, as shown in FIG. Figure 4 and Figure 4a as shown in .

[0099] The needle guard 140 is disposed within the needle guard housing 122 and includes a needle well 142 having a lateral member or side member 144 extending in a proximal direction from the needle well 142. The needle well also includes a retaining member 146. When the needle 30 is retracted Figure 5 When in the protected position shown in FIG. 1 , the side members 144 and the retaining member 146 prevent lateral movement of the needle well 142 relative to the needle and prevent exposure of the needle tip.

[0100] The needle guard 140 also includes a resilient arm 150 that is pivotally connected to the needle well at a first end 152 and supported on an inner surface of the needle guard housing 122 at a second end.

[0101] The needle shield 140 further comprises a coupling arm 160 which is pivotally connected at a first end to the needle well 142 at a position opposite to the connection between the needle well and the resilient arm 150. The coupling arm 160 extends from the needle well 142 across the interior chamber 128 and through an opening 162 in the needle shield housing 122. The coupling arm 160 is provided with a hook 164 at its free end located outside the needle shield housing 122, which engages with a flange 166 on the exterior of the proximal end 8 of the catheter hub 4, as shown in FIG. Figure 4 An opening 168 is provided in the coupling arm 150, through which the needle rod 34 extends in the ready position. Figure 4a as shown in .

[0102] exist Figure 4 and Figure 4a In the ready position shown in FIG, in the folded position superimposed on the elastic arm 150, the needle trap 142 is held to one side of the needle shaft 34. The coupling arm 160 is held by the needle shaft 34 retracted in the needle shield housing 122, thereby holding the hook 164 in a state of engagement with the flange 166 on the proximal end 8 of the catheter hub 4.

[0103] The inherent elasticity of the needle shield 140 pushes the needle shield to a straight orientation. In the ready position, the needle rod 34 resists the inherent bias of the needle shield and holds the needle well 142. When the needle 30 is retracted Figure 5 and Figure 5a, particularly when the needle tip 36 is moved to a position within the needle shield housing 122 proximal to the needle well and the coupling arm, the resiliency of the needle shield 140 pushes the needle well 142 to a blocking position across the needle tip 36. The same movement pushes the hook 164 of the coupling arm out of engagement with the proximal end 8 of the catheter hub 4, thereby releasing the needle shield assembly 120 from the catheter hub. The retaining member 146 is positioned to engage the needle shaft at the sharp needle tip 36, thereby preventing the coupling arm from being pushed in the opposite direction in the needle shield housing and the opening 168 in the coupling arm from realigning with the needle tip 36.

[0104] As shown in the drawings, the needle shaft 34 extends through an opening 170 in the proximal wall 130 of the needle shield housing 122. In a distal portion of the needle shaft spaced from the needle tip 36, the needle 30 is provided with a ridge in the form of a fold 172. In the prepared position, the fold 172 is located within the catheter 10. The diameter of the fold 172 is greater than the radial dimension of the opening 170 in the proximal wall 130 of the needle shield housing 122. Figure 5 and Figure 5a In the protection position shown in FIG. 1 , the needle tip 36 is within the needle shield housing 122. The needle well 142 is used to prevent the needle 30 from moving distally relative to the needle shield assembly 120. The fold 172 engaged with the proximal wall 130 prevents the needle 30 from moving further proximally relative to the needle shield assembly 120, as shown in FIG. Figure 5a . A metal washer 174 may be disposed on the inner surface of the proximal wall 130 to engage with the pleats and prevent the pleats 172 from being inadvertently pulled out through the proximal wall. This allows the needle guard housing 122 to be formed of a relatively soft material, such as molded plastic.

[0105] Steering Figure 6 , an alternative embodiment of the device of the present invention is shown in the figure. The device of this embodiment, generally indicated as 202, includes: a catheter hub, a catheter, a needle hub and a needle, a valve assembly and a valve opener, and a Figure 1 and Figure 2 The embodiment is an extension tube of the same general construction as described above. Figure 6 Examples and Figure 1 and Figure 2 Identical features of the embodiments are denoted by the same reference numerals. Figure 6 Embodiments also include a needle shield assembly including a Figure 4 and Figure 5 A needle guard of the same general construction as in the embodiment above. Figure 6 Examples and Figure 4 and Figure 5 Identical features of the embodiments are denoted by the same reference numerals.

[0106] Figure 6 The device is shown in the ready position. Figure 6In the needle shield assembly 120, the needle shield housing 122 is completely located outside the catheter hub 4. The needle shield assembly 120 is connected to one side of the flange 166 at the proximal end of the catheter hub 4, such as Figure 4 In order to stabilize the needle shield housing 122 on the proximal end of the catheter hub 4, the needle shield housing is provided with an outer distal arm 210 extending on the opposite side from the distal end 126 of the housing to the coupling arm 160. At the proximal end of the catheter hub, on the opposite side of the engagement of the catheter hub with the coupling arm 160, the outer distal arm 210 engages with the outer flange 166.

[0107] When the needle is retracted to the protected position, the coupling arm 160 and its hook 164 are released from the flange 166 of the catheter hub 4. Thus, the outer distal arm 210 is released from engagement with the flange 166 and the needle shield assembly 120, and the needle tip 36 blocked therein can be removed from the catheter hub 4.

[0108] Steering Figure 7a-7c , an embodiment of a valve assembly used in the distal portion 42 of the catheter hub 4 will now be described.

[0109] Reference Figure 7a , a longitudinal cross-sectional view of a valve assembly for a catheter assembly of the present invention is shown. The valve assembly, generally indicated as 702, is formed of a flexible material that is impermeable to liquids and gases. The valve assembly 702 includes a first valve portion 704 that is generally tubular and a second valve portion in the form of a valve disc 706 at the proximal end of the first valve portion.

[0110] Figure 7b and Figure 7c 706 of an embodiment of a valve assembly 702 is shown in FIG. The valve assembly 702 may have a generally circular cross-section, such as Figure 7b Alternatively, the valve assembly 702 may be substantially flat and have an elliptical cross-section, such as Figure 7c The shape of that portion of the inner chamber 12 within the distal portion 42 of the catheter hub 4 will conform to the valve assembly 702 so that the valve assembly fits tightly within the chamber and the first valve portion 704 is in close contact with the inner surface of the chamber, thereby providing a fluid-tight seal between the valve assembly and the inner surface of the catheter hub.

[0111] The valve disc 706 has a plurality of slits 708 disposed therein. Figure 7b and Figure 7c The embodiments shown in each have a series of three slits extending radially outward from the center of the valve disc 706. Other arrangements of slits 708 in the valve disc 706 are also possible, such as a single slit.

[0112] In the ready position, the needle rod 34 extends through the valve disc 706. The needle rod keeps the slit 708 open enough to allow gas to pass through the valve disc, especially in the proximal direction, but not enough to allow blood to pass through the valve disc. In this way, a flashback indication can be provided to the user, as described above.

[0113] As described above, the valve disc 706 is resilient. In particular, when activated by inserting a male connector into the proximal end 8 of the catheter hub 4, the valve opener 50 moves in the distal direction against the resilient bias of the valve disc. When the connector is removed, the valve disc pushes the valve opener in the proximal direction, thereby allowing the valve disc to close and seal the interior chamber of the catheter hub.

[0114] As described above, in the ready position, the needle guard may have an arrangement that remains within the catheter hub. Figure 8 A preferred embodiment of such a needle shield is shown in FIG. The needle shield, generally indicated as 802, takes the form of a needle clip, which is made of an elastic material (e.g. metal), and has arms 804, 806 extending in the distal direction from opposite sides of a proximal wall 810. The proximal wall 810 has a hole 812 for the passage of the needle. The needle shaft is provided with a ridge proximal to the needle tip, for example in the form of a corrugation, as described above and shown in the accompanying drawings. The diameter of the hole 812 in the proximal wall 810 of the needle clip 802 is smaller than the maximum transverse dimension of the needle at the ridge, so that the needle clip 802 is held in a protective position on the needle tip by means of the ridge.

[0115] exist Figure 8 In the embodiment shown in, arms 804, 806 intersect and extend on both sides of the needle and each has an end 820, 822 at its distal end, which is widened to approximately the width of the proximal wall 810 and is located on the outer circumference of the needle in the ready position under elastic pretension. Alternatively, the arm need not cross the needle bar but can extend along the opposite side of the needle bar. When reaching the needle tip, the distal end portion 820, 822 is moved to the protection position using a spring action, wherein the two widened ends 820, 822 engage and block the needle tip. For this reason, the distal ends 820, 822 of the arms 804, 806 are slightly offset in the longitudinal direction relative to each other or the arms 804, 806 have different lengths, thereby ensuring that the two distal end portions 820, 822 of the arm engage on the needle tip. Alternatively, only the longer arm 806 can have an end 822 for blocking the needle tip. Preferably, the longer arm 806 has a terminal portion 824 that curves inwardly at the free edge to ensure that the needle tip is covered, and the inwardly curved end portion 824 still hooks the needle tip even if an attempt is made to push the needle clamp 802 back onto the needle from the protective position. For example, the needle clamp 802 as a whole can be made very compact and only about 7 mm in length.

[0116] The present invention also provides the following implementation modes.

[0117] Implementation Method 1

[0118] A catheter assembly, comprising: a catheter hub having a chamber therein, the catheter hub having a distal end and a proximal end, the catheter hub being connectable at its proximal end to a device for infusing fluid into the chamber in the catheter hub or withdrawing fluid from the chamber; a hollow tubular catheter having a proximal end and a distal end, the catheter being connected at its proximal end to the distal end of the catheter hub, the interior of the catheter leading into the chamber in the catheter hub; a needle having a sharp needle tip, in a prepared position, the needle extending through the chamber in the catheter hub and the catheter and the needle tip extending beyond the distal end of the catheter; a hollow extension tube having a distal end and a proximal end, the extension tube being connected at its distal end to the proximal and distal ends of the catheter hub The extension tube opens into a chamber in the catheter hub at its distal end, and the extension tube can be connected to a device for infusing fluid into the chamber in the catheter hub at its proximal end; a valve assembly is arranged in the chamber of the catheter hub, and the valve assembly includes: a first valve component, which closes the distal end of the extension tube and can be opened under the action of pressurized fluid in the extension tube; and a second valve component, which prevents fluid from flowing through the chamber to the proximal end of the catheter hub or out of the proximal end of the catheter hub, and the second valve component is a two-way valve and can be opened to allow fluid to flow through the chamber in the catheter hub in the distal direction and the proximal direction.

[0119] Implementation Method 2

[0120] The catheter assembly as described in embodiment 1, wherein the distal hub portion of the catheter hub is substantially flat.

[0121] Implementation 3

[0122] A catheter assembly as described in embodiment 2, wherein the extension tube leads to a distal hub portion of the catheter hub.

[0123] Implementation 4

[0124] The catheter assembly of any of the preceding embodiments, wherein the needle comprises an opening in the shaft of the needle in a distal portion of the needle.

[0125] Implementation method 5

[0126] A catheter assembly as described in embodiment 4, wherein the opening is disposed within the catheter in the preparation position.

[0127] Implementation 6

[0128] The catheter assembly of any of the preceding embodiments, wherein the first valve component is a one-way valve between the extension tube and an interior chamber of the catheter hub.

[0129] Implementation 7

[0130] A catheter assembly as described in any of embodiments 1 to 5, wherein the first valve component is a two-way valve between the extension tube and the inner chamber of the catheter hub.

[0131] Implementation 8

[0132] A catheter assembly as described in embodiment 7, wherein the first valve component includes one or more slits therein that are aligned with the opening of the extension tube.

[0133] Implementation method 9

[0134] The catheter assembly of any of the preceding embodiments, wherein the first valve component comprises an elastic valve body.

[0135] Embodiment 10

[0136] A catheter assembly as described in embodiment 9, wherein the valve body is a tubular body.

[0137] Implementation 11

[0138] A catheter assembly as described in embodiment 10, wherein the tubular body is disposed in an inner chamber of the catheter hub and contacts an inner surface of a wall of the catheter hub.

[0139] Implementation 12

[0140] The catheter assembly of any of the preceding embodiments, wherein the second valve component comprises a resilient valve disc extending laterally across an interior chamber of the catheter hub.

[0141] Implementation 13

[0142] A catheter assembly as described in embodiment 12, wherein the disk has one or more slits disposed therein.

[0143] Implementation 14

[0144] The catheter assembly of any of the preceding embodiments, wherein in the ready position, the second valve component forms a seal around the needle shaft.

[0145] Implementation 15

[0146] A catheter assembly as described in embodiment 14, wherein the seal allows gas to escape through the second valve component but prevents blood from passing through the second valve component.

[0147] Implementation 16

[0148] The catheter assembly as described in any of the above embodiments further includes a valve opener, which is disposed in the inner chamber of the catheter hub and is located proximal to the valve assembly.

[0149] Implementation 17

[0150] A catheter assembly as described in embodiment 16, wherein the valve opener has a channel therethrough or adjacent thereto for fluid to pass therethrough.

[0151] Implementation 18

[0152] The catheter assembly as described in any of the preceding embodiments further comprises a needle guard assembly.

[0153] Implementation 19

[0154] A catheter assembly as described in embodiment 18, wherein the needle guard assembly is completely or partially disposed in the inner chamber of the catheter hub.

[0155] Implementation Method 20

[0156] The catheter assembly of embodiment 19, wherein the needle shield assembly is releasably engaged with the catheter hub so that the needle has a protected position, wherein the needle shield assembly blocks the needle tip when the needle shield assembly is released from the catheter hub.

[0157] Implementation 21

[0158] A catheter assembly as described in embodiment 18, wherein the needle guard assembly is disposed outside the catheter hub.

[0159] Implementation Method 22

[0160] The catheter assembly of any one of embodiments 18 to 21, wherein, in the ready position, the needle guard assembly is releasably engaged with the catheter hub.

[0161] Implementation 23

[0162] A catheter assembly as described in embodiment 22, wherein movement of the needle to a protected position releases the needle shield assembly from engagement with the catheter hub.

[0163] Implementation Method 24

[0164] The catheter assembly of any one of Embodiments 18 to 23, wherein the needle guard assembly comprises a needle guard housing.

[0165] Implementation 25

[0166] The catheter assembly of any one of embodiments 18 to 24 further includes a device for limiting movement of the needle in a proximal direction relative to the needle shield assembly.

[0167] Implementation 26

[0168] A catheter assembly as described in embodiment 25, wherein the restriction device includes a protrusion in the distal portion of the needle shaft.

[0169] Implementation 27

[0170] A catheter assembly as described in embodiment 26, wherein the protrusion is non-circular.

[0171] Implementation 28

[0172] A catheter assembly as described in embodiment 26 or 27, wherein the needle shield assembly includes a proximal wall having an opening therein, the needle rod extends through the opening in the proximal wall, and the radial dimension of the protrusion is greater than the radial dimension of the opening in the proximal wall.

[0173] Implementation 29

[0174] A catheter assembly as described in any of embodiments 26 to 28, wherein, in the preparation position, the protrusion is located within the catheter.

[0175] Embodiment 30

[0176] A needle shield assembly for a catheter assembly, the needle shield assembly comprising:

[0177] a housing for receiving a needle extending therethrough and having a distal end and a proximal end, the housing being connectable at its distal end to the proximal end of the catheter hub;

[0178] A needle shield is arranged in the housing, and the needle shield comprises:

[0179] a needle trap movable between a ready position in which the needle trap is held to one side of the shaft of the needle extending through the housing and a protected position in which the needle trap blocks the sharp tip of the needle within the housing;

[0180] an elastic arm biasing the needle trap to a protection position, the elastic arm being supported on an inner wall of the housing to push the needle trap to the protection position;

[0181] A coupling arm couples the housing to the proximal end of the catheter hub in a ready position, wherein movement of the needle trap from the ready position to the protected position causes the coupling arm to release the housing from the catheter hub.

[0182] Implementation Method 31

[0183] The needle guard assembly of embodiment 30, wherein, in the ready position, the needle guard housing has a portion extending into the proximal end of the catheter hub.

[0184] Implementation 32

[0185] A needle shield assembly as described in embodiment 30 or 31, wherein the needle trap is pivotally attached to the resilient arm at a first end.

[0186] Implementation 33

[0187] A needle shield assembly as described in any one of embodiments 30 to 32, wherein, in the ready position, the needle well and the elastic arm are folded together to one side of the needle shaft.

[0188] Implementation 34

[0189] A needle guard assembly as described in any of embodiments 30 to 33, wherein the needle well includes one or more side members extending from each side of the needle well in a proximal direction.

[0190] Implementation 35

[0191] A needle guard assembly as described in any of embodiments 30 to 34, wherein the needle trap includes a retaining component that prevents the needle trap from moving from the protection position to the ready position.

[0192] Implementation 36

[0193] A needle guard assembly as described in any of embodiments 30 to 35, wherein the coupling arm engages with the exterior of the proximal end of the catheter hub.

[0194] Implementation 37

[0195] A needle guard assembly as described in any of embodiments 30 to 36, wherein the coupling arm is connected to the second end of the needle well.

[0196] Implementation 38

[0197] A needle shield assembly as described in any of embodiments 30 to 37, wherein the coupling arm includes an opening therein, and in the ready position, the needle extends through the opening.

[0198] Implementation 39

[0199] A needle shield assembly as described in any one of embodiments 30 to 38, wherein the needle shield housing includes a proximal wall having an opening therein, the needle rod extending through the opening in the proximal wall, the opening being used to engage with a protrusion in the needle rod, the radial dimension of the protrusion being larger than the radial dimension of the opening in the proximal wall.

[0200] Embodiment 40

[0201] A needle guard assembly as described in embodiment 39, wherein an area of ​​the proximal wall adjacent to the opening is reinforced.

[0202] Implementation 41

[0203] The catheter assembly as described in embodiment 1 also includes a needle sheath assembly as described in any one of embodiments 30 to 40.

Claims

1. A catheter assembly, comprising: a catheter hub having a chamber therein, the catheter hub having a distal end and a proximal end, the catheter hub being connectable at its proximal end to a device for infusing fluid into or withdrawing fluid from the chamber of the catheter hub; a hollow tubular catheter having a proximal end and a distal end, the catheter being connected at its proximal end to the distal end of the catheter hub, the interior of the catheter opening into the chamber of the catheter hub; a needle having a sharpened needle tip, wherein in a prepared position, the needle extends through the chamber of the catheter hub and the catheter and the needle tip extends beyond the distal end of the catheter; a flexible, hollow extension tube having a distal end and a proximal end, the flexible, hollow extension tube being connected at its distal end between the proximal and distal ends of the catheter hub, the flexible, hollow extension tube opening at its distal end into a chamber of the catheter hub, the extension tube being connectable at its proximal end to a device for infusing a fluid into the chamber of the catheter hub; A valve assembly is disposed in the chamber of the catheter hub, the valve assembly comprising: a first valve member closing the distal end of the flexible, hollow extension tube and capable of opening in response to pressurized fluid within the flexible, hollow extension tube; and a second valve component disposed in the chamber of the catheter hub at a position proximal to the opening at the distal end of the extension tube and proximal to the first valve component, the second valve component preventing fluid from flowing through the chamber to or from the proximal end of the catheter hub, the second valve component being a two-way valve and being openable to allow fluid to flow through the chamber of the catheter hub in both a distal direction and a proximal direction; and a needle shield assembly releasably engageable with the catheter hub such that the needle has a protected position, wherein the needle shield assembly blocks the needle tip when the needle shield assembly is released from the catheter hub, the needle shield assembly comprising: a housing through which the needle extends and having a distal end and a proximal end, the housing being connected at its distal end to the proximal end of the catheter hub; A needle shield is arranged in the housing, and the needle shield comprises: a needle trap movable between a ready position in which the needle trap is held to one side of the needle shaft of the needle extending through the housing and a protected position in which the needle trap blocks the sharp tip of the needle within the housing, the needle trap comprising a first end, a second end, a lateral member or side member extending in a proximal direction from the needle trap, and a retaining member; a resilient arm biasing the needle trap to the protection position, the resilient arm being supported on the inner wall of the housing to push the needle trap to the protection position, wherein in the ready position, the needle trap and the resilient arm are folded together to one side of the needle shaft of the needle; a coupling arm that couples the housing to a proximal end of the catheter hub in the ready position, wherein movement of the needle trap from the ready position to the protected position causes the coupling arm to release the housing from the catheter hub, wherein the coupling arm is connected to a second end of the needle trap along a line extending perpendicular to a needle shaft of the needle; Wherein, when the needle trap moves from the preparation position to the protection position, the elastic arm rotates relative to the needle in a first direction and the needle trap rotates relative to the needle in a second direction, the second direction being opposite to the first direction; wherein, when the needle trap is in the protection position, the retaining member is configured to be positioned to engage with the needle shaft of the needle at the sharp needle tip of the needle to prevent the needle trap from moving from the protection position to the ready position; and The lateral component or the lateral component and the retaining component are configured to prevent the needle trap from moving lateral relative to the needle and to prevent the needle tip from being exposed.

2. The catheter assembly of claim 1, wherein: The catheter hub includes a distal hub portion and a proximal hub portion, the distal hub portion being generally flat.

3. The catheter assembly of claim 2, wherein: The flexible, hollow extension tube leads to a distal hub portion of the catheter hub.

4. The catheter assembly according to any one of claims 1 to 3, wherein: The needle includes an opening in a shaft of the needle in a distal portion of the needle.

5. The catheter assembly of claim 4, wherein: In the preparation position the opening is arranged in the conduit.

6. The catheter assembly of any one of claims 1-3 and 5, wherein: The first valve component is a one-way valve between the flexible, hollow extension tube and the chamber of the catheter hub.

7. The catheter assembly of any one of claims 1-3 and 5, wherein: The first valve component is a two-way valve between the flexible, hollow extension tube and the chamber of the catheter hub.

8. The catheter assembly of claim 7, wherein: The first valve member includes one or more slots therein that align with the opening of the flexible, hollow extension tube.

9. The catheter assembly of any one of claims 1-3, 5 and 8, wherein: The first valve member includes an elastic valve body.

10. The catheter assembly of claim 9, wherein: The valve body is a tubular body.

11. The catheter assembly of claim 10, wherein: The tubular body is disposed in the chamber of the catheter hub and contacts an inner surface of a wall of the catheter hub.

12. The catheter assembly of any one of claims 1-3, 5, 8, and 10-11, wherein: The second valve member includes a resilient valve disc extending laterally across a chamber of the catheter hub.

13. The catheter assembly of claim 12, wherein: The elastic valve disc is provided with one or more slits therein.

14. The catheter assembly of any one of claims 1-3, 5, 8, 10-11 and 13, wherein: In the ready position, the second valve member forms a seal around the shaft of the needle.

15. The catheter assembly of claim 14, wherein: The seal allows gas to escape through the second valve member but prevents blood from passing through the second valve member.

16. The catheter assembly of any one of claims 1-3, 5, 8, 10-11, 13 and 15, further comprising a valve opener disposed in a chamber of the catheter hub proximal to the valve assembly.

17. The catheter assembly of claim 16, wherein: The valve opener has a passage therethrough for passage of fluid.

18. The catheter assembly of any one of claims 1-3, 5, 8, 10-11, 13, 15 and 17, wherein: The needle guard assembly is fully or partially disposed in a chamber of the catheter hub.

19. The catheter assembly of any one of claims 1-3, 5, 8, 10-11, 13, 15 and 17, wherein: The needle guard assembly is disposed outside of the catheter hub.

20. The catheter assembly of any one of claims 1-3, 5, 8, 10-11, 13, 15, and 17, wherein: In the ready position, the needle guard assembly is releasably engaged with the catheter hub.

21. The catheter assembly of claim 20, wherein: Movement of the needle to the protected position releases the needle shield assembly from engagement with the catheter hub.

22. The catheter assembly of any one of claims 1-3, 5, 8, 10-11, 13, 15, 17, and 21, wherein: The needle guard assembly includes a needle guard housing.

23. The catheter assembly of any one of claims 1-3, 5, 8, 10-11, 13, 15, 17 and 21, further comprising means for limiting movement of the needle in a proximal direction relative to the needle guard assembly.

24. The catheter assembly of claim 23, wherein: The means for limiting movement of the needle comprises a protuberance in a distal portion of the needle shaft of the needle.

25. The catheter assembly of claim 24, wherein: The protrusion is non-circular.

26. The catheter assembly of claim 24 or 25, wherein: The needle shield assembly includes a proximal wall having an opening therein, the shaft of the needle extending through the opening in the proximal wall, and the radial dimension of the protuberance is greater than the radial dimension of the opening in the proximal wall.

27. The catheter assembly of any one of claims 24 or 25, wherein: In the prepared position, the protuberance is located within the catheter.

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