DESC:FIELD OF THE INVENTION

The present invention generally relates to intravenous catheter assemblies used for vascular access. More particularly, the present invention relates to a pressure actuated flow control valve and mechanism for an intravenous catheter assembly which permits gravity flow of a liquid through the catheter and into a patient while preventing back flow of blood from the patient and into the catheter. The intravenous catheter assembly can be used, not being limited to, for gaining vascular access for blood removal and/or blood re-infusion to a patient during a medical procedure, for example dialysis etc.

BACKGROUND OF THE INVENTION

An intravenous catheter assembly of this kind is generally known. Catheter assemblies are used to place a catheter properly into the vascular system of a patient. Once in place, catheters such as intravenous ("IV") catheters may be used to infuse fluids including normal saline, medicinal compounds, and/or nutritional compositions or the like into a patient in need of such treatment. Catheters additionally enable the removal of fluids for example, blood from the circulatory system and monitoring of conditions within the vascular system of the patient.

Medical infusion therapy including infusion, removal and/or re-infusion employs peripheral and central intravascular devices such as venous and arterial catheters as well as peripherally inserted central venous catheters, for example to deliver fluids, blood products, and pharmaceuticals, including antibiotics and biologics as well as parenteral nutrition.

Blood reflux into central line and other types of vascular catheters can lead to intraluminal thrombosis, creating a full or partial occlusion of the IV access device. Such occlusions can interfere with IV therapy, provide a nutrient-rich area for pathogenic bacteria, or be detached from the catheter, leading to venous thrombosis. Even in cases where intraluminal thrombosis does not lead to further health complications, such a condition requires the replacement of the catheter, a procedure which can be both time consuming and lead to injury at the removal site and the new introduction site.

Regardless of the location of the insertion site of the catheter or the placement of its terminus, intravascular devices, and central venous catheters (CVCs) in particular, are subject to retrograde blood flow into the catheter lumen whenever the pressure in the patient's vascular system exceeds resistance at the supply end of the catheter. This may occur, for example, when fluid pressure drops because a gravity supply source is empty, when an injection port is opened by removal of a syringe, or when a stopcock is opened.

Retrograde blood flow is known to contribute to complications such as catheter-related septicemia, venous thrombosis, superior vena cava syndrome, pulmonary embolism and phlebitis. Thrombus formation may cause partial or complete occlusion of the catheter. Partial occlusion results in impaired sampling and fluid administration. Complete occlusion causes the catheter to lose patency, necessitating removal and replacement, so-called “unscheduled restarts”.

Catheter reflux-induced thrombosis is not merely a mechanical complication, since it appears to be a major contributor to catheter related bloodstream infections associated with the use of long term catheters. Such infections are associated with increased morbidity and mortality as well as increased health care costs associated with extended hospitalization.

All of the preventive methods and devices that are currently available appear to contribute in some manner to general health care delivery problems, such as delay, increased requirements for nursing care, pharmaceutical and supply costs, increased patient risk, risk of infections and discomfort.

Accordingly, there is a need for an improved catheter assembly and/or a vascular access catheter assembly with more reliable sealing functionality and mechanism which effectively prevents anti-reflux of blood and which is simple in construction and use. Such a catheter assembly is disclosed herein.

OBJECTS AND SUMMARY OF THE INVENTION

An object of the present invention is to provide an improved intravenous catheter assembly and/or a vascular access catheter assembly which is inexpensive to manufacture, efficient, effective and simple in its construction and use.

It is another object of the present invention to provide an intravenous catheter assembly which has better blood control features.

It is another object of the present invention to provide a compact design for housing one or more valves within the catheter hub housing of the intravenous catheter assembly having better blood control features.

It is another object of the present invention to provide a pressure actuated flow control valve and mechanism which allows a safe and reliable control of the fluid or blood flow through the catheter assembly depending on the actual demands for the therapy of a patient. The pressure actuated valve is easy to manufacture and reliable and easy to handle in practical use.

A pressure actuated flow control valve and mechanism for an intravenous catheter assembly comprising: a catheter hub and a catheter tube each having a proximal end and a distal end, wherein a proximal portion of the catheter hub having an inner housing defining a chamber; a needle having a distal and a proximal end; a needle hub attached to the proximal end of the needle; a valve fixedly retained together with a valve stopper within the chamber of the catheter hub in a distal region thereof; a valve actuating member having a distal and a proximal end defining a passageway for the needle to pass therethrough in a ready position; a spring having a proximal and a distal end movably arranged within the chamber over the valve actuating member.

The needle movably extends through the chamber of the catheter hub and through the catheter tube in the ready position.

A valve is fixedly retained together with a valve stopper within the chamber of the catheter hub in a distal region thereof wherein the valve stopper having a distal and a proximal face/end and an opening running thoroughly therethrough. The opening allows the needle and/or the valve actuating member to pass therethrough in the ready position. The valve is provided with one or more self-sealing slit(s) and/or hole(s) allowing the needle to pass therethrough in the ready position.

A spring having a proximal and a distal end movably arranged being in an uncompressed and/or expanded state within the chamber over the valve actuating member. The valve actuating member having a distal and proximal end defining a passageway for the needle to pass therethrough in ready position wherein the distal end of the spring fixedly engaged with a first retaining member provided at the proximal end of the valve stopper and the proximal end of the spring fixedly retained by a second retaining member provided on the valve actuating member.

The valve has a dome portion forming a distal face coupled with a lip portion or radial flange extending in a direction opposite to axial A direction. The dome portion has a curved profile and/or a semi-spherical profile forming the distal face. The curve of the curved profile of the valve extends in a direction opposite to the axial direction A. The curved profile of the dome portion facilitates in closure of the self-sealing slit(s) and/or hole(s) effectively once the needle is retracted out of the catheter hub. In alternative embodiment, the curve of the curved profile of the valve may extend in the axial direction A.

The valve having the dome portion and lip portion are of unitary construction and are made of a resilient medical grade elastomeric material such as a silicon elastomer, rubber, silicon rubber, neutral rubber etc. The distal face of the valve stopper fixedly supports the lip portion of the valve keeping the valve fixedly retained in position within the chamber of the catheter hub.

The valve stopper may be constructed of a medical grade rigid or semirigid synthetic resinous material suitable for supporting the valve in a stable manner, such as, for example, polyvinyl chloride or polycarbonate or metal or the like.

The valve actuating member has varying inner diameter in between the proximal and distal ends. The inner diameter of the passageway in a proximal region of the valve actuating member is slightly larger than the outer diameter of the needle shaft in order to allow a slidable movement of the needle through the passageway in ready position. Whereas the inner diameter of passageway being larger than the inner diameter at the proximal end region of the passageway is configured to receive a connection assembly such as needle less injection, or other handling devices or medical device assemblies, dialysis needle free connection assemblies that may or may not contain piercing elements.

The spring is arranged being in contact with an inner surface of the chamber having sufficient clearing for the valve actuating member to be slidably retained within the chamber. In an alternative embodiment, the spring is arranged not being in contact with an inner surface of the chamber having sufficient clearing for the valve actuating member to be slidably retained within the chamber. The distal end of the spring is fixedly engaged with a first retaining member provided at the proximal end of the valve stopper. The proximal end of the spring is fixedly retained by a second retaining member provided on the valve actuating member. It is to be understood that the spring stores energy when in compressed state. The valve actuating member serves to open the valve.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

Embodiments of the present disclosure now will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the present disclosure are shown. This present disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the claims to those skilled in the art. Like numbers refer to like elements throughout. The embodiments of the invention are described in the following description and in the accompanying drawings, wherein:

Fig. 1 illustrates a longitudinal view of an intravenous catheter assembly in the ready position according to the present invention.

Fig. 2 illustrates a longitudinal sectional view of the intravenous catheter assembly in a pre-use ready position according to the present invention.

Fig. 3 illustrates a longitudinal sectional view of the intravenous catheter assembly with a hollow needle being connected to a needle hub removed in a post-use position according to the present invention.

Fig. 4 illustrates a longitudinal sectional view of the intravenous catheter assembly with a valve actuating member opening the pressure actuated flow control valve according to the present invention.

DESCRIPTION OF THE INVENTION

Embodiments of the presently disclosed invention will now be described in detail with reference to the drawings wherein like reference numerals designate identical or corresponding elements. In the drawings and in the description, the term "proximal", "top", "up" or "upper" refers to a location on the device that is closest to the clinician using the device and farthest from the patient in connection with whom the device is used when the device is used in its normal operation. Conversely, the term "distal", "bottom", "down" or "lower" refers to a location on the device that is farthest from the clinician using the device and closest to the patient in connection with whom the device is used when the device is used in its normal operation. For example, the distal region of a needle will be the region of the needle containing the needle tip which is to be inserted e.g. into a patient's vein.

In this context, the end of the needle having the sharp tip of the needle is denoted as the distal end, whereas the opposite end of the needle is denoted as the proximal end. Likewise, the orientation of parts of other structural elements facing towards the needle tip will be referred to as distal, whereas the orientation of parts of these structural elements facing in the opposite direction will be referred to as proximal.

The needle extends in an axial direction towards the tip, thereby defining an axial direction A for the intravenous catheter assembly.

As used herein “pre-use and/or ready position” means the catheter assembly is ready for use, such as to perform a venipuncture or intravenous access. Sometimes the ready position first requires removing a protective cap from the catheter assembly or needle assembly. The protective cap can be included for packaging.

As used herein “post-use position” means the catheter assembly in particular the needle hub having a needle is ready for disposal being safely withdrawn from the catheter assembly post a successful venipuncture.

While described herein in terms of one of the embodiments of an intravenous catheter assembly, the catheter assembly of the present invention may be used with or incorporate other medical devices used in connection with medical procedure, for example dialysis etc., such as a connection assembly comprising luer lock (male or female), dialysis needle free connection assemblies, hypodermic syringe assembly, a hypodermic needle, a single and/or double ended needle assembly for blood collection, an intravenous infusion set, needle less injection, or other handling devices or medical device assemblies that may or may not contain piercing elements.

In Figs. 1 and 2 a longitudinal and longitudinal sectional view respectively of an intravenous catheter assembly 10 in a ready position according to the present invention are shown. The intravenous catheter assembly 10 generally comprises various features and elements for gaining vascular access for blood removal and/or blood re-infusion to a patient during a medical procedure, for example dialysis etc. As can be seen, the intravenous catheter assembly 10 is provided with a catheter hub 12 and a catheter tube 14 each having a proximal end and a distal end. The catheter tube 12 is attached to the catheter hub 12 at a distal end of the catheter hub 12. A proximal portion 16 of the catheter hub 12 has an inner housing which defines a chamber 18 of generally circular cross-section. The catheter tube 14 can generally include a biocompatible material that is made of a flexible or semi-flexible polymer.

One or more hole and/or slit and/or perforation 30 are provided at the distal end of the catheter hub 12 which facilitate suction and/or movement of the extra fluid including blood therethrough post a successful venipuncture within the lumen of the catheter tube 14.

A needle 20 having a distal and a proximal end movably extend through the chamber 18 of the catheter hub 12 as well as through the catheter tube 14. The needle 20 comprises a needle shaft 22 and a needle tip 24 at its distal end. A needle hub 26 having a proximal end and a distal end is attached to the proximal end of the needle 20. The proximal end of the needle hub 26 has a flash back chamber 28 being in fluid/blood connection with the lumen of the needle shaft 22. The distal end of the needle hub 26 defines a retaining end 60 movably arranged to be in retaining contact with a proximal end of the catheter hub 12. The needle 20 defines said axial (longitudinal) direction A and the needle shaft 22 has a generally constant principal profile. An enlargement of the radial dimension (not shown) of the needle 20 in at least one direction as compared to the principal profile may be provided being positioned in the region of the needle tip 24 which may act as an engagement means. Preferably, such engagement means is made by crimping of the needle 20. However, it could also be made by welding, milling, cold heading or expanding the needle 20. The function of the engagement means becomes relevant in case a needle guard is used to cover/protect the needle tip 24.

In the region of its proximal end, the needle 20 is connected in a leak free manner, for example glued, to the needle hub 26. The needle 20 has a lumen extending through needle 20 from proximal to distal end. The proximal end of the needle 20 is beveled to define a sharp puncture tip 24, such as intravenous puncture tip. Puncture tip 24 is provided for insertion into a patient's skin and blood vessel, such as a vein, and is therefore designed to provide ease of insertion and minimal discomfort during venipuncture.

In the ready position as shown in Figs. 1 and 2, the needle 20 extends all the way through chamber 18 of the catheter hub 12 as well as the catheter tube 14 and the needle tip 24 protrudes from a distal end of the catheter tube 14. It is to be noted that the needle 20 is fixed in its ready position by the needle hub 26 engaging with the catheter hub 12 in that the proximal portion of the catheter hub 12 is movably received by the distal portion of the needle hub 26.

Further, the catheter hub 12 may be provided with wings 32 which in use may be adhesively taped to the skin of the patient at the venipuncture site to maintain the catheter assembly/device 10 stationery during use. As shown in Figs. 1 and 2, the wings 32 may be integrally formed with the catheter hub. Alternatively, the present disclosure encompasses separate wing(s) 32 that may be affixed to the catheter hub 12. In case of separate wings 32, the wings 32 may comprise a catheter hub alignment features (not shown) configured to align and orient with the catheter hub 12. Whereas the catheter hub 12 may be provided with wing alignment features (not shown) to receive the wings 32. The catheter hub alignment features and the wing alignment features are configured to align and orient the catheter hub 12 and the wings 32 with each other. The alignment features may include one or more projections and/or grooves being integrally formed vice-versa on the catheter hub 12 and wings 32 for a working engagement therebetween. The interaction of the wing alignment features and the catheter alignment features provides that the wings 32 are properly aligned and oriented with the catheter hub 12 and can be safely and easily assembled. Further, the interaction of the wing alignment features and the catheter alignment features provide that the wings 32 cannot move into distal or proximal direction and cannot rotate with respect to the catheter hub 12 after assembly.

Each wing 32 member may be made of a soft material, which may be selected from thermoplastic elastomers (TPE), polyvinylchloride (PVC), isoprene, rubber, ethylenevinylacetate (EVA), and other elastomeric or resilient materials. Each wing member may be made of a rigid material, for instance comprising polypropylene (PP). Each wing member 32 may also be made of a combination of a soft and a rigid material selected from the above materials.

Referring now to the ready position as shown in Fig. 2, a valve 34 is fixedly retained together with a valve stopper 36 within the chamber 18 of the catheter hub 12 in a distal region thereof. The valve stopper 36 has a distal and proximal face/end and an opening 50 running therethrough. The opening 50 allows the needle 20 and/or a valve actuating member 40 to pass therethrough in the ready position. Further, the valve 34 is provided with one or more self-sealing slit(s) and/or hole(s) 52 allowing the needle 20 to pass therethrough in ready position as shown in Fig. 2. When the needle 20 is retracted, the valve 34 in particularly the self-sealing slit(s) and/or hole(s) 52 automatically close as is shown in Fig. 3 preventing any outflow of blood or fluid therefrom.

As can be seen, the valve 34 has a dome portion 56 forming a distal face coupled with a lip portion or radial flange 58 extending in a direction opposite to axial A direction. In alternative embodiments, valve 34 can be without the lip portion 58. The dome portion 56 has a curved profile and/or a semi-spherical profile forming the distal face as shown in Fig. 3 once the needle 20 is retracted out of the catheter hub 12. The curve of the curved profile of the valve 34 extends in a direction opposite to the axial direction A. In alternative embodiment, the curve of the curved profile of the valve 34 may extend in the axial direction A. The curved profile of the dome portion 56 facilitates in closure of the self-sealing slit(s) 52 effectively once the needle is retracted out of the catheter hub 12. In the alternative embodiments, the dome portion 56 of the valve 34 may be without any curved profile. The self-sealing slit(s) 52 are configured to extend across the fluid flow path for providing fluid communication through the valve 34 when it is in an open position as shown in Fig. 2.

The valve 34 having the dome portion 56 and lip portion 58 are of unitary construction and made of a resilient medical grade elastomeric material such as a silicon elastomer, rubber, silicon rubber, neutral rubber etc.

The distal face of the valve stopper 36 fixedly supports the lip portion 58 of the valve 34 keeping the valve 34 fixedly retained in position within the chamber 18 of the catheter hub 12. The valve stopper 36 may be constructed of a medical grade rigid or semirigid synthetic resinous material suitable for supporting the valve 36 in a stable manner, such as, for example, polyvinyl chloride or polycarbonate or metal or the like.

A spring 38 having a proximal and distal end is movably arranged being in an uncompressed and/or expanded state within the chamber 18 over a valve actuating member 40 which as well is movably retained within the chamber 18 in the ready position. It is to be understood that the spring 38 stores energy when in compressed state as shown in Fig. 4. The valve actuating member 40 serves to open the valve 34 as shown in Fig. 4. As can be seen, the spring 38 is movably arranged over the valve actuating member 40. The valve actuating member 40 has a distal and proximal end defining a passageway 44 for the needle 20 to pass therethrough in ready position. The valve actuating member 40 has varying inner diameter in between the proximal and distal ends. The inner diameter of the passageway 44 in a proximal region of the valve actuating member 40 is slightly larger than the outer diameter of the needle shaft 22 in order to allow a slidable movement of the needle 20 through the passageway 44 in ready position. Whereas the inner diameter of passageway 44 being larger than the inner diameter at the proximal region of the passageway 44 is configured to receive a connection assembly such as needle less injection, or other handling devices or medical device assemblies that may or may not contain piercing elements discussed in detail in subsequent paragraphs.

In one embodiment, the spring 38 is arranged being in contact with an inner surface 42 of the chamber 18 having sufficient clearing for the valve actuating member 40 to be slidably retained within the chamber 18. In an alternative embodiment, the spring 38 is arranged not being in contact with an inner surface 42 of the chamber 18 having sufficient clearing for the valve actuating member 40 to be slidably retained within the chamber 18. The distal end of the spring 38 is fixedly engaged with a first retaining member 46 provided at the proximal end of the valve stopper 36. The proximal end of the spring 38 is fixedly retained by a second retaining member 48 provided on the valve actuating member 40. In the ready position, the proximal end of the valve actuating member 40 abuts the retaining end 60 of the needle hub 26 wherein the proximal end of the catheter hub 12 is engageably retained within a housing 54 formed in a distal region of the needle hub 26.

The valve actuating member 40 in the ready position is retained within the chamber 18 such that no part of the valve actuating member 40 exposes out of the chamber 18 of the catheter hub 12 even when the needle 20 is retracted out of the catheter hub 12. In the alternative embodiments though the proximal end of the valve actuating member 40 may expose out of the chamber 18 once the needle 20 is retracted out of the catheter hub 12.

Referring now to Fig. 3, a longitudinal sectional view of the intravenous catheter assembly 10 with a hollow needle 20 being connected to a needle hub removed in a post-use position is shown. It is to be understood that in use, post puncturing a blood vessel of a patient through the needle tip 24, the catheter 14 is inserted into the blood vessel of the patient, so that the catheter lumen is in fluid communication with the patient’s blood where it may remain indwelling for a prolonged period of time.

As can be seen, post a successful venipuncture, the needle 20 (not shown) is retracted in a direction opposite to axial direction A. As soon as the needle tip 24 passes beyond the valve 34 being retracted in a direction opposite to axial direction A, the self-sealing slit(s) 52 of the valve 34 automatically closes preventing any outflow of blood from the catheter 14. The catheter assembly 10 through the wings 32 is adhesively taped to the skin of the patient at the venipuncture site to maintain the catheter assembly/device 10 stationery during or for further medical procedure, for example dialysis etc. Once the needle 20 is retracted out of the catheter hub 12, the valve actuating member 40 keeps being movably retained together with the spring 38 preferably in an expanded position within the chamber 18 of the catheter hub 12. It is to be noted that the spring 38 is arranged being retained between the first 46 and second 48 retaining member in such a manner that no part of the valve actuating member 40 exposes out of the chamber 18 of the catheter hub 12.

Referring now to Fig. 4, a longitudinal sectional view of the intravenous catheter assembly 10 with a valve actuating member 40 opening the pressure actuated flow control valve 34 is shown in case when it becomes necessary to withdraw blood or re-infuse blood/medicines/fluid to a patient. In such instances, a syringe and/or a needle less syringe (not shown), for example dialysis needle free assemblies may be inserted into the catheter hub 12 by exerting a force in the axial direction A. In such a situation, the neck of the connection assembly, for example a needle-less syringe is received and abutted within the passageway 44 of the valve actuating member 40. The further exertion of force on the syringe in axial direction A forces the distal end of the valve actuating member 40 to open the slit(s) of valve 34 establishing a fluid communication between the catheter 14, passageway 44 and the syringe to continue with the infusion and/or blood withdrawing process. In such a state, as can be seen in Fig. 4, the exertion of the force in axial direction A by the syringe causes the spring 38 to compress between the first 46 and second 48 retaining member. Post completion of the medical procedure, once the syringe is retracted out of the passageway 44 of the valve actuating member 40, the spring 38 expands back to its expanded position causing the valve actuating member 40 to retract out of the valve 34 automatically closing the slit 52 of the valve 34 thereby preventing any backflow/outflow of blood from the catheter 14 as shown in Fig. 3.

Those skilled in the art will appreciate that the catheter assembly 10 having the pressure actuated valve can also be used in conjunction with a variety of other medical fluid delivery and/or fluid flow control devices, such as, dialysis procedure, an arterial catheter and associated chemotherapy fluid reservoir and/or pressure monitoring device, or a gastrostomy tube set having a corresponding fluid reservoir.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the present disclosure. As used herein, the term "and/or" includes any and all combinations of one or more of the associated' listed items.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It will be further understood that the terms "comprises" "comprising," "includes" and/or "including" when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this present disclosure belongs. It will be further understood that terms used herein should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Reference numerals

A axial direction
10 intravenous catheter assembly
12 catheter hub
14 catheter tube/catheter
16 proximal portion
18 chamber
20 needle
22 needle shaft
24 needle tip
26 needle hub
28 flash back chamber
30 holes and/or slits and/or perforation
32 wings
34 valve
36 valve stopper
38 spring
40 valve actuating member
42 inner surface of chamber
44 passageway
46 first retaining member
48 second retaining member
50 opening
52 self sealing slit/slit/hole
54 housing
56 dome portion
58 lip portion or radial flange
60 retaining end

,CLAIMS:1. A pressure actuated flow control valve and mechanism for an intravenous catheter assembly (10) comprising:
a catheter hub (12) and a catheter tube (14) each having a proximal end and a distal end, wherein a proximal portion (16) of the catheter hub (12) having an inner housing defining a chamber (18);
a needle (20) having a distal and a proximal end;
a needle hub (26) attached to the proximal end of the needle (20);
a valve (34) fixedly retained together with a valve stopper (36) within the chamber (18) of the catheter hub (12) in a distal region thereof;
a valve actuating member (40) having a distal and a proximal end defining a passageway (44) for the needle (20) to pass therethrough in a ready position;
a spring (38) having a proximal and a distal end movably arranged within the chamber (18) over the valve actuating member (40).

2. The pressure actuated flow control valve and mechanism for an intravenous catheter assembly (10) as claimed in claim 1, wherein the valve stopper (36) has a distal and proximal face/end and an opening (50) running thoroughly therethrough.

3. The pressure actuated flow control valve and mechanism for an intravenous catheter assembly (10) as claimed in claim 1, wherein the valve (34) provided with one or more self-sealing slit(s) and/or hole(s) (52).

4. The pressure actuated flow control valve and mechanism for an intravenous catheter assembly (10) as claimed in claim 1, wherein the valve actuating member (40) has a distal and proximal end defining a passageway (44) for the needle (20) to pass therethrough, wherein the valve actuating member (40) has varying inner diameter in between the proximal and distal ends.

5. The pressure actuated flow control valve and mechanism for an intravenous catheter assembly (10) as claimed any one of the preceding claims, wherein the distal end of the spring (38) fixedly engaged with a first retaining member (46) provided at the proximal end of the valve stopper (36) and the proximal end of the spring (38) fixedly retained by a second retaining member (48) provided on the valve actuating member (40).

6. The pressure actuated flow control valve and mechanism for an intravenous catheter assembly (10) as claimed in any one of the preceding claims, wherein the spring (38) is arranged being retained between the first (46) and second (48) retaining member preventing the valve actuating member (40) from exposing out of the chamber (18) of the catheter hub (12).

7. The pressure actuated flow control valve and mechanism for an intravenous catheter assembly (10) as claimed in claim 1, wherein one or more hole and/or slit and/or perforation (30) provided at the distal end of the catheter hub (12).

8. The pressure actuated flow control valve and mechanism for an intravenous catheter assembly (10) as claimed in claim 1, wherein the spring (38) is arranged being in contact with an inner surface (42) of the chamber (18).

9. The pressure actuated flow control valve and mechanism for an intravenous catheter assembly (10) as claimed in claim 1, wherein the spring (38) is arranged without any contact with an inner surface (42) of the chamber (18).

10. The pressure actuated flow control valve and mechanism for an intravenous catheter assembly (10) as claimed in claim 1, wherein the catheter hub (12) provided with wings (32).

11. The pressure actuated flow control valve and mechanism for an intravenous catheter assembly (10) as claimed in claim 1, wherein the valve (34) comprises a dome portion (56) forming a distal face coupled with a lip portion or radial flange (58) extending in a direction opposite to an axial direction A, wherein the dome portion (56) has a curved profile and/or a semi-spherical profile forming the distal face.