DESC:
CROSS-REFERENCE TO THE RELATED APPLICATION

This application claims priority from Indian Patent Application No. 1380/KOL/2012 dated December 3, 2012, the entire disclosure of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to Blood collection sets. More particularly, the present invention relates to air venting mechanism in blood collection sets.

BACKGROUND OF THE INVENTION

Blood collection sets are generally known in the art. A typical blood collection set comprises a needle hub with a proximal end, a distal end and a passage extending between the said ends. The needle hub preferably includes two flexible wings that project transversely from the needle hub and can be held and taped in position against the patient’s skin when the blood collection set is in use. The needle hub is connected an IV cannula having a proximal end, a distal end terminating with a sharp tip and a lumen extending therethrough. The proximal end of the IV cannula is received in the distal end of the needle hub. A flexible plastic tube wherein a first end of the flexible plastic tube is connected to the proximal end of the needle hub. A second end of the flexible plastic tube is a female luer connector which receives a male luer connector when blood samples are not being collected. The second end of the flexible plastic tube is also adapted to receive blood collection container which may be vacuum sealed container.

Blood samples are collected by urging the IV cannula needle into the vein of the patient. The wings on the needle hub are taped against the patient’s skin to keep the IV cannula and needle hub of the blood collection set in position. The second end of the flexible plastic tube is connected to the blood collection container. The blood pressure is higher in the vein as compared to the air pressure in the blood collection container resulting in blood flow from vein to the interior of the blood collection container.

One of the primary disadvantages of the Blood collection sets without the air venting mechanisms is that the blood while flowing from the vein/artery to the blood collection container through the lumen of the IV cannula, passage of the needle hub and the flexible plastic tube creates a high pressure in the blood collection set resulting in offset in the pressure differential between the arterial/vein pressure and the pressure in the Blood collection set resulting in the reduction in the flow of blood from the vein/arteries of the patient into the blood collection chamber.

Medical practitioners have several approaches for addressing the problems relating to the air in the blood collection set. For example, the air in the blood collection set is displaced in the first blood collection chamber However, it should be noted that chemical solutions such as stabilizing agents, clotting agents etc are also placed in the blood collection container. A certain ratio of blood to chemical solutions is required to affect certain studies related to blood. The reduced volume of blood due to displacement of air in the blood collection container disturbs the ratio of the blood to the chemical solution present in the blood collection container leading to the wastage of blood as well as chemical solution. Moreover the blood collection container containing the reduced volume of blood has to discarded and replaced by another blood collection container. This adds to the cost and time of collecting the samples of the blood.

In order to address the problem of discarding the first blood collection container, the prior arts also suggest the presence of the air venting mechanism proximal to the second end of the flexible tube. Such venting mechanisms, although effective in venting the air from the Blood collection set results in an increased travel time by the blood to reach the blood collection chamber from the veins/arteries of the patient. Such increase in the travel time of the blood from the veins/arteries of the patient is due to venting of air at or near the second end of flexible tube. As a result, the reduced pressure differential between the venous/arterial pressure and the lumen of the IV cannula, passage of the needle hub and the flexible plastic tube of the Blood collection set after the inflow of the blood in the Blood collection set is maintained for a longer period of time. As a result, the travel time taken by the blood to reach the Blood collection chamber or reservoir from the veins/arteries of the patient is relatively more than that in the present invention. This may also lead to delayed indication of venous access and incorrect reading on the part of the medical practitioner that the targeted vein/artery was not accessed properly. In such a situation, the medical practitioner may try to access the vein again which causes discomfort to the patient and can be critical during emergency.

Accordingly, it is desired to provide a blood collection set with an air venting mechanism which overcomes the above discussed disadvantages. Further it is desired to provide a blood collection set which is inexpensive to manufacture, effective and simple in its construction and use.

SUMMARY OF THE INVENTION

A blood collection set comprising an IV needle hub, an IV cannula, a venting mechanism and flexible tube wherein the said IV hub comprises a proximal end, a distal end and a passage extending between the said ends, an IV needle cannula with a proximal end, a pointed distal end and a lumen extending between the ends wherein the proximal end of the said IV cannula is secured in the passage of the IV needle hub such that the lumen of the IV cannula is in communication with the passage of the IV hub, the said flexible tube includes opposite proximal and distal ends and a passage extending between the ends wherein the distal end of the tube is securely mounted to the proximal end of the IV hub so that the passage through the IV hub communicates with the passage through the tube, one or more venting mechanisms located on the said blood collection set.

In one embodiment the said air venting mechanism may located near the distal end of the IV hub. In another embodiment, the said air venting mechanism may be located near the proximal end of the IV hub. In yet another embodiment, flexible wings are mounted on the needle hub at a location near the distal end. In yet another embodiment, the said flexible wings can be folded into face-to-face relationship with one another for convenient gripping between a thumb and a forefinger. In yet another embodiment, the said IV needle cannula comprises a safety needle cover provided with slots to lockingly engage wings when the needle safety cover is in distal position to prevent re-exposure of the IV cannula after use. In yet another embodiment, a female luer fitting is securely mounted to proximal end of the tube. In yet another embodiment, the said female luer fitting is in communication with the blood container or a reservoir by means of a non patient needle assembly. In yet another embodiment, the non patient needle assembly includes a non patient hub and a non patient cannula wherein the non patient hub comprises a proximal end, a distal end and a passage extending between the said proximal and distal ends and the non patient cannula comprises a distal end securely mounted in the non patient hub, a proximal end projecting proximally from the non patient hub and a lumen that communicates with a passage through the non patient hub. A multiple sample sleeve may be mounted on over the non patient cannula and seamed to the proximal end of the non patient hub. In yet another embodiment, the said venting mechanism is provided between the proximal end of the needle hub and the distal end of the flexible tube .In yet another embodiment, the said air venting mechanism is integrally formed with the needle hub and is in communication with the passage of the needle hub. In yet another embodiment, the air venting mechanism is located near the distal section of the needle hub. In yet another embodiment, the air venting mechanism is located near the proximal section of the needle hub. In yet another embodiment, the air vent mechanism is located between the proximal end and the distal end of the flexible tube. In yet another embodiment, a plurality of air venting mechanism are located on the blood collection set. In yet another embodiment, one or more first air venting mechanism are located on the needle hub and one or more second air venting mechanisms are located near the proximal end of the said flexible tube. In yet another embodiment, one or more air venting mechanisms are located on the needle hub and one or more second venting mechanism are located on the female luer portion. In yet another embodiment, one or more first air venting mechanisms are located on the needle hub of the IV cannula and one or more second air venting mechanisms are located on the needle hub of the non patient cannula. In yet another embodiment, one or more first air venting mechanisms are located on the needle hub of the IV cannula and one or more second air venting mechanisms are located along the length of the flexible tube. In yet another embodiment, a first air venting mechanism is located on the needle hub of the IV cannula, a second air venting mechanism is located on the needle hub of the non patient cannula and a third air venting mechanism is located anywhere along the length of the flexible tube. In yet another embodiment, the said air venting mechanisms are provided by covering means such as a cap which may be open or close by the user/medical practitioner. In yet another embodiment, the said air venting mechanism may be unified with the said needle hubs. In yet another embodiment, air venting mechanism are made of materials or combination of materials which are permeable to air but are impermeable to the flow of the liquid such as fluid.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG 1A is a perspective view of the Blood collection device with an air venting mechanism

DEATILED DESCRIPTION OF THE INVENTION

The present invention relates to a Blood collection set with a self air venting mechanism that is permeable to air but impermeable to fluids such as blood.

The Blood collection set 10 includes an IV needle assembly 12 that comprises an IV needle hub 16. The IV needle hub 16 comprises a proximal end 18, a distal end 20 and a passage 22 extending between the ends 18, 20. The IV needle assembly 14 further comprises an IV needle cannula 24 with a proximal end 26, a pointed distal end 28 and a lumen 30 extending between the ends. The proximal end 26 of the IV cannula 24 is secured in the passage 22 of the IV needle hub 16 such that the lumen 30 of the IV cannula 24 is in communication with the passage 22 of the IV needle hub 16.

Flexible wings 32 may be mounted on the IV needle hub 16 at a location near the distal end 20. In one embodiment, the said wings 32 may be folded into face-to-face relationship with one another for convenient gripping between a thumb and a forefinger to enable manipulation of the IV needle assembly 14. In another embodiment, the wings 32 can also be rotated into a substantially coplanar distribution for taping the said wings to the skin of a patient.

The said IV needle assembly 14 may further include a needle safety cover which covers the pointed distal end 28 of the needle cannula 24. In one embodiment, the needle safety cover is provided with slots to lockingly engage wings when the needle safety cover is in distal position to prevent re-exposure of the IV cannula after use.

Blood collection set 10 further includes a length of flexible plastic tube 34. The said flexible plastic tube 34 includes opposite proximal 36 and distal ends 38 and a passage 40 extending between the ends 36, 38. The distal end 38 of the flexible plastic tube 34 is securely mounted to the proximal end 18 of the IV hub 16 so that the passage 22 through the IV hub 16 communicates with the passage 40 of flexible plastic tube 34. A female luer fitting 42 is securely mounted to proximal end 36 of the flexible plastic tube 34.

When the blood samples are not collected, the female luer fitting 42 may be connected to or closed by a male luer fitting 44. When the blood samples are collected, the female luer fitting 42 may be placed in communication with a reservoir or container 46 for collecting a sample of blood.

In one embodiment the female luer fitting 42 is directly in connection with the reservoir or container 46 for collecting a sample of blood.

In another embodiment, the female luer fitting 42 may be in communication with the blood container or a reservoir 46 by means of a non patient needle assembly 114 (not shown) commonly known in the art. Such non patient needle assembly includes a non patient hub 116 having a proximal end 118, a distal end 120 and a passage 122 extending between the said proximal and distal ends 118, 120. The non patient needle assembly 114 may further include a non patient cannula 124 having a distal end 128 securely mounted in the non patient hub 116, a proximal end 126 projecting proximally from the non patient hub 116 and a lumen 130 that communicates with a passage 122 through the non patient hub 116.

A multiple sample sleeve may be mounted on over the non patient cannula 124 and seamed to the proximal end 118 of the non patient hub 116. External portions of the non patient hub 116 near the proximal end 118 thereof may be formed with an array of external threads or other mounting structures to enable the non patient needle assembly 114 to be mounted to a collection tube holder or other such medical devices.

The blood from the arteries/veins of the patient may be collected by the Blood collection set 10 by folding the said flexible wings 32 into face-to-face engagement with one another and gripping wings 32 between a thumb and a forefinger. Any packaging cover that may be mounted over the IV cannula is then removed and discarded. Pointed distal end 28 of the IV cannula is then urged into the targeted blood vessel and the wings 32 may be taped into face-to-face engagement with the skin of the patient.

Blood collection set 10 will include a plurality of internal spaces that will initially be at ambient air pressure. These internal spaces may include lumen 30 through the IV cannula 24, the passage 22 through the IV hub 16, the passage 40 through the flexible tube 34, passage 122 through the non patient hub 116 and lumen 130 through non patient cannula 124.

The venous or arterial access achieved by the IV cannula 24 of the Blood collection set places the above identified internal spaces 22, 30, 40, 122, 130 of Blood collection set 10 in communication with the pressure of the blood in the patient i.e. the arterial/venous pressure. The arterial/venous pressure is greater than the ambient air pressure. As a result, the blood will begin to flow from the arteries/veins into the above identified internal spaces. However, the flow of the blood in blood collection set 10 will decrease the volume of the air in the internal spaces of the Blood collection set 10 resulting in the increase the air pressure in the internal spaces of the Blood collection set 10.

As a result, the air pressure in some portions of the internal spaces 22, 30, 40, 122, 130 of the blood collection set will be substantially equal to the venous or the arterial pressures. Normally, this high pressure air is made to escape into the reservoir or container 46 that is placed in the communication with the non patient needle 124 which results in the collection of less blood than required in the Blood collection container or reservoir 46. Hence the first Blood collection container or reservoir 46 with the prior art system is normally a discard tube which results in the wastage of blood.

The prior art also provides for air venting mechanisms 12 located near the proximal end 36 of the flexible tube 34 or located on the needle hub 116 of the non patient IV needle assembly 14 to vent the air in the above identified internal spaces 22, 30, 40, 122, 130 . However, such venting mechanisms 12, although effective in venting the air from the above mentioned internal spaces 22, 30, 40, 122, 130 results in an increased travel time by the blood to reach the blood collection container/reservoir 46 from the veins/arteries of the patient. Such increase in the travel time of the blood from the veins/arteries of the patient is due to venting of air at or near the proximal end 36 of the flexible tube 34. As a result, the reduced pressure differential between the venous/arterial pressure and the internal spaces 22, 30, 40, 122, 130 of the Blood collection set 10 after the inflow of the blood in the Blood collection set 10 is maintained for a longer period of time. As a result, the travel time taken by the blood to reach the Blood collection container or reservoir 46 from the veins/arteries of the patient is relatively more than that in the present invention.

As the blood travel time taken by the blood to reach the Blood collection container or reservoir 46 from the veins/arteries of the patient is relatively more in the prior art Blood collection devices , the time to check if successful vein/artery penetration is achieved is delayed. This leads to delayed indication of venous/arterial access and incorrect reading on the part of the medical practitioner that the targeted vein was not accessed properly. In such a situation, the medical practitioner may try to access the vein again which causes discomfort to the patient and can be critical during emergency.

The present invention aims to overcome the disadvantages in the prior art by venting the air in the blood collection set 10 by means of the air venting mechanism 12 such that the travel time travel time taken by the blood to reach the Blood collection container or reservoir 46 from the veins/arteries of the patient may be significantly reduced.

The air venting mechanism 12 in the present invention is provided at the location where the air in the internal space 30, 22 of the IV cannula 24 and the IV needle hub 16 are vented at an early stage such that the pressure differential between the arterial/venous pressure and the internal spaces 30, 22 of the IV cannula 24 and IV needle hub 16 increases. As a result, the travel time taken by the blood to reach the Blood collection container or reservoir 46 from the veins/arteries of the patient is relatively less than that in the prior art. In one embodiment of the present invention, the air venting mechanism 12 is an independent unit which may be connected/assembled/fixed in the blood collection set 10. In one embodiment, the said venting mechanism is provided between the proximal end 18 of the needle hub 16 and the distal end 38 of the flexible tube 34 to vent the air present in the internal spaces 30, 22 of the IV cannula 24 and IV hub 16. The said air venting mechanism 12 comprises feature or elements which are permeable to the air but impermeable to fluids such as Blood.

The said air venting mechanism 12 may also be integrally formed with the needle hub 16 and is in communication with the passage of the needle hub 16. In one embodiment, the said air venting mechanism 12 is located near the proximal end 18 of the needle hub 16. In another embodiment, the air venting mechanism 12 may be located near the distal end 20 of the needle hub 16 and is in communication with the passage of the needle hub 16. In yet another embodiment, the air vent mechanism 12 may be located between the proximal end 36 and the distal end 38 of the flexible tube 34. The said air venting mechanism 12 comprises features or elements which are permeable to air but are impermeable to fluid such as Blood. The said air venting mechanism 12 may also be covered with a cap which may be open or close by the user/medical practitioner.

A plurality of air venting mechanism 12 may also be located on the blood collection set 10. In one embodiment, one or more first air venting mechanism 112 are located on the needle hub 16 and one or more second air venting mechanisms 212 are located near the proximal end 36 of the flexible tube 34. In another embodiment, one or more air venting mechanisms 112 are located on the needle hub 16 and one or more second venting mechanisms 212 are located on the female luer portion 42. In yet another embodiment, one or more first air venting mechanisms 112 are located on the needle hub 16 of the IV needle assembly 14 and one or more second air venting mechanisms 212 are located on the needle hub 116 of the non patient needle assembly 114. In yet another embodiment, one or more first air venting mechanisms 112 are located on the needle hub 16 of the IV needle assembly 14 and one or more second air venting mechanisms 212 are located along the length of the flexible tube 34. In yet another embodiment, one or more first air venting mechanisms 112 are located on the needle hub 16 of the IV needle assembly 14, one or more second air venting mechanisms 212 are located on the needle hub 116 of the non patient needle assembly 114 and one or more third air venting mechanisms 312 may be located anywhere along the length of the flexible tube 34 . The said first 112, second 212 and the third 312 air venting mechanisms comprises features or elements which are permeable to air but are impermeable to fluid such as Blood. The said first 112, second 212 and the third 312 air venting mechanisms may covering means such as a cap be covered with a cap which may be open or close by the user/medical practitioner. A plurality of air vent mechanism in the Blood collection set 10 ensures the venting of the air in internal spaces 22, 30, 40, 122, 130 of the Blood collection set 10.

The said air venting mechanisms located on the IV needle hub 16 of the IV needle assembly 14 and/or the needle hub 116 of the non patient needle assembly 114 may be unified with the needle hubs i.e. at least a portion of which is made from a feature or element which is permeable to the air but impermeable to the fluids such as blood.

Venting mechanism in the present invention comprises features or elements which may facilitate the venting of air but prevents the flow of the liquid such as fluid. The said features of the venting mechanism may allow one way flow of the air i.e. the flow of the air from the internal spaces of the Blood collection set to the surroundings but prevent the flow of the air from the surrounding into the Blood collection set. The features or elements of the venting mechanism in the present invention, being not limited to, may include, for example, either or a combination of

• a porous plug formed from a matrix or carrier material, typically hydrophobic, that is coated with, impregnated with, or otherwise contains a hydrophilic material that swells on contact with aqueous or water containing substances. This swellable nature thereby provides the scaling function in the vent upon contact with blood;
• an air vent provided through a matte finish, micro-sized channels, laser drilled holes, tortuous path, or a vent provided between sealing surfaces, e.g., in a cord in which the holes, gaps or channels arc large enough to permit airflow but small enough to prevent, blood leakage;
• a porous plug that becomes sealed upon contact with blood using biological phenomena, eg., by clotting and/or cell agglutination that blocks the vent;
• a superabsorbant material to seal the vent by swelling on contact, with a aqueous fluid; or
• a one-way valve, e.g., a thin flap such as plastic film covering a vent, a deformable seal such as a rubber or plastic duckbill valve, or a deformable wrap over a vent.

Typically, a porous plug is formed from a hydrophobic material, such as high-density polyethylene (IIDPE), which is coated with, impregnated with, of otherwise contains a hydrophilic material such as carboxymethylcellulose (CMC) or a polyacrylate. Alternative hydrophobic materials include but are not limited to polytetrafluoroethylene (PTFE), ultra-high molecular weight polyethylene (IJIIMWPII), Nylon 6, polypropylene (PP), polyvinylidine fluoride (PVDF) or polyethersulfone (PES).

An embodiment of the venting mechanism may also comprise micro-sized holes formed in an exterior wall. The holes are large enough to permit airflow but small enough to prevent blood leakage. The holes of the venting mechanism may be any number including a single hole although multiple holes arc typical for a more reliable function. The holes may be laser-drilled, meaning that they may be burned through the wall or substrate using one or more laser beams. The substrate may be any convenient material although thin plastic or plastic film is typical. The vent mechanism may include a one-way valve as previously described. The vent mechanism may be located at any convenient space along the fluid passage in the flexible tube, luer or non-patient hub or in an added component although location at the proximal end is typical to provide flash along the full length of the tube

A porous plug that becomes sealed upon contact with blood using biological phenomena may use, for example, a porous material such as a sintered plastic, ceramic or metal, or a breathable cord, or by locating the biological agent in small holes or spaces between parts. The vent, may be of any convenient shape. The venting may be at any location or locations along the fluid passage, but is preferably at the proximal end such as at the hub near the collection device. The vent is typically made from contains, is adjacent to, or works in collaboration with, a stimulant that interacts with blood to promote clotting and/or cell agglutination such that the clot and/or clumped cells block ongoing flow of blood through the vent. An example a clotting stimulant is silica or crushed glass, or fiberglass. An example of an agglutinizing agent is lectin. An example of a platelet activator is collagen or thrombin. A neutralizer for anti-coagulant such as protomine sulfate may be included the biological stimulant may be applied using any convenient process including as a powder, a solution, a suspension, a slurry, or any other form. It may be dried or lyophilized.

Although this invention has been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. Thus, from the foregoing description, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit or scope of the invention as set forth herein.

Accordingly, it is not intended that the scope of the foregoing description be limited to the exact description set forth above, but rather that such description be construed as encompassing all of the features of patentable novelty that reside in the present invention, including all the features and embodiments that would be treated as equivalents thereof by those skilled in the relevant art. Thus, it is intended that the scope of the present invention herein disclosed should not be limited by the particular disclosed embodiments described above but should be determined only by a fair reading of the claims appended hereinafter.

List of Reference Numerals
10 Blood collection set
12 Venting Mechanisms
14 IV needle assembly
16 IV needle hub
18 Proximal end of the IV needle hub
20 Distal end of the IV needle hub
22 Passage of the IV needle hub
24 IV needle cannula
26 Proximal end of the IV needle cannula
28 Distal end of the IV needle cannula
30 lumen of the IV needle cannula
32 Flexible wings
34 Flexible Plastic tube
36 Proximal end of the Flexible Plastic Tube
38 Distal end of the Flexible Plastic tube
40 Passage of the Flexible Plastic tube
42 Female Luer Fitting
44 Male Luer Fitting
46 Reservoir/Container
112 First Air Venting Mechanisms
114 Non patient IV Needle Assembly
116 Non patient IV Needle Hub
118 Proximal end of the Non patient IV Needle Hub
120 Distal end of the Non patient IV Needle Hub
122 Passage of the Non patient IV Needle Hub
124 Non patient IV needle cannula
126 Proximal end of the Non Patient IV needle cannula
128 Distal end of the Non Patient IV needle cannula
130 Lumen of Non Patient IV needle cannula
212 Second Air Venting Mechanisms
312 Third Air Venting Mechanisms
,CLAIMS:
1. A blood collection set (10) comprising an IV needle hub (16), an IV cannula (24), an air venting mechanism (12) and flexible tube (34) wherein:

the said IV hub (16) comprises a proximal end (18), a distal end (20) and a passage (22) extending between the said ends (18, 20);
an IV needle cannula (24) with a proximal end (26), a pointed distal end (28) and a lumen (30) extending between the ends (26, 28) wherein the proximal end (26) of the said IV cannula (24) is secured in the passage (22) of the IV needle hub (16) such that the lumen (30) of the IV cannula (24) is in communication with the passage (22) of the IV hub (16);
the said flexible tube (34) includes opposite proximal (36) and distal ends (38) and a passage (40) extending between the ends (36,38) wherein the distal end (38) of the said flexible tube (34) is securely mounted to the proximal end (18) of the IV hub (16) so that the passage (22) through the IV hub (16) communicates with the passage (40) through the said flexible tube (34); and
one or more venting mechanisms (12) located on the Blood collection set (10).

2. A blood collection set (10) as claimed in claim 1, wherein the air venting mechanism (12) is located near the distal end (20) of the IV hub (16).

3. A blood collection set (10) as claimed in claim 1, wherein the said air venting mechanism (12) is located near the proximal end (18) of the IV hub (16).

4. A blood collection set (10) as claimed in claim 1, wherein the said flexible wings (32) are mounted on the needle hub (16) at a location near the distal end (20).

5. A blood collection set (10) as claimed in claim 4, wherein the said flexible wings (32) can be folded into face-to-face relationship with one another for convenient gripping between a thumb and a forefinger.

6. A blood collection set (10) as claimed in claim 1, wherein the said IV needle cannula (24) comprises a safety needle cover provided with slots to lockingly engage wings (32) when the needle safety cover is in distal position to prevent re-exposure of the IV cannula after use.

7. A blood collection set (10) as claimed in claim 1, wherein a female luer fitting (42) is securely mounted to proximal end (36) of the said flexible tube (34).

8. A blood collection set (10) as claimed in claim 7, wherein female luer fitting (42) is in communication with the blood container or a reservoir (46) by means of a non patient needle assembly (114).

9. A blood collection set (10) as claimed in claim 8, wherein the non patient needle assembly (114) includes a non patient hub (116) and a non patient cannula (124) wherein:
the non patient hub (116) comprises a proximal end (118), a distal end (120) and a passage (122) extending between the said proximal and distal ends (118,120); and the non patient cannula (124) comprises a distal end (128) securely mounted in the non patient hub (116), a proximal end (126) projecting proximally from the non patient hub (116) and a lumen (130) that communicates with a passage (122) through the non patient hub (116).

10. A blood collection device (10) as claimed in claim 9, wherein a multiple sample sleeve may be mounted on over the non patient cannula (124) and seamed to the proximal end (118) of the non patient hub (116).

11. A blood collection device (10) as claimed in claim 1, wherein the said venting mechanism (12) is provided between the proximal end (18) of the needle hub (16) and the distal end (38) of the flexible tube (34).

12. A blood collection device (10) as claimed in claim 1, wherein the said air venting mechanism (12) is integrally formed with the needle hub (16) and is in communication with the passage (22) of the needle hub (16).

13. A blood collection device (10) as claimed in claim 1, wherein the air venting mechanism (12) is located between the proximal end (36) and the distal end (38) of the flexible tube (34).

14. A blood collection device (10) as claimed in claim 1, wherein a plurality of air venting mechanism (12) are located on the blood collection set (10).

15. A blood collection device (10) as claimed in claim 16, wherein one or more first air venting mechanism (112) are located on the needle hub (16) and one or more second air venting mechanisms (212) are located near the proximal end (36) of the said flexible tube (34).

16. A blood collection device as claimed in claim 16, wherein one or more air venting mechanisms (112) are located on the needle hub (16) and one or more second venting mechanisms (212) are located on the female luer portion 42).

17. A blood collection device (10) as claimed in claim 16, wherein one or more first air venting mechanisms (112) are located on the needle hub (16) of the IV needle assembly (14) and one or more second air venting mechanisms (212) are located on the needle hub (116) of the non patient needle assembly (114)..

18. A blood collection device (10) as claimed in claim 16, wherein one or more first air venting mechanisms (112) are located on the needle hub (16) of the IV needle assembly (14) and one or more second air venting mechanisms (212) are located along the length of the flexible tube (34).

19. A blood collection device (10) as claimed in claim 16, wherein a first air venting mechanism (112) is located on needle hub (16) of the IV needle assembly (14), a second air venting mechanism (212) is located on the needle hub (116) of the non patient needle assembly (114) and a third air venting mechanism (312) is located anywhere along the length of the flexible tube (34).

20. A blood collection device (10) as claimed in claim 1, wherein the said air venting mechanisms (12) are provided by covering means such as a cap which may be open or close by the user/medical practitioner.

21. A blood collection device (10) as claimed in claim 1, wherein the said air venting mechanism (12) may be unified with the said needle hubs (16,116).

22. A blood collection device (10) as claimed in claim 1, wherein air venting mechanism (12,112,212,312) are made of materials or combination of materials which are permeable to air but are impermeable to the flow of the fluids such as blood.