PHLEBOTOMY DEVICE
FIELD OF THE INVENTION
THIS INVENTION relates to a safety phlebotomy device and to a method of assembling the device.
BACKGROUND OF THE INVENTION
Potentially lethal infections such as human immune deficiency virus (HIV), hepatitis B, or the like, can be transferred by needle sticks from needles of used phlebotomy devices. The risk of needle sticks extends to medical practitioners, persons responsible for handling phlebotomy devices after use, and the like. The risk of needle sticks is increased by the practice of bending axially disposed needles of phlebotomy devices, to allow penetration of a patients skin at acute angles, the practice of having to fit a phlebotomy needle on a barrel, the practice of fitting caps on phlebotomy needles, etc.
SUMMARY OF THE INVENTION
According to the invention there is provided a phlebotomy device, which includes: a body defining vial receiving means into which a fluid collection vial can be received;
a needle, secured to the body, and having a front section extending from the front end of the body and a rear section protruding into the vial receiving means; and a needle shield displaceably mounted on the body to shield the needle at least in part and being displaceable along the body to vary the length of an unshielded part of the needle protruding from the needle shield, wherein the device further includes disposal locking means for non- releasably locking the needle shield relative to the body in a disposal position in which the point of the needle is shielded by the needle shield, the disposal locking means including at least one disposal locking formation on the body for engaging the needle shield non-releasably to lock the needle shield in the disposal position, relative to the body.
The body may be in the form of a holder having a front end, and defining vial receiving means in the form of a rear cavity into which the fluid collection vial can be inserted, the rear section of the needle protruding into the cavity.
The disposal locking formation may preferably protrude downwardly from the outer surface of the holder. Alternatively, the disposal locking formation may protrude from an inside of a guide channel, defined in the holder, in which the needle shield is slideably receivable. The protuberance may be a barb.
The needle shield may include engaging means, engageable with the disposal locking formation on the holder to lock the needle shield non-releasably in the disposal position. The engaging means on the needle shield may include a recess defined in the needle shield, into which the disposal locking formation extends when the needle shield is in its disposal position. Alternatively, the engaging means may include a rearwardly facing surface defined on the needle shield, against which the locking formation abuts when the needle shield is in its disposal position.
The disposal locking formation may increase in size from its rear end to its front end. Preferably, the front end of the locking formation may define a locking face, and its rear end may define an upwardly tapering incline so as to provide a fairlead for the engaging means to climb before engaging lockingly with the locking face, when the needle shield is in its disposal position. Thus the disposal locking formation may be a tapered ramp.
Preferably, two disposal locking formations are provided on the holder.
The needle shield may include at least one wing having a rearwardly facing surface against which the disposal locking formation can abut, or alternatively within which the recess, into which the disposal locking formation is receivable, is defined. The wing preferably also defines a
forwardly extending channel which can slide over the disposal locking formation with a relieved fit, while the needle shield is in a storage or an operative position, thereby protecting the locking formation from damage prior to being brought into locking engagement with the wing.
Preferably two channels are provided.
The device may also include storage locking means for releasably locking the needle shield in a storage position in which the point of the needle is shielded by the needle shield.
The storage locking means may include a storage locking formation on the holder and spaced rearwardly from the disposal locking formation. The storage locking formation may preferably be a protuberance extending downwardly from the outer surface of the holder or may extend from an inside of a guide channel, comprising mounting means defined on the holder, along which the needle shield may be slideably displaceable. The storage locking formation may preferably protrude from the holder by less than the disposal locking formation. In the storage position, the storage locking formation may be releasably engageable with the engaging means of the needle shield, when the needle shield is in the storage position. Thus the storage locking formation locates against the rearwardly facing face of the needle shield or within the recess of the needle shield in the storage position. The storage locking formation may preferably have a height of, at most, half
of the height of the disposal locking formation. Thus the needle shield can ride back and forth over the storage locking formation.
Alternatively, or in addition, the storage locking formation may include a formation on the needle shield, disposed for frictional releasable engagement with the needle, releasably to lock the needle shield in its storage position.
The device may include operative position locking means for releasably locking the needle shield in an operative position in which the needle protrudes from the needle shield. The operative position locking means may include at least one surface defined on the needle shield, which is biased against the holder, to abut the holder frictionally and create a friction lock between the needle shield and the holder. The surfaces may include a surface of the wings which may abut the outer surface of the holder, and a surface of a tab, which abuts the inner surface of the holder.
Alternatively, or in addition, the operative position locking means may include an enlargement or swollen zone on a guide rail of the needle shield, for frictionally engaging a complemental guide channel defined on the holder. It will be appreciated that the guide channel could be located on the needle shield and the guide rail on the holder.
In the preferred form of the invention the holder may define a longitudinally extending slot, defining a guide channel for receiving a longitudinally extending guide rail extending from the needle shield. The slot may be in the form of a slideway. The rear end of the guide channel may preferably define an enlarged zone through which a tab disposed at the rear end of the needle shield, can enter the holder.
The needle shield in the preferred form of the invention may also include a slide, which preferably extends longitudinally only along part of the length of needle shield and is spaced from the rear end of the needle shield. The slide may be discontinuous.
The scope of the invention extends separately to the needle shield described above.
The slide may be receivable in a slideway defined in the holder in a manner preferably carried out by the steps of:
Introducing the rear end of the slide of the needle shield into the front end of the slideway of the holder; moving the slide further into the slideway, with part of the needle shield being inclined relative to the holder so that the engaging formations on the needle shield clear the locking means on the holder, until the tab is in register with the enlarged zone of the slideway;
pressing the rear end of the needle shield against the holder to cause the tab to enter the holder through the enlarged zone at the rear end of the guide channel, preferably in non-releasable click-fit engagement.
The needle may preferably be a cranked needle, having a cranked section extending between the front and rear sections of the needle. The holder may include securing formations for securing the cranked section of the needle to the holder. The securing formations may include one or more clips extending from a bulkhead of the holder.
In addition, or alternatively, the securing formation may include a cylindrical protuberance extending rearwardly from the bulkhead, between which cylindrical protuberance and the bulkhead, the cranked section of the needle may be secured. The cylindrical protuberance may define a longitudinally extending slot with an adjacent securing protuberance in the form of a rail or flap, which can be deformed to close the slot once the needle has been inserted into the slot. Thus, when assembling the device, the front point of the needle is preferably introduced through the rear end of the holder into the needle shield. The needle may then be pushed further into the needle shield after deformation of the protuberance, until the cranked portion of the needle passes into the slot of the cylindrical projection and engages the clip on the bulkhead. The rail or flap adjacent the slot may then be heated and deformed to weld the slot closed.
The device may include a flexible protective teat, typically formed of silicone rubber, to cover part of the rear section of the needle, protruding into the cavity.
The teat may define a bore with a neck, which, by virtue of an interference fit between the neck and the needle, may form a seal between the neck and the needle, the remainder of the bore of the teat fitting on the needle with a loose fit, so that the remainder of the teat can be displaced along the needle, by a fluid collection vial, when received in the cavity.
The teat may include teat retention means, which may include neck compression means, for retaining the teat in position on the needle relative to the holder. The neck compression means may include a neck containment formation, defined on the holder which may include a cylindrical protuberance extending rearwardly from the bulkhead, in which the neck is receivable with a press fit.
The teat may be introduced to extend over the rear point of the needle, and into the cylindrical projection with a press fit. The needle shield may then be displaced along the holder to the storage position prior to sterilisation and packaging of the device.
The front end of the needle may preferably have a bevelled point which faces upwardly towards the axis of the barrel, so that the bevel
will in use face upwardly relative to the surface of a patient's skin, to prevent venous trauma when the point is introduced into a vein.
The scope of the invention extends separately to a method of assembling the phlebotomy device as described above.
The body may be in the form of an adapter, configured to receive a holder in holder receiving means, the holder defining vial receiving means in the form of a rear cavity into which the fluid collection vial can be inserted, wherein the adapter includes securing means for securing the holder to the body, and the rear section of the needle extends rearwardly from the body, towards the holder receiving means.
The holder receiving means may include clasps for clasping the holder. In addition, or alternatively, the holder receiving means may include a clip for clipping the adapter to the holder, or a clip receiving formation, for receiving a clip on the holder, to clip the holder to the adapter.
The adapter may include a bulkhead defining a recess for receiving a head of a teat, which teat may cover the rear section of the needle. Preferably the head of the teat may include a flange, which fits within the recess with a press fit. The teat may include a neck adjacent the flange, which neck fits, in use, with a press fit, inside a spigot of the holder located in the adapter, with the free end of the spigot abutting the flange of the teat.
The scope of the invention extends separately to the teat described above.
In an alternative form of the invention, the adapter may have a bulkhead with a rearwardly extending cylindrical formation through which the rear section of the needle may project, the rearwardly projecting cylindrical formation defining a needle teat receiving formation for a neck of a teat, which teat covers the rear section of the needle.
The holder for this alternative form of the invention may include a front wall defining an aperture through which the cylindrical formation can extend when the holder is secured to the adapter. Preferably the external diameter of the cylindrical formation is just less than the internal diameter of the aperture, so that the cylindrical formation fits within the aperture with a comfort fit. The holder may preferably include a clip or protuberance on its outer surface, for engaging a complementary clip or protuberance receiving formation on the adapter.
The scope of the invention extends separately to the holder described above.
The disposal locking formation may include at least one laterally biased detent, defined on the needle shield, which can expand
resiliency in a clipping fashion, if the detent extends forwardly of a front end of the body.
The invention will now be described by way of non-limiting example, with reference to the accompanying diagrammatic drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 shows a perspective view of the underside of a safety phlebotomy device in accordance with a first embodiment of the invention in a non-releasably locked disposal position;
Figure 2 shows a perspective view of the underside of the phlebotomy device of Figure 1 in the releasably locked storage position;
Figures 3 shows a cross-sectional view of a conventional vacuum vial used in association with the phlebotomy device of Figures 1 and 2 in the collection of blood samples;
Figures 4A, 4B and 4C show respectively, a perspective underside view of the vacuum vial holder, a perspective underside view of the needle shield, and a perspective top view of the needle shield, of the phlebotomy device of Figure 1 ;
Figure 5 shows a cross-section end view of the tongue of the holder of Figure 4A, taken at V-V;
Figure 6 shows a detail perspective view of an alternative to the needle shield of Figure 4B;
Figure 7 shows a cross-sectional side view of the phlebotomy device of Figure 1 , taken at VII-VII;
Figure 8 shows a cross-sectional side view of the teat neck containment formation of the phlebotomy device of Figure 7;
Figures 9A and 9B show respectively, end views of the phlebotomy device of Figure 7, of the teat neck containment formation of Figure 8 before and after over-welding of the needle securing formation shown thereon;
Figures 10A, 10B and 10C show respectively, detailed cross-sectional side views of the needle and shield in their unshielded, fully retracted positions, their intermediate, unshielded positions; and their non-releasably, locked disposal positions;
Figures 11A and 11B show respectively, three-dimensional front and rear exploded views of an adapter in accordance with a second embodiment of the invention, prior to being mounted on a conventional vacuum vial holder;
Figure 12 shows a detailed, three-dimensional front view of the rubber teat of the adapter of Figure 11 ;
Figures 13A and 13B show respectively, three-dimensional front and rear assembled views of the adapter of Figure 11 after being mounted on a conventional vacuum vial holder;
Figure 14 shows an exploded, three-dimensional rear view of a safety phlebotomy assembly in accordance with a third embodiment of the invention, including an alternative adapter and a proprietary (non- conventional) vacuum vial holder;
Figure 15 shows an assembled, three-dimensional front view of the safety phlebotomy assembly of Figure 14;
Figures 16A, 16B and 16C show side views, respectively, of the phlebotomy device of Figure 1 , to illustrate the three main steps in the method of assembly of the device;
Figure 17 shows a detailed rear end and underside three-dimensional view of the safety phlebotomy device of Figure 1 , amplifying the assembly step of Figure 16C;
Figure 18A shows a detailed, three-dimensional underside view of the rear end of the needle shield of Figure 4B;
Figure 18B shows a detailed cross-sectional view of the needle shield of Figure 18A, taken at XVIIB-XVIIB;
Figure 19 shows a detailed three-dimensional underside view of the locking formation of the holder of Figure 4A;
Figure 20A shows a detailed three-dimensional underside view of the rear end of the needle shield of Figure 6;
Figure 21 shows an under plan view of a safety phlebotomy device in accordance with a fourth embodiment of the invention;
Figure 22 shows a cross-sectional plan view of the safety phlebotomy device of Figure 21;
Figure 23 shows an under plan view of a safety phlebotomy device in accordance with a fifth embodiment of the invention;
Figure 24 shows a detail view of part of the phlebotomy device of Figure 23;
Figure 25 shows an under plan view of the phlebotomy device of Figure 23, with the needle shield in the disposal position;
Figure 26 shows a three-dimensional view of part of the phlebotomy device of Figures 23 to 25; and
Figure 27 shows a three-dimensional view of an alternative embodiment of the needle shield and the slideway of the safety phlebotomy device of Figure 26.
DETAILED DESCRIPTION OF THE DRAWINGS
Referring firstly to Figures 1 to 10, and 16 to 20 of the drawings, a phlebotomy device 10 includes a vacuum vial holder 12, a needle 14 and a needle shield 16.
The holder 12 is injection moulded from polypropylene and has a slideway 18 for the needle shield 16. The holder 12 is closed at its front end by way of a bulkhead 20 and has a cavity or opening 22 at its rear end into which a conventional vacuum vial 24, having a rubber stopper 25 with a pierceable, self re-sealing diaphragm 27, may be inserted in order to collect blood samples. The bulkhead 20 of the holder 12 has a forwardly extending projection or tongue 26.
The needle 14 is cranked and consists of an exterior, front section or portion 28, a cranked section or radially extending portion 30 and a
rear section or an interior portion 32. The exterior portion 28 terminates in a point 34, and likewise the interior portion 32 terminates in a point 36. The needle is arranged so that the bevel of the exterior point 34 is disposed upwardly relative to the skin of the patient during insertion of the point, so as to minimise the risk of venous trauma at this stage of the phlebotomy procedure.
The cranked portion of the needle 14 is held within clips 38 against the bulkhead 20. Part of the interior portion 32 of the needle 14 abuts a cylindrical protuberance or projection 40 extending rearwardly from the bulkhead 20 to define a needle teat containment formation. The projection 40 defines a groove or axial slot 42 with a flared opening 44 for locating the needle 14 in position. The projection 40 further defines a chamber 46 within which the head 48 of a needle teat 50 is introduced in a compression push fit so as to retain the teat 50 in position relative to the holder 12, and at the same time to reinforce sealing integrity between the head 48 and the needle 32.
The needle shield 16 is injection moulded from polyacetal. The needle shield has a thumb grip 52, a guide rail 54, an assembly locking tab 56, two locking formations or wings 58, each defining a forwardly extending containment channel 60, a slide 62, and grooves 64.1 to 64.3 for the needle 14. Each containment channel 60 is provided at its rear end with a backwardly angled ramp or fairlead 61, illustrated in further detail in Figures
18A and 18B. It can be seen from Figures 4B and 4C that the grooves 64.1 to 64.3 for the needle 14 are discontinuous. The discontinuity of the grooves 64 means that the needle shield 16 can be inexpensively moulded using a simple two piece mould, without the necessity of pulling any cores.
The needle shield 16 can be slid between a storage position as shown in Figure 2 and an unshielded fully retracted position as shown in Figure 10A. The position of the needle shield 16 is infinitely variable between the storage and unshielded fully retracted positions. One such intermediate position is shown in Figure 10B.
In the storage position, the point 34 of the needle 14 is shielded by the needle shield 16. As the needle shield 16 is retracted from the storage position, so the length of the unshielded portion of the needle 14 increases. The length of the unshielded portion of the needle 14 can thus be set to a desired length to suit a particular patient.
As illustrated in Figure 6, the groove 64.3 of the needle shield 16 contains a stop formation defined by a raised zone 66 which, as shown in Figures 7 and 10C, rearwardly abuts a bend 68 in the needle 14 when the needle shield 16 is in its non-releasably locked position. The groove 64.3 also includes a needle engaging formation defined by a constricted zone 70 which contains the bend 68 in the needle 14 in a releasable friction lock in the storage position, thereby suppressing inadvertent backward displacement of
the needle shield 16 prior to the phlebotomy device 10 being brought into use.
Figure 6 also illustrates an alternative to the locking means provided by the rear edges 76 of locking wings 58, defined as two blind locking recesses 72 adjacent the rear ends of containment channels 60.1. As illustrated in further detail in Figures 20A, 20B and 20C, each locking recess 72 is provided at its front end with a locking face 76.1 and each containment channel 60.1 is provided at its rear end with a backwardly angled ramp or fairlead 61.1.
Between the unshielded, fully retracted position and the storage position, the locking wings 58, which are nominally resilient, are biased against the external underside of the holder 12. The assembly locking tab 56 is biased against the internal underside wall of the holder 12. In combination, this creates a friction lock between the needle shield 16 and the holder 12. This friction lock may be further reinforced by providing a swollen zone (not illustrated) over a portion of the guide rail 54 which creates friction between the sides of the guide rail 54 and the sides of the guide channel 74 defined in the holder 12. Together, these arrangements ensure that when the needle shield 16 is set in a desired position, it will remain in that position until sufficient force is applied to the needle shield 16 to overcome the friction lock thereby constituted.
Reference to Figure 2, read in conjunction with Figures 18 and 19 will show how, in the storage position, the needle shield 16 is forwardly displaced along the holder until the fairleads or ramps 61 at the rear of the containment channels 60 are pushed over and beyond a storage locking formation consisting or a pair of retaining nibs 78 formed on the underside of the holder 12. Both the rear and the front of the nibs 78 define a complemental angle to the ramps 61, to allow the rear edges 76 of locking wings 58 to slide releasably over the nibs 78 in either direction. The containment channels 60 defined in the locking wings 58 slide in a comfort fit along and over channel guides 80 defined on the holder 12, and in the storage position the channels 60 are located in a relieved fit over locking barbs 82, whose front ends define locking faces 83, and whose rear ends 85 define a complemental angle to ramps 61. The barbs 82 are thereby protected within the channels 60 from damage until they are brought into locking engagement with the rear edges 76 of locking wings 58. This is achieved by urging ramps 61 up and over the inclined rear ends 85 of the barbs 82 until rear edges 76 of locking wings 58 drop into locking engagement with the locking faces 83 of the barbs, as illustrated in Figure 1. The needle shield 16 cannot be retracted from this position without breaking off the locking barbs 82. The needle shield 16 is thus for practical purposes non-releasably locked in the disposal position. As in the storage position, the point 34 of the needle 14 is shielded by the needle shield 16 when the needle shield 16 is in its disposal position. The phlebotomy device 10 can thus be
disposed of with the needle shield 16 in its disposal position without fear of someone being pricked by the point 34 of the needle 14.
From an examination of Figure 6, it will be apparent that the procedure described in the previous paragraph will apply equally to the alternative locking arrangement provided by the locking faces 76.1 of the two blind locking recesses 72 in substitution for the rear edges 76 of the locking wings 58. In this alternative case, taken in relation to Figure 2 (illustrating the storage position) both the storage retaining nibs 78 and the disposal locking barbs 82 will be concealed in the locking recesses 72 and the containment channels 60.1 respectively. In the case of Figure 1 (illustrating the disposal position) the locking barbs 82 will be concealed in the locking recesses 72, with only the retaining nibs 78 visible behind the rear edges 76 of the locking wings 58.
Reference to Figure 7 will show that the rubber teat 50 has a flared opening 84 to a bore which has a neck 48. The neck 48 has a narrower internal diameter than the internal diameter of the remainder of the bore, and a greater exterior diameter. The internal diameter of the neck 48 is less than the outer diameter of the needle 14, and the internal diameter of the remainder of the bore is greater than the outer diameter of the needle 14. The neck 48 is thus an interference fit on the needle 14, and by virtue of the interference fit, forms a seal between the remainder of the bore and the neck 48. The seal prevents blood from escaping from the teat 50 when the needle
14 is inserted into a patient. A blood collection vacuum vial 24 is inserted into the holder 12 to collect blood in a known manner.
In order to improve the seal of the neck 48 on the needle 14 further, and to secure the teat 50 in position on the needle 14 relative to the holder 12, the neck 48 is held in a compressed, improved interference fit in a cylindrical projection 40 extending inwardly from the rear of the bulkhead 20 of the holder 12 to define a neck containment formation. The wall of the cylindrical projection 40 has an axial slot or groove 42 to permit assembly of the needle 14 into the holder 12 prior to introduction of the neck 48 into the cylindrical projection 40.
Along one exterior edge of the axial slot 42 is provided a securing protuberance in the form of a radially extending flap or rail 86. As illustrated in Figure 9B, when the rail 86 is overwelded into the axial slot 42 it defines an effective needle securing formation 88 which prevents the needle being forced backwardly through the slot 42 in use.
Referring to Figures 11A to 13B of the drawings, a second embodiment of the invention includes an adapter 90, which is designed to be used with a conventional vacuum vial holder 92. Where the function of the component parts of the adapter 90 are essentially the same as those earlier described in relation to the safety phlebotomy device 10, similar descriptive numerals are used, distinguished by the suffix A.
The adapter 90 includes a body 94, with a needle (not shown), a needle shield 16A, and a rubber needle teat 50A. Two clasps 96 are provided on the adapter 90 to clasp the holder 12 to the adapter 90. The clasps 96 are resiliently biased to clasp the holder 92 in a compression and click fit.
A holder engaging clip formation 98 defined on the adapter 90 is provided to act in releasable clip-locking engagement with the lip 100 of. a rear finger tab formation 102 on the holder 92. As can be appreciated from Figures 13A and B, the combination of the resiliently biased clasps 96 and the releasable clip formation 98 ensures that the adapter 90 will be held in secure attachment to the holder 92, while a phlebotomy procedure is in progress, but will permit easy disengagement of the adapter 90 to allow the holder 92 to be used again, if so desired.
A needle teat 50A, in common with teat 50 earlier described, is provided with a neck 48A having a narrower internal diameter than the internal diameter of the remainder of the bore of the teat 50A, and a greater exterior diameter. The internal diameter of the neck 48A is less than the outer diameter of the needle (not shown), and the internal diameter of the remainder of the bore is greater than the outer diameter of the needle. The neck 48A is thus an interference fit on the needle, and by virtue of the interference fit, forms a seal between the remainder of the bore and the neck
48A. The seal prevents blood from escaping from the teat 50A when the needle is inserted into a patient.
The neck 48A of the teat 50A extends into a radially projecting flange 104 defined at the rear of the teat which is urged in a compression fit into a complemental recess 106 in the rear face of the front bulkhead 20A of the body 94. In addition to securing the teat 50A to the body 94, this arrangement also improves the interference fit, and therefore the seal, between the neck 48A and the needle.
In assembly, the holder 92 is introduced into the adapter 90 in the direction of arrow A in Figure 11A. The external diameter of the neck 48A of the teat is designed to provide a comfort compression fit with the bore of the concentric spigot 108 defined on the front wall 110 of the holder 92, thereby further improving the seal between the neck and the needle. With the holder 92 in its locked position within the adapter 90 as shown in Figures 13A and 13B, the front end of the spigot 108 abuts the rear of the flange 104, which acts as a rearwardly biasing compression washer, thereby improving the integrity of the locking means provided by the holder engaging clip formations 98 in co-operation with the holder lip 100, while at the same time securely locking the teat between the front wall 110 of the holder and the rear face of the bulkhead 20A of the body.
Save where specifically indicated to the contrary, functionally the adapter 90 in cooperation with the holder 92, operates in the same way as the safety phlebotomy device 10 earlier described with reference to Figures 1 to 10, and also shown in Figures 16A, 16B, 16C and 17 of the drawings.
Referring to Figures 14 and 15 of the drawings, in a third embodiment of the invention, a safety phlebotomy assembly 112 includes an adapter 114 which is designed to be used with a non-conventional (proprietary) vacuum vial holder 116. Where the function of the component parts of the safety phlebotomy assembly 112 are essentially the same as those earlier described in relation to the safety phlebotomy device 10 and the adapter 90, similar descriptive numerals are used, distinguished by the suffix B.
The adapter 114 has a body 118 with a needle (not shown), a needle shield 16B, and a rubber needle teat 50B.
Two clasps 96B are provided on the body 118 to enable the body to be mounted to the holder 116. The clasps 96B are resiliently biased to embrace the holder 116 in a compression and click fit.
A T-shaped locking stud 120 extending from the lower exterior surface of the holder 116 comprises an adapter engaging clip formation 122
designed to act in releasable clip-locking engagement with a T-shaped locking aperture 124 defined at the rear end of the guide channel 74B in the adapter 114. As can be seen from Figure 15, the combination of the resiliently biased clasps 96B and the releasable clip formation 122 ensures that the adapter 114 is held in secure co-operation with the holder 116 while a phlebotomy procedure is in progress, but permits easy disengagement of the adapter 114 to allow the holder 116 to be used again, if so desired.
The needle teat 50B and the cylindrical projection 40B extending rearwardly from the bulkhead 20B of the body 118 in function, appearance and inter-engagement, are essentially the same as teat 50 and cylindrical projection 40 described in Figures 7 to 9.
In assembly, the holder 116 is introduced into the adapter 114 in the direction of arrow B in Figure 14. The external diameter of the cylindrical projection 40B is designed to provide a comfort fit with the bore of the aperture 126 (shown in broken lines) defined on the front wall 128 of the holder 116, thereby further improving the seal between the neck and the needle. With the holder 116 in its locked position within the adapter 114 as shown in Figure 15, the front wall 128 of the holder 116 abuts the rear of the bulkhead 20B of the body 118, providing rearward biasing compression and improving the integrity of the locking means provided by the adapter engaging clip formation 122.
Referring to Figures 16A to 16C and 17 of the drawings, a method for assembling the safety phlebotomy device of Figures 1 and 2 is illustrated. In Figure 16A, the rear of the slide 62 of the needle shield 16 is introduced in the direction of arrow C into the slideway 18 of the holder 12. As the slide 62 continues to be inserted into the slideway 18, it will be seen from Figure 16B that this has the effect of angling the rear 130 of the needle shield 16 to clear of the retaining nibs 78 and locking barbs 82 on the holder, thereby avoiding damage to them.
Figures 16C and 17 illustrate how the T-shaped assembly locking tab 56 is urged in the direction of arrow D in clip-locking engagement into a complemental T-shaped assembly locking aperture 124 defined in the holder 12. At this point the needle shield 16 is non-releasably engaged with the holder 12, and free to slide displaceably along the holder.
In the final steps of the assembly (not illustrated) the front point 34 of the needle 14 is introduced through the rear of the holder 12 into the groove 64.3 of the needle shield 16 and pushed forward until the cranked or radially extending portion 30 of the needle engages clips 38 in click-fit engagement; rail 86 is over-welded into axial slot 42 to constitute needle check formation 88, neck 48 of the teat 50 is then passed over the rear point 36 of the needle 14 and urged into a compression fit within cylindrical projection 40, and finally the needle shield 16 is displaced forwardly along the
holder 12 into the storage position shown in Figure 2, prior to packaging and sterilisation.
Referring to Figures 21 and 22 of the drawings, a phlebotomy device 140 in accordance with a fourth embodiment of the invention, is shown. Where the functions of the component parts of the phlebotomy device 140 are essentially the same as those earlier described in relation to the phlebotomy device 10, similar descriptive numerals are used, distinguished by the suffix C.
The phlebotomy device 140 includes a vacuum vial holder 12C, a needle 14C and a needle shield 142. The holder 12C has a front bulkhead 20C and a forwardly extending tongue 26C, ending with a tip 144.
Two locking formations or detents 146 extend laterally from sides of the needle shield 142, which are resiliently flexible and are outwardly biased against internal vertical walls of the guide channel 74C defined on the barrel 12C and tongue 26C, thereby creating a friction lock between the needle shield 142 and the guide channel 74C. This friction lock ensures that when the needle shield 142 is set in a desired position, it will remain in that position until sufficient force is applied to the needle shield 142 to overcome the friction lock. The detents 146 are outwardly biased by being curved in a horizontal plane.
In the disposal position, the detents 146 are pushed beyond the tip 144 of the tongue 26C. This enables the detents 146 to move resiliently outwardly and to abut against the tip 144 of the tongue 26C. The needle shield 142 cannot be retracted from this position without depressing or breaking of the detents 146. The needle shield 142 is thus for practical purposes non-releasably locked in the disposal position. As in the storage i position, the point 34C of the needle 14C is shielded by the needle shield 142 when the needle shield is in its disposal position.
Referring to Figures 23 to 26 of the drawings, a phlebotomy device 150 in accordance with a fifth embodiment of the invention, is shown. Where the functions of the component parts of the phlebotomy device 150 are essentially the same as those earlier described in relation to the safety phlebotomy device 10, similar descriptive numerals are used, distinguished by the suffix D.
The phlebotomy device 150 includes a vacuum vial holder 12D, a needle 14D and a needle shield 16D.
The needle shield 16D is injection moulded from a rigid, low cost thermoplastic such as polypropylene, styrene, ABS (Acrylonitrile- butadiene-styrene), or the like. The needle shield 16D has two barbed detents 154 for non-releasably locking the needle shield 16D in engagement with complemental barbs 156, disposed on the inwardly projecting retaining
walls of the guide channel 74D and the tongue 26D. Two shield engaging formations defining retaining protuberances 158 are provided for releasably retaining the shield 16D in a storage or packed position.
The needle shield 16D can be slid between a storage position as shown in Figure 23 and an unshielded fully retracted operable position as shown in Figure 25. It can also be slid between a fully retracted position as shown in Figure 25 to a disposal position (not shown).
Referring to Figure 24, the needle shield 16D is shown in the storage position wherein the barbed detents 154 are disposed rearwardly of the complemental barbs 156. In order to retract the shield 16D into the fully retracted position of Figure 25, barbs 160 on the needle shield 16D are urged slideably over the retaining protuberances 158. To bring the shield 16D into the disposal position, barbs 160 are urged forwardly over barbs 156 on the slideway into recesses 162. At the same time, barbs 156 are brought into locking engagement with locking recesses 154.
The needle shield 16D cannot be retracted from the disposal position, without breaking off the barbs 156 and 160. The needle shield 16D is thus for practical purposes non-releasably locked in the disposal position and the phlebotomy device 150 can thus be disposed of without fear of someone being pricked by the point 34D of the needle 14D.
Referring to Figure 27 of the drawings, an alternative arrangement of the features shown in Figure 26 are shown. Where the functions of the component parts are essentially the same as those shown in Figure 26, similar descriptive numerals are used, distinguished by the suffix
E.
It will be appreciated that the locking and storage arrangement provided collectively by barbs and barbed detents 154,156,160 and 162, and by retaining protuberances 158, may be disposed at various locations along the needle shield 16D and guide channel 74D, respectively.
Common to all embodiments of the invention illustrated and/or described above, the assembled safety devices described can be operated entirely one-handedly during a blood collection or phlebotomy procedure, up to and including safe disposal of the assembled device, thereby leaving the practitioner's other hand completely free to handle site preparation and the like. It will further be appreciated that at no time during the phlebotomy procedure is the hand operating the assembled device brought in front of the needle point, and that the potentially dangerous practice of re-capping the needle after use is avoided entirely.
The invention described and/or illustrated holds the further advantages that the offset provided by the cranked needle of the present invention avoids the need to bend the needle during insertion, in order to
achieve acute tangentiality to the patient's skin surface. It also ensures that the bevel of the front point of the needle is consistently upwardly disposed relative to the patient's skin. It further offers the practitioner the facility of taping the device in situ so as to free both hands while minimising the trauma involved in inadvertently jogging the needle while it is lodged in the vein, particularly during successive insertions of vacuum vials in order to collect a number of blood samples during the one procedure.