Patent Publication Number: US-2023148921-A1

Title: Blood Collection Device

Description:
1. FIELD OF THE INVENTION 
     This invention is a blood collection device for medical use having safety features that include a rearwardly biased venipuncture needle that is selectively retractable into a needle retraction chamber to reduce the likelihood of accidental needle sticks following use. A distinguishing feature of one embodiment of the invention is a tubular needle cap open at both ends that is releasably engageable with the inner wall of a hub portion of the flexible wing. Another distinguishing feature of one or more embodiments of the invention is an injection molded boss projecting outwardly from the nose of the slide member that is cooperatively configured and engageable with a window disposed in the hub of the flexible wing to seat the wing to the nose of the slide member during assembly of the device prior to packaging and use. Another distinguishing feature of one or more embodiments of the invention is an improvement to the cooperatively configured structures of the slide assembly and the body that facilitate sliding lateral movement of the body relative to the slide assembly during repositioning prior to needle retraction but prevent the slide member and the body from becoming disengaged accidentally prior to or following use 
     2. DESCRIPTION OF RELATED ART 
     Blood collection sets have previously been made with a closed-end needle cap that releasable engages a ridge, rim or seating surface on the nose of the barrel, and desirably remains in place until use of the device. Some devices have been made with needle caps that also comprise a projecting locking member insertable into a recess or needle retraction cavity to limit relative sliding movement between a frontal attachment and a body, and thereby prevent premature needle retraction that can render a device inoperable for the intended purpose prior to use. A prior art device with an integral tube seal disposed between the body and a laterally moveable slide member is disclosed, for example, in U.S. patent Ser. No. 10/646,148. 
     Notwithstanding the benefits and advantages achievable through the use of previously disclosed devices, a blood collection set is needed that desirably embodies: a flexible wing assembly providing a stable platform for drawing blood without allowing excessive needle movement causing discomfort to a patient (particularly children) during a blood draw; a needle cap preferably held in place by engagement with an inwardly facing, preferably elastomeric, surface of a hub portion of the flexible wing; and a slide member supporting the needle, needle cap, flexible wing and a rearwardly biased needle in lateral sliding engagement with a body comprising a rearwardly extending fluid path and a parallel needle retraction chamber into which the needle is retracted following use by sliding the body laterally relative to the slide member to release the rearwardly biased needle. 
     SUMMARY OF THE INVENTION 
     A blood collection device is disclosed that desirably embodies: a flexible wing assembly providing a stable platform for drawing blood without allowing excessive needle movement causing discomfort to a patient (particularly children) during a blood draw; a needle cap preferably held in place by engagement with an inwardly facing, preferably elastomeric, surface of a hub portion of the flexible wing; and a slide assembly supporting the needle, needle cap, flexible wing and a rearwardly biased needle in lateral sliding engagement with a body comprising a rearwardly extending fluid flow path and a parallel, spaced-apart needle retraction chamber into which the needle is retracted following use by sliding the body laterally relative to the slide member to release the rearwardly biased needle. 
     This invention is a blood collection device for medical use having a rearwardly biased venipuncture needle that is selectively retractable into a needle retraction chamber to reduce the likelihood of accidental needle sticks following use. A distinguishing feature of the invention is a tubular needle cap open at both ends that is releasably engageable with the inner wall of a hub portion of the flexible wing. Another distinguishing feature of the invention is an injection molded boss projecting outwardly from the nose of the slide member that is cooperatively configured and engageable with a window disposed in the hub of the flexible wing to position and attach the wing to the nose of the slide member during assembly of the device prior to packaging and use. Another distinguishing feature of the invention is an improvement to the cooperatively configured ramps and stop surfaces of the slide member and the body that facilitate sliding lateral movement of the body relative to slide member during repositioning prior to needle retraction following a blood draw but prevent the slide member and the body from becoming disengaged prematurely and from reversing the direction of travel during repositioning. 
     Although the subject device is primarily envisioned for use in performing vascular blood draws, it will be apparent to those skilled in the art upon reading the disclosure in relation to the accompanying drawings that the subject device is also adaptable for use in drawing other bodily fluids. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The syringe of the invention is further described and explained in relation to the following drawings wherein: 
         FIG.  1    is an exploded view of a satisfactory embodiment of the blood collection set of the invention; 
         FIG.  2    is a top front perspective view of the assembled device of  FIG.  1   ; 
         FIG.  3    is a top front perspective view as in  FIG.  2    but with the needle cap removed; 
         FIG.  4    is top plan view of the device as in  FIG.  2    with a segment of the blood collection tubing cut away for illustrative purposes; 
         FIG.  5    is left side elevation view of the device as in  FIG.  4   ; 
         FIG.  6    is a rear elevation view of the device of  FIG.  4   ; 
         FIG.  7    is a front elevation view of the device of  FIG.  4   ; 
         FIG.  8    is a cross-sectional view taken along line  8 - 8  of  FIG.  7   ; 
         FIG.  9    is a cross-sectional elevation view as in  FIG.  8    but with the needle cap removed; 
         FIG.  10    is a cross-sectional view taken along line  10 - 10  of  FIG.  4   ; 
         FIG.  11    is a view as in  FIG.  4    with the needle cap removed and with the body repositioned laterally relative to the slide member and the needle retracted; 
         FIG.  12    is a view as in  FIG.  5    but with the body repositioned laterally relative to the slide member and the needle retracted; 
         FIG.  13    is a view as in  FIG.  7    but with the needle cap removed and the needle retracted; 
         FIG.  14    is a view as in  FIG.  9    but with the body repositioned laterally relative to the slide member and the needle retracted; 
         FIG.  15    is a cross-section view as in  FIG.  10    but with the body repositioned relative to the slide member and the needle retracted; and 
         FIG.  16    is an enlarged bottom perspective view, partially in section and partially cutaway, of the front portion of the device with the needle cap in place and prior to repositioning the body relative to the slide member to initiate needle retraction. 
     
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring to  FIGS.  1 - 7   , blood collection device  10  comprises body  12 , slide assembly  14 , device stabilization member  16 , fluid flow tubing  28  with end connector fitting  18 , and tubular needle cap  36 . Body  12  satisfactorily comprises a longitudinally extending fluid flow channel  22  having proximal and distal ends and a parallel, laterally spaced-apart needle retraction chamber  24  having a closed proximal end and a distal open end. An annular fluid seal  20  with a longitudinal flow path coaxially aligned with fluid flow channel  22  is desirably made of a compressible elastomeric material, is satisfactorily seated inside a recess disposed in the distal open end of fluid flow channel  22  (visible in  FIGS.  8 - 9   ). Body  12  further comprises upwardly and downwardly projecting structures  42  that are cooperatively configured with and slidably engage structures  40  of slide assembly  14  (visible in  FIGS.  10 - 15   ). Textured touch surface  26  is desirably provided to facilitate selective lateral repositioning of body  12  relative to slide assembly  14  in a plane transverse to fluid flow channel  22  during use of blood collection device  10  as described in greater detail below. Body  12  of blood collection device  10  is preferably injection molded from a medical grade polymeric material that is transparent or sufficiently translucent to permit blood flowing through the body to be viewed by a user. 
     Slide assembly  14  desirably comprises an integrally molded plastic body further comprising projecting structures  40  configured to slidably engage structures  42  of body  12  to facilitate sliding lateral engagement between slide assembly  14  and body  12  as further described below. Slide assembly  14  further comprises a forwardly projecting nose  38 , slotted collar  46  and touch surface  44 . Touch surface  44  is preferably textured in the same manner as oppositely facing touch surface  26  of body  12  and facilitates selective repositioning of body  12  relative to slide assembly  14  during needle retraction following a blood draw, which is further discussed below. Referring particularly to  FIG.  1   , slide assembly  14  further comprises a compressed coil spring  32  that is seated inside the forwardly projecting nose  38  and has an inside diameter sufficient to allow the insertion of the distal shaft portion of needle holder  30  prior to attachment of slide assembly  14  to body  12  during assembly of blood collection device  10 . Although forwardly projecting needle (or cannula)  34  is shown behind nose  38  in the “exploded” view of  FIG.  1   , the assembly of device  10  is preferably effectuated by inserting the blunt, proximal end of needle  34  into nose  38  and needle holder  30  after slide assembly  14  is attached to body  12  to hold spring  32  in compression during installation of needle  34 . Attachment of needle  34  to needle holder  30  facilitates the formation of a continuous, coaxially aligned fluid flow path from needle  34  and needle holder  30 , through annular fluid seal  20  and through fluid flow channel  22  into fluid flow tubing  28 . 
     Device stabilization member  16  of blood collection device  10  is believed to be structurally different from and performs functions not common to “wings” of the type previously disclosed and used in other commercially available or prior art medical devices. Referring particularly to  FIGS.  1  and  16   , and more generally to  FIGS.  2 - 7   , device stabilization member  16  is desirably fabricated from a flexible polymeric material and preferably from an elastomeric material suitable for medical use for the intended purpose. Device stabilization member  16  is desirably integrally formed, although it can also be made as a composite construction including a molded plastic portion and an elastomeric or rubbery portion that are molded, coextruded, laminated, glued, welded or otherwise connected to form the desired overall structure. Principal elements of device stabilization member  16  include cylindrical hub  48  having an inside wall  50 , and two oppositely projecting flexible wings  52 ,  54  that are adapted to rest on or be taped to a bodily surface following vascular insertion of needle  34  that projects forwardly through nose  38 . When so used and secured, flexible wings  52 ,  54  help prevent the tip end of needle  34  from moving inside a vein or otherwise beneath the skin of a patient with whom blood collection device  10  is used. The downwardly facing surface of wings  52 ,  54  are desirably approximately level with the downwardly facing portion of cylindrical hub  48  and can be textured as shown in  FIG.  16    if desired to help reduce the likelihood of slippage between the surfaces and underlying skin when blood collection device  10  is in use. 
     According to one preferred embodiment of slide assembly  14  and device stabilization member  16 , an integrally molded boss  66  (visible in  FIG.  16   ) projects outwardly from nose  38  through slotted collar  46 , and is received through a pre-formed window  68  (also visible in  FIG.  16   ) in cylindrical hub  48  to attach cylindrical hub  48  to slide assembly  14  and further stabilize slide assembly  14  and body  12  relative to forwardly projecting needle  34  and to the patient with whom device  10  is being used. Boss  66  prevents cylindrical hub  48  from rotating relative to slide member  14  and body  12 , thereby cooperating with flexible wings projecting laterally from cylindrical hub  48 . 
     Referring again to  FIG.  1    end connector fitting  18  is disclosed as an example of one of the many commercially available fittings of the type that can be used with medical products to attach flexible fluid flow tubing  28  to a polymeric bag or other receptacle intended to receive the blood or other bodily fluid being drawn from a patient through device  10 . The distal end of fluid flow tubing  28  can be inserted into frictional engagement with or otherwise attached to fluid flow channel  22  of body  12 , and the proximal end of fluid flow tubing  28  can be inserted into frictional engagement with, or be otherwise connected to, distally facing cylindrical opening  58  of end connector fitting  18  that is in fluid communication with proximally facing luer connector  56  to complete a continuous fluid flow path through blood collection device  10 . Two opposed, laterally extending wings  60 ,  62 , are desirably provided to assist in maintaining a desired rotational alignment of end connector fitting  18  relative to body  12  and to device stabilization member  16 . The continuous, substantially linear, fluid flow path passes through needle  34 , needle holder  30  of slide assembly  14 , annular fluid seal  20 , fluid flow channel  22  of body  12 , flexible fluid flow tubing  28  and end connector fitting  18  desirably remains open from the time of vascular insertion of needle  34  until body  12  is repositioned laterally relative to slide assembly  14  to initiate needle retraction as described in greater detail below. 
     Referring to  FIGS.  1 - 3 ,  8  and  9   , tubular needle cap  36  is desirably cylindrical, having a substantially constant diameter, and unlike many conventional needle caps for medical devices, is open at both the proximal and distal ends. The principal purposes of tubular needle cap  36  are to protect against accidental needle sticks and to protect the tip end of forwardly projecting needle  34  from being bent or blunted prior to use of the device. Because blood collective devices  10  are desirably individually packaged during manufacture, it is not necessary that the distal end be closed to prevent atmospheric contamination prior to use. The length of tubular needle cap  36  is satisfactorily such that the distal end extends sufficiently past the distal tip end of needle  34  that the needle tip is not reachable to produce an accidental needle stick by medical personnel unpackaging and handling blood collection device  10  prior to use. The polymeric material and wall thickness of tubular needle cap  36  are desirably selected and determined so that the needle cap is inflexible enough that it will not be accidentally flexed or bent into contact with needle  34  during normal handling and storage before it is removed just prior to use of device  10 . 
     Unlike conventional needle caps used with similar medical devices, tubular needle cap  36  is not molded with one or more structural elements disposed at or near the proximal end that are specially designed and molded to frictionally engage and hold some part of the nose or body of a medical device. Instead, tubular needle cap  36  can be molded or extruded with a smooth, cylindrical inside and outside wall, provided that the inside and outside diameters permit the proximal end of tubular needle cap  36  to be installed over and around forwardly projecting nose  38  and inside the outwardly stretched, distal end of cylindrical hub  48  to be held in that position by a constrictive holding force exerted radially inward against the outer surface of tubular needle cap  36  by the elastomeric inside surface of cylindrical hub  48  of device stabilization member  16 . During assembly of blood collection device  10 , cylindrical hub  48  is desirably stretched or expanded outwardly for two purposes—first, to allow window  68  through cylindrical hub  48  ( FIG.  16   ) to receive and be installed over and around projecting boss  66  of forwardly projecting nose  38  of slide assembly  14 ; and second, to allow the proximal end of tubular needle cap  36  to be inserted between nose  38  and inside the distal end of cylindrical hub  48 . After cylindrical hub  48  and the proximal end of tubular needle cap  36  are properly positioned relative to forwardly projecting nose  38 , cylindrical hub  48  is desirably allowed to relax and constrict to exert a holding force against the outside surface of the proximal end of tubular needle cap  36  that is sufficient to maintain the desired positional relationship between them until such time a tubular needle cap  36  is manually removed from the front of slide assembly  14  prior to use of blood collection device  10 . 
       FIG.  8    illustrates blood collection device  10  in a fully assembled pre-use position wherein slide assembly  14  is disposed in lateral sliding engagement with body  12 , the proximal end of needle  34  is installed inside needle holder  30 , compressed spring  32  seated inside forwardly projecting nose  38  is biasing needle holder  30  rearwardly into abutting contact with the forwardly facing distal surface of annular fluid seal  20 , the distal end of flexible fluid flow tubing  28  is installed inside fluid flow channel  22  of body  12 , and the proximal end of fluid flow tubing  28  is installed inside end connector fitting  18 . As best seen in  FIG.  8   , whenever tubular needle cap  36  is installed over needle  34  and is inserted into engagement between forwardly projecting tubular nose  38  and the forwardly extending portion of cylindrical hub  48  of device stabilization member  16 , the elastomeric holding force exerted against the outwardly facing surface of tubular needle cap  36  is desirably such that tubular needle cap  36  is held in place relative to slide assembly  14  and body  12  until such time as tubular needle cap  36  is intentionally removed prior to use of blood collection device  10 . When blood collection device  10  is configured as shown in  FIG.  8   , a continuous, substantially linear, coaxially aligned fluid flow path is established from needle  34  to and through end connector fitting  18  that is accessible by removing tubular needle cap  36  as shown in  FIG.  9   . Once tubular needle cap  36  is removed from the front of blood collection device  10  prior to vascular insertion of needle  34 , tubular needle cap  36 , which is not contaminated, can be disposed of in the trash without special safeguards. 
     FIGI.  10  is a cross-section taken along line  10 - 10  of  FIG.  4    and shows the lateral sliding engagement of body  12  with slide assembly  14  when body  12  is disposed in the pre-use position where tubular needle cap  36  is still attached and aligned with annular fluid seal  20  in a forwardly facing recess of fluid flow channel  22 . The leading, first set of inclined top and bottom ramps  42  of body  12  is desirably configured to slide past top and bottom ramps  40  of slide assembly  14  during assembly of blood collection device  10 , and the oppositely facing shoulders of ramps  40  desirably prevent body  12  from moving in a reverse direction relative to slide assembly  14  and accidentally disengaging prior to use of blood collection device  10 .  FIGS.  4 - 10  and  16    all disclose blood collection device  10  with a coaxially aligned fluid flow path between needle  34 , annular fluid seal  20 , fluid flow tube  28  and end connector fitting  18 . With blood collection device  10  disposed in this position, and following the selective removal of tubular needle cap  36 , needle  34  can be inserted into a patient and if desired, wings  52 ,  54  can be taped to hold device  10  steady as blood is collected through fluid flow tube  28 . Because body  12  and flu id flow tub  28  are preferably either transparent or translucent, a user can observe blood flowing through body  12  to confirm proper vascular insertion of needle  34  in the patient. 
     Following the blood draw, body  12  is desirably repositioned transversely relative to the fluid flow direction and laterally relative to slide assembly  14  as shown in  FIGS.  11 - 15    by exerting manual pressure against touch surfaces  26 ,  44  of slide assembly  14 , thereby causing the second set of top and bottom ramps  42  of body  12  to slide laterally past top and bottom ramp  40  of slide assembly  14 , after which they are prevented by the facing and contacting shoulders from reversing direction subsequent to the repositioning. As touch surfaces  26 ,  44  are squeezed toward each other by the user, the proximal end of needle holder  30  is moved laterally out of abutting contact with the distal end of annular fluid seal  20  and fluid seal  20  expands into facing contact with the rearwardly facing surface of slide assembly  14 . This contact helps prevent collected bodily fluid from leaking forwardly out of fluid flow path  22 . At the same time, the larger diameter opening into needle retraction chamber  24  becomes aligned with the smaller diameter head of needle holder  30 , allowing compressed spring  32  to drive needle holder  30  and needle  34  rearwardly into needle retraction chamber  24 . Tubular nose  38  of slide assembly  14 , needle  34 , needle holder  30  and relaxed compression spring  32  and needle retraction chamber  24  are desirably sized and cooperatively configured so that the distal tip end of needle  34  does not extend forwardly of tubular nose  28  after needle holder  30  is driven rearwardly into needle retraction chamber  24 . Blood collection device  10  is thereby prevented from causing accidental needle sticks by protecting the distal end of needle  34  inside forwardly projecting nose  38  following needle retraction, and further use of the device is also prevented due to bridging of the lateral sliding surfaces by expanded spring  32  and by the irreversibly engaged shoulder surfaces of ramps  40 ,  42  between the facing portions of slidably engaged slide assembly  14  and body  12 . 
     It will become apparent to those of ordinary skill in the art upon reading this specification in relation to the accompanying drawings that various other modifications and alterations can also be made to the embodiments disclosed here, and it is intended that the scope of the invention be limited only by the broadest interpretation of the appended claims to which the inventors are legally entitled.