Abstract:
A medical device configured as a blood collection tube holder, the device having a body with two spaced-apart, oppositely facing, coaxially aligned needles including a forwardly facing venipuncture needle and a rearwardly facing fluid discharge needle, the two needles being held by first and second needle holders separated by a compressible fluid seal defining part of a fluid path between the two needles and the two needle holders. The body also includes a discharge needle displacement member that is manually repositioned following removal of the last blood tube holder so that the discharge needle displacement member contacts the second needle holder and displaces the second needle holder and the fluid discharge needle laterally inside the body to initiate retraction of the venipuncture needle into a rearwardly projecting needle retraction chamber.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 15/202,118, filed Jul. 5, 2016. 
     
    
     TECHNICAL FIELD 
       [0002]    This invention is a medical device, and more particularly, a blood collection tube holder configured for use in drawing and collecting samples of bodily fluids, and especially vascular fluids such as blood. The invention includes a body having two longitudinally separated, oppositely facing, coaxially aligned needles. A venipuncture needle faces forwardly and can be inserted into a patient to withdraw fluid. A discharge needle faces rearwardly and is insertable into the forwardly facing end of a blood collection tube used in conjunction with the subject device. The venipuncture needle is retractable following use and both needles remain inside the body of the device for safe disposal. Use of the device reduces the likelihood of inadvertent needle-stick injuries and contamination of health care workers and others with blood-borne pathogens. 
       BACKGROUND 
       [0003]    U.S. Pat. No. 5,810,775 and RE39,107 disclose Medical devices such as blood collection tube holders having a single double-ended needle that is retractable into the cylindrical body of the tube holder following use. Needle retraction is initiated by closing a hinged cap upon removal of a fluid collection tube, which causes a coaxially aligned inner sleeve to move forwardly and release a rearwardly biased needle. 
         [0004]    U.S. D645,962 and U.S. D660,420 disclose a housing for a collection device for bodily fluids that comprises a substantially cylindrical section having a forwardly extending cylindrical nose, an open rear end, a plurality of longitudinally extending ribs disposed on each side of the cylindrical section, and an elongate arm pivotably mounted near the rear of the housing over an upwardly facing slot in the tube holder. 
         [0005]    U.S. Pat. No. 8,469,927 discloses a fluid flow control device having an actuator that moves translationally relative to the housing but does not have a rearwardly facing needle and is not disclosed for use with a fluid collection tube insertable into the housing. 
         [0006]    U.S. Pat. No. 8,496,600 discloses a non-reusable collection device for bodily fluids such as vascular blood, the device having a housing configured similarly to that of U.S. D645,962, wherein a single, rearwardly biased double-ended needle is constrained prior to needle retraction by a rotatably mounted lug ring. The needle is released during retraction by depressing a pivotably mounted trigger connected to the body of the device to contact and rotate the lug ring, after which the needle holder is driven into a retraction cavity disposed inside the trigger while the trigger is disposed at an angle that intersects the central longitudinal axis through the housing 
         [0007]    U.S. Pat. No. 9,247,899 discloses a blood draw device with a single, double-ended retractable needle that is similar in form and function to the device of U.S. Pat. No. 8,496,600 except that a retainer clip retains the rearwardly biased double-ended needle until the front portion of an actuator (similar to the trigger of the &#39;600 patent) is pivoted downwardly to cause the retainer clip to release the needle holder, after which a compressed spring expands and drives the needle holder into a retraction cavity inside the actuator that is disposed at an angle that intersects the central longitudinal axis through the housing. 
       SUMMARY OF THE INVENTION 
       [0008]    A medical device is disclosed that is desirably configured as a blood collection tube holder. The subject device satisfactorily comprises a molded plastic body having a generally cylindrical interior space that is configured to receive and engage a stoppered end of a conventional blood collection tube such as those typically used in conjunction with such devices. The device of the invention desirably includes two spaced-apart, oppositely facing, coaxially aligned needles held inside the body. One needle is a forwardly projecting venipuncture needle having a beveled tip suitable for insertion into a vein of a patient. The venipuncture needle is held by a first needle holder that is rearwardly biased, preferably by a compressed spring. The second needle is a rearwardly facing fluid discharge needle that is held by a second needle holder supported inside the body and that is insertable through the stoppered end of a blood collection tube. A cylindrical fluid seal is desirably disposed between the first and second needle holders. The fluid seal has a longitudinally extending passageway that is coaxial with the two needles and defines part of a fluid path between the two needles and the two needle holders. The fluid seal is desirably made of a compressible polymeric material that will resist fluid leakage around the seal when it is compressed slightly during installation between the two needle holders. 
         [0009]    The blood collection tube holder also desirably comprises a discharge needle displacement member that slidably engages the body and is used to initiate retraction of the venipuncture needle following collection of a bodily fluid such as blood. As the stoppered end of the blood collection tube separates from the fluid discharge needle following collection of a blood sample, a collapsible protective polymeric sheath disposed around the fluid discharge needle expands to cover the rearwardly facing tip of the fluid discharge needle. The discharge needle displacement member desirably includes a front portion configured to provide sliding engagement with guide members disposed behind the front wall of the body, and also has a rearwardly projecting needle retraction chamber having a forwardly facing open end that is accessed through an opening in the front portion. The front portion of the discharge needle displacement member desirably further includes an outwardly facing, textured touch surface to which pressure is applied manually to initiate transverse sliding movement of the discharge needle displacement member relative to the body after a blood collection tube is withdrawn from the blood collection tube holder. 
         [0010]    As the discharge needle displacement member slides further into the body of the device in response to the manually applied pressure, it moves in a direction that is transverse to the fluid flow path through the blood collection tube holder. When the front portion of the discharge needle displacement member contacts the second needle holder, it the second needle holder to disengage from the fluid seal, and displaces the second needle holder and fluid discharge needle to a resting position that is laterally spaced apart from the needle retraction chamber but is still protected inside the body. As the second needle holder and the fluid discharge needle attached to it are moved away from the fluid seal, the forwardly facing opening into the needle retraction chamber is moved into coaxial alignment with the fluid seal, the first needle holder and the venipuncture needle. Once the first needle holder and the needle retraction chamber are coaxially aligned, the fluid seal, the rearwardly biased, first needle holder and the venipuncture needle are propelled rearwardly into the needle retraction cavity. In a preferred embodiment of the invention, the rearwardly directed biasing force is sufficient to withdraw the tip of the venipuncture needle directly from the patient&#39;s body and inside the body of the blood collection tube holder, thereby significantly reducing the likelihood of an inadvertent needle stick injury or pathogenic contamination to others. 
         [0011]    This section of the application also incorporates by reference into this Summary of the Invention the statements previously made in the section of this patent application subtitled “Technical Field.” These and other features, objects and advantages of the present invention will become better understood from a consideration of the following detailed description of the preferred embodiments and appended claims in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The system and method of the invention are further described and explained in relation to the following drawings wherein: 
           [0013]      FIG. 1  is a top front perspective view of one embodiment of a medical device of the invention with a locking cap installed on the device; 
           [0014]      FIG. 2  is a top front perspective view as in  FIG. 1  but with the locking cap removed; 
           [0015]      FIG. 3  is an exploded top front perspective view of the medical device of  FIG. 1 ; 
           [0016]      FIG. 4  is an exploded top rear perspective view of the medical device of  FIG. 1 ; 
           [0017]      FIG. 5  is a front elevation view of the medical device of  FIG. 1 ; 
           [0018]      FIG. 6  is a cross-sectional view taken along line  6 - 6  of  FIG. 5 ; 
           [0019]      FIG. 7  is a rear elevation view of the medical device of  FIG. 1 ; 
           [0020]      FIG. 8  is a detail view taken from  FIG. 7 ; 
           [0021]      FIG. 9  is a front perspective view as in  FIG. 2 , with a cross-section taken behind the front wall of the body and through the front part of a discharge needle displacement member; 
           [0022]      FIG. 10  is a front elevation view of the device as depicted in  FIG. 9 ; 
           [0023]      FIG. 11  is a side elevation view of the device of  FIG. 2 ; 
           [0024]      FIG. 12  is a top plan view of the device of  FIG. 2 ; 
           [0025]      FIG. 13  is a front perspective view as in  FIG. 9 , but with the discharge needle displacement member moved into contact with the discharge needle holder prior to retraction of the venipuncture needle; 
           [0026]      FIG. 14  is a front elevation view of the device as depicted in  FIG. 13 ; 
           [0027]      FIG. 15  is a front perspective view of the device of  FIG. 2  after the venipuncture needle is fully retracted; 
           [0028]      FIG. 16  is a front elevation view of the device as depicted in  FIG. 15 ; 
           [0029]      FIG. 17  is a rear elevation view of the device as depicted in  FIG. 15 ; 
           [0030]      FIG. 18  is a side elevation view of the device as depicted in  FIG. 15 ; 
           [0031]      FIG. 19  is a cross-sectional view taken along line  19 - 19  of  FIG. 17 ; and 
           [0032]      FIG. 20  is a cross-sectional view taken along line  20 - 20  of  FIG. 17 . 
       
    
    
       [0033]    In each drawing figure, the subject device is depicted in an orientation wherein the height of the flange around the rear opening of the device is greater than the width of the flange and the textured touch surface of the discharge needle displacement member faces upwardly relative to the body. Accordingly, the bevel surface of the venipuncture needle is also depicted facing upwardly to facilitate insertion of the needle into a vein of a patient. It should be appreciated by those of skill in the art upon reading this disclosure, however, that some medical personnel may prefer to use the device in an orientation that is rotated 90 degrees around its longitudinal axis, so that the flange is wider that it is high and so that the touch surface of the discharge needle displacement member faces to the side rather than upwardly as shown in the accompanying drawings. Where the subject device is recommended to be used in the second orientation, with the touch surface of the discharge needle displacement member facing to the side, the venipuncture needle will still desirably be installed in the device with the needle bevel facing upwardly (not facing the skin of the patient at the insertion point) as depicted in the accompanying drawings. 
       DETAILED DESCRIPTION 
       [0034]    Referring to  FIG. 1 , blood collection tube holder  100  satisfactorily comprises body  102 , discharge needle displacement member  104  and removable needle cap  106 . Body  102  further comprises front wall sections  136 ,  158 , outwardly projecting rear flange  134 , and optional textured gripping surfaces  103 ,  101  (with  101  being visible in  FIG. 4 ). Discharge needle displacement member  104  desirably comprises outwardly facing textured touch surface  130  and rearwardly projecting needle retraction chamber  105 . Referring to  FIG. 2 , removable needle cap  106  of  FIG. 1  is removed to reveal forward projecting venipuncture needle  108  held by needle holder  110  seated inside nose  138  of body  102  in addition to parts already mentioned in relation to  FIG. 1 . 
         [0035]    Referring to  FIG. 3 , removable needle cap  106  further comprises opposed textured gripping surfaces  148 , tapered cylindrical body  156  having closed front end  152  and rear flange  150 , and rearwardly projecting, selectively releasable locking arm  154 . Body  102  further comprises substantially cylindrical outside wall  132 , an elongate opening  124  disposed between longitudinally extending wings  125 ,  127 , guide structures  144 ,  145  disposed behind front wall  136 , and front opening  140  into interior passage  141  inside nose  138 . Notch or recess  142  is provided in front wall  136  of body  102  to provide clearance for releasable locking arm  154  of removable needle cap  106 . Recess or orifice  131  is optionally provided in the forwardly facing surface of flange  134  between wings  125 ,  127  for use in releasably engaging and supporting rearwardly facing end  107  of needle retraction chamber  105  as further discussed below in relation to  FIG. 4 . 
         [0036]    Still referring to  FIG. 3 , the front portion of discharge needle displacement member  104  further comprises front opening  128  that facilitates access into needle retraction chamber  105 , and opposed arms  124 ,  126  that are slidably engageable with cooperatively sized and configured guide structures  144 ,  145  disposed behind front wall  136  of body  102 . Latches  115 ,  117  on opposed arms  124 ,  126  are configured to slide past opposed shoulders inside the front portion of body  102  during installation of discharge needle displacement member  104  inside body  102  during assembly of blood collection tube holder  100  as indicated by arrows  121 ,  122 . 
         [0037]    Also disposed inside body  102  of blood collection tube holder  100  are compression spring  120  (depicted in expanded condition prior to compression), venipuncture needle  108  having a forwardly projecting beveled end  160  and an opposed blunt end that is insertable into axial bore  162 , where it can be held in place by a UV-curable adhesive or by any other similarly effective conventional means. During assembly of blood collection tube holder  100 , spring  120  is desirably seated inside nose  138  and is disposed around venipuncture needle  108  and the shaft portion of needle holder  110 , and is constrained behind larger diameter head portion  164  of needle holder  110 . 
         [0038]    Body  102  of blood collection tube holder  100  also comprises needle holder  114  for rearwardly facing fluid discharge needle  116 . Needle holder  114  is desirably configured with a front portion  168  that slidably engages guide members  144  behind front wall  136  of body  102  and further comprises intermediate portion  169 , rearwardly projecting portion  172  and centrally disposed longitudinal bore  170  that is desirably coaxially aligned with needle holder  110 . Forwardly facing end  174  of fluid discharge needle  116  is desirably inserted into bore  170  and is held in place by a UV-curable adhesive or another similarly effective conventional means. Rearwardly facing tip  176  of needle  116  is desirably configured to penetrate the stoppered end of a conventional blood collection tube (not shown) when the blood collection tube is inserted through the opening defined by rear flange  134  of body  102  and into cylindrical cavity  133  inside body  102  (visible in  FIGS. 4 and 6 ) prior to use. Collapsible elastomeric sheath  118  is substantially cylindrical and comprises open end  178  communicating with an internal bore and close end  182 . Collar  180  is provided for use in frictionally attaching sheath  118  to rearwardly projecting portion  172  and holds collapsible sheath  118  in position behind intermediate portion  169 . Collapsible sheath  118  is desirably long enough to cover rearwardly facing tip  176  of fluid discharge needle  116  prior to use and is collapsed and pushed forward around needle  116  after tip  176  penetrates closed end  182  as it is inserted into the stoppered end of a blood collection tube. 
         [0039]    Referring to  FIGS. 3 and 6 , compressible fluid seal  112  is substantially cylindrical and has centrally disposed bore  166  that is coaxially aligned with the fluid flow path through needle holders  110 ,  114 . During assembly of body  102  of blood collection tube holder  100 , larger diameter head portion  164  is desirably pressured forwardly inside nose  138  of body  102  to compress spring  120 , and is held in nose  138  while the front end of compressible fluid seal  112  is inserted into nose  138  behind needle holder  110 . The rear end of compressible fluid seal  112 , which extends rearwardly from nose  138 , is then desirably compressed sufficiently to enable needle holder  114  to be slidably inserted into body  102  behind compressible fluid seal  112  to establish fluid-tight engagement between compressible fluid seal  112  and each of needle holders  110 ,  118 . The relative positions of nose  138 , needle holders  110 ,  114  compressible fluid seal  112  as assembled inside body  102  are better seen in  FIG. 6 . 
         [0040]    Referring to  FIG. 4 , like reference numerals are used to identify parts of blood collection tube holder  100  already discussed above in relation to  FIG. 3 . Additional structural elements not visible in  FIG. 3  include inside bore  153  of removable needle cap  106 , textured gripping surface  101  (visible in  FIG. 5  opposite textured gripping surface  103 ), and optional rearwardly facing projection  119  of discharge needle displacement member  104  that is aligned with aperture  131  when discharge needle displacement member  104  is installed inside body  102  as shown in  FIG. 6 . It should be understood that projection  119  and aperture  131  are merely illustrative of other similarly effective structures that can optionally provide releasable frictional engagement between the closed rear end of discharge needle displacement member  104  and outwardly projecting rear flange  134 . Where present, projection  119  and aperture  131  are desirably cooperatively sized and aligned to form a releasable frictional engagement mechanism that provides additional support to the rear end of discharge needle displacement member  104  prior to and during use of blood collection tube holder  100  to collect a blood sample. Projection  119  desirably remains in releasable engagement with aperture  131  until discharge needle displacement member  104  is moved into contact with needle holder  114  inside body  102  following withdrawal of a blood collection tube from cylindrical cavity  133  ( FIG. 6 ) inside body  102 . 
         [0041]    Referring to  FIGS. 5 and 6 , blood collection tube holder  100  of the invention as described in relation to  FIGS. 1, 3 and 4  is shown in fully assembled form with removable needle cap  106  installed as shown in  FIG. 1 , and with releasable locking arm  154  inserted into body  102 . When disposed in the position shown, releasable locking arm  154  supports and prevents the front portion of discharge needle displacement member  104  from being inadvertently moved further inwardly into body  102  during shipping and storage, and prior to removal of needle cap  102  prior to use. As depicted in  FIG. 6 , a continuous fluid flow path extends from venipuncture needle  108  thorough needle holder  110 , compressible fluid seal  112  and needle holder  114  to fluid discharge needle  116 , all of which are desirably coaxially aligned for use in drawing a blood sample after removal of needle cap  106  and insertion of a blood collection tube into blood collection tube holder  100 . 
         [0042]    Referring to  FIGS. 3, 4, 7 and 8 , structures are disclosed that are exemplary of a variety of different structures that can be used by one of ordinary skill in the art upon reading this disclosure to position and support discharge needle displacement member  104  relative to body  102  (as viewed from the rear through the opening defined by flange  134 ) even after releasable locking arm  154  is withdrawn from its locking position beneath discharge needle displacement member  104  following removal of needle cap  106 . Looking first at  FIGS. 4 and 7 , rearwardly facing projection  119  of needle retraction chamber  105  is aligned with and releasably inserted into a recess or aperture  131  of flange  134 . Looking next at detail view of  FIG. 8  with reference to  FIGS. 3, 4 and 7 , as discharge needle displacement member  104  is inserted into body  102 , free ends  194 ,  196  of arms  124 ,  126 , respectively, slide past inwardly facing tapered shoulders  190 ,  192  of guide members  144 ,  145  behind front portion  168  and beside intermediate portion  169  of needle holder  114  ( FIGS. 3 and 4 ) until the tapered portions of shoulders  135 ,  137  of arms  124 ,  126 , respectively, contact and rest against inwardly facing tapered shoulders  190 ,  192 .  FIGS. 7 and 8  indicate the resting position of discharge needle displacement member  104  relative to body  102  prior to and during use of the device to draw a blood sample. 
         [0043]    Referring to  FIGS. 9 and 10 , a transverse cross-sectional view is taken behind front wall  136  of body  102  to better illustrate the positions of discharge needle displacement member  104  and opening  128  into needle retraction chamber  105  relative to body  102  prior to and during use of the device but prior to retraction of the venipuncture needle. As best seen in  FIG. 10 , when support arms  109 ,  111  of discharge needle displacement member  104  are installed in body  102 , hook members  115 ,  117  disposed at the lower ends of support arms  111 ,  109 , respectively, are initially flexed inwardly and then pass opposing square shoulders in walls  202 ,  204  of guide structures  144 ,  145 , respectively, that permit movement in the direction of arrows  198 ,  200  (which movement is still restricted by the resistance imposed by tapered shoulders  190 ,  192  as discussed above in relation to  FIG. 8 ) but prevent movement in the opposite direction to disengage discharge needle displacement member  104  from body  102 .  FIGS. 11 and 12  disclose two additional orthogonal views of blood collection tube holder  100  with venipuncture needle  116  projecting forwardly from needle holder  110  and nose  138 , and with discharge needle displacement member installed in the use position relative to body  102 . Other reference numerals used in  FIGS. 11 and 12  are consistent with those previously described in relation to other drawing figures. 
         [0044]    Following use of blood collection tube holder  100 , as manual pressure is applied to textured touch surface  130  ( FIG. 7 ), free ends  194 ,  196  are squeezed together by the tapered surfaces of shoulders  135 ,  137  sliding downwardly past inwardly facing shoulders  190 ,  192  of guide structures  144 ,  145 , respectively. Once shoulders  135 ,  137  move past shoulders  190 ,  192 , the front portion of discharge needle displacement member  104  is no longer constrained in the pre-use and use position. The same manual force applied to textured touch surface  130  is desirably sufficient to overcome the frictional holding force between projection  119  and aperture  131 . This causes projection  119  to disengage from aperture  131  and allows both the front and rear portions of discharge needle displacement member  104  to move inwardly relative to body  102 . As this movement occurs, the front portion of discharge needle displacement member  104  contacts needle holder  114  ( FIG. 4 ) and displaces needle holder  114  and fluid discharge needle  116  laterally away from compressible fluid seal  112 , simultaneously disrupting the continuous fluid flow path that existed between venipuncture needle  108  and fluid discharge needle  116  ( FIG. 6 ) prior to the contact and displacement. 
         [0045]      FIGS. 13 and 14  depict cross-sectional views similar to those previously described in relation to  FIGS. 9 and 10  except that the section is taken through front portion  168  of needle holder  114  and the needle retraction process has been initiated. As shown, discharge needle displacement member  104  is moved out of engagement with aperture  131  in flange  134  of body  102 , and the front portion of discharge needle displacement member  104  is moved into contacting and abutting relation with the top of front portion  168  of needle holder  114 . From this position, continued application of manual pressure to textured touch surface  130  will force discharge needle displacement member  104  into the position shown in  FIGS. 15-18 , wherein venipuncture needle  108  is fully retracted inside body  102  of blood tube collection holder  100 , front portion  168  of needle holder  114  is disengaged from the rear end of compressible fluid seal  112 , and needle holder  114  and fluid discharge needle  116  are forced into the position best shown and further described below in relation to  FIGS. 19 and 20 . 
         [0046]    Referring to  FIGS. 19 and 20 , when discharge needle displacement member  104  is moved to the position shown, needle retraction chamber  105  becomes coaxially aligned with collapsible fluid seal  112 , needle holder  110  and venipuncture needle  108 , all of which are then propelled by expanding compression spring  120  into needle retraction chamber  105 . When disposed in this position, venipuncture needle  108  is no long exposed in a position where accidental needle stick injuries and related contamination by blood-borne pathogens can occur. This is particularly true if venipuncture needle  108  is retracted directly from the body of a patient as recommended. At the same time, needle holder  114  and fluid discharge needle  116 , together with any fluid remaining inside them, are confined between the back side of front wall  136  and the closed rear end  182  of collapsible elastomeric sheath  118  that is preferably substantially impermeable to any blood remaining inside fluid discharge needle  116 . 
         [0047]    Other alterations and modifications of the invention disclosed here will likewise become apparent to those of ordinary skill in the art upon reading this specification and claims in relation to the accompanying drawings, and the inventors intend that the scope of the invention be limited only by the broadest interpretation of the appended claims to which the inventors are legally entitled.