Patent Publication Number: US-2023149666-A1

Title: Safety catheter with passive release

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of U.S. application Ser. No. 16/717,063 filed Dec. 17, 2019 entitled “Safety Catheter with Passive Release.”. The &#39;063 application in turn is a continuation of U.S. application Ser. No. 16/065,578 filed Jun. 22, 2018, entitled “Safety Catheter with Passive Release.” The &#39;578 application is the National Stage Application of PCT/US2018/023550 filed Mar. 21, 2018, entitled “Safety Catheter with Passive Release.” The &#39;550 PCT claims priority to U.S. Provisional Application Ser. No. 62/475,428 filed Mar. 23, 2017 entitled “Safety Catheter with Passive Release.” Each of these references is incorporated herein by reference in their entirety for all purposes. 
    
    
     FIELD OF INVENTION 
     The present disclosure relates to a safety intravenous (IV) catheter and more particularly to a safety IV catheter that includes a passive release feature. 
     BACKGROUND OF INVENTION 
     Safety catheter assemblies typically include a catheter hub assembly and a catheter insertion device having an insertion needle. The catheter hub of the catheter hub assembly is assembled to the catheter insertion device (or insertion needle assembly) in a ready for use configuration with a catheter tube of the catheter hub positioned over the insertion needle and a sharp tip of the insertion needle protruding from a distal end of the catheter. A needle sheath may be positioned over the sharp tip of the insertion needle to prevent unwanted needle sticks prior to the safety catheter assembly being used. The overall safety catheter assembly, including the catheter hub assembly, catheter insertion device, and needle sheath, may be provided for use in a sterilized and assembled state, contained within a sealed package. One example of such a safety catheter assembly includes the JELCO INTUITIV (Trademark) safety catheter assembly marketed by Smiths Medical ASD, Inc. of Plymouth, Minn., as described in U.S. Pat. No. 8,257,322. 
     To insert the catheter into the vein of a subject, a clinician first removes the safety catheter assembly from the packaging. The needle sheath is removed to expose the sharp tip of the insertion needle that is protruding from the distal end of the catheter. The clinician punctures an identified site of a subject with the sharp needle tip and urges the insertion needle forward until the needle tip enters the vein of the subject. An initial amount of blood may pass through a lumen of the needle, entering the catheter and/or catheter insertion device where the clinician may view the “flashback” of the blood to confirm entry into the vein. The catheter may then be moved distally over the needle to thread the tube of the catheter into position in the vein of the subject. The needle may be held stationary during catheter threading. With the catheter positioned as desired, the clinician withdraws the needle by pulling the catheter insertion device proximally away from the subject while holding the catheter hub assembly generally stationary with respect to the subject. The insertion needle is pulled proximally until the needle and catheter insertion device are separated from the catheter hub. The clinician may dispose of the catheter insertion device in a sharps container, after the insertion device is separated from the catheter. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIGS.  1   a - 1   c    are perspective views, taken from a distal vantage, of an example embodiment of a safety catheter assembly in each of a ready position ( FIG.  1   a   ), a safe position ( FIG.  1   b   ) and a release position ( FIG.  1   c   ). 
         FIGS.  2   a - 2   c    are perspective views, taken from a proximal vantage, of the safety catheter assembly of  FIGS.  1   a - 1   c    in each of a ready position ( FIG.  2   a   ), a safe position ( FIG.  2   b   ) and a release position ( FIG.  2   c   ). 
         FIGS.  3   a - 3   d    are cross section views of the safety catheter assembly of  FIGS.  1   a - 2   c    in each of a ready position ( FIG.  3   a   ), a safe position ( FIG.  3   b   ) and a release position ( FIGS.  3   c  and  3   d   ). 
         FIGS.  4   a - 4   c    are perspective views, taken from a distal vantage, of the tip protector assembly of  FIGS.  1   a - 3   d    in each of a ready position ( FIG.  4   a   ), a safe position ( FIG.  4   b   ) and a release position ( FIG.  4   c   ). The catheter and needle are removed from  FIGS.  4   a - 4   c    for purposes of illustration. 
         FIG.  5    is a perspective view of an inner member of a tip protector assembly, according to one example embodiment. 
         FIG.  6    is a perspective view of an outer member of a tip protector assembly, according to one example embodiment. 
         FIG.  7    is a perspective view of a retainer of a tip protector assembly, according to one example embodiment. 
         FIG.  8    is a perspective view of another embodiment of the collar of a needle tip protector assembly that does not have an upright. 
         FIG.  9    is a perspective view of a catheter hub assembly that includes a side port. 
         FIG.  10    is a cross sectional view of the catheter hub shown in  FIG.  9   . 
     
    
    
     DETAILED DESCRIPTION OF INVENTION 
     Safety catheter assemblies, according to various example embodiments disclosed herein, may be positioned during use in a ready for use position, a safe and engaged position, and a safe and released position. In the ready for use (referred to herein as the “ready position”), the catheter hub assembly is assembled to the catheter insertion device with the sharp tip of the insertion needle protruding from a distal end of the catheter tube and the catheter hub secured to the catheter insertion device in a manner that prevents the catheter hub assembly and the catheter insertion device from being removed from each other. In the safe and engaged position (referred to herein as the “safe position”) the sharp tip of the insertion needle is positioned in a tip protector of the catheter insertion device in order to prevent access to the needle that might otherwise result in unwanted needle sticks. The catheter hub assembly remains secured to the catheter insertion device when in the safe and engaged position. In the safe and released position (referred to herein as the “release position”) the catheter hub is disengaged from the catheter insertion device so that the insertion device may be separated from the catheter hub assembly and be disposed of in a safe manner. The sharp tip of the insertion needle remains inaccessible in the release position to prevent unwanted needle sticks. 
     Turn now to the figures.  FIGS.  1   a  to  3   d    show an example embodiment of a safety catheter assembly  100  that includes a catheter hub assembly  200 , an insertion needle assembly  300 , and a needle tip protector assembly  400 . The catheter hub assembly  200 , insertion needle assembly  300 , and needle tip protector assembly  400  are shown in each of the ready position ( FIGS.  1   a ,  2   a , and  3   a   ), the safe position ( FIGS.  1   b ,  2   b , and  3   b   ), and the release position ( FIGS.  1   c ,  2   c ,  3   c , and  3   d   ), according to one example embodiment.  FIGS.  1   a - 1   c  and  2   a - 2   c    show the safety catheter assembly  100  in respective distal and proximal views.  FIGS.  3   a - 3   d    are cross sectional views of a substantial portion of the safety catheter assembly. 
     The catheter hub assembly  200  includes a catheter hub  202  and a catheter tube, or simply catheter  204  that cooperate to provide a fluid pathway between the vein of a subject and other IV fluid components, such as an IV fluid supply. The catheter  204  includes a distal end, a proximal end, and a lumen extending therebetween. The proximal end of the catheter  204  is connected to a distal portion of the catheter hub  202 . The proximal end  206  of the catheter hub is constructed and arranged to connect to other IV fluid components and may be designed in accordance with ISO standards. In the illustrated example embodiment, the proximal end of the catheter hub includes luer lugs, although other constructions are also contemplated. 
     The insertion needle assembly  300  includes an insertion needle  302  having a sharp distal tip  304  that may create an entry passageway into the vein of a subject, as the needle slidably extends through the catheter with its distal tip extending beyond the distal end of the catheter when the catheter assembly is in the ready to use position. The insertion needle extends from the sharp distal tip  304  to a proximal portion that is connected to a needle hub  306 , and defines an internal lumen that extends therebetween. The proximal portion of the insertion needle is connected to and in fluid communication with the needle hub  306 . The needle hub, in turn, is connected to the flash plug  308  to allow blood to flow from the needle tip  304  to the flash plug. The flash plug  308  may include a microporous barrier that permits the escape of air but prevents the escape of fluid. The body of the insertion needle may include a transition or bump  310  proximal the sharp distal tip that interacts with the needle tip protector to move the safety catheter assembly between the ready, safe, and released positions. 
     The illustrated example embodiment also includes a needle tip protector  400 . The needle tip protector  400  includes an inner member  402 , an outer member  404 , a retainer  406 , and a collar  408 , each of which is shown separately in  FIGS.  5  to  8   . The inner member  402  and the outer member  404  of the needle tip protector  400  cooperate to prevent access to the needle tip  304  in the safe and released positions. Additionally, the retainer  406  and the collar  408  cooperate to secure the catheter hub assembly  200  to the needle tip protector  400  in each of the ready and safe positions, while enabling the needle tip protector  400  to be released from the catheter hub  202  in the release position. 
     The transition or bump  310  on the body of the needle  302  acts to move the needle tip protector  400  between the ready, safe, and release positions and may also prevent separation of the insertion needle assembly  300  from the tip protector assembly  400 . The inner member  402  of the tip protector  404  includes distal arms  410 , a proximal base  412 , and a bump washer  414 . The bump washer  414  defines a proximal opening  418  that allows passage of the needle  302  and a proximal needle stop  416  that prevents bump  310  from passing. When insertion needle  302  is pulled proximally between the ready and safe positions, the proximal needle stop  416  would prevent the transition  310  from passing through the proximal opening  418 , thus preventing the tip protector  400  from separating from the needle assembly  300 . 
     In the illustrated embodiment, the proximal needle stop  416  is formed in a bump washer  414  that is assembled to the proximal end of the inner member  402 . The bump washer  414  is shaped generally like a traditional washer with the inclusion of a distally extending arm  420  that facilitates connection to other portions of the inner member. The bump washer may be made of a rigid material, such as a metal or plastic that resists deformation when contacted by the transition of the insertion needle. It is to be appreciated that proximal stops, according to alternate example embodiments, may be formed directly in the retainer or in different types of bump washers, such as bump washers that lack a distally extending tab or that are made of materials other than metal. 
     The transition  310  may be located on the needle  302  so that the needle tip  304  is positioned within the inner member  402  of the tip protector  400  when the transition contacts the proximal stop  416 , such that access to the needle tip may be prevented. This may generally be accomplished by locating the transition  310  a distance from the needle tip  304  that is less than the distance between the proximal stop  416  and the distal end  422  of the inner member  402 . According to some embodiments, the distance between the transition and the needle tip may be smaller than a distance between the proximal stop and a distal stop on the inner member. It is to be appreciated, however, that other configurations are possible, including embodiments where the transition is located on the needle such that the needle tip is positioned internally to the outer member or another component of the tip protector. 
     Further proximal movement of the insertion needle  302 , once the transition  310  is in contact with the proximal stop  416 , causes the inner member  402  to move proximally relative to the outer member  404  from a distal inner member position to a proximal inner member position, as may be seen in the progression of movement between  FIGS.  3   a  and  3   b   . Movement of the inner member  402  within the outer member  404  causes arms  410  of the inner member to move into a restriction  424  of the outer member. Interaction between the arms  410  and the outer member  424  urges the arms toward one another, causes the arms to form a distal needle stop  426  in the passageway previously occupied by the insertion needle  302 . The distal needle stop  426  prevents distal movement of the needle from outside of the interior of the inner member, and thus protects clinicians and others from the sharp needle tip. 
     The arms of the inner member may include protrusions or ribs that engage one another to form the distal needle stop when the inner member is in the proximal inner member position, such as when the tip protector assembly is in either of the safe or release positions. These or other features of the arms may contact one another, fully occupying the needle passageway to form the distal needle stop, as shown in  FIG.  3   b   . It is to be appreciated, however, that other embodiments may lack such fingers or ribs. It is also to be appreciated that the distal needle stop may not fully occupy the needle passageway when in the safe position, according to alternate embodiments. In one such alternate embodiment, the arms of the inner member are urged toward one another to form a distal needle stop that restricts passage of the sharp needle tip without fully occupying the needle passageway. 
     The distal arms  410  of the inner member may be biased in the radially outward direction, away from one another. Such a bias may promote separation of the distal arms  410  from one another and thus from the insertion needle  302  prior to the needle reaching the safe position. Such separation may minimize friction between the insertion needle  302  and inner member  402 , promoting easy movement of the insertion needle from the ready position to the safe position. According to some embodiments, the inner member is made of a resilient rubber or plastic material. 
     The distal arms  410  may include a hinge area  428  near a connection to the proximal base  412  and an enlarged distal portion  430 . The hinge area may promote flexing of the distal arms between the ready position and the safe position. The enlarged distal portions  430  may be shaped and sized to form the distal needle stop  426  when moved inwards or toward one another by the restriction  424  of the outer member. In the illustrated embodiment, the distal portion of at least one of the arms includes a ramp structure  432  that interacts with the outer member  404  to urge the arm inward  410 , toward the needle passageway, as the inner member is pulled proximally by movement of the insertion needle. 
     The inner member includes a safe position lock  434  that prevents distal movement of the inner member, once in the inner member proximal position relative to the outer member. In the illustrated example embodiment, the lock  434  includes a distally facing inner member lock surface  436  that interacts with an inwardly biased tab  438  of the outer member  404 . Proximal movement of the inner member  402  brings the lock surface into engagement with a proximally facing lock surface of the tab  438 . Once engaged, the lock surfaces  436  of the inner member  402  and the tab  438  prevent emergence of the needle tip  304  by preventing the inner member  402  from returning to the distal inner member position. It is to be appreciated that the safe position lock shown in the illustrated example embodiment is but one type of lock and that others are also contemplated. 
     As may be seen in  FIGS.  3   a  and  3   b   , in each of the ready and safe positions the catheter hub assembly  200  is secured to the needle tip protector assembly  400  in a manner that prevents separation, with the retainer  406  in a distal retainer position relative to the collar  408 . This is accomplished by various engagement features in the needle tip protector assembly  400  that secure the catheter hub assembly  200  to the needle tip protector assembly  400  until the needle tip protector assembly  400  is in the release position. In the illustrated embodiment, external engagement features are located on the collar and the retainer. The outer member  404  of the needle tip protector may additionally provide internal engagement features that help to secure the catheter hub assembly  200  to the needle tip protector assembly  400 . 
     As shown in  FIGS.  1   a - 1   c  to  4   a - 4   c   , collar  408  has a distal portion  408   a  and a proximal portion  408   b . Collar distal portion  408   a  forms a chamber  408   e  that has a larger circumferential dimension than a chamber  408   f  formed at collar proximal portion  408   b . Distal chamber  408   e  has a larger circumferential dimension than proximal chamber  408   f . A notch  440  at the distal open end or formed along the inner wall in distal chamber  408   e  is configured to receive at least one luer lug  208  of the catheter hub  202 . The notch  440  engages the luer lug to prevent the luer lug and thus the catheter hub  202  from moving distally away from the needle tip protector assembly  400 . Contact between the notch and the luer lug of the catheter hub may also prevent the catheter hub assembly  200  from moving laterally away from the needle tip protector assembly  400 . As further shown in  FIGS.  1   a - 1   c  to  4   a - 4   c   , the distal portion  408   a  of collar  408  has an upright  408   c  that extends upwardly from the top of the distal portion  408   a . Upright  408   a  has a distal front surface  408   c   1  that is flush with the distal end  408   d  of distal portion  408   a  of collar  408  and a proximal back surface  408   c   2  onto which a clinician may push against. 
     External engagement features are provided by the retainer  406 . The retainer  406  includes a base  406   a  having a through bore  406   b  for receiving the proximal end portion  452  of the outer member  404  of the needle tip protector and a distal extension  406   c  that has a lateral wall  406   d . The internal wall surface  406   d   1  of lateral wall  406   d  forms a pocket or internal cavity  406   e  adapted to receive the proximal end  206  of the catheter hub  202 . Inner portions of the collar  408  of the needle tip protector assembly  400  engage corresponding outer surfaces of the catheter hub to secure the catheter hub assembly  200  to the needle tip protector assembly  400 . 
     The outer member of the needle tip protector assembly may contact the interior of the catheter hub to provide an interior engagement. As shown in  FIGS.  3   a - 3   d   , an internal engagement feature of outer member  404  is provided by a distal upraised end portion  437  of the restriction  424 . As shown in  FIG.  3   a   , when the needle  302  is at the ready position, the arms  410  of the inner member  402  are biased away from each other by the needle passing therebetween such that the distal upraised end portion  437  comes into abutment contact with an internal shoulder  435  at the catheter hub  202  to prevent proximal movement of the needle tip protector relative to the catheter hub  202 . As the needle  302  is retracted proximally and its transition  310  comes into contact with the bump washer  414  at the outer member  404 , further proximal movement of the needle pulls the distal tip of the needle into the inner member  402  with the arms  410  of the inner member  402  collapsing toward each other due to the sliding surfaces of their respective ramps  432  being biased by the corresponding restrictions  424  at the outer member  404 , as per shown in  FIG.  3   b   , such that the distal tip  304  of the needle  302  is non-removably captured in the inner member  402 . With the collapsing of the arms  410 , the respective distal upraised end portions  437  of the restrictions  424  at the outer member  404  are no longer biased into abutment contact with the internal shoulder  435 . As a result, the outer member  404  is no longer in fixed engagement with the catheter hub  202 . Further proximal movement of the needle moves the retainer  406  from a first or distal position ( FIG.  3   a   ) to a second or proximal position ( FIG.  3   b   ) in the proximal chamber  408   f  of collar  408  to enable the collar  408  and the catheter hub  202  to disengage from each other.  FIG.  3   d    shows the needle tip protector assembly  400  and the catheter hub assembly  200  separated from each other when the distal portion  408   a  of the collar  408  is disengaged from the proximal end of the catheter hub  202 . 
     With the needle tip protector assembly  400  in the safe position and the inner member  402  in contact with the proximal wall of the outer member  404 , further proximal movement of the insertion needle  302  causes the retainer  406 , and other components of the needle tip protector assembly  400 , to move proximally relative to the collar  408  to a proximal retainer position. This motion causes external engagement features of the retainer  406  to move proximally away from the corresponding outer surfaces of the catheter hub  202 , as shown in the progression of movement between  FIGS.  3   b  and  3   c   . The sliding surface of the outer member  404  is also moved proximally and out of contact with the inner surface of the catheter hub  202 , at least in embodiments that include contact between the catheter hub  202  and inner member  402 . 
     The needle tip protector assembly  400  may include a feature that resists proximal movement of the retainer  406  to the proximal release position prior to being in the safe position. The illustrated example embodiment includes a retention finger  450  that is integrated into the enlarged distal portion  408   a  of collar  408  and that includes a spring arm and a retention tab  442 . The retention tab is positioned distally to the main portion of retainer  406 . Proximal movement of the retainer  406  is resisted by the retention tab and its finger  450  such that a given force in the proximal direction of moving retainer  406  relative to collar  408  is needed to overcome the resistance provided by the retention tab  442  and its finger  450 . In this respect, the retention tab  442  and its finger  450  of the collar  408  provide a release threshold force that is to be overcome prior to the catheter hub assembly  200  being released from the needle tip protection assembly  400 . 
     The release threshold force may be higher than the forces associated with movement from the ready position to the safe position (i.e., the safety threshold force), according to some embodiments. Having the release threshold force higher than the safe threshold force may prevent the catheter from being released prior to the tip protection assembly being moved to the safe position. The release threshold force, according to some embodiments, is more than 2× the safety threshold force, more than 3× the safety threshold force, or more than 5× the safety threshold force. 
     The catheter hub  202  is released from secure connection to the tip protection assembly  400  when the external engagement features of the retainer  406  are out of engagement with the catheter hub  202 , as shown in  FIG.  3   c   . In this position, the further proximal movement of the insertion needle assembly  300  will pull the needle tip protector  400  away from the catheter hub  202 , as reflected in  FIG.  3   d   . Separation of the collar  408  from the catheter hub  202  may be accompanied by a slight jogging of the tip protector in a lateral direction, away from the needle passage, according to some embodiments. The sloped shape of the luer lug and/or the notch may promote this motion. Additionally, or alternately, the clinician may tilt pull on the insertion needle assembly at an upward angle to promote separation of the catheter from the collar. 
     The catheter hub may include a side port  500 , such as in the example embodiment of  FIGS.  9  and  10   . As shown, the catheter hub  202  includes a side port that may be accessed through a lateral, luer type connection that is integrated into the catheter hub. A side port cap  502  may be selectively positioned over the side port to close and open access thereto, as desired. A flexible, cylindrically shaped septum is positioned internally to the catheter hub. The septum  504  is moved away from the side port by pressurized fluid that is introduced into the luer to allow the pressurized fluid to enter the catheter hub. In the absence of pressurized fluid in the luer, the septum closes access to the side port to prevent the escape of fluids from the catheter. 
     Various example embodiments of catheters are described herein for use in accessing the vein of a subject. It is to be appreciated, however, that the example embodiments described herein may alternately be used to access the vasculature of a subject at locations other than a vein, including but not limited to the artery of a subject. It is additionally to be appreciated that the term “clinician” refers to any individual that may be performing a catheter insertion procedure with any of the example embodiments described herein or combinations thereof. Similarly, the term “subject”, as used herein, is to be understood to refer to an individual or object in which a catheter is to be inserted, whether human, animal, or inanimate. Various descriptions are made herein, for the sake of convenience, with respect to procedures being performed by a clinician to access the vein of a subject, while the disclosure is not limited in this respect. 
     It is also to be appreciated that the term “distal”, as used herein, refers to the direction, taking along an axis that lies parallel to the needle of a safety catheter assembly that is closest to a subject during catheter insertion. Conversely, the term “proximal”, as used herein, refers the direction lying along the axis parallel to the needle that is farther away from the subject when the catheter is inserted into the vein of the subject—that is, opposite to the distal direction. 
     The foregoing description of example embodiments has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed. Many modifications and variations are possible in light of this disclosure. It is intended that the scope of the present disclosure be limited not by this detailed description, but rather by the claims appended hereto. Future-filed applications claiming priority to this application may claim the disclosed subject matter in a different manner and generally may include any set of one or more features as variously disclosed or otherwise demonstrated herein.