Patent Publication Number: US-2023134015-A1

Title: Flexible Shield for Reducing Tubing Buckling in Blood Collection Device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to U.S. Provisional Application Ser. No. 63/273,252, entitled “Flexible Shield for Reducing Tubing Buckling in Blood Collection Device”, filed Oct. 29, 2021, the entire disclosure of which is hereby incorporated by reference in its&#39; entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present disclosure relates generally to medical devices for use with intravenous (IV) catheters and, more specifically, to medical devices with features for limiting deflection of flexible catheters. 
     Description of Related Art 
     Blood collection devices, when used with indwelling IV catheters, can include displaceable catheters that are advanced beyond the tip of the indwelling catheter for blood collection. Often, when the displaceable catheter is advanced, it can encounter an obstruction, resulting in deflection of the catheter. Examples of obstructions include the friction of the seal within the blood collection device, torturous path within an integrated catheter, pinching of the catheter tubing as it dives into the skin, thrombus, fibrin, and valves. Such deflections can reduce the ability of the displaceable catheter to extend beyond the tip of the indwelling catheter, and thus limits their use for blood collection. Accordingly, a need exists in the art for devices that limit buckling, and that ensure timely and effective blood collection. 
     SUMMARY OF THE INVENTION 
     Provided herein is a medical device, including a catheter having a proximal end, a distal end, and a sidewall therebetween defining a lumen therethrough, an introducer having a proximal end, a distal end, and a sidewall therebetween defining an inner volume configured to movably receive the catheter, the distal end of the introducer having a lock configured to couple the introducer to an intravenous line, the introducer further having a flexible member arranged within the inner volume configured to limit deflection of the catheter as the catheter is moved within the introducer, and an actuator movably coupled to the introducer, the actuator having a first portion disposed outside of the introducer and a second portion disposed in the inner volume of the introducer and coupled to the catheter, the actuator configured to move relative to the introducer to move the catheter between a first position, in which the catheter is disposed within the introducer, and a second position, in which the distal end of the catheter is disposed beyond the distal end of the introducer such that at least a first portion of the catheter is disposed within the intravenous line when the introducer is coupled to the intravenous line. 
     In certain configurations, the flexible member is arranged along a longitudinal axis within the inner volume of the introducer. The flexible member may include an elastomeric material. In certain configurations, the flexible member and the introducer define a substantially cylindrical passage within which the catheter is received. The flexible member may extend from the proximal end of the introducer to the distal end. 
     In certain configurations, the flexible member is a unitary member. In other configurations, the flexible member may include a plurality of flexible members. The plurality of flexible members may be arranged about a perimeter of the inner volume. The plurality of flexible members may substantially surround the catheter. 
     In other configurations, as the actuator is moved toward the distal end of the introducer, the second portion of the actuator displaces the flexible member. The second portion of the actuator may be coupled to the proximal end of the catheter. In still other configurations, a lubricant may be received within the inner volume. 
     Also provided herein is a medical device, including a catheter having a proximal end, a distal end, and a sidewall therebetween defining a lumen therethrough, an introducer having a proximal end, a distal end, and a sidewall therebetween defining an inner volume configured to movably receive the catheter, the distal end of the introducer having a lock configured to couple the introducer to an intravenous line, the introducer further having a flexible member arranged within the inner volume, and an actuator coupled to the catheter, the actuator configured to move relative to the introducer in response to a first force exerted on the actuator to move the catheter between a first position, in which the distal end of the catheter is disposed within the lumen of the lock, and a second position, in which the catheter extends through the lock and intravenous line when the lock is coupled to the intravenous line such that the distal end of the catheter is disposed within the intravenous line, wherein the actuator is configured to exert a second force different from the first force on the proximal end of the catheter as the actuator moves the catheter from the first position to the second position, the second force resulting in a deflection of a portion of the catheter disposed between the actuator and the lock as the actuator moves the catheter from the first position to the second position, and wherein the flexible member is configured to limit the deflection. 
     In certain configurations, the actuator includes a first portion disposed outside of the introducer and a second portion disposed within the introducer, and the first force exerted on the actuator is exerted on the first portion of the actuator, the second force exerted by the actuator is exerted by the second portion of the actuator. The flexible member may be arranged along a longitudinal axis within the inner volume of the introducer. Optionally, the flexible member may include an elastomeric material. 
     In certain configurations, the flexible member and the introducer may define a substantially cylindrical passage within which the catheter is received. The flexible member may extend from the proximal end of the introducer to the distal end. The flexible member may be a unitary member. In certain configurations, the flexible member may include a plurality of flexible members. Optionally, the plurality of flexible members may be arranged about a perimeter of the inner volume. In other configurations, the plurality of flexible members may substantially surround the catheter. 
     In certain configurations, as the actuator is moved toward the distal end of the introducer, the second portion of the actuator displaces the flexible member. The second portion of the actuator may be coupled to the proximal end of the catheter. The device may further include a lubricant received within the inner volume. 
     Also provided herein is a medical device, including a catheter having a proximal end, a distal end, and a sidewall therebetween defining a lumen therethrough, an introducer having a proximal end, a distal end, and a sidewall therebetween defining an inner volume configured to movably receive the catheter, the distal end of the introducer having a lock configured to couple the introducer to an intravenous line, the inner volume configured to limit deflection of the catheter as the catheter is moved within the introducer, an actuator movably coupled to the introducer, the actuator having a first portion disposed outside of the introducer and a second portion disposed in the inner volume of the introducer and coupled to the catheter, the actuator configured to move relative to the introducer to move the catheter between a first position, in which the catheter is disposed within the introducer, and a second position, in which the distal end of the catheter is disposed beyond the distal end of the introducer such that at least a first portion of the catheter is disposed within the intravenous line when the introducer is coupled to the intravenous line. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of a medical device according to non-limiting embodiments described herein; 
         FIG.  2    is an exploded perspective view of a medical device according to non-limiting embodiments described herein; 
         FIG.  3    is an exploded perspective view of a medical device according to non-limiting embodiments described herein; 
         FIG.  4    is an exploded perspective view of a medical device according to non-limiting embodiments described herein; 
         FIG.  5    is a cross-sectional view of a prior medical device; 
         FIG.  6    is a cross-sectional view of a medical device according to non-limiting embodiments described herein; 
         FIG.  7    is a cross-sectional view of a medical device according to non-limiting embodiments described herein; 
         FIG.  8    is a front view of an actuator for a medical device according to non-limiting embodiments described herein; 
         FIG.  9    is a cross-sectional view of a medical device according to non-limiting embodiments described herein; 
         FIG.  10    is a cross-sectional view of a medical device according to non-limiting embodiments described herein; 
         FIG.  11    is a cross-sectional view of a medical device according to non-limiting embodiments described herein; 
         FIG.  12 A  is a cross-sectional view of a prior medical device; and 
         FIG.  12 B  is a cross-sectional view of a medical device according to non-limiting embodiments described herein. 
     
    
    
     DESCRIPTION OF THE INVENTION 
     The following description is provided to enable those skilled in the art to make and use the described embodiments contemplated for carrying out the invention. Various modifications, equivalents, variations, and alternatives, however, will remain readily apparent to those skilled in the art. Any and all such modifications, variations, equivalents, and alternatives are intended to fall within the spirit and scope of the present invention. 
     For purposes of the description hereinafter, the terms “upper”, “lower”, “right”, “left”, “vertical”, “horizontal”, “top”, “bottom”, “lateral”, “longitudinal”, and derivatives thereof shall relate to the invention as it is oriented in the drawing figures. However, it is to be understood that the invention may assume various alternative variations, except where expressly specified to the contrary. It is also to be understood that the specific devices illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the invention. Hence, specific dimensions and other physical characteristics related to the embodiments disclosed herein are not to be considered as limiting. 
     It should be understood that any numerical range recited herein is intended to include all values and sub-ranges subsumed therein. For example, a range of “1 to 10” is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10. 
     U.S. Pat. No. 11,090,461, which discloses medical devices including fluid transfer devices, is incorporated by reference herein in its entirety. 
     Provided herein is a medical device with a displaceable medical implement, such as a displaceable catheter. Exemplary medical devices include those utilized for blood collection from indwelling IV catheters, such as peripheral IV catheters, and have displaceable catheters that can be displaced such that a tip of the displaceable catheter extends beyond a tip of the indwelling IV catheter. In some instances, the displaceable catheter can encounter a resistive force, whether in the form of an occlusion at the tip of the indwelling IV catheter, a thrombus within the blood vessel, friction within the medical device, pinching of the catheter as the catheter curves to match the angle at which the IV catheter enters the patient&#39;s skin, or combinations thereof. Such resistive forces can result in deflection (e.g., buckling) of the displaceable catheter. Accordingly, devices as described herein include features for limiting deflection of displaceable implements (e.g., catheters) in medical devices. 
     Turning to  FIGS.  1 - 4   , shown is a non-limiting embodiment of a medical device  100 . While exemplified as a fluid transfer device, those of skill in the art will appreciate that the deflection-limiting features described herein will be suitable for any medical device with a displaceable implement that is subject to deflection, for example flexible, displaceable components. In the illustrated non-limiting embodiment, medical device  100  includes an introducer  110  having a distal end  112  and a proximal end  114 , with a sidewall  116  therebetween defining an inner volume  118 . As shown in  FIGS.  6 - 12   , inner volume  118  may include a first portion  118   a  and a second portion  118   b , which may or may not be fluidly isolated from one another. Introducer  110  may include, at distal end  112  thereof, a lock  130  and blunt cannula  132 , for coupling to an IV catheter (not shown), a catheter adapter (not shown), or the like. Introducer  110  may be any suitable size and/or shape, and may be formed of any suitable material(s), such as plastic(s). While lock  130  is exemplified in the present figures as a plurality of arms and blunt cannula  132 , those of skill will appreciate that any connection or coupling, for example a luer, can be used, so long as distal end  152  of catheter  150  may pass through the connection to access a medical device, such as an IV catheter to which introducer  110  is coupled. 
     With reference to  FIGS.  2 - 4   , introducer  110  may be formed of two housing portions, a first housing portion  120  and a second housing  122 . First and second housing portions  120 ,  122  can be coupled together by any suitable method, for example a snap fit, friction fit, ultrasonic weld, and/or adhesive. Combined housing portions  120 ,  122  may define inner volume  118 , and one or more features on interior surfaces of housing portions  120 ,  122  may define first and second inner volume portions  118   a,    118   b.    
     Medical device  100  may further include one or more catheters. In the non-limiting embodiments illustrated in the attached drawings, medical device  100  includes a catheter  150  and, optionally, a secondary catheter  160 . Secondary catheter  160  may be used to couple with, for example through coupler  170 , a vacuum (air or liquid) source, a blood collection tube, a fluid reservoir, fluid source, syringe, and/or the like, which in turn, may place the catheter  150  in fluid communication therewith. Those of skill in the art will appreciate that multiple catheters need not be employed (e.g., a coupler, such as coupler  170 , may be provided on proximal end  114  of introducer  110 ). 
     Catheter  150  may have a distal end  152 , proximal end  154 , and a sidewall  156  therebetween defining a lumen therethrough. Catheter  150  may be of any suitable length and gauge, and may be formed of any suitable material in any suitable configuration (e.g., braiding). In non-limiting embodiments, catheter  150  is from 10-30 gauge, all values and subranges therebetween inclusive. In non-limiting embodiments, catheter  150  may be formed of a relatively flexible biocompatible material with a Shore durometer of about 20 Shore A to 50 Shore D; about 20 Shore A to 95 Shore D; about 70 Shore D to 85 Shore D, and/or any other suitable range of Shore durometer. In some embodiments, at least a portion of catheter  150  may be formed of a braided material or the like, which can modify, change, and/or alter a flexibility of catheter  150  in response to a bending force or the like. In non-limiting embodiments, catheter  150  is formed of a polyimide-containing material. In non-limiting embodiments, catheter  150  is of a pre-determined length such that, when fully displaced distally, distal end  152  extends beyond a distal end of an IV catheter. In non-limiting embodiments, the predetermined length may be indicated by one or more indicia on introducer  110 . 
     Secondary catheter  160  may have a distal end  162 , proximal end  164 , and a sidewall  166  defining a secondary lumen therethrough. As noted above, secondary catheter  160  may include a coupler  170  at proximal end  164  thereof. Coupler  170  may be any suitable connection or coupler, for example a luer, a needleless connector, or like connector known to those of skill in the art. Secondary catheter  160  may be of any suitable length and gauge, and may be formed of any suitable material in any suitable configuration (e.g., braiding). In non-limiting embodiments, secondary catheter  160  is from  10 - 30  gauge, all values and subranges therebetween inclusive. In non-limiting embodiments, secondary catheter  160  is a polyimide-containing material. In non-limiting embodiments, secondary catheter  160  is in fluid communication with catheter  150 . In non-limiting embodiments, catheter  150  and secondary catheter  160  are configured to place a fluid reservoir, such as a blood collection tube (e.g., an evacuated tube) in fluid communication with the IV catheter, thus allowing for blood to be collected from the IV catheter. 
     Medical device  100  may also include an actuator  180 , which may be coupled to catheter  150 . In non-limiting embodiments, actuator  180  is coupled to proximal end  154  of catheter  150 . Actuator  180  may be manipulated by a user, such as a medical professional, to transition the device  100  from a first configuration, in which distal end  152  of catheter  150  is proximal of the IV catheter, to a second configuration in which at least distal end  152  of catheter  150  is disposed in a distal position relative to the IV catheter. With reference to  FIG.  8   , shown is a non-limiting embodiment of actuator  180 , in which actuator  180  includes a first portion  181  having an engagement member  182  and tab  183 , second portion  185  including opening  186 , and wall  187  therebetween. Engagement member  182  may be configured to be contacted by a finger of a user. Wall  187  may connect first portion  181  and second portion  185 . As can be appreciated from the attached drawings, inner volume  118  of introducer  110  can have a tortuous cross-sectional shape. Wall  187  may be configured to match such a tortuous shape. Opening  186  may be included in second portion  185 , and may be coupled with catheter  150  at any position along a length thereof. Coupling between catheter  150  and opening  186  may be accomplished through any known means, for example friction fit, ultrasonic weld, adhesives, or combinations thereof. Tab  183  may include one or more features that interact with an outer surface of introducer  100 , for example, to provide tactile, acoustic, and/or visual feedback. Such feedback can inform a user, for example, of how far catheter  150  has been displaced, including whether distal end  152  of catheter  150  is in a distal position relative to the IV catheter. 
     In non-limiting embodiments, in use, a first force is exerted on actuator  180  by a user to move actuator  180  relative to introducer  110  to advance catheter  150  from a first position, in which distal end  152  of catheter  150  is disposed within a lumen defined by lock  130 , toward a second position. A second force, different from the first force, is exerted by actuator  180 , for example by virtue of interaction between second actuator portion  185  and catheter  150 , on catheter  150 , for example on proximal end  154  of catheter  150 , as actuator  180  is advanced, displacing catheter  150  from the first position toward the second position. 
     As shown in  FIG.  5   , in prior devices  200 , catheter  250  may be deflected if catheter  250  encounters an obstruction during deployment by actuator  280  and/or if there is friction between catheter  250  and any portion of device  200 , as described previously. This deflection can increase beyond an acceptable amount, resulting in an inability to move distal end of catheter  250  to the second position (a distal position relative to the IV catheter). As shown in  FIGS.  2 - 4 ,  6 ,  7 , and  9   , introducer  110  of medical device  100  may include a flexible member  124  arranged within inner volume  118  to limit deflection of catheter  150 . Without wishing to be bound by the theory, it is believed that reducing the volume in which catheter  150  resides allows for an increase in force that can be applied to catheter  150 , to bypass occlusions or blockages without an unacceptable level of deflection being exhibited. 
     Flexible member  124  may be connected to introducer  110  through a snap fit, friction fit, ultrasonic weld, adhesives, or combinations thereof. Flexible member  124  may be arranged within introducer  110  in any suitable configuration, so long it serves to limit deflection of catheter  150 . In non-limiting embodiments, flexible member  124  extends along a substantial (e.g., more than  50 %) length of introducer  110 . In some embodiments, flexible member  124  extends along the complete length of the inner volume  118  of introducer  110 . In some embodiments, flexible member  124  may mark a separation between inner volume first portion  118   a  and inner volume second portion  118   b . Flexible member  124  may be formed of any suitable material. In non-limiting embodiments, flexible member  124  is formed of a material that allows flexible member  124  to maintain sufficient flexibility to allow flexible member  124  to be displaced by actuator  180  (e.g., wall  187 ) as actuator moves catheter  150  through inner volume  118 . In non-limiting embodiments, flexible member  124  is formed of a material with sufficient resiliency such that flexible member  124  returns to its original configuration following transit of actuator  180 , thereby maintaining a barrier that limits deflection of catheter  150  within inner volume  118 . 
     With regard to  FIG.  2   , while flexible member  124  is shown as being connected to and/or part of first introducer housing portion  120 , those of skill in the art will appreciate that flexible member  124  may be connected to one or both housing portions  120 ,  122 , and may assume any orientation/angle relative thereto, so long as flexible member  124  limits deflection of catheter  150 . For example, as shown in  FIGS.  7  and  9   , flexible member  124  may be oriented in a number of distinct ways in terms of angle and connection to one or more housing portions, and may, in some embodiments, form a border within inner volume  118 , providing an inner volume second portion  118   b  that provides catheter  150  with less space than a total space of inner volume  118  within which deflection can occur. 
     Turning to  FIGS.  10  and  11   , shown is a non-limiting embodiment of a medical device  300 . As described above, medical device  300  may include introducer  310 , catheter  350 , and actuator  380 . Introducer may include a plurality of housing portions, such as first housing portion (not shown) and a second housing portion  322  defining an inner volume, optionally an inner volume including first inner volume portion  318   a  and second inner volume portion  318   b . Actuator  380  may include a first portion  381 , second portion  385 , and wall  387  connecting first portion  381  and second portion  385 . While not shown, medical device  300  may also include one or more features described in other embodiments, for example a secondary catheter and a lock (optionally with a blunt cannula) at distal end thereof. 
     In the non-limiting embodiments of  FIGS.  10  and  11   , medical device  300  further may include a plurality of flexible members, in the form of flexible fibers  324 . Flexible fibers  324  may be connected with introducer  310  through friction fit, ultrasonic weld, adhesives, or combinations thereof. Flexible fibers  324  may be formed of any suitable material capable of limiting deflection of catheter  350 . In non-limiting embodiments, flexible fibers  324  are formed of a silicone-containing material. In non-limiting embodiments, flexible fibers  324  are arranged within inner volume of introducer  310 , for example in second inner volume  318   b , in any suitable angular orientation. In non-limiting embodiments, flexible fibers  324  are arranged substantially about a perimeter (e.g., circumference) of second inner volume portion  318   b . In non-limiting embodiments, flexible fibers  324  are arranged within second inner volume portion  318   b  in a manner that substantially or completely surrounds catheter  350 . As with other embodiments of flexible member disclosed herein, plurality of flexible fibers  324  may be formed of a material that allows flexible fibers  324  to maintain sufficient flexibility to allow flexible fibers  324  to be displaced by actuator  380  (e.g., wall  387 ) as actuator moves catheter  350  through inner volume of introducer  310 . In non-limiting embodiments, flexible fibers  324  may be formed of a material with sufficient resiliency such that flexible fibers  324  return to their original orientation following transit of actuator  380 , thereby limiting deflection of catheter  350  within inner volume of introducer  310 . 
     Turning to  FIG.  12 A , shown is a cross-section view of an existing medical device  400 . As can be appreciated, the inner volume of the medical device  400  is tortuous, and the configuration of actuator  480  matches this tortuous geometry, for example arrangement of wall  487 . This arrangement can require a larger volume  418   b  surrounding a catheter (not shown), which can allow for greater deflection of a catheter or other medical implement during displacement thereof. Shown in  FIG.  12 B  is a medical device  500  with a simplified inner geometry of introducer  510 . As can be appreciated by the non-limiting embodiment of  FIG.  12 B , the simplified inner geometry allows for a reduced volume  518   b  as compared to known devices ( 418   b , as shown in  FIG.  12 A ). As also shown in  FIG.  12 B , the simplified geometry allows for a simplified actuator  580 , for example a linear, non-tortuous wall  587  connecting actuator first portion  581  with actuator second portion  585 . While one non-limiting configuration of inner volume  518   b  is shown in  FIG.  12 B , those of skill will appreciate that various cross-sectional shapes can be accommodated, so long as the volume in which a catheter or other medical implement can be deflected is minimized. In non-limiting embodiments, a barrier  524 , for example such as a flexible member described herein, can be included, further limiting the ability of a medical implement, such as a displaceable catheter. 
     In non-limiting embodiments, introducer  510  with a simplified geometry includes a plurality of housing portions, for example as described herein. In non-limiting embodiments, the simplified geometry may require the introducer housing portions to be connected with an ultrasonic weld or adhesive, rather than through a snap or friction fit as is possible with known devices, such as those shown in  FIG.  12 A . 
     With regard to each non-limiting embodiment described herein, one or more additional elements for reducing deflection of a medical implement, such as a displaceable catheter, may be employed. For example, one or more lubricants can be included within introducer interior, on an exterior surface of the medical implement, and/or both. Those of skill in the art will appreciate that any suitable lubricant can be used. In non-limiting embodiments, the lubricant is a silicone-containing lubricant. In non-limiting embodiments or aspects, the lubricant is a polydimethylsiloxane-containing lubricant. In addition, one or more additional supporting structures, for example ribs, protrusions, or the like, may be included within introducer interior. Such structures may be arranged at one or more locations along a longitudinal axis of introducer, limiting the volume within which the medical implement, such as a catheter, can be deflected. In non-limiting embodiments, introducer may be molded with one or more supporting structures. In non-limiting embodiments, one or more supporting structures can be overmolded or attached to introducer through an adhesive, ultrasonic weld, or the like. 
     Although the present disclosure has been described in detail for the purpose of illustration based on what is currently considered to be the most practical and preferred embodiments or aspects, it is to be understood that such detail is solely for that purpose and that the present disclosure is not limited to the disclosed embodiments or aspects, but, on the contrary, is intended to cover modifications and equivalent arrangements that are within the spirit and scope of the appended claims. For example, it is to be understood that the present disclosure contemplates that, to the extent possible, one or more features of any embodiment may be combined with one or more features of any other embodiment.