Patent Publication Number: US-2022233823-A1

Title: Introducer needle with notches for improved flashback

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 16/725,704, filed Dec. 23, 2019, entitled “INTRODUCER NEEDLE WITH NOTCHES FOR IMPROVED FLASHBACK,” which is a continuation-in-part of U.S. patent application Ser. No. 15/946,593, filed Apr. 5, 2018, entitled “INTRODUCER NEEDLE WITH NOTCHES FOR IMPROVED FLASHBACK,” which are hereby incorporated by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Intravenous (IV) catheters are commonly used for a variety of infusion therapies. For example, IV catheters may be used for infusing normal priming fluid, various medicaments, or total parenteral nutrition into a patient. IV catheters may also be used for withdrawing blood from the patient. 
     A common type of IV catheter is an over-the-needle peripheral IV catheter. As its name implies, the over-the-needle peripheral IV catheter may be mounted over an introducer needle having a sharp distal tip. The sharp distal tip may be used to pierce skin and a vasculature of the patient. Insertion of the IV catheter into the vasculature may follow the piercing of the vasculature by the introducer needle. The introducer needle and the IV catheter are generally inserted at a shallow angle through the skin into the vasculature of the patient with a bevel of the introducer needle facing away from the skin of the patient. 
     In order to verify proper placement of the introducer needle and/or the IV catheter in the vasculature, a clinician generally confirms that there is flashback of blood, which may be visible to the clinician. In some instances, the introducer needle may include a single notch, and in response to the distal tip of the introducer needle being positioned within the vasculature, blood may flow proximally through a needle lumen, exit the needle lumen through the notch, and then travel proximally between an outer surface of the introducer needle and an inner surface of another device (e.g., the IV catheter). Accordingly, where the other device is at least partially transparent, the clinician may visualize a small amount of blood “flashback” and thereby confirm placement of the catheter within the vasculature. Presence of a vasculature entrance indicator, such as flashback, may facilitate successful placement of IV catheters. Once placement of the introducer needle within the vasculature has been confirmed, the clinician may temporarily occlude flow in the vasculature and withdraw the introducer needle, leaving the catheter in place for future blood withdrawal and/or fluid infusion. 
     In some markets, priming of the IV catheter is common practice. In order to prime the IV catheter, the clinician may fill the IV catheter with saline or another priming fluid to reduce or eliminate any air pockets disposed within the IV catheter. The saline may also fill a portion of a needle lumen proximate the notch, as well as distal to the notch, all the way to the distal tip of the introducer needle. Thus, when the distal tip of the introducer needle enters the vasculature, flashback may be slowed due to diffusion. Flashback may also be difficult to visualize due to mixing of flashback with the saline. 
     Furthermore, many integrated IV catheter systems having an integrated extension tube do not include a flash chamber, which may be vented. Examples of integrated IV catheter systems may include, for example, the BD NEXIVA™ Closed IV Catheter System, the BD NEXIVA™ DIFFUSICS™ Closed IV Catheter System, or the Becton Dickinson PEGASUS™ Safety Closed IV Catheter System. Thus, after the priming of the IV catheter, the IV catheter system may no longer be vented, and when the distal tip of the introducer needle enters the vasculature, blood may only slowly diffuse into the introducer needle. Also, transfixing of the vasculature may not be observed since the proximal diffusion of the blood may continue even when the distal tip is no longer properly placed within the vasculature. 
     Moreover, sometimes the clinician may not prime the integrated IV catheter system and may instead wait for flashback to flow through the integrated IV catheter system to purge any air from the integrated IV catheter system. For example, the clinician may wait for blood within the integrated IV catheter system to flow proximally through the introducer needle, out the notch, and through the IV catheter, a catheter adapter, and the integrated extension tube to a luer adapter, where air may exit the integrated IV catheter system. Such a process may be time consuming. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed. 
     BRIEF SUMMARY OF THE INVENTION 
     The present disclosure relates generally to an introducer needle having a first notch and a second notch, and related devices, systems, and methods. In some embodiments, the introducer needle may include a proximal end, a distal tip, and a needle lumen extending between the proximal end and the distal tip. In some embodiments, the introducer needle may include a wall, which may define the needle lumen. In some embodiments, the first notch may be formed through the wall, and the second notch may be formed through the wall. In some embodiments, the second notch may be proximal to the first notch. 
     In some embodiments, a catheter system may include a catheter adapter, which may include a distal end, a proximal end, and a lumen extending between the distal end and the proximal end. In some embodiments, the catheter system may include a catheter, which may include an IV catheter, such as a peripheral IV catheter, for example. In some embodiments, the catheter may extend distally from the distal end of the catheter adapter. In some embodiments, the catheter system may include the introducer needle, which may extend through the catheter and beyond the distal end of the catheter when the introducer needle is in an insertion position for insertion into vasculature of a patient. 
     In some embodiments, the first notch of the introducer needle may be disposed within the catheter when the introducer needle is in the insertion position. In some embodiments, at least a portion of the catheter may be transparent or translucent. In some embodiments, where the proximal end of the introducer needle is vented such that air and/or fluid may travel proximally through the introducer needle, presence of the first and second notches may facilitate pressure-driven blood flow into the catheter for improved flashback and detection of transfixing. In some embodiments, the first and second notches may improve first needle stick success by improving the quality of flashback. 
     In further detail, in some embodiments, the catheter system may include a first fluid pathway, which may extend from the first notch to the second notch between an outer surface of the introducer needle and an inner surface of a wall of the catheter, and a second fluid pathway, which may extend from the first notch to the second notch within the needle lumen. During flashback, blood may flow through the first fluid pathway and/or the second fluid pathway. In some embodiments, the first fluid pathway may provide pressure-driven flashback, even after the catheter system is primed. In some embodiments, flashback may be faster through the first fluid pathway than the second fluid pathway. In some embodiments, flashback through the first fluid pathway may be visible due to the transparency of the catheter. 
     In some embodiments, the first fluid pathway may have a larger volume than the second fluid pathway, which may facilitate faster flashback through the first fluid pathway than the second fluid pathway. In some embodiments, a cross-section taken through the catheter system perpendicular to a central axis of the catheter system and between the first notch and the second notch may include a needle lumen area and another area between the outer surface of the introducer needle and the inner surface of the wall of the catheter. In some embodiments, the other area may be greater than the needle lumen area. In some embodiments, the other area may be greater than the needle lumen area in each cross-section taken through the catheter system perpendicular to the central axis along an entire length between the first notch and the second notch. 
     In some embodiments, the catheter system may include a flash chamber, which may facilitate flashback. In some embodiments, the flash chamber may be in fluid communication with the needle lumen. In some embodiments, the flash chamber may include a gas permeable vent. In some embodiments, the gas permeable vent of the flash chamber may provide the venting that allows air and/or fluid to travel proximally through the introducer needle. In some embodiments, the flash chamber may be disposed proximal to the proximal end of the introducer needle. In some embodiments, the gas permeable vent may provide at least some resistance to air flow. 
     In some embodiments, the catheter may be primed prior to insertion of the catheter and introducer needle into the vasculature of the patient. In some embodiments, the catheter may be primed when the introducer needle is in the insertion position. In some embodiments, in order to prime the catheter, the clinician may fill the catheter with a priming fluid, such as, for example, saline, to reduce or eliminate any air pockets disposed within the catheter. In some embodiments, the priming fluid may be disposed in a first portion of a needle lumen proximate the first notch and including the distal tip of the introducer needle. Additionally, in some embodiments, the priming fluid may be disposed in a second portion of the needle lumen proximate the second notch. In some embodiments, when the gas permeable vent provides the resistance, the priming fluid in the first portion may be separated from the priming fluid in the second portion, and air may be disposed between the first portion and the second portion in the needle lumen. 
     In some embodiments, in response to the distal tip of the introducer needle entering the vasculature, blood pressure will drive the flashback into the needle. Additionally, in some embodiments, at least some of the flashback may then be driven out of the introducer needle at the first notch and into the catheter. Furthermore, in some embodiments, in response to the distal tip of the introducer needle entering the vasculature, the priming fluid outside the introducer needle and within the catheter tube between the first notch and the second notch may be driven into the introducer needle through the second notch and may eventually reach the flash chamber. In some embodiments, in response to the distal tip of the introducer needle entering the vasculature, blood may flow proximally through the needle as well. In some embodiments, the pressure-driven blood flow through the first fluid pathway, which may initially be filled with the priming fluid, may be faster than diffusion. 
     In some embodiments, the flash chamber may include a large, non-restrictive volume, which may facilitate the pressure-driven flow of the priming fluid and/or blood towards or into the flash chamber. In some embodiments, a volume of the flash chamber may be large enough to hold the priming fluid disposed outside the introducer needle and within the catheter between the first notch and the second notch and/or the priming fluid that may travel into the flash chamber during priming of the catheter. Additionally, in some embodiments, the volume of the flash chamber may be large enough to hold blood when the distal tip of the introducer needle is disposed within the vasculature. 
     In some embodiments, a portion of the wall of the introducer needle between the first notch and the second notch may be pinched or crimped such that fluid, such as blood, is prevented from flowing in the needle lumen between the first notch and the second notch. In some embodiments, the crimped portion of the wall may facilitate rapid flashback through the first fluid pathway. 
     In some embodiments, the second notch may be disposed within the catheter when the needle is in the insertion position. In some embodiments, the second notch may be disposed within the lumen of the catheter adapter when the needle is in the insertion position. In some embodiments, a distance between the first notch and the second notch may be greater than a length of the catheter, which may facilitate visibility of transfixing. 
     In some embodiments, the catheter system may include a needle hub, which may be coupled to the catheter adapter when the introducer needle is in the insertion position. In some embodiments, a proximal end of the introducer needle may be secured within the needle hub. In some embodiments, the flash chamber may be disposed within the needle hub. 
     In some embodiments, the catheter system may include a blood control septum, which may be disposed within the lumen of the catheter adapter. In some embodiments, the septum may divide the lumen of the catheter adapter into a proximal chamber and a distal chamber. In some embodiments, the second notch may be disposed distal to the septum when the introducer needle is in the insertion position. 
     In some embodiments, the catheter adapter may include a gas permeable vent, which may be selectively opened and/or closed. In some embodiments, the gas permeable vent of the catheter adapter may be disposed distal to the septum such that air in the distal chamber may freely flow out of the gas permeable vent when the vent is opened. In some embodiments, the gas permeable vent of the catheter adapter may be opened during priming of the catheter, which may prevent the priming fluid from being disposed in the first portion of the needle proximate the first notch and/or the second portion of the needle proximate the second notch, as the gas permeable vent of the catheter adapter may provide a path of low resistance for the priming fluid. 
     In some embodiments, the catheter system may include a seal, which may be secured within the lumen of the catheter adapter. In these and other embodiments, the portion of the wall of the introducer needle between the first notch and the second notch may be pinched or crimped such that fluid is prevented from flowing in the needle lumen between the first notch and the second notch. In some embodiments, the introducer needle may be rotatable from a priming position to the insertion position and/or from the insertion position to the priming position. In some embodiments, the introducer needle may be disposed in the priming position during priming of the catheter and may be disposed in the insertion position during insertion into the vasculature. 
     In some embodiments, when the introducer needle is in the priming position, the seal may cover and seal the second notch, which may prevent fluid from flowing through the second notch. In some embodiments, when the introducer needle is in the insertion position, the seal may not cover or seal the second notch and fluid may flow through the second notch. In some embodiments, in response to the second notch being uncovered or unsealed, rapid flashback may occur with blood flowing into the needle lumen via the second notch. In some embodiments, the seal may include a septum or flapper. 
     In some embodiments, the introducer needle may be rotatable between the priming position and the insertion position about the central axis of the catheter system, which may extend through the needle lumen. In some embodiments, the introducer needle may be rotated by twisting the needle hub. In some embodiments, the introducer needle may be rotated in a first direction and/or a second direction opposite the first direction. In some embodiments, the second notch may be aligned with the seal when the introducer needle is in the priming position and the insertion position. In these and other embodiments, the introducer needle may extend a same distance from the distal tip of the catheter when the introducer needle is in the priming position as when the introducer needle is in the insertion position. 
     In some embodiments, the catheter system may include a plug constructed of a dissolvable material. In some embodiments, the plug may be disposed on top of the second notch to seal the second notch during priming of the catheter system. 
     In some embodiments, the catheter adapter of the catheter system may include the distal end, the proximal end, the lumen extending between the distal end and the proximal end, and a side port. In some embodiments, the side port may be disposed between the distal end of the catheter adapter and the proximal end of the catheter adapter and may be in fluid communication with the lumen of the catheter adapter. In some embodiments, an extension tube may be integrated within the side port. In some embodiments, the catheter may extend distally from the distal end of the catheter adapter. 
     In some embodiments, the introducer needle may include the wall defining the needle lumen, the first notch formed through the wall, and the second notch formed through the wall. In some embodiments, the second notch may be proximal to the first notch. In some embodiments, the introducer needle may extend through the catheter and beyond the distal end of the catheter when the introducer needle is in the insertion position for insertion into the patient. 
     In some embodiments, the catheter system may include a seal element. In some embodiments, the seal element may block a fluid pathway that extends from the extension tube through the catheter. In some embodiments, the seal element may be disposed proximal to the second notch and distal to the side port. In some embodiments, the seal element may prevent the priming fluid from travelling distal to the seal element between the outer surface of the introducer needle and the inner surface of the catheter. In some embodiments, the seal element may be disposed within the catheter between the outer surface of the introducer needle and an inner surface of the catheter. In some embodiments, the seal element may be disposed within the catheter adapter between the outer surface of the introducer needle and an inner surface of the catheter adapter. 
     In some embodiments, a portion of an outer surface of the introducer needle may include a groove. In some embodiments, the portion of the outer surface of the introducer needle may be disposed within the septum. In some embodiments, the groove may be configured to allow air to pass through the septum. 
     In some embodiments, the needle hub may include the flash chamber, which may be in fluid communication with the needle lumen. In some embodiments, the needle hub may include a gas permeable vent proximate the flash chamber. In some embodiments, the catheter adapter may include a gas permeable vent proximal to the septum. 
     In some embodiments, the needle hub may include another extension tube. In some embodiments, a distal end of the other extension tube may be in fluid communication with the flash chamber. In some embodiments, a proximal end of the other extension tube may be coupled to a holder configured to receive an evacuated blood collection tube. In some embodiments, the catheter system may include a needle safety, which may be disposed between the needle hub and the catheter adapter. 
     In some embodiments, a method may include coupling a device containing priming fluid to an adapter of the catheter system. In some embodiments, the adapter may include a Y-adapter or another suitable adapter. In some embodiments, the adapter may be coupled to the proximal end of the extension tube. In some embodiments, the method may include priming the catheter system with by activating the device containing priming fluid such that the priming fluid flows distally through the catheter system to the seal element and stops at the seal element. In some embodiments, after priming the catheter system with the device containing priming fluid such that the priming fluid flows distally through the catheter system to the seal element and stops at the seal element, the method may include inserting the catheter into vasculature. 
     In some embodiments, in response to inserting the catheter into the vasculature, blood may flow proximally into the needle lumen, then out of the needle lumen through the first notch into a space between an outer surface of the introducer needle and an inner surface of the catheter, and then into the needle lumen through the second notch. In some embodiments, after the blood flows into the needle lumen through the second notch, the blood may flow into the flash chamber and/or through the other extension tube. In some embodiments, after inserting the catheter into the vasculature, blood may be collected using the catheter system. 
     In some embodiments, after inserting the catheter into the vasculature and/or collecting blood, the method may include withdrawing the introducer needle in a proximal direction. In some embodiments, in response to withdrawing the introducer needle in the proximal direction, a seal formed by the seal element may be broken such that the priming fluid joins the blood disposed within the catheter distal to the seal. In some embodiments, in response to the seal being broken, the catheter may remain in place within the vasculature for use in future infusions and/or blood draw. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed. It should be understood that the various embodiments are not limited to the arrangements and instrumentality shown in the drawings. It should also be understood that the embodiments may be combined, or that other embodiments may be utilized and that structural changes, unless so claimed, may be made without departing from the scope of the various embodiments of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       Example embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
         FIG. 1  is a top view of an example catheter system, illustrating the catheter system in an insertion position, according to some embodiments; 
         FIG. 2A  is a cross-sectional view of an example introducer needle disposed within a an example catheter, illustrating the introducer needle in the insertion position, according to some embodiments; 
         FIG. 2B  is a cross-sectional view along line  2 B- 2 B of  FIG. 2A , according to some embodiments; 
         FIG. 2C  is a cross-sectional view of the introducer needle of  FIG. 2A  having an example crimp feature and disposed within the catheter, illustrating the introducer needle in the insertion position, according to some embodiments; 
         FIG. 2D  is a cross-sectional view of the introducer needle of  FIG. 2A  disposed within the catheter, illustrating the introducer needle in the insertion position and an example plug constructed of a dissolvable material, according to some embodiments; 
         FIG. 2E  is a partial cutaway of the introducer needle of  FIG. 2A  disposed within the catheter, illustrating the introducer needle in the insertion position and a sleeve element constructed of a dissolvable material, according to some embodiments; 
         FIG. 3A  is a top view of an example needle assembly, according to some embodiments; 
         FIG. 3B  is a partial cutaway view of the needle assembly of  FIG. 3A , according to some embodiments; 
         FIG. 4A  is a cross-sectional view of the catheter system of  FIG. 1A , illustrating the catheter system in the insertion position and an example seal covering an example second notch, according to some embodiments; 
         FIG. 4B  is a cross-sectional view of the catheter system of  FIG. 1A , illustrating the seal removed from the second notch, according to some embodiments; 
         FIG. 5A  is a cross-sectional view of another catheter system, according to some embodiments; 
         FIG. 5B  is an enlarged cross-sectional view of a distal end of the catheter system of  FIG. 5A , according to some embodiments; 
         FIG. 5C  is an enlarged cross-sectional view of a portion of the catheter system of  FIG. 5A , according to some embodiments; 
         FIG. 5D  is a transverse cross-sectional view at an example seal of the catheter system of  FIG. 5A , according to some embodiments; 
         FIG. 5E  is a cross-sectional view of the catheter system of  FIG. 5A , illustrating an example needle assembly removed from the catheter system, according to some embodiments; 
         FIG. 5F  is an enlarged cross-sectional view of a portion of the catheter system of  FIG. 5A , illustrating an example seal element in another location, according to some embodiments; and 
         FIG. 5G  is a cross-sectional view of the catheter system of  FIG. 5A , illustrating another example needle hub, according to some embodiments. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present disclosure relates generally to an introducer needle having a first notch and a second notch, and related devices, systems, and methods. Referring now to  FIG. 1 , in some embodiments, a catheter system  10  may include a catheter adapter  12 , which may include a distal end, a proximal end, and a lumen extending between the distal end and the proximal end. In some embodiments, the catheter system  10  may include a catheter  14 , which may include an IV catheter, such as a peripheral IV catheter, for example. In some embodiments, the catheter  14  may extend distally from the distal end of the catheter adapter  12 . In some embodiments, the catheter system  10  may include the introducer needle  16 , which may extend through the catheter  14  and beyond the distal end of the catheter  14  when the introducer needle  16  is in an insertion position for insertion into vasculature of a patient. 
     In some embodiments, the catheter system  10  may include a needle hub  18 , which may be coupled to the catheter adapter  12  when the introducer needle  16  is in the insertion position. In some embodiments, a proximal end of the introducer needle  16  may be secured within the needle hub  18 . In some embodiments, the catheter system  10  may include a needle shield  19 . In some embodiments, the catheter system  10  may be integrated or non-integrated. In some embodiments, the catheter system  10  may include the needle shield  19  or any other type of suitable needle safety mechanism. 
     Referring now to  FIG. 2A , in some embodiments, the introducer needle  16  may include a proximal end, a distal tip  20 , and a needle lumen  22  extending between the proximal end and the distal tip  20 . In some embodiments, the introducer needle  16  may include a wall  24 , which may define the needle lumen  22 . In some embodiments, the first notch  26  may be formed through the wall  24 , and the second notch  28  may be formed through the wall  24 . In some embodiments, the second notch  28  may be proximal to the first notch  26 . In some embodiments, the wall  24  may include more than two notches. 
     In some embodiments, the first notch  26  of the introducer needle  16  may be disposed within the catheter  14  when the introducer needle  16  is in the insertion position. In some embodiments, at least a portion of the catheter  14  may be transparent or translucent. In some embodiments, presence of the second notch  28  may facilitate pressure-driven blood flow into the catheter  14  for improved flashback and detection of transfixing. In some embodiments, the second notch  28  may improve first needle stick success by improving the quality of flashback. 
     In further detail, in some embodiments, the catheter system  10  may include a first fluid pathway  30 , which may extend from the first notch  26  to the second notch  28  between an outer surface of the introducer needle  16  and an inner surface of a wall  32  forming the catheter  14 , and a second fluid pathway  34 , which may extend from the first notch  26  to the second notch  28  within the needle lumen  22 . In some embodiments, during flashback, blood may flow through the first fluid pathway  30  and/or the second fluid pathway  34 . In some embodiments, the first fluid pathway  30  may provide pressure-driven flashback, even after the catheter system  10  is primed. In some embodiments, flashback or proximal blood travel may be faster through the first fluid pathway  30  than the second fluid pathway  34 . In some embodiments, flashback through the first fluid pathway  30  may be visible due to the transparency or translucency of the catheter  14 . 
     In some embodiments, the second notch  28  may be disposed within the catheter  14  when the introducer needle  16  is in the insertion position. In some embodiments, the second notch  28  may be disposed within the lumen of the catheter adapter (as illustrated, for example, in  FIGS. 4A-4B ) when the introducer needle  16  is in the insertion position. In some embodiments, a distance between the first notch  26  and the second notch  28  may be greater than a length of the catheter  14 , which may facilitate visibility of transfixing. 
     In some embodiments, the first fluid pathway  30  may have a larger volume than the second fluid pathway  34 , which may facilitate faster flashback or proximal blood travel through the first fluid pathway  30  than the second fluid pathway  34 . Referring now to  FIG. 2B , in some embodiments, a cross-section taken through the catheter system  10  perpendicular to a central axis  40  of the catheter system  10  and between the first notch  26  and the second notch  28  may include a needle lumen area  36  and another area  38  between the outer surface of the introducer needle  16  and the inner surface of the wall  32  of the catheter  14 . In some embodiments, the other area  38  may be greater than the needle lumen area  36 . In some embodiments, the other area  38  may be greater than the needle lumen area  36  in each cross-section taken through the catheter system  10  perpendicular to the central axis  40  along an entire length between the first notch  26  and the second notch  28 . 
     Referring now to  FIG. 2C , in some embodiments, a portion of the wall  24  of the introducer needle  16  between the first notch  26  and the second notch  28  may be pinched or crimped such that fluid, such as blood, is prevented from flowing in the needle lumen  22  between the first notch  26  and the second notch  38 . In some embodiments, the crimped portion  42  of the wall  24  may facilitate rapid flashback through the first fluid pathway  30 . 
     Referring now to  FIG. 2D , in some embodiments, a plug  42 , which may be constructed of a dissolvable material, may seal the second notch  28  during priming of the catheter  14 . In some embodiments, the plug  42  may be dissolved when the catheter system  10  is introduced into the vasculature of the patient. 
     Referring now to  FIG. 2E , in some embodiments, a sleeve  44 , which may be constructed of a dissolvable material, may seal the second notch  28  during priming of the catheter  14 . In some embodiments, the sleeve  44  may be dissolved when the catheter system  10  is introduced into the vasculature of the patient. 
     Referring now to  FIGS. 3A-3B , in some embodiments, the catheter system  10  may include a flash chamber  46 , which may facilitate flashback. In some embodiments, the flash chamber  46  may be in fluid communication with the needle lumen  22 . In some embodiments, the flash chamber  46  may include a gas permeable vent  48 . In some embodiments, the flash chamber  46  may be disposed proximal to the proximal end  49  of the introducer needle  16 . In some embodiments, the gas permeable vent  48  may provide at least some resistance to air flow. In some embodiments, the flash chamber  46  may be disposed within the needle hub  18 , as illustrated, for example, in  FIG. 3B .  FIGS. 3A-3B  illustrate a needle assembly with the needle shield  19  removed, according to some embodiments. 
     In some embodiments, the catheter  14  may be primed prior to insertion of the catheter  14  and the introducer needle  16  into the vasculature of the patient. In some embodiments, the catheter  14  may be primed when the introducer needle  16  is in the insertion position. In some embodiments, in order to prime the catheter  14 , the clinician may fill the catheter  14  with a priming fluid, such as, for example, saline, to reduce or eliminate any air pockets disposed within the catheter. In some embodiments, the priming fluid may be disposed in a first portion of a needle lumen proximate the first notch  26  and including the distal tip  20  of the introducer needle  16 . Additionally, in some embodiments, the priming fluid may be disposed in a second portion of the needle lumen  22  proximate the second notch  28 . In some embodiments, when the gas permeable vent  48  provides the resistance, the priming fluid in the first portion may be separated from the priming fluid in the second portion, and air may be disposed between the first portion and the second portion in the needle lumen  22 . 
     In some embodiments, in response to the distal tip  20  of the introducer needle  16  entering the vasculature, blood pressure will drive the flashback into the introducer needle  16 . Additionally, in some embodiments, at least some of the flashback may then be driven out of the introducer needle  16  at the first notch  26  and into the catheter  14 . Furthermore, in some embodiments, in response to the distal tip  20  of the introducer needle  16  entering the vasculature, the priming fluid outside the introducer needle  16  and within the catheter  14  between the first notch  26  and the second notch  28  may be driven into the introducer needle  16  through the second notch  28  and may eventually reach the flash chamber  46 . In some embodiments, in response to the distal tip  20  of the introducer needle  16  entering the vasculature, blood may flow proximally through the introducer needle  16  as well. In some embodiments, the pressure-driven blood flow through the first fluid pathway  30 , which may initially be filled with the priming fluid, may be faster than diffusion. 
     In some embodiments, the flash chamber  46  may include a large, non-restrictive volume, which may facilitate the pressure-driven flow of the priming fluid and/or blood towards or into the flash chamber  46 . In some embodiments, a volume of the flash chamber  46  may be large enough to hold the priming fluid disposed outside the introducer needle  16  and within the catheter  14  between the first notch  26  and the second notch  28  and/or the priming fluid that may travel into the flash chamber  46  during priming of the catheter  14 . Additionally, in some embodiments, the volume of the flash chamber  46  may be large enough to hold blood when the distal tip  20  of the introducer needle  16  is disposed within the vasculature. 
     Referring now to  FIGS. 4A-4B , in some embodiments, the catheter system  10  may include a blood control septum  50 , which may be disposed within the lumen  52  of the catheter adapter  12 . In some embodiments, the septum  50  may divide the lumen  52  of the catheter adapter  12  into a proximal chamber  54  and a distal chamber  56 . In some embodiments, the second notch  28  may be disposed distal to the septum  50  when the introducer needle  16  is in the insertion position. 
     In some embodiments, the catheter adapter  12  may include a gas permeable vent  57 , which may be selectively opened and/or closed. In some embodiments, the gas permeable vent  57 , which may be disposed through a wall of the catheter adapter  12 , may be disposed distal to the septum  50  such that air in the distal chamber  56  may freely flow out of the gas permeable vent  57  when the gas permeable vent  57  is opened. In some embodiments, the gas permeable vent  57  of the catheter adapter  12  may be opened during priming of the catheter  14 , which may prevent the priming fluid from being disposed in the first portion of the introducer needle  16  proximate the first notch  26  and/or the second portion  28  of the introducer needle  16  proximate the second notch  28 . 
     In some embodiments, the catheter system  10  may include a seal  58 , which may be secured within the lumen  52  of the catheter adapter  12 . In these and other embodiments, the portion of the wall of the introducer needle  16  between the first notch  26  and the second notch  28  may be pinched or crimped such that fluid is prevented from flowing in the needle lumen  22  between the first notch  26  and the second notch  28 . In some embodiments, the introducer needle  22  may be rotatable from a priming position to the insertion position and/or from the insertion position to the priming position.  FIG. 4A  illustrates the introducer needle  22  in the insertion position, according to some embodiments, and  FIG. 4B  illustrates the introducer needle  22  in the priming position, according to some embodiments. In some embodiments, the introducer needle  16  may be disposed in the priming position during priming of the catheter and may be disposed in the insertion position during insertion into the vasculature. In some embodiments, the catheter system  10  may not include the seal  58  and/or the priming and insertions positions may be the same. 
     In some embodiments, when the introducer needle  16  is in the priming position, the seal  58  may cover or seal the second notch, which may prevent fluid from flowing through the second notch  28 . In some embodiments, when the introducer needle  16  is in the insertion position, the seal  58  may not cover or seal the second notch  28  and fluid may flow through the second notch  28 . In some embodiments, in response to the second notch  28  being uncovered or unsealed, rapid flashback may occur with blood flowing into the needle lumen  22  via the second notch  28 . In some embodiments, the seal  58  may include a septum or flapper. 
     In some embodiments, the introducer needle  16  may be rotatable between the priming position and the insertion position about the central axis  40  of the catheter system  10 , which may extend through the needle lumen  22 . In some embodiments, the introducer needle  16  may be rotated by twisting the needle hub  18 . In some embodiments, the introducer needle  16  may be rotated in a first direction and/or a second direction opposite the first direction. In some embodiments, the second notch  28  may be aligned with the seal when the introducer needle is in the priming position and the insertion position, as illustrated in  FIGS. 4A-4B , for example. In these and other embodiments, the introducer needle  16  may extend a same distance from the distal tip of the catheter  14  when the introducer needle  16  is in the priming position as when the introducer needle  16  is in the insertion position. 
     Referring now to  FIGS. 5A-5F , a catheter system  60  is illustrated, according to some embodiments. In some embodiments, the catheter system  60  may be similar or identical to the catheter system  10  discussed with respect to  FIGS. 1-4A  in terms of one or more included features and/or operation. In some embodiments, the catheter system  60  may facilitate priming of the catheter system  60  and reduction of air within the catheter system  60  prior to insertion into the vasculature of the patient. In these embodiments, the catheter system  60  may also allow the clinician to see both primary flashback within the catheter  14  and secondary flashback within the flash chamber  46  with blood that is not diluted with priming fluid. In some embodiments, the catheter system  60  facilitates priming of a portion of the catheter system  60  prior to insertion of the catheter system  60  into the vasculature of the patient while still allowing efficient blood flashback for vein confirmation. 
     In some embodiments, the catheter system  60  may include the catheter adapter  12 , which may include a distal end  62 , a proximal end  64 , the lumen  52  extending between the distal end  62  and the proximal end  64 , and a side port  68 . In some embodiments, the side port  68  may be disposed between the distal end  62  of the catheter adapter  12  and the proximal end  64  of the catheter adapter  12  and may be in fluid communication with the lumen  52  of the catheter adapter  12 . In some embodiments, an extension tube  70  may be integrated within the side port  68 . 
     In some embodiments, the catheter  14  may extend distally from the distal end  62  of the catheter adapter  12 . In some embodiments, the catheter  14  may include a peripheral IV catheter, a midline IV catheter, or a peripherally inserted central catheter. In some embodiments, the introducer needle  16  may include the wall  24  defining the needle lumen  22 , the first notch  26  formed through the wall  24 , and the second notch  28  formed through the wall  24 . In some embodiments, the second notch  28  may be proximal to the first notch  26 . In some embodiments, the introducer needle  16  may extend through the catheter  14  and beyond the distal end of the catheter  14  when the introducer needle  16  is in the insertion position for insertion into the patient. In some embodiments, the first notch  26  and/or the second notch  28  may be disposed within the catheter  14  when the introducer needle  16  is in the insertion position. 
     In some embodiments, the introducer needle  16  may include a block  71  disposed between the first notch  26  and the second notch  28 . For example, a portion of the wall of the introducer needle between the first notch  26  and the second notch  28  may be pinched or crimped such that fluid, such as blood, may be prevented from flowing in the needle lumen  22  between the first notch  26  and the second notch  28 . In some embodiments, the block  71  may facilitate rapid flashback through the first fluid pathway  30  (see, for example,  FIG. 2C ). 
     In some embodiments, the catheter system  60  may include a seal element  72 . In some embodiments, the seal element  72  may block a fluid pathway that extends through the extension tube  70  through the catheter  14 . In some embodiments, the seal element  72  may be disposed proximal to the second notch  28  and distal to the side port  68  or a junction between the side port  68  and the lumen  52 . In some embodiments, the seal element  72  may prevent the priming fluid from travelling distal to the seal element  72  between the outer surface of the introducer needle  16  and the inner surface of the catheter  14 . 
     In some embodiments, the seal element  72  may be disposed within the catheter  14  between the outer surface of the introducer needle  16  and an inner surface of the catheter  14 , as illustrated, for example, in  FIG. 5A . In some embodiments, the seal element  72  may be disposed proximal to the catheter  14  and within the lumen  52  distal to the junction with the side port  68  and the lumen  52 , as illustrated, for example, in  FIG. 5F . In some embodiments, the seal element  72  may extend through the proximal end of the catheter  14  and contact the inner surface of the catheter adapter  12  and/or a wedge  73  that secures the catheter  14  within the catheter adapter  12 . 
     In some embodiments, the seal element  72  may prevent fluid, such as priming fluid, from travelling distal to the seal element  72  within the catheter adapter  12  and/or distal to the seal element  72  between the outer surface of the introducer needle  16  and the inner surface of the catheter  14 . In some embodiments, the seal element  72  may be proximal to the second notch  28 . In some embodiments, the seal element  72  may prevent the fluid from travelling distal to the seal element  72  when the introducer needle  16  extends through the seal element  72 . 
     In some embodiments, the seal element  72  may be a separate element from the catheter adapter  12 , catheter  14 , the wedge  73 , or another portion of the catheter system  60 . In these embodiments, the seal element  72  may be coupled or positioned within the catheter system  60 . In some embodiments, the seal element  72  may be engaged in an interference fit with one or more of the following: the inner surface of the catheter adapter  12 , the catheter  14 , or the wedge  73 . In some embodiments, the seal element  72  may be constructed of metal, plastic, silicon, or any other material configured to form a seal around the introducer needle  16 . 
     In some embodiments, the seal element  72  may be integrally formed or monolithically formed as a single unit with the catheter  14 , the catheter adapter  12 , or the wedge  73 . In some embodiments, the seal element  72  may include a necked down or narrowed inner diameter portion of the catheter  14 . In some embodiments, the seal element  72  may be annular and may surround the introducer needle  16 . In some embodiments, an outer perimeter or outer circumference of the seal element  72  may contact the inner surface of one or more of the following: the catheter adapter  12 , the catheter  14 , and the wedge  73 . In some embodiments, an inner perimeter or inner circumference of the seal element  72  may contact the outer surface of the introducer needle  16  to prevent fluid from travelling through the catheter  14 . In some embodiments, the seal element  72  may include a hole extending through the seal element  72 , which may include the inner perimeter or the inner circumference. 
     In some embodiments, the seal element  72  may not be attached to the introducer needle  16 , the catheter  14 , the catheter adapter  12 , or the wedge  73 . In some embodiments, an outer perimeter or outer circumference of the seal element  72  may be attached to the inner surface of the catheter  14 . In some embodiments, the inner perimeter or inner circumference of the seal element  72  may be attached to the outer surface of the introducer needle  16  to prevent fluid from travelling through the catheter  14 . In some embodiments, the seal element  72  may be constructed of a tear-able material configured to tear in response to proximal withdrawal of the introducer needle  16  with respect to the catheter adapter  12  and the catheter  14 . 
     In some embodiments, a portion of an outer surface of the introducer needle  16  may include a groove  74 . In some embodiments, the introducer needle  16  may be partially crimped to form the groove  74  such that fluid may still flow through the needle lumen  22 . In some embodiments, the portion of the outer surface of the introducer needle  16  may be disposed within the septum  50 . In some embodiments, the groove  74  may be configured to allow air to pass through the septum  50 . 
     In some embodiments, the needle hub  18  may include the flash chamber  46 , which may be in fluid communication with the needle lumen  22  via an opening in the proximal end of the introducer needle  16 . In some embodiments, the needle hub  18  may include the gas permeable vent  48 , which may be proximate the flash chamber  46 . 
     In some embodiments, the catheter adapter  12  may include a gas permeable vent  76 , which may be proximal to the septum  50 . In some embodiments, the gas permeable vent  76  and/or the gas permeable vent  48  may include paper, fiber, membrane, or another material with a porosity that allow air to escape while limiting fluid from escaping. In some embodiments, the gas permeable vent  76  may be permeable to air but not blood. In some embodiments, a location of the gas permeable vent  76  may vary. In some embodiments, the gas permeable vent  76  may facilitate exit from the catheter system  60  of air travelling proximally through the groove  74 . In some embodiments, the gas permeable vent  76  may be disposed within the needle shield  19 , which may be disposed between the needle hub  18  and the catheter adapter  12 . In some embodiments, the needle shield  19  may include any active or passive needle safety device configured to shield a sharp distal tip of the introducer needle in response to withdrawal of the introducer needle  16 . 
     In some embodiments, a device containing priming fluid may be coupled to an adapter  78  of the catheter system  60 . In some embodiments, the priming fluid may include saline. In some embodiments, the device may include a syringe or any other suitable device that may be coupled to the catheter system  60 . In some embodiments, the device may be directly coupled to the adapter  78  or coupled to the adapter  78  via another connector. 
     In some embodiments, the adapter  78  may be coupled to the proximal end of the extension tube  70 . In some embodiments, the catheter system  60  may be primed, using the device containing priming fluid, such that the priming fluid flows distally through the catheter system  60  to the seal element  72  and stops at the seal element  72 . In some embodiments, the priming fluid may not flow distal to the seal element  72 . In some embodiments, the catheter  14  distal to the seal element  72  may be dry and the needle lumen  22  may remain dry, while the adapter  78 , the extension tube  70 , the side port  68 , and a portion of the lumen  52  between the seal element  72  and the septum  50  may all be primed such that any air bubbles are removed from a fluid pathway extending from the catheter adapter  12  to the adapter  78 . In some embodiments, the septum  50  may prevent priming fluid from passing through the septum  50  to the proximal end  64  of the catheter adapter  12 . 
     In some embodiments, after priming the catheter system  60  with the device containing priming fluid such that the priming fluid flows distally through the catheter system  60  to the seal element  72  and stops at the seal element  72 , a clinician may insert the catheter  14  into vasculature of a patient. In some embodiments, in response to inserting the catheter  14  into the vasculature, blood may flow proximally into the needle lumen  22  at the distal tip  20 , then out of the needle lumen  22  through the first notch  26  into a space between an outer surface of the introducer needle  16  and an inner surface of the catheter  14 , and then into the needle lumen  22  through the second notch  28 . In some embodiments, after the blood flows into the needle lumen  22  through the second notch  28 , the blood may flow into the flash chamber  46 . 
     In some embodiments, in response to observation of blood flashback by the clinician or completion of blood collection, the clinician may withdraw the introducer needle  16  in a proximal direction. In some embodiments, in response to withdrawing the introducer needle in the proximal direction, a seal formed by the seal element  72  around the introducer needle  16  may be broken such that the priming fluid joins the blood, which may be disposed in the space between the outer surface of the introducer needle  16  and the inner surface of the catheter  14  distal to the seal element  72 . Thus, in some embodiments, the fluid pathway extending from the catheter adapter  12  to the adapter  78  may merge with a fluid pathway extending from the distal tip  20  into the needle lumen  22  and into the space between an outer surface of the introducer needle  16  and the inner surface of the catheter  14 . 
     In some embodiments, in response to the seal being broken, the catheter  14  may remain in place within the vasculature for use in future infusions and/or blood collection. In some embodiments, the seal may be broken when the introducer needle  16  is withdrawn in the proximal direction such that the introducer needle  16  is removed from the seal element  72  and no longer extends through the seal element  72 . In these and other embodiments, fluid may flow through the hole or middle of the seal element  72 . 
     Referring now to  FIG. 5G , in some embodiments, the needle hub  18  may include another extension tube  80 . In some embodiments, a distal end  82  of the other extension tube  80  may be in fluid communication with the flash chamber  46 . In some embodiments, a proximal end  83  of the other extension tube  80  may be coupled to a holder  84  configured to receive an evacuated blood collection tube. In some embodiments, the clinician may use the catheter system  60  to collect or sample blood prior to fully removing the introducer needle  16  from the catheter adapter  12  and while the catheter  14  is inserted within the vasculature of the patient. 
     In some embodiments, the holder  84  may include a body  86 , which may include a distal end  88 , a proximal end  90 , and a lumen  92  extending through the distal end  88  of the body  86  and the proximal end  90  of the body  86 . In some embodiments, the distal end  88  of the body  86  may include a male port or a female port. In some embodiments, the holder  84  may include a needle  94  extending from the proximal end  90  of the body  86  and configured to receive the evacuated blood collection tube. 
     In some embodiments, the holder  84  may include an elastomeric sheath  96 , which may be coupled to the body  86 . In some embodiments, a proximal end of the needle  94  may be enveloped within the elastomeric sheath  96 . In some embodiments, the elastomeric sheath  96  may include an open distal end and a closed proximal end. In some embodiments, in response to the evacuated blood collection tube pushing the elastomeric sheath  96  distally, the needle  94  may pierce the elastomeric sheath  49 , and the needle  94  may insert into a cavity of the evacuated blood collection tube. In some embodiments, the holder  84  may include a BD VACUTAINER® one-use holder. In some embodiments, the holder  84  may include any suitable device configured to couple to a blood collection device or tube. 
     In some embodiments, the needle hub  18  may include the gas permeable vent  48 , which may be proximate the flash chamber  46 . In some embodiments, a location of the gas permeable vent  48  may vary. For example, the gas permeable vent  48  may be disposed near the proximal end  83  of the other extension tube  80 . In some embodiments, the needle hub  18  may include a luer adapter, which may replace the other extension tube  80 . 
     In some embodiments, in response to inserting the catheter  14  into the vasculature, blood may flow proximally into the needle lumen  22  at the distal tip  20 , then out of the needle lumen  22  through the first notch  26  into a space between an outer surface of the introducer needle  16  and an inner surface of the catheter  14 , and then into the needle lumen  22  through the second notch  28 . In some embodiments, after the blood flows into the needle lumen  22  through the second notch  28 , the blood may flow into the flash chamber  46  and/or through the other extension tube  80 . In some embodiments, the blood may then be collected in a blood collection device, such as, for example, the evacuated blood collection tube. In these and other embodiments, the seal formed by the seal element  72  may be intact. 
     The present invention may be embodied in other specific forms without departing from its structures, methods, or other essential characteristics as broadly described herein and claimed hereinafter. The described embodiments and examples are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope. 
     All examples and conditional language recited herein are intended for pedagogical objects to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Although implementations of the present inventions have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.