Patent Description:
The catheter may include an over-the-needle peripheral intravenous ("IV") catheter. In this case, the catheter may be mounted over an introducer needle having a sharp distal tip. The catheter and the introducer needle may be assembled so that the distal tip of the introducer needle extends beyond the distal tip of the catheter with the bevel of the needle facing up away from skin of the patient. The catheter and introducer needle are generally inserted at a shallow angle through the skin into vasculature of the patient.

Blood withdrawal or infusion using the catheter may be difficult for several reasons, particularly when a dwell time of the catheter within the vasculature is more than one day. When the catheter is left inserted in the patient for a prolonged period of time, the catheter or vein may be more susceptible to narrowing, collapse, kinking, blockage by debris (e.g., fibrin, thrombus, or platelet clots), and adhering of a tip of the catheter to the vasculature. Due to this, infusion may be unsuccessful. Also due to this, the catheter is often used for acquiring a blood sample at a time of catheter placement, but the catheter is less frequently used for acquiring a blood sample during the catheter dwell period. Therefore, when a blood sample is required, an additional needle stick is often needed to provide vein access for blood collection, which may be painful for the patient and result in higher material costs.

<CIT> discloses an apparatus for inserting a catheter device. <CIT> discloses a system for facilitating instrument delivery through a peripheral intravenous catheter. <CIT> discloses a device for catheter placement within a vein. <CIT> discloses an anchoring guidewire. <CIT> discloses a stent delivery system. <CIT> discloses a guidewire which obtains a sufficient load at a distal end.

The present disclosure relates generally to spring-based devices and systems to facilitate vascular access. A first aspect of the invention relates to an extension set to couple to a vascular access device, the extension set comprising: a distal connector; a proximal connector; a housing, comprising a distal end coupled to the distal connector and a proximal end coupled to the proximal connector; a tube disposed within the housing and configured to move distally such that a distal end of the tube is distal to the distal connector; and a coil spring bonded to and disposed within the tube, wherein a distal end of the coil spring is distal to the distal end of the tube or the coil spring is configured to extend distally such that the distal end of the coil spring is distal to the distal end of the tube. A second aspect of the invention relates to a catheter system, comprising: a catheter assembly, comprising: a catheter adapter, comprising a distal end, a proximal end, and a lumen extending through the distal end and the proximal end; and a catheter extending distally from the distal end of the catheter adapter; and a coil spring bonded to the catheter and extending through a distal opening of the catheter.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive, 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 disclosure. The following detailed description is, therefore, not to be taken in a limiting sense.

Referring now to <FIG>, an extension set <NUM> is configured to couple to a vascular access device. The extension set <NUM> includes a distal connector <NUM> and a proximal connector <NUM>. The extension set <NUM> includes a housing <NUM>, which includes a distal end <NUM> coupled to the distal connector <NUM> and a proximal end <NUM> coupled to the proximal connector <NUM>. The extension set <NUM> includes a sleeve <NUM> disposed within the housing <NUM> and configured to move distally such that a distal end <NUM> of the sleeve <NUM> is distal to the distal connector <NUM>. In these embodiments, the sleeve <NUM> may be configured to move distally in response to flushing of a liquid or air through the housing <NUM> in a distal direction. In some embodiments, a vent may allow expulsion of air from the extension set <NUM>.

The sleeve <NUM> includes a tube, which may include an open distal end, as illustrated, for example, in <FIG>. In some embodiments, the sleeve <NUM> may include the tube, which may include side holes and/or a closed distal tip. In some embodiments, the sleeve <NUM> may include a probe or a sensor. The extension set <NUM> includes a coil spring (<NUM>) bonded to and disposed within the sleeve <NUM>. In some embodiments, the coil spring may be constructed of metal or another suitable material. In some embodiments, the coil spring may include a central guidewire extending there through or one or more off-center guidewires extending there through. In some embodiments, the proximal connector <NUM> may be coupled to a needleless connector <NUM>.

Referring now to <FIG>, in some embodiments, an infusion device <NUM>, such as, for example, a syringe, may be coupled to the proximal connector <NUM>. In some embodiments, the infusion device <NUM> may be directly coupled to the proximal connector <NUM>. In other embodiments, the needleless connector <NUM> may be disposed between the infusion device <NUM> and the proximal connector <NUM>. In some embodiments, the needleless connector <NUM> may be coupled to the infusion device <NUM>. In some embodiments, the infusion device <NUM> may be activated (such as, for example, a plunger of the syringe being depressed) to flush the liquid within the infusion device <NUM> through the housing <NUM> in the distal direction and/or a catheter assembly <NUM> coupled to the distal connector <NUM>.

In some embodiments, a catheter system <NUM> may include the catheter assembly <NUM> and the extension set <NUM>. In some embodiments, the catheter assembly <NUM> may include a catheter adapter <NUM>. In some embodiments, the catheter adapter <NUM> may include a distal end <NUM>, a proximal end <NUM>, and a lumen <NUM> extending through the distal end <NUM> of the catheter adapter <NUM> and the proximal end <NUM> of the catheter adapter <NUM>. In some embodiments, the catheter assembly <NUM> may include the catheter <NUM>, which may extend distally from the distal end <NUM> of the catheter adapter <NUM>. In some embodiments, the catheter <NUM> may include a peripheral intravenous catheter, a peripherally-inserted central catheter, or a midline catheter.

In some embodiments, the catheter assembly <NUM> may include another extension set <NUM>, which may be integrated with the catheter adapter <NUM>. In some embodiments, the other extension set <NUM> may include an extension tube <NUM>, which may be integrated with a side port <NUM> of the catheter adapter <NUM> disposed between the distal end <NUM> and the proximal end <NUM>. In some embodiments, an adapter <NUM> may be coupled to a proximal end of the extension tube <NUM>. In some embodiments, the distal connector <NUM> may be coupled to the adapter <NUM>. In some embodiments, the distal connector <NUM> may be coupled to the proximal end <NUM> of the catheter adapter <NUM>, and the sleeve <NUM> may be disposed in generally straight line within the catheter adapter <NUM>.

Referring now to <FIG>, in some embodiments, the distal connector <NUM> and/or the housing <NUM> may include an inner diameter <NUM>. In some embodiments, the housing <NUM> may be rigid, semi-rigid, or flexible. In some embodiments, an outer surface of the sleeve <NUM> may include a feature <NUM>. In some embodiments, the feature <NUM> may be integrated or monolithically formed as a single unit with the sleeve <NUM>. In some embodiments, the feature <NUM> may be a separate component from the sleeve <NUM> and coupled to the sleeve <NUM>. In some embodiments, the feature <NUM> may be wedge-shaped or another suitable shape. In some embodiments, the sleeve <NUM> may be retracted using a retraction mechanism that pinches down on the sleeve <NUM> and the feature <NUM>. In some embodiments, the retraction mechanism may be disposed on the housing <NUM>. The retraction mechanism may be further described in <CIT>.

In some embodiments, the feature <NUM> may include an outer diameter <NUM>. In some embodiments, the outer diameter <NUM> of the feature <NUM> may be greater than the inner diameter <NUM> such that the feature <NUM> is prevented from moving distally through the distal connector <NUM>. In some embodiments, the sleeve <NUM> may include an inner diameter <NUM>. In some embodiments, a proximal portion of the instrument <NUM> may include an outer diameter <NUM>. In some embodiments, the outer diameter <NUM> of the proximal portion of the instrument <NUM> may be greater than the inner diameter <NUM> of the sleeve <NUM> such that the proximal portion of the instrument <NUM> is prevented from moving distal to the inner diameter <NUM> of the sleeve <NUM>.

In some embodiments, in response to activating the infusion device <NUM> or flushing, the sleeve <NUM> and the instrument <NUM> may be moved from a proximal position to a distal position, illustrated, for example, in <FIG>. In some embodiments, in response to the sleeve <NUM> and the instrument <NUM> being in the distal position, the sleeve <NUM> may be wedged within the distal connector <NUM> in an interference fit due to the outer diameter <NUM> being greater than the inner diameter <NUM> and/or the instrument <NUM> may be wedged within the distal end <NUM> of the sleeve <NUM> in an interference fit due to the outer diameter <NUM> being greater than the inner diameter <NUM>. In some embodiments, in response to the sleeve <NUM> and the instrument <NUM> being in the distal position, the sleeve <NUM> and the instrument <NUM> may extend distal to a distal end <NUM> of the catheter <NUM>. In some embodiments, the distal end <NUM> of the instrument <NUM> may be between <NUM> and about <NUM> beyond the distal end of the catheter <NUM>. In some embodiments, the distal end <NUM> of the instrument <NUM> may be greater than <NUM> beyond the distal end of the catheter <NUM>. In some embodiments, an outer diameter <NUM> of the distal end <NUM> of the instrument <NUM> may be less than the outer diameter <NUM> of the proximal portion of the instrument <NUM>.

Referring now to <FIG>, in some embodiments, the instrument <NUM> may create a fluid path for blood to flow into the catheter <NUM> and the catheter assembly <NUM>. In some embodiments, the infusion device <NUM> may also act as a blood collection device (such as, for example, by retracting the plunger) or any other suitable blood collection device (such as, for example, a VACUTAINER® or a VACUTAINER® LUER-LOK™, available from Becton Dickinson and Company of Franklin Lakes, New Jersey) may be coupled to the extension set <NUM> to collect blood from the patient. In some embodiments, the sleeve <NUM> may be soft, which may decrease a likelihood of the sleeve <NUM> damaging the vasculature. In some embodiments, a durometer of the sleeve <NUM> may be less than a durometer of the catheter <NUM>. In some embodiments, the sleeve <NUM> creates an isolated or closed fluid path for blood flow and reduces a risk of contamination of the blood due to drug adsorption in the catheter assembly <NUM>. In some embodiments, the catheter <NUM> may serve as the fluid path in addition or as an alternative to the sleeve <NUM>. In some embodiments, the sleeve <NUM> may extend through the catheter <NUM> and the catheter adapter <NUM>.

In some embodiments, a pitch of the instrument <NUM> may vary. In some embodiments, the instrument <NUM> may include a tight pitch proximate a distal opening <NUM> of the sleeve <NUM> and/or adjacent the distal end of the catheter <NUM>. In some embodiments, the tight pitch may block obstruction from fibrin sheath, thrombus, or a vein wall under vacuum pressure when the blood collection device is activated. In some embodiments, the tight pitch may prevent collapse of the catheter <NUM> under vacuum pressure when the blood collection device is activated. In some embodiments, a pitch of the instrument <NUM> may be uniform. In some embodiments, the instrument <NUM> may include a more open pitch proximal to the tight pitch, which may facilitate blood flow and an increased blood flow rate in comparison to a closed sleeve or the tight pitch.

In some embodiments, the instrument <NUM> may be coupled to a guidewire (not illustrated), which may extend through the instrument <NUM>. In some embodiments, the distal end <NUM> of the instrument <NUM> may be rounded or bent, which may prevent trauma to the vein wall.

Referring now to <FIG>, an extension set <NUM> is illustrated, according to some embodiments. In some embodiments, the extension set <NUM> may be similar or identical to the extension set <NUM> in terms of one or more features and/or operation. In some embodiments, the distal end <NUM> of the instrument <NUM> may be distal to the distal end <NUM> of the sleeve <NUM>. In these and other embodiments, the instrument <NUM> may be coupled to the sleeve <NUM>. The coil spring is bonded to the sleeve <NUM>. In some embodiments, a guidewire (see, for example, the guidewire <NUM> of <FIG> or the guidewire <NUM> of <FIG>) may be coupled to and/or may extend through the instrument <NUM>.

As illustrated in <FIG>, in some embodiments, the sleeve <NUM> may include a variable outer diameter and a corresponding variable inner diameter. In some embodiments, the variable outer diameter and the corresponding variable inner diameter may facilitate greater blood flow through the sleeve <NUM> in response to the sleeve <NUM> being in the distal position. In some embodiments, the outer diameter of the sleeve <NUM> may increase in response to a diameter of an internal geometry of the catheter assembly <NUM> increasing. In some embodiments, the instrument <NUM> may include two tight pitch sections and a more open pitch section between the two tight pitch sections.

Referring now to <FIG>, in some embodiments, the sleeve <NUM> may include one or more side holes <NUM>, which may facilitate a fluid path for blood draw. In some embodiments, a guidewire <NUM> may extend through the instrument <NUM> and provide stiffening to reduce a likelihood of collapse of the catheter <NUM>. As mentioned, in some embodiments, the distal end <NUM> of the instrument <NUM> may be rounded or bent, which may prevent trauma to the vein wall. In some embodiments, the instrument <NUM> and/or the sleeve <NUM> may include staged deployment, which may be further described, for example, in <CIT>, entitled "EXTENSION HOUSING A SLEEVE OR INTRAVENOUS CATHETER," <CIT>, entitled "INSTRUMENT DELIVERY DEVICE HAVING A ROTARY ELEMENT," <CIT>, entitled "MULTI-DIAMETER CATHETER AND RELATED DEVICES AND METHODS," <CIT>, entitled "DELIVERY DEVICE FOR A VASCULAR ACCESS INSTRUMENT," <CIT>, entitled "SYRINGE-BASED DELIVERY DEVICE FOR A VASCULAR ACCESS INSTRUMENT," <CIT>, entitled "CATHETER DELIVERY DEVICE AND RELATED SYSTEMS AND METHODS," and <CIT>, entitled "VASCULAR ACCESS INSTRUMENT HAVING A FLUID PERMEABLE STRUCTURE, AND RELATED DEVICES AND METHODS.

Referring back to <FIG>, in some embodiments, the catheter system <NUM> may include a particular guidewire <NUM>, which may bend to form the instrument <NUM> in response to activation by heat or moisture. <FIG> is a cross-sectional view of a distal end of the catheter system of <FIG>, illustrating the heat-activated or moisture-activated guidewire prior to heat or moisture activation, according to some embodiments. In some embodiments, the guidewire <NUM> may be inserted through the catheter assembly <NUM> to reduce obstruction from fibrin sheath or thrombus. In some embodiments, the guidewire <NUM> and/or the instrument <NUM> may be constructed of a shape-memory polymer or alloy.

Referring now to <FIG>, in some embodiments, a straightener sleeve <NUM> may be disposed within the catheter <NUM>. In some embodiments, a guidewire <NUM> may be disposed within the straightener sleeve <NUM>, which may extend through the catheter assembly <NUM>. In some embodiments, in response to removal of a distal end <NUM> of the guidewire <NUM> from the straightener sleeve <NUM>, the guidewire <NUM> may be configured to bend into the instrument <NUM>. In some embodiments, the guidewire <NUM> may be configured to advance distally with respect to the straightener sleeve <NUM> for blood draw. In some embodiments, in response to the guidewire <NUM> advancing distally beyond a distal end of the straightener sleeve <NUM>, the guidewire <NUM> may automatically bend into the instrument. In some embodiments, the straightener sleeve <NUM> may be configured to retract proximally with respect to the guidewire <NUM> for blood draw. In some embodiments, in response to the straightener sleeve <NUM> being retracted proximally with respect to the guidewire <NUM>, the guidewire <NUM> may automatically bend into the instrument <NUM>.

Referring now to <FIG>, in some embodiments, the catheter system <NUM> includes the coil spring <NUM>, which is bonded to the catheter and extends through the distal opening <NUM> of the catheter <NUM>. In some embodiments, a pitch of a portion of the instrument <NUM> proximate the distal opening <NUM> of the catheter <NUM> may be less than a pitch of another portion of the instrument <NUM> proximal to the distal opening <NUM> of the catheter <NUM>. In some embodiments, the catheter system <NUM> may include a guidewire <NUM>, which may extend through the instrument <NUM>. In some embodiments, the guidewire <NUM> may include an obstruction such as a rounded nose, which may block fluid from flowing through a center of the instrument <NUM> to prevent clogging of the instrument <NUM> with thrombus in response to insertion of the catheter <NUM> into vasculature of the patient. In these and other embodiments, an outer surface of the guidewire <NUM> may contact an inner surface of the instrument <NUM> all or a portion of a length of the instrument <NUM> to prevent fluid from flowing between the instrument <NUM> and the guidewire <NUM>.

In some embodiments, the catheter system <NUM> may include a connector <NUM> coupled to the catheter assembly <NUM>. For example, the connector <NUM> may be coupled to the adapter <NUM> or the proximal end <NUM> of the catheter adapter <NUM>. In some embodiments, the instrument <NUM> may be coupled to the connector <NUM> and may extend distally from the connector <NUM> through the catheter <NUM>. In some embodiments, the guidewire <NUM> may be coupled to another connector <NUM>, which may be coupled to the connector <NUM>. In some embodiments, the guidewire <NUM> may be removable from the catheter system <NUM>. In some embodiments, the guidewire <NUM> may be removed from the catheter system <NUM> for blood draw or infusion.

Referring now to <FIG>, in some embodiments, another instrument <NUM> may extend through the distal opening <NUM> of the catheter <NUM>. In some embodiments, the instrument <NUM> and the other instrument <NUM> may be wound together such that there is limited room for thrombus or other obstructions to enter the catheter assembly <NUM> during insertion of the catheter <NUM> into the vasculature of the patient. In some embodiments, the instrument <NUM> and the other instrument <NUM> may be concentric and may include a central axis extending through the instrument <NUM> and the other instrument <NUM>.

In some embodiments, the other instrument <NUM> may be configured to rotate about the central axis such that a distal end <NUM> of the other instrument <NUM> and the distal end <NUM> of the instrument <NUM> are spaced apart. For example, the other instrument <NUM> may be configured to rotate about the central axis and advance distally with respect to the instrument <NUM>. In some embodiments, the instrument <NUM> and the other instrument <NUM> may be nested together such that they contact each other and one is wound with respect to the other. As another example, the other instrument <NUM> may be configured to rotate about the central axis and retract proximally with respect to the instrument <NUM>. In some embodiments, the rotation of the other instrument <NUM> about the central axis and movement of the other instrument <NUM> in a distal direction or a proximal direction with respect to the instrument <NUM> may open a fluid pathway through the instrument <NUM> and the other instrument <NUM> for blood draw or infusion, as illustrated, for example, in <FIG>.

Referring now to <FIG>, in some embodiments, the connector <NUM> may be coupled to the proximal end <NUM> of the catheter adapter <NUM>. In some embodiments, the instrument <NUM> may be coupled to the connector <NUM> and may extend distally from the connector <NUM> in a generally straight line through the catheter <NUM>. In some embodiments, the instrument <NUM> may include the coil spring. In some embodiments, the coil spring may include a central guidewire extending there through or one or more off-center guidewires extending there through. In some embodiments, the instrument <NUM> may include a tube, which may include side holes and/or a closed distal tip. In some embodiments, the instrument <NUM> may include a probe or a sensor.

Claim 1:
An extension set (<NUM>) to couple to a vascular access device, the extension set comprising:
a distal connector (<NUM>);
a proximal connector (<NUM>);
a housing (<NUM>), comprising a distal end (<NUM>) coupled to the distal connector and a proximal end (<NUM>) coupled to the proximal connector (<NUM>);
a tube (<NUM>) disposed within the housing and configured to move distally such that a distal end (<NUM>) of the tube is distal to the distal connector (<NUM>); and
a coil spring (<NUM>) bonded to and disposed within the tube (<NUM>), wherein a distal end (<NUM>) of the coil spring is distal to the distal end (<NUM>) of the tube (<NUM>) or the coil spring (<NUM>) is configured to extend distally such that the distal end (<NUM>) of the coil spring is distal to the distal end (<NUM>) of the tube (<NUM>).