Patent Description:
The present disclosure generally relates to blood draw and administration of parenteral fluids to a patient, and particularly to systems and non claimed methods to reduce hemolysis in PIVC blood draw using a flow restriction device.

Catheters are commonly used for a variety of infusion therapies. For example, catheters may be used for infusing fluids, such as normal saline solution, various medicaments, and total parenteral nutrition, into a patient. Catheters may also be used for withdrawing blood from the patient.

A common type of catheter is an over-the-needle peripheral intravenous ("IV") catheter (PIVC). As its name implies, the over-the-needle catheter may be mounted over an introducer needle having a sharp distal tip. A catheter assembly may include a catheter hub, the catheter extending distally from the catheter hub, and the introducer needle extending through the catheter. 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.

For blood withdrawal or collecting a blood sample from a patient, a blood collection container may be used. The blood collection container may include a syringe. Alternatively, the blood collection container may include a test tube with a rubber stopper at one end. In some instances, the test tube has had all or a portion of air removed from the test tube so pressure within the test tube is lower than ambient pressure. Such a blood collection container is often referred to as an internal vacuum or a vacuum tube. A commonly used blood collection container is a VACUTAINER® blood collection tube, available from Becton Dickinson & Company.

The blood collection container may be coupled to the catheter. When the blood collection container is coupled to the catheter, a pressure in the vein is higher than a pressure in the blood collection container, which pushes blood into the blood collection container, thus filling the blood collection container with blood. A vacuum within the blood collection container decreases as the blood collection container fills, until the pressure in the blood collection container equalizes with the pressure in the vein, and the flow of blood stops.

Unfortunately, as blood is drawn into the blood collection container, red blood cells are in a high shear stress state and susceptible to hemolysis due to a high initial pressure differential between the vein and the blood collection container. Hemolysis may result in rejection and discard of a blood sample. The high initial pressure differential can also result in catheter tip collapse, vein collapse, or other complications that prevent or restrict blood from filling the blood collection container. Furthermore, blood spillage during and/or after blood draw commonly occurs.

The document <CIT> describes a blood-sampling tube that includes a first fluid-receiving chamber designed to receive fluid. This chamber is connected to at least one fluid channel. The fluid channel is equipped with a sensor device capable of measuring at least one biochemical function of the fluid passing through. The measurements taken by the sensor device can be accessed via a data interface integrated into the blood-sampling tube.

The document <CIT> describes an adapter featuring a distal end designed to couple with a catheter assembly and a proximal end equipped with a proximal connector for coupling to a blood collection device. Between the distal and proximal ends, a fluid pathway is present. This fluid pathway includes a non-linear portion, which can take on various shapes such as a coil, an S-shape, or other configurations.

According to the present invention there is provided a fluid restriction device comprising the features of claim <NUM>.

In some instances, the present disclosure provides a flow restriction device, comprising a housing comprising a first end portion, a second end portion, an inner surface forming a cavity between the first and second end portions, a first opening through the first end portion, and a second opening through the second end portions, and an insert body comprising a first end, a second end, an outer surface extending between the first and second ends, and an inner surface forming a fluid passage extending between the first and second ends, the fluid passage having a first opening through the first end of the insert body, a second opening through the second end of the insert body, and a third opening through the outer surface, wherein the insert body is positioned within the cavity with the first opening of the fluid passage fluidly coupled with the first opening of the housing, the second opening of the fluid passage fluidly coupled with the second opening of the housing, and the third opening obstructed by the inner surface of the housing.

In some instances, the present disclosure provides a peripheral intravenous catheter assembly configured to limit hemolysis during the drawing of blood from a patient, comprising a flow restriction device, comprising, a housing comprising a first end portion a first end portion, a second end portion, an inner surface forming a cavity between the first and second end portions, a first opening through the first end portion, wherein the first end portion is configured to couple to a catheter assembly, and the second end portion is configured to couple to a fluid collection device, an insert body comprising a first end, a second end, a longitudinal axis extending through the first and second ends, and an inner surface forming a fluid passage extending between the first and second ends, the fluid passage comprising a first portion that extends in a first direction away from the longitudinal axis, a second portion that extends in a second direction toward the longitudinal axis, and a third portion that extends in the first direction, wherein the insert body is positioned within the cavity with a first opening of the fluid passage fluidly coupled with the first opening of the housing, and a second opening of the fluid passage fluidly coupled with the second opening of the housing to limit hemolysis of blood drawn from a patient from the first end portion of the housing into the fluid collection device via the second end portion of the housing, a catheter hub having a proximal end and a distal end, and a fluid connector that fluidly couples the catheter hub with the flow restriction device.

Blood draw via a vascular access device has drawn increasing attention attributed to minimized needle sticks and improved operation efficiency as compared with traditional blood draw methods with venipuncture. Current blood draw using a peripheral intravenous catheter (PIVC) has seen some challenges, one of the most critical is hemolysis related blood quality. In particular, with currently existing PIVC products in the market, along with the standard connection (such as a short extension set and a needleless connector), and blood collection devices (such as a Vacutainer), the shear stress exerted onto blood cells tends to be on the verge of hemolyzing.

Various embodiments of the present disclosure are directed to providing systems and non claimed methods to address hemolysis in PIVC blood draw with a hemolysis reduction accessory (also referred to herein as a flow restriction device) which can be pre-attached to the PIVC and decrease a flow rate to reduce a risk of hemolysis. The hemolysis-reduction accessory is advantageously compatible with PIVC placement and does not necessitate change to any of the existing operations. The hemolysis-reduction accessory of the various embodiments described herein is potentially applicable to a wide variety of PIVC products, and compatible with existing blood collection devices and infusion disposables.

Various embodiments of the present disclosure focus on effective flow rate reduction with the add-on hemolysis-reduction accessory (also referred to herein as a flow restriction device) that regulates the overall flow rate of the entire fluid path as blood cells travel through. The flow restriction device can be either assembled with the PIVC or co-packaged with the PIVC. As such, there is no additional operation during catheter placement since the device can permit blood flashback. The clinician may connect a blood collection device to a port or opening of the accessory and can then draw blood to the intended volume. After blood draw, the clinician may disconnect and discard the flow restriction device and the blood collection device together. As such, this flow restriction device can be either for single blood draw or stay inline throughout indwell.

The flow restriction devices and associated blood collection systems of the various embodiments described herein additionally provide further advantages over currently existing blood collection systems. For example, add-on flow restriction devices described herein allow for hemolysis-reduction function to be integrated for PIVC blood draw. Further, the flow restriction devices described herein are compatible with PIVC placement and allow for seamless blood draw at insertion. Additionally, since the flow restriction devices are an add-on which can be easily incorporated without any changes to existing PIVC, there is minimal impact to clinical setting and operations.

<FIG> illustrates a vascular access device <NUM> including a peripheral intravenous catheter (PIVC) assembly <NUM> that includes a flow restriction device <NUM>, in accordance with some embodiments of the present disclosure. The flow restriction device <NUM> may be configured to reduce a likelihood of hemolysis during blood collection using the vascular access device <NUM>. In some embodiments, the vascular access device <NUM> may include a catheter assembly <NUM>. The catheter assembly <NUM> may include a catheter hub <NUM>, which may include a distal end <NUM>, a proximal end <NUM>, and a lumen extending through the distal end and the proximal end. The catheter assembly <NUM> may further include a catheter <NUM>, which may be secured within the catheter hub <NUM> and may extend distally from the distal end <NUM> of the catheter hub <NUM>. In some embodiments, the catheter assembly <NUM> may be a peripheral intravenous catheter (PIVC).

In some embodiments, the catheter assembly <NUM> may include or correspond to any suitable catheter assembly <NUM>. In some embodiments, the catheter assembly <NUM> may be integrated and include an extension tube <NUM>, which may extend from and be integrated with a side port <NUM> of the catheter hub <NUM>. A non-limiting example of an integrated catheter assembly is the BD NEXIVA™ Closed IV Catheter system, available from Becton Dickinson and Company. In some embodiments, a proximal end of the extension tube <NUM> may be coupled to an adapter, such as, for example, a Y-adapter <NUM>. In some embodiments, the flow restriction device <NUM> may be fluidly coupled to the Y-adapter <NUM>.

In some embodiments, the catheter assembly <NUM> may be non-integrated and may not include the extension tube <NUM>. In these and other embodiments, the flow restriction device <NUM> may be configured to couple to the proximal end <NUM> of the catheter hub <NUM> or another suitable portion of the catheter assembly <NUM>. In some embodiments, the flow restriction device <NUM> may be coupled directly to the catheter assembly <NUM>, eliminating the extension tube <NUM> and providing a compact catheter system.

<FIG> illustrates a perspective view of a flow restriction device <NUM>, in accordance with some embodiments of the present disclosure. <FIG> illustrates an exploded view of the flow restriction device <NUM> having a housing with a first end portion and a second end portion, and an insert body. <FIG> illustrates a perspective view of the insert body <NUM> of <FIG>. <FIG> and <FIG> illustrate a cross-sectional view of the flow restriction device of <FIG>, along line <NUM>-<NUM>.

As illustrated in <FIG>, with continued reference to <FIG>, in some embodiments, the flow restriction device <NUM> includes housing <NUM> with a first end portion <NUM> and a second end portion <NUM>. The first end portion <NUM> can be configured to couple to the catheter assembly <NUM>, and the second end portion <NUM> can be configured to couple to fluid collection device, such as a blood collection device <NUM>.

For example, the second end portion <NUM> may be integrated with the blood collection device <NUM> or monolithically formed with the blood collection device <NUM> as a single unit or piece. As another example, the second end portion <NUM> may be in the form of a female luer connector or another suitable connector, which may be coupled with a male luer portion of the blood collection device <NUM>. Further, the first end portion <NUM> may be in the form of a male luer connector or another suitable connector, which may be coupled with a catheter or a portion of catheter assembly.

The first end portion <NUM> may have an internal surface <NUM> forming a first opening <NUM>. The second end portion <NUM> may include an internal surface <NUM> forming a second opening <NUM> extending therethrough for coupling to a male luer portion of the blood collection device <NUM>. The second opening of the <NUM> of the second end portion may be fluidly connected to the first opening <NUM> of the first end portion via a cavity <NUM> formed by an inner surface of the housing.

In some embodiments of the present disclosure, the first end portion <NUM> of the housing can be formed as any of a male and/or female luer connector with the first opening <NUM> extending therethrough, and the second end portion <NUM> of the housing can be formed as the other of a male and/or female luer connector with the second opening <NUM> extending therethrough. The housing <NUM> can comprise a material that includes a thermoplastic polymer such as a polycarbonate or another material having similar properties.

In accordance with various embodiments of the present disclosure, the first end portion <NUM> can be integrally formed with the housing <NUM> to form a single monolithic piece, and the housing <NUM> can be coupled to the second end portion <NUM>. When the first and second end portions <NUM>, <NUM> are assembled or are integrally formed, the first opening <NUM> of the first end portion is fluidly coupled to the second opening of the second end portion through the cavity <NUM>.

The cavity <NUM> is configured to receive an insert body <NUM> therein. The insert body <NUM> directs a fluid flow between the first and second openings <NUM>, <NUM> of the housing while inducing a resistance to the fluid flow as it moves through the insert body <NUM>. By inducing a resistance to the fluid flow, the rate of fluid flow is reduced as the fluid moves through the insert body <NUM>. Reducing the flow rate of a fluid, such as blood, through the flow restriction device <NUM> can reduce the hemolysis index of the blood.

The insert body <NUM> has a first end <NUM>, a second end <NUM>, and an inner surface <NUM> forming a fluid passage <NUM> that extends through the first and second ends <NUM>, <NUM>. The fluid passage <NUM> extends along a path between the first and second ends <NUM>, <NUM> of the body, which is configured to reduce a rate of fluid flow through the insert body <NUM>. A perspective view of the insert body <NUM> is illustrated in <FIG> with the body shown as being transparent to permit the fluid passage <NUM> to be visible in conjunction with the present disclosure.

In some embodiments of the present disclosure, the first end <NUM> of the insert body and the second end <NUM> of the insert body form proximal-most and distal-most surfaces of the body, respectively. The insert body <NUM> can also define a longitudinal axis A1 that extends through the first and second ends <NUM>, <NUM>. The fluid passage <NUM> spans between the first and second ends <NUM>, <NUM> of the insert body, and is configured to extend in more than one direction along a path between the first and second ends <NUM>, <NUM>. Because the path extends in more than one direction, the fluid passage <NUM> extends indirectly between the first and second ends <NUM>, <NUM> of the insert body. The indirect path between the first and second ends <NUM>, <NUM> of the body can have a length that is greater than a distance between the first and second ends <NUM>, <NUM> of the body.

The fluid passage <NUM> includes a first opening <NUM> through the first end <NUM> of the insert body, and a second opening <NUM> through the second end <NUM> of the insert body. Between the first and second openings <NUM>, <NUM>, the fluid passage <NUM> can include a third opening <NUM> through an outer surface <NUM> of the insert body. The third opening <NUM> extends through the outer surface <NUM> at a location that is between the first and second ends <NUM>, <NUM>. The location of the third opening <NUM> can be spaced apart from the first and second ends <NUM>, <NUM> such that an outermost circumference of any of the first and second ends <NUM>, <NUM> is uninterrupted by the third opening <NUM>.

In some embodiments of the present disclosure, the fluid passage <NUM> can also include a fourth opening <NUM> through the outer surface <NUM> of the insert body. The third and fourth openings <NUM>, <NUM> are positioned along the outer surface <NUM> of the insert body relative to the longitudinal axis A1. In some embodiments of the present disclosure, the third and fourth openings <NUM>, <NUM> are positioned along the outer surface <NUM> of the insert body such that the third and fourth openings <NUM>, <NUM> are spaced apart in a radial direction around the longitudinal axis A1 of the insert body. For example, the third and fourth openings <NUM>, <NUM> can be spaced apart by an angle of between approximately <NUM> degrees and approximately <NUM> degrees, relative to the longitudinal axis A1. In some aspects of the present disclosure, the third and fourth openings <NUM>, <NUM> are spaced apart by an angle of approximately <NUM> degrees.

The fluid passage <NUM> can also include a fifth opening <NUM> through the outer surface <NUM> of the insert body. In such embodiments, the third and fifth openings <NUM>, <NUM> can be spaced apart in a direction along the longitudinal axis A1 of the insert body, with the fourth opening <NUM> positioned between the third and fifth openings <NUM>, <NUM>.

The insert body <NUM> can be configured with the third, fourth, and fifth openings <NUM>, <NUM>, <NUM> positioned in any radial orientation relative to each other. In some embodiments of the present disclosure, such as the embodiment illustrated in <FIG> and <FIG>, the third and fifth openings <NUM>, <NUM> are radially aligned relative to the longitudinal axis A1, and the fourth opening <NUM> is spaced apart in a radial direction around the longitudinal axis A1 by an angle. The fourth opening <NUM> can be spaced apart from any of the third and fifth openings <NUM>, <NUM> by an angle of between approximately <NUM> degrees and approximately <NUM> degrees. In some aspects of the present disclosure, the fourth opening <NUM> is spaced apart of the third and fifth openings <NUM>, <NUM> by an angle of approximately <NUM> degrees.

Referring to <FIG>, the fluid passage <NUM> can include a first portion <NUM> that extends in a first direction D1 away from the longitudinal axis A1. A second portion <NUM> of the fluid passage extends from the first portion <NUM> in a second direction D2 toward the longitudinal axis A1. The second portion <NUM> of the fluid passage can extend past the longitudinal axis A1, and a third portion of the fluid passage can extend from the second portion <NUM> in the first direction D1 toward the longitudinal axis A1.

In some embodiments of the present disclosure, the fluid passage <NUM> comprises a fourth portion <NUM> that extends from the third portion <NUM> in a second direction D2 toward the longitudinal axis A1. In such embodiments, the second opening <NUM> of the fluid passage is fluidly coupled to the fourth portion <NUM>.

The change in direction of the fluid passage <NUM> between the first and second ends <NUM>, <NUM> of the insert body can be configured by an angle between one or more portion of the fluid passage <NUM>. In some instances, the fluid passage <NUM> can have a change in direction by an angle between approximately <NUM> degrees and approximately <NUM> degrees. The changes in direction of the fluid passage <NUM> can form a line that represents a periodic wave, such as a square wave. The changes in direction of the fluid passage are optimized to reduce pressure of a fluid, e.g., blood, moving through the fluid passage <NUM> by inducing resistance to the fluid. Since the decreased blood flow rate causes a reduction in shear stress experienced by the red blood cells of the blood, a risk of hemolysis during blood collection may advantageously be reduced.

In some embodiments of the present disclosure, the fluid passage <NUM> includes eight changes in direction, where each change in direction is approximately <NUM> degrees. Referring to <FIG> and <FIG>, an angle between any of the first, second, third, and fourth portions <NUM>, <NUM>, <NUM>, <NUM>, and any of the third, fourth, and fifth openings <NUM>, <NUM>, <NUM> of the fluid passage <NUM> is illustrated as approximately <NUM> degrees. An angle AA between the fluid passage <NUM> at the first opening <NUM> and the first portion <NUM> is approximately <NUM> degrees, an angle AB between the first portion <NUM> and the fluid passage <NUM> along the first opening <NUM> is approximately <NUM> degrees, an angle AC between the fluid passage <NUM> along the third opening <NUM> and the second portion <NUM> is approximately <NUM> degrees, an angle AD between the second portion <NUM> and the fluid passage <NUM> along the fourth opening <NUM> is approximately <NUM> degrees, an angle AE between the fluid passage <NUM> along the fourth opening <NUM> and the third portion <NUM> is approximately <NUM> degrees, an angle AF between the third portion <NUM> and the fluid passage <NUM> along the fifth opening <NUM> is approximately <NUM> degrees, an angle AG between the fluid passage <NUM> along the fifth opening <NUM> and the fourth portion <NUM> is approximately <NUM> degrees, and an angle AE between the fourth portion <NUM> and the fluid passage <NUM> at the second opening <NUM> is approximately <NUM> degrees.

Referring to <FIG>, movement of a fluid through the flow restriction device <NUM> and along the path of the fluid passage <NUM> is illustrated by arrows. Although the arrows illustrate movement of a fluid through the flow restriction device <NUM> in a direction from the first end portion <NUM> to the second end portion <NUM>, it should be understood that the present disclosure contemplates that a fluid can move through the flow restriction device <NUM> in a direction from the second end portion <NUM> to the first end portion <NUM>.

When the insert body <NUM> is positioned within the cavity <NUM> of the housing, at least a portion of the outer surface <NUM> of the insert body engages against the inner surface of the housing that forms the cavity <NUM>. A segment of the fluid passage <NUM> at any of the third, fourth, and fifth openings <NUM>, <NUM>, <NUM> is at least partially formed by the inner surface of the housing <NUM>.

The housing <NUM>, or portion thereof, can comprise a transparent material to permit observation of a fluid in the fluid passage <NUM>. A housing comprising a transparent material is illustrated in <FIG>, where the third opening <NUM>, the fourth opening <NUM> (not shown), and the fifth opening <NUM> of the fluid passage are visible through the outer surface of the housing.

In some embodiments, a portion of the housing <NUM> comprises a transparent material forming a window through the housing. The window can be positioned between the first and second openings <NUM>, <NUM> of the housing, at a location the is aligned with any of the third, fourth, and fifth openings <NUM>, <NUM>, <NUM> of the insert body positioned in the cavity <NUM> of the housing. In some embodiments, the housing <NUM> comprises three windows, each aligned with a respective one of the third, fourth, and fifth openings <NUM>, <NUM>, <NUM> of the insert body. In yet other embodiments of the present disclosure, the window can extend around a circumference of the housing such that the third, fourth, and/or fifth openings <NUM>, <NUM>, <NUM> are each longitudinally aligned a window in any rotational orientation of the insert body relative to the housing.

An insert body <NUM> can be configured, in some embodiments of the present disclosure, to include a material that is flexible, relative to other portions of the insert body or the housing. The flexible material can provide a seal between the insert body and the housing. The insert body <NUM> can be partially or entirely formed of the flexible material, or the insert body <NUM> is over-molded with the flexible material. In some aspects of the present disclosure, the flexible material is an elastomer, such as silicone rubber, or a similar material that can provide a fluid seal between the insert body and the housing.

Referring to <FIG>, an insert body <NUM> formed of a silicone material is illustrated. The silicone extends along the outer surface of the insert body <NUM> and can engage against an inner surface of the housing <NUM> when the insert body <NUM> is positioned with in the cavity <NUM> of the housing. Engagement of the silicone <NUM> against the inner surface of the housing <NUM>, as illustrated in <FIG>, provides a seal that can resist a fluid from moving out of an opening of the fluid passage <NUM>, such as the third, fourth, and fifth openings <NUM>, <NUM>, <NUM>.

In some embodiments of the present disclosure, an insert body <NUM> can include a wall <NUM> that extends in a direction away from the outer surface of the insert body, as illustrated in <FIG>. The wall <NUM> is configured to engage against an inner surface of the housing <NUM> when the insert body <NUM> is positioned with in the cavity <NUM> of the housing to provide a seal that resists a fluid from moving out of an opening of the fluid passage <NUM>.

The wall <NUM> is positioned to extend around an opening of the fluid passage <NUM>, such as the third, fourth, and fifth openings <NUM>, <NUM>, <NUM>. The wall <NUM> can have a height that extends in a direction away from an outer surface of the insert body, and a length that extends around the opening of the fluid passage <NUM>. In some aspects, the insert body <NUM> includes a first wall <NUM> that extends around the third opening <NUM> of the insert body, a second wall <NUM> that extends around the fifth opening <NUM> of the insert body, and a third wall that extends around the fourth opening of the insert body.

When the insert body <NUM> is positioned in the cavity <NUM> of the housing, as illustrated in <FIG>, any of the walls <NUM>, <NUM> of the insert body can engage against an inner surface of the housing <NUM> to resist a fluid from moving out of an opening of the fluid passage <NUM>, such as the third, fourth, and fifth openings <NUM>, <NUM>, <NUM>. In some embodiments of the present disclosure, a wall <NUM>, <NUM> is compressed or crushed when the insert body <NUM> is positioned in the housing <NUM>.

Another aspect of the flow restriction device <NUM> of the present disclosure is the optimization of manufacturability for insert body <NUM>, <NUM>, <NUM>. The insert body <NUM>, <NUM>, <NUM> can be manufactured using an efficient molding process in which core pins are positioned in a mold to form the fluid passage <NUM>. The core pins can be positioned to form the fluid passage while permitting easy removal of the core pins after the insert body is molded, and which may not cause damage to the fluid passage or core pins. In some aspects of the present disclosure, each core pin comprises two protrusions, where each protrusion is configured to form at least a portion of the fluid passage <NUM>.

Claim 1:
A flow restriction device (<NUM>), comprising:
a housing (<NUM>) comprising a first end portion (<NUM>), a second end portion (<NUM>), an inner surface forming a cavity (<NUM>) between the first and second end portions, a first opening (<NUM>) through the first end portion, and a second opening (<NUM>) through the second end portions; and
an insert body (<NUM>, <NUM>, <NUM>) comprising a first end (<NUM>), a second end (<NUM>), a longitudinal axis (A1) extending through the first and second ends, and an inner surface (<NUM>) forming a fluid passage (<NUM>) extending between the first and second ends, the fluid passage comprising a first portion (<NUM>) that extends in a first direction (D1) away from the longitudinal axis (A1), a second portion (<NUM>) that extends in a second direction (D2) toward the longitudinal axis (A1), a third portion (<NUM>) that extends in the first direction (D1);
wherein the insert body (<NUM>, <NUM>, <NUM>) is positioned within the cavity (<NUM>) with a first opening (<NUM>) of the fluid passage fluidly coupled with the first opening (<NUM>) of the housing and a second opening (<NUM>) of the fluid passage fluidly coupled with the second opening (<NUM>) of the housing,
characterized by
a third opening (<NUM>) of the fluid passage formed by a fourth portion (<NUM>) of the fluid passage that extends through an outer surface (<NUM>) of the insert body, and a fourth opening (<NUM>) of the fluid passage formed by a fifth portion of the fluid passage that extends through the outer surface (<NUM>) of the insert body, wherein the fourth opening (<NUM>) is spaced apart from the third opening (<NUM>).