The present invention relates to catheterization systems and methods for accessing anatomical spaces in a body, and, more particularly, to the simultaneous flushing of multi-catheter systems.
Many medical procedures utilize catheters. Catheters are typically elongated tubular structures that provide a working channel for accessing a patient's anatomical spaces. Although catheters may be the best and safest treatment option for many diseases, they are not risk free. The working channel of a catheter permits easy access to not only medical devices but also to ambient air. Catheters pose a major risk of introducing an air embolism. For instance, a 15 French (5 mm diameter) catheter sheath open to ambient air, in some scenarios, may allow 300 cc of air to enter the vascular system in only half a second. Although small volumes of air in the venous system may be asymptomatic, only 200 to 300 cc of air in the arterial system may be fatal.
Air embolisms are avoided, at least in part, by priming the catheter(s) with a fluid flush that expels air from any internal cavities of the catheter(s). In one scenario, a patient with an ischemic stroke is admitted to an emergency room. The physician must determine the location of the blood clot(s) and then select appropriately sized catheters to reach it. Each individual catheter must then be removed from its packaging and individually flushed with saline fluid to purge the catheters of air. This is a time-consuming process that takes up valuable time during many life-threatening and time sensitive procedures. In the case of ischemic stroke, the clot is cutting off blood flow to a portion of the brain. Although brain tissue may recover from small time periods of ischemia, an untreated occlusion eventually leads to the death of brain tissue. Thus, every second counts during an ischemic stroke procedure and time spent individually flushing catheters may be time that a patient's brain is suffering irreparable injury.
It is therefore an object of the present invention to improve flushing efficiency for multi-catheter systems, which can accelerate preparation during time sensitive and life-threatening procedures.
The present invention is embodied by a catheter or catheter component that includes a flush segment(s) comprised of one or more flush ports. The flush segment(s) is generally positioned along a length of the catheter body. Preferably, the flush segment enables radial fluid communication between a lumen of an inner catheter and an annular lumen of an adjacent or outer catheter, e.g. intraluminal fluid communication.
In one example, the present invention is embodied by a flushing catheter that is integrated with one or more flush segments. (
In one use case, an inner flushing catheter is placed inside an outer catheter to form a multi-catheter system. (
The novel flush segment(s) of the present invention improves the efficiency of catheterization procedures by reducing the number of preparation steps. A flush segment enables a multi-catheter system to be flushed of air with a single act of flushing through a single injection port. Typically, multi-catheter systems require several steps of flushing, either every catheter is flushed individually and then nested together or every catheter includes an independent injection port and each must be individually flushed. The present invention eliminates the need for individual flushing. The novel flush ports of the present invention enable a single step of flushing to flush two or more catheters simultaneously.
A flushing catheter may be comprised of a catheter body with a length that extends through a proximal region, a central region, and a distal region of the flushing catheter. The catheter body at least partially encloses a lumen that extends between a proximal end and a distal end of the flushing catheter, wherein the lumen has a single injection port. The flushing catheter includes a flush segment having a length and one or more flush ports, wherein the flush segment is located along the length of the catheter body. The flush ports may be embodied by a variety of geometries and configurations. The flush ports may be at least partially restrictive over some types of fluid flow. A flushing catheter may include fastening mechanisms for interlocking to smaller and larger catheters and catheter components.
A flushing catheter subcomponent may be comprised of a fluid channel having a lumen and a length that extend between a first end and a second end. The first end and the second end are configured for attachment to either a catheter hub or a catheter body. The flushing catheter subcomponent includes a flush segment having a length and one or more flush ports, wherein the flush segment is located along the length of the fluid channel. The flushing catheter subcomponent's lumen enables fluid communication at a distal terminus and the flush segment enables fluid communication to, at least, an external space adjacent to and along the length of the flush segment.
A flushing catheter may include a tapered distal end and tip shape that improves navigation in tortuous vasculature. A flushing catheter may include thick walls in at least some regions of the catheter body.
Background Art includes U.S. Pat. Nos. 5,207,648; 5,425,723; 5,800,408; and US2004/0097880.
All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.
The novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:
The present invention may be best understood through the following detailed description and the related illustrations. In this description, like numbers refer to similar elements within various embodiments of the present invention. Within this detailed description, the claimed invention will be explained with respect to preferred embodiments. However, a person having ordinary skill in the art will readily appreciate that the methods and systems described herein are merely exemplary and that variations can be made without departing from the spirit and scope of the invention.
Some aspects of the present invention are presented as a series of steps. Any particular order of steps is merely illustrative of one possible order. It should be understood that steps may be skipped, steps may be combined, steps may be divided, and the order of the steps may be varied without departing from the spirit and scope of the invention.
In some embodiments, the flush segments of the present invention facilitate fluid communication between many lumens of a multi-catheter system. The individual catheters of a multi-catheter system may be individually identified by at least four positional names, e.g. inner catheter, outer catheter, intermediate catheter, and adjacent catheter.
An inner catheter refers to a catheter that is nested inside at least one other catheter. In a preferred embodiment, the inner-most catheter of a multi-catheter system features a single fluid injection port. With the attachment of a single flushing device, the flush segments of the present invention enable simultaneous flushing of any number of catheters. Flush segments enable direct transluminal fluid communication between neighboring catheter lumens and indirect transluminal fluid communication between all other catheter lumens in a multi-catheter system of the present invention.
An outer catheter refers to the outermost catheter of a multi-catheter system. An outer catheter may include a sheath, a guide catheter, a reperfusion catheter, or the like. However, in some cases the outer catheter may be a flushing catheter. An outer catheter may receive direct or indirect fluid communication from an inner catheter, an adjacent catheter, or an intermediate catheter.
An intermediate catheter refers to a catheter inside of an outer catheter, e.g. the second largest catheter. In one example, an intermediate catheter is nested between an inner catheter and an outer catheter. Each catheter typically includes a male fastening mechanism, a female fastening mechanism, or both. These fastening mechanisms allow the catheters to be locked together in a sealed configuration while nested within one another. For instance, the intermediate catheter of this example will typically have a proximal female fastening mechanism attach to a smaller catheter and a distal male fastening mechanism attach to a larger catheter.
An adjacent catheter may refer to the next inner or next outer catheter in a multi-catheter system. In other words, “adjacent catheter” is context dependent and simply signifies a neighboring catheter in a multi-catheter system. An adjacent catheter may be a catheter that is nested between either two inner catheters, an inner catheter and an intermediate catheter, or an inner catheter and an outer catheter. Depending on context, an adjacent catheter may reference an outer catheter.
The first step of
The second step of
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The multi-catheter system 177 of
Referring now to detail 105 of
Detail 105 of
In some prior art designs, multi-lumen systems have an injection port for each individual lumen and annular lumen. These injection ports are usually angled (such as 45-degrees or 90-degrees) relative to the length of the multi-lumen system. These many ports encumber the proximal end of the device and add clutter and complexity. Additionally, the introduction of fluid requires an attachment step for each lumen on each injection port. Whether each injection port has its own injection device or simply a hose attached to a common injection device, the attachment of multiple components to a multi-lumen system causes clutter and encumbers the proximal end of such a system. In contrast, the flush segment(s) of the present invention enables multi-lumen access for flushing fluid with only a single attachment step to a single injection port. In a preferred embodiment, the single injection port is generally linear and aligned with a length of a flushing catheter. Additionally, the present invention enables a single step of fluid injection to flush every catheter of a multi-catheter system. Thus, the flush segment(s) and the single injection port facilitate a reduction in clutter, improves ease of use, and enables a less cumbersome multi-catheter system.
In order to flush a catheter or a multi-catheter system, the air within the system must be replaced with liquid. A catheter or multi-catheter system is flushed by injecting an “effective amount” of fluid. An effective amount can be determined through observation. In an observational approach, a user injects fluid until he or she observes fluid coming out the distal ends of all the catheters.
Flushing catheters that are nested together require less flushing fluid because there is less internal volume to be displaced. Thus, the present invention facilitates a reduction in the costs associated with flushing fluid and cuts down on unnecessary waste.
Separating or splitting a catheter or catheter component may be achieved with a blade (e.g. scissors, razorblade, etc.) or with concentrated radiative energy (e.g. laser, heat, etc.).
Once the catheter body 110 is separated from the catheter hub 109A, the catheter body 110 includes a proximal end 280, a proximal region 281, a central region 282, a distal region 283, and a distal end 284. The catheter body 110 may include one or more flush segments 102 along its length.
In any of the embodiments discussed herein, the devices may include one or more seals and/or membranes for creating a closed system. Seals and membranes allow inner catheters to pass through while also forming a seal between the inner surface of the outer device and the outer surface of the inner device to facilitate the formation of a closed system. Such seals are particularly beneficial in ensuring air does not enter devices after they have been purged of air with a fluid flush.
The flush segments 102 of a flushing catheter 100 are typically located in one or more regions among the length of the flushing catheter's catheter body 110. The flushing catheter 100 may be manufactured with one or more flush segments 102, may undergo post-processing to add one or more flush segments 102, or a flushing catheter 100 or a catheter 117 may be retrofit with a catheter subcomponent that includes one or more flush segments 102 (as will be discussed in greater detail in what follows).
Each flush segment of the present invention features one or more flush ports. The flush ports provide fluid communication between a catheter's lumen and a flush region that is external to the catheter. In general, the flush ports may vary from one another in geometry (e.g. size, shape, pattern) and orientation along the length of a flush segment. A group of flush ports that represent a repeated pattern may be referred to as a flush sector. Flush port variability may facilitate a variable volume of fluid transfer along the length of a flush segment and thus along a flushing catheter during flushing.
Flush ports may vary across the length of a flush segment and/or may vary from one flush segment to another. Likewise, a catheter body may include multiple copies of one or more flush segment varieties that alternate along the length of the catheter body. The flush port trends described here may vary along the length of a flush segment according to a trend that runs in a proximal to distal direction, a distal to proximal direction, a first end to second end direction, or a second end to first end direction. For instance, a flush segment may include round flush ports that increase in size along the length of the flush segment according to one of the aforementioned directions. Flush port and flush segment variations may be smooth, gradual, and uniform in direction or these variations may be quick to change, and such trends may even, at least temporarily, reverse in direction across a short group of flush ports in the given flush segment.
Flush ports may take on many different shapes and a flush segment's flush ports may change in shape from one end of the flush segment to the other. Each flush port may take on the shape of a circle, oval, ellipse, triangle, rectangle, five-or-more-sided polygon, convex polygon, star, teardrop, or the like. In one example, a flush segment's flush ports transition from a more rectangular shape to a more square shape along the length of the flush segment. In general, a flush port's shape may vary from its neighbors by one or more dimensions, including by height, width, radius, diameter, minor axis, and/or major axis. In another example, the flush port's shape on an outer surface is different than the same flush port on the inner surface, whereby the walls or thickness of the catheter body structurally supporting the flush segment act as a blend space between the two shapes (as depicted in
The orientation of a flush segment's flush ports may vary along the length of the flush segment and/or may vary between adjacent flush segments along the length of the entire catheter. Flush ports may vary in terms of spacing between adjacent flush ports. For instance, the spacing between flush ports may increase according to a trend along the length of a flush segment. Flush ports may be orientated into rows. The rows may be evenly spaced round the circumference of the given flush segment. The rows may be orientated parallel to or perpendicular to the longitudinal axis of the flush segment, or the rows may twist or tilt along such an axis. The rows may progressively vary along the length of the flush segment or may vary according to a pattern composed of multiple repeated flush sectors. In one case, the number of rows from flush segment to flush segment may increase or decrease to enable a variable volume of fluid transfer, i.e. flow rate. The phrase “flow rate” refers to a volume of fluid transfer per some increment time across a given flush port or flush segment. Flow rate refers to how much and how fast a flush port or flush segment provides fluid communication.
Variability among flush ports and flush segments may facilitate a variable flow rate along the length of the present invention. Flush port size, shape, and orientation may progressively change along the length of a flush segment to allow a greater flow rate in some regions and a lesser flow rate in other regions. A variable flow rate may progressively change along the length of a flush segment or the flow rate may follow a variable trend where flow rate increases and then decreases one or more times across the length of a flush segment. In one specific example, a flush segment has three rows of flush ports. Two rows have flush ports that increase in size in a proximal to distal direction, while the third row has flush ports that decrease in size in a proximal to distal direction, whereby the flush segment effects a variable flow rate along its length. In a further alternative, several flush segments effect a stepwise increase or decrease in flow rate along the length of a catheter.
Variability among flush ports and flush segments may facilitate a consistent flow rate along the length of the present invention. Flush port size, shape, and orientation may progressively change along the length of a flush segment to allow a consistent flow rate in one or more regions. For instance, the openings of the flush ports may grow in size slightly in a proximal to distal direction to enable a consistent flow rate for the length of the flush segment. This variability in size accounts for an injected fluid's loss of pressure head along the length of the flushing catheter. As fluid is introduced into a lumen of a catheter the pressure head is greatest near the injection site. As the fluid flows along the length of the catheter's lumen, the fluid's pressure head diminishes according to the friction of the lumen, the viscosity of the fluid, and the distance the fluid has traveled. Thus, two identical flush ports may enable different flow rates simply because one is further from the injection site than the other. Flush ports that increase in size or density in a proximal to distal direction may compensate for pressure head loss to enable a consistent flow rate across a group of flush ports.
Pressure head loss causes flush segments in a proximal region of a flushing catheter to provide a higher flow rate than identical flush segments located more distally. Additionally, fluid that flows through a flush segment in a proximal region must engage in a more limited degree of retrograde flow to fully remove air from an annular lumen as compared to flush segments located more distally. Thus, it may be preferable for a flushing catheter of the present invention to include a proximal region flush segment. A proximal region flush segment enables a higher flow rate and enables a more direct fluid path for removing air.
A flushing catheter according to the present invention may include one or more flush segments. Each flush segment includes one or more flush ports that may differ according to at least the variables described above. The flush ports enable fluid communication. Fluid communication typically refers to fluid that flows through a flush port from one side to the other. This fluid communication may flow from a lumen or annular lumen into a lumen, an annular lumen, a flush region, and/or an external space adjacent to a catheter. Fluid communication may also refer to intraluminal flow, transluminal flow 131, retrograde flow 132, and/or principal fluid 133 flow as described in reference to
In order to provide the desired type of fluid communication, the flush segment(s) may be located in one or more locations along the length of the flushing catheter. For instance, a flush segment in the proximal region of a flushing catheter may provide direct and immediate proximal or proximal-most fluid communication, and may provide central, distal, and/or distal-most fluid communication indirectly, e.g. through flow that disperses from the proximal region. A flush segment in the central region of a flushing catheter may provide direct and immediate central fluid communication, and may provide proximal-most, proximal, distal, and/or distal-most fluid communication indirectly, e.g. through flow that disperses from the central region. A flush segment in a distal region of the flushing catheter may provide direct and immediate distal or distal-most fluid communication, and may provide central, proximal, and/or proximal-most fluid communication indirectly, e.g. through flow that disperses from the distal region.
In general, the terms “distal-most” and “proximal-most” refer to a subsection within a distal region or proximal region, respectively. For instance, the distal-most region refers to a more distal portion of the distal region, and the proximal-most region refers to a more proximal portion of the proximal region. In regards to fluid communication, a distal-most fluid communication may refer to fluid that exits the distal end of a catheter or out of a flush segment in a more distal portion of the distal region, i.e. distal-most region. In contrast, distal fluid communication refers to fluid that exits a flush segment in the distal region of a catheter. The same holds true for proximal and proximal-most fluid communication.
In a further embodiment, the flushing catheter 100 includes a flush segment 102 that is longer than one or more regions of the catheter body 110. For instance, the flushing catheter 100 may include a flush segment along its entire length or may include a flush segment that stretches partially or completely over two or more regions. Flush segments of this type may provide partial fluid communication to some regions and complete fluid communication to other to other regions, or partial fluid communication to two or more regions.
A flushing catheter 100 may be constructed in several ways. In the examples above, the present invention included flushing catheters 100 with integrated flush ports 103. In the following examples, a flushing catheter is constructed from two or more subcomponents. In these examples, the present invention is embodied by a catheter subcomponent with at least one flush segment 102. These flushing retrofits (400, 500, 600) can be combined with catheters 117 and/or catheter parts to form a retrofitted flushing catheter (407, 507, 607). These retrofitted flushing catheters (407, 507, 607) provide at least the same fluid communication as the integrated flushing catheters described above. As used herein, “retrofit” may be used as a noun to refer to a flushing component that may be integrated into a catheter to form a flushing catheter. Additionally, “retrofit” may be used as a verb, e.g. to replace a catheter component and/or to attach a flushing subcomponent to other catheter subcomponents.
A flushing retrofit may be embodied in many ways. The flushing retrofit may include a full length of catheter body (e.g. flushing catheter body retrofit 400) or only a partial length of catheter body (e.g. flushing catheter extension retrofit 500). The flushing retrofit may include a catheter hub (e.g. flushing hub retrofit 600). Flushing retrofits may be attached to only a catheter hub, a hub and a catheter body, to only a catheter body, or to a catheter body on both sides. A flushing catheter typically requires a hub, so a flushing retrofit that does not include a hub is preferably attached to a hub or to a component that includes a hub.
In some of the examples that follow, the retrofits include a first end and a second end. The retrofit may be attached to a catheter or to catheter subcomponents on either the first end or the second end. The first end and the second end may correlate to a proximal region, a central region, or a distal region depending on the retrofit's orientation relative to the attached catheter or attached subcomponents. Proximal refers to the side of the catheter nearest the user, typically this is the side of the catheter with the hub, and distal refers to the side of the catheter furthest from the user, which is typically the end that is inserted into human vasculature during normal use.
In a multi-catheter system, a flushing retrofit may be partially covered by a neighbor catheter. For instance, the hub of a flushing retrofit will typically remain uncovered, but the proximal and central regions of the catheter body are typically covered by any neighbor catheters that are larger. The distal region may or may not be covered, depending on the relative length of the larger neighbor catheter(s). Flush segments may provide fluid communication to an external space outside of any catheter and/or an annular region within one or more other catheters, depending on their relative orientation to one another in the multi-catheter system.
In a first set of examples, the present invention is embodied by a full-length catheter body 110 that includes one or more flush segments 102, i.e. a flushing catheter body retrofit 400. These flushing catheter body retrofits 400 may be attached to a catheter hub or to a catheter body that includes a catheter hub. In either case, once the necessary catheter subcomponents are attached to the flushing catheter body retrofit 400, a flushing catheter 407 is created.
In another example, a flushing catheter body retrofit 400 may include a flush segment along its entire length or may include a flush segment that stretches partially or completely over two or more sides or regions.
In another set of examples, the present invention is embodied by a partial length catheter body that includes one or more flush segments, i.e. a flushing catheter extension retrofit 500. These flushing catheter extension retrofits 500 may be attached to a catheter hub and a catheter body, to only a catheter body, or to two catheter bodies. In any case, once the necessary catheter subcomponents are attached to the flushing catheter extension retrofit, a flushing catheter is created.
The separation step 502 introduced above may be executed in many different ways. A catheter 117 may be separated in a proximal region, a central region, or a distal region. The flushing catheter extension retrofit 500 may be attached wherever the separation is made. When the flushing catheter extension retrofit 500 is attached to a catheter 117 that was separated in the proximal region, then the retrofit may enable proximal fluid communication. When the flushing catheter extension retrofit 500 is attached to a catheter 117 that was separated in the central region, then the retrofit may enable central fluid communication. When the flushing catheter extension retrofit 500 is attached to a catheter 117 that was separated in the distal region, then the retrofit may enable distal fluid communication. In some instances, the flushing catheter extension retrofit 500 has a length sufficient to extend at least partially through two or more regions to provide a fluid communication across two or more regions. In an alternative construction, a catheter hub 141 and a catheter body 140 are simply provided in lieu of the separation step. Such components may have the same variable sizes as those produced by the variable separation steps detailed above. Thus, the present invention contemplates enabling proximal, central, distal fluid communication, and/or a combination of such fluid communications according to this alternative construction method as well.
In another set of examples, the present invention is embodied by a catheter hub with a partial length of catheter body, wherein the partial length of catheter body includes one or more flush segments, i.e. a flushing hub retrofit 600. These flushing hub retrofits may be attached to a catheter body. Such hubs typically include a proximal end 285 and a distal end (286B/286C). Once attached to the necessary catheter subcomponents, a flushing catheter 607 is created.
In one example, the catheter body 640 of the flushing hub retrofit 600 is entirely straight, maintaining an identical inner diameter and outer diameter from end to end. In a first illustrated example, the flushing hub retrofit 600 has a relatively linear catheter body 620. In alternative embodiments, the flushing hub retrofit's 600 catheter body may transition from a relatively large proximal diameter to a relatively small distal diameter. Such transitions in diameter may be smooth and gradual or the transition may occur over one or more steps. In a second illustrated example, the flushing hub retrofit 600 has a catheter body with a first taper 621A, that is relatively shallow, and then steps down to a second taper 621B, that is relatively steep. In a third illustrated example, the flushing hub retrofit 600 includes an angled catheter body 622, which is enlarged by detail 630. Angled catheter body 622 has an acute angle 632 relative to horizontal axis 631. When an angle for flushing hub retrofit's catheter body is referenced, it is understood to be the angle between a horizontal axis and the catheter body as depicted in detail 630. In some instances, a particular angle may beneficially provide a greater flow rate across the flush ports that have faces at the chosen acute angle. Alternatively, an angle may be chosen that reduces the flow rate. The angle may range between 1 degree and 45 degrees. In a fourth illustrated example, the flushing hub retrofit 600 includes a catheter body with a first angle 623A in a proximal region that is relatively shallow, then steps to second angle 623B in a central region that is relatively steep, and then steps again to a third angle 623C in a distal region that is relatively shallow. In one specific example, a flushing hub retrofit 600 has a first angle in the range of 5°-10°, a second angle in the range of 15°-25°, and a third angle in the range of 0°-5°. Of course, these angles are only exemplary and other angles consistent with the more general descriptions of these various embodiments are contemplated as within the scope of the present invention. For instance, in other embodiments, the outer diameter may oscillate one or more times between growing and shrinking in a proximal to distal direction according to a variety of favorable angles.
In any of the embodiments discussed herein, the flush ports may be at least semi-restrictive over certain types of fluid flow. Flow restriction may be achieved with a restriction means, such as valves, and pressure responsive slits. Such restriction means are capable of selectively restricting flow across individual flush ports. For instance, reverse Tuohy seals may manipulate the size of an individual flush port's opening. A pressure responsive slit may open and close under particular pressure differentials, such as when the pressure within the catheter is greater than the pressure outside of the catheter.
Flow restriction may also be achieved with covers for individual flush ports or covers for entire flush segments. Covers for individual flush ports may be embodied by flaps or hatches that are capable of selectively restricting fluid access to an individual flush port. For instance, a flap on the outer surface of a catheters flush port may open when fluid pressure inside is greater than outside pressure and may remain closed when fluid pressure inside is lower than outside pressure. Such a flap may be configured to enable one-way flow only. Covers for entire flush segments may be embodied by thin tubes, sheaths, or liners that are capable of selectively restricting access across a group of flush ports. An outer sheath or an inner liner with flush port sized holes may be axially translated and/or rotationally translated via a cord or wire mechanism controllable at the hub to move the sheath's or liner's holes at least partially out of alignment with the flushing catheter's flush port holes. In other embodiments, a structure within the walls of the flushing catheter may axially and/or rotationally translated (e.g. like a moonroof) to at least partially obstruct the flow of fluid through a set of flush ports.
In general, fluid flow may be restricted through an automated mechanism or through user control. Fluid flow may be automatically restricted with sensor controlled flush ports or by mechanical design. Fluid flow may be manually restricted with user controls such as slides, switches, and knobs. For instance, a slide may close two-way flush ports and one-way flush ports. A switch may restrict a two-way flush port to only allow fluid flow in one direction. A knob may be twisted to modulate or partially restrict fluid flow across one or more flush ports, whereby the degree the knob is twisted corresponds to the degree fluid flow is restricted. Such control features may be readily implemented by those with skill in the art.
In one embodiment of the present invention, two or more catheters are interlocked to form a multi-catheter system. The outer most catheter includes a flush segment 102 with flush ports 103 that are selectably restrictable by any of the methods described above. The inner catheters include at least one flush segment 102 and may or may not include a mechanism for selectably restricting flow across their flush ports. In such an embodiment, flushing may be restricted to certain catheter lumens and exclude others. Another option is to close at least a portion of the flush ports after the system has been purged of air with a fluid flush.
In one example, a flushing catheter includes at least one flush segment with selectably restrictable flush ports. When this example is used with an aspiration source, the flush ports may be opened and closed to manipulate the pressure within the flushing catheter.
In a second example of
Although
To reach a treatment site with a particular intravascular device, it is common practice to use several coaxial components in concert, such as access catheters, guide catheters, reperfusion catheters, microcatheters, guidewires, and other similar devices. Usually, a guidewire is the first device to fully navigate the vasculature and arrive at the treatment site. The guidewire then serves as a rail that guides other devices to the treatment site. However, as other devices track over the guidewire, they may unintentionally snag on branch vessels, which may cause vasculature damage and/or halt progression. This risk increases proportionally with the difference in diameter between the rail guide and the tracked device.
In one example, the present invention is embodied by method for modifying a catheter, wherein the method includes a step of selecting a catheter from an inventory of pre-fabricated catheters, said selected catheter comprising an elongate catheter body having a proximal region, a central region, a distal region, and a central lumen extending therethrough and a hub connected to the proximal region of the catheter body, said hub having a single injection port which provides a sole connection to a proximal end of the central lumen. Such a method may also include a step of forming flush ports in at least one of the proximal region, the central region, and the distal region, wherein the flush ports allow radial fluid flow through a wall of the elongate catheter body. Such a method may further include a step of introducing holes in an inner or outer sheath that match the holes made in the flushing catheter and affixing the sheath to the flushing catheter, wherein the sheath is configured to either axially translate, rotationally translate, or both.
In another example the present invention is embodied by a method for fabricating a flushing catheter, the steps including: (1) selecting a catheter hub or a catheter body; (2) selecting a flush retrofit from among a flushing catheter body retrofit, a flushing catheter extension retrofit, or a flushing hub retrofit; and (3) attaching the flush retrofit to the either the catheter hub, the catheter body, or both.
Any of the embodiments discussed herein may be constructed from one or more materials. For instance, the components may be constructed from a polymer such as: silicon, polyurethane, polyvinyl chloride, Nylons, or polyether block amides. Alternatively, the components may be constructed from an alloy such as: stainless steel, platinum, tungsten, and NiTinol. In some embodiments, the components may utilize a combination of different polymers and alloys. In some embodiments, some components of a given retrofit may be polymer based and other components may be alloy based. In one example, a retrofit is formed from hardened plastic with punch holes for flush ports. In another example, a retrofit is formed from an alloy based hypotube and the flush ports are cut into the hypotube.
In any of the embodiments discussed herein the retrofit may be fixedly attached by one or more methods. A catheter body, a hub, or both may be attached to a retrofit with an adhesive (e.g. UV glue), with a polymer jacket overmold, with a weld between the components, with heat induced melting, with a friction joint, with a fixed coupler, with a rotating connector, with a snap fit mechanism, with a clamp mechanism, or any combination of aforementioned methods. In some embodiments, a fastening mechanism may be first fixedly attached to a catheter body, a hub, or both, which then latches onto a structure of the given retrofit. Alternatively, the fastening mechanism is first attached to one or more sides of the retrofit before it is fitted onto other components.
While a number of preferred embodiments of the invention and variations thereof have been described in detail, other modifications and methods of using and medical applications for the same will be apparent to those of skill in the art. Accordingly, it should be understood that various applications, modifications, and substitutions may be made of equivalents without departing from the spirit of the invention or the scope of the claims.
While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.