Abstract:
The present invention relates to a catheter assembly including a catheter body, a first and a second set of a plurality of fenestrations, a first and a second inflatable device, a first and a second pleat, at least one obstructing stop near each end portion of the catheter body, and a first and a second flexible tube connected to the first and the second inflatable device. The catheter assembly further includes a pumping device in communication with the first and the second inflatable device via the first and the second flexible tube. The catheter assembly is used to restore blood flow to a traumatized blood vessel.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/728,433, entitled “Intravascular Shunt for Traumatized Arteries” and filed Nov. 20, 2012, the contents of which application are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to a catheter and a method of treating traumatized arteries using the catheter. 
       BACKGROUND OF THE INVENTION 
       [0003]    Hemorrhage remains a leading cause of death in trauma patients. Vascular injuries, which threaten both life and limb, have always constituted a serious problem in the surgical management of traumatic conditions. Intravascular shunts have been used to restore and maintain arterial flow during the repair of complex injuries, especially those involving extensive bony or soft tissue destruction. 
         [0004]    It is an object of the present invention, therefore, to provide a catheter assembly used as a shunt for restoring blood flow in a traumatized blood vessel. It is a further object of the present invention to provide a method for restoring blood flow to a traumatized blood vessel using a catheter assembly. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention relates to a catheter assembly for restoring blood flow to a traumatized blood vessel, comprising: a catheter body, in a tubular shape, comprising: a first and a second tip, each configured to permit insertion into a blood vessel without damaging an inner wall of a blood vessel lumen; a first and a second set of a plurality of fenestrations, disposed proximate to each tip extending a length of the catheter body away from each tip towards a center portion of the tubular catheter body; a first and a second inflatable device, placed circumferentially and longitudinally about the catheter body, configured such that when uninflated each is capable of sliding over a section of the catheter body, and when inflated an inner annulus of each presses against an outer perimeter of the catheter body; a first and a second pleat, spaced apart by a midsection, located in the center portion of the catheter body between the first and the second inflatable device; at least one obstructing stop, located on the outer perimeter of the catheter body in a section longitudinally adjacent to each of the first and the second set of the plurality of fenestrations towards the center portion, to obstruct the first or the second inflatable device from sliding over the first or second set of a plurality of fenestrations proximate to the first or the second tip of the catheter body, and a first and a second flexible tube connected to the first and the second inflatable device, respectively, and adapted to allow fluid communication from a pumping device with the first and the second inflatable device, wherein the first and the second pleats are capable of expanding on one side relative to another side to enable curving and bending of the catheter body in a vicinity of the first and the second pleats, and wherein the midsection is configured to receive an external clamp. 
         [0006]    In a preferred embodiment, the first and the second inflatable device each further comprises: a positioning and guiding member, attached to each of the first and the second inflatable device, for placing each of the first and the second inflatable device at a desired location by an operator. 
         [0007]    In another preferred embodiment, the positioning and guiding member comprises: an anchor portion proximate to the inner annulus of each of the first and the second inflatable device, capable of immobilizing an attached inflatable device on the catheter body; and a finger grip portion attached to the anchor portion for easy gripping. In another preferred embodiment, the anchor portion is ring-shaped disposed around the catheter body, and wherein the anchor portion and the finger grip portion are on a side of each of the first and the second inflatable device proximate to the first and the second pleat. 
         [0008]    In another preferred embodiment, the at least one obstructing stop comprises at least one of: 1) an adjustable stop, and 2) a fixed stop. In some embodiments, the adjustable stop comprises a groove selected from a plurality of grooves disposed longitudinally around the outer perimeter of the catheter body; and an elastic ring, wherein the groove and the elastic ring are configured such that when the elastic ring is installed in the groove, the elastic ring extends radially outward a sufficient distance to stop the inflatable device from sliding; and wherein the fix stop is affixed to the outer perimeter of the catheter body, and extends radially outward a sufficient distance to stop the inflatable device from sliding 
         [0009]    The present invention also relates to a system for restoring blood flow to a traumatized blood vessel, comprising: a catheter body, in a tubular shape, comprising: a first and a second tip, each configured to permit insertion into a blood vessel without damaging an inner wall of a blood vessel lumen; a first and a second set of a plurality of fenestrations, disposed proximate to each tip extending a length of the catheter body away from each tip towards a center portion of the tubular catheter body; a first and a second inflatable device, placed circumferentially and longitudinally about the catheter body, configured such that when uninflated each is capable of sliding over a section of the catheter body, and when inflated an inner annulus of each presses against an outer perimeter of the catheter body; a first and a second pleat, spaced apart by a midsection, located in the center portion of the catheter body between the first and the second inflatable device; at least one obstructing stop, located on the outer perimeter of the catheter body in a section longitudinally adjacent to each of the first and the second set of the plurality of fenestrations towards the center portion, to obstruct the first or the second inflatable device from sliding over the first or second set of a plurality of fenestrations proximate to the first or the second tip of the catheter body; a pumping device; a first and a second flexible tube connecting the pumping device with the first and the second inflatable device, respectively, wherein the first and the second pleats are capable of expanding on one side relative to another side to enable curving and bending of the catheter body in a vicinity of the first and the second pleats, wherein the midsection is configured to receive an external clamp, and wherein the pumping device is in fluid communication with the first and the second inflatable device via the first and the second flexible tube, respectively. 
         [0010]    The present invention further provides a method for restoring blood flow to a traumatized blood vessel using the catheter assembly of the current invention, comprising the steps of: a) inserting a first tip of a catheter body into a lumen of a first undamaged portion of the traumatized blood vessel so that a first set of a plurality of fenestrations, disposed proximate to the first tip, are inside the first undamaged portion of the traumatized blood vessel; b) positioning a first inflatable device along a first length of the catheter body to a first location proximate to the first undamaged portion of the traumatized blood vessel; c) inserting a second tip of the catheter body into the lumen of a second undamaged portion of the traumatized blood vessel so that a second set of a plurality of fenestrations, disposed proximate to the second tip, are inside the second undamaged portion of the traumatized blood vessel, by bending the catheter body using at least one of a first and a second pleat so that the catheter body conforms to a contour of an injured area, wherein the second undamaged portion of the traumatized blood vessel is separated from the first undamaged portion of the traumatized blood vessel by a damaged portion of the traumatized blood vessel; and d) positioning a second inflatable device along a second length of the catheter body to a second location proximate to the second undamaged portion of the traumatized blood vessel. 
         [0011]    In one embodiment, the first and the second inflatable device are uninflated, and the method further comprises a subsequent step of inflating the first and the second inflatable devices with a pumping device. 
         [0012]    In another embodiment, the method further comprises a step of holding the catheter body in place by clamping around the midsection. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    For the purpose of illustration, there is shown in the drawing certain embodiments of the present invention. In the drawing, like numerals indicate like elements throughout. It should be understood that the invention is not limited to the precise arrangements, dimensions, and instruments shown. In the drawing: 
           [0014]      FIG. 1  is a schematic representation of a system for restoring blood flow to a traumatized blood vessel according to one embodiment of the present invention; 
           [0015]      FIG. 2  is a schematic representation of a catheter assembly according to one embodiment of the present invention; 
           [0016]      FIG. 3  is a schematic representation of a catheter assembly according to another embodiment of the present invention; 
           [0017]      FIG. 4  is a schematic representation of a catheter assembly according to another embodiment of the present invention; and 
           [0018]      FIG. 5  is a schematic representation of a system for restoring blood flow to a traumatized blood vessel according to one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    Reference to the drawing illustrating various views of exemplary embodiments of the present invention is now made. In the drawing and the description of the drawing herein, certain terminology is used for convenience only and is not to be taken as limiting the embodiments of the present invention. 
         [0020]      FIG. 1  is a schematic representation of a catheter assembly used to restore blood flow to a traumatized blood vessel. Some embodiments of the present invention are used in cases in which the trauma to the body includes an open wound that permits endovascular access to the damaged artery. In other cases, the wall of the artery is damaged, but the arterial tissue both upstream and downstream of the damage is generally intact. 
         [0021]    The catheter assembly  20  includes a catheter body  30 , generally in a tubular shape, preferably having a pair of inflatable devices such as balloons that can be easily slid along the length of the catheter. A pumping device  22 , such as a hand pump, provides a mechanism for pressurizing the balloons after they have been located in their proper positions. The catheter assembly  20  includes a catheter body  30 , preferably fabricated from a flexible material, and adapted and configured to fit within a blood vessel of a patient. 
         [0022]    Each end of the catheter  30  includes a tip  38  that is configured to permit the end of the catheter to be inserted into a blood vessel without damaging the inner walls of the vessel lumen as the catheter tip  38  is inserted into the vessel. The tips  38  are shown in the shape of a truncated cone, but can be of any shape (such as rounded) to minimize friction or interference with the lumen inner wall. Although the tips  38  are shown on the ends of the catheter  30  with a generally straight, coaxial shape, other embodiments may be utilized. In some embodiments, one or more of the tips  38  are offset to one side so as to permit the user to twist the catheter body  30  within the vessel and preferably guide it to a branch vessel. In yet other embodiments, one or more of the ends of the catheter  30  are curved to facilitate the guidance of the tip  38  into a branching vessel. Further, although the tips  38  are shown as generally closed, other tips may have one or more openings or fenestrations to permit the flow of fluid. In yet other embodiments, the tips  38  are fabricated from a mesh material. 
         [0023]    Located proximate to each tip  38  is one or more fenestrations  36  to provide fluid flow (such as blood) in and out of the interior of the catheter  30 . The one or more fenestrations  36  extend along a length of the catheter body  30  in a direction from the tip toward the center of the catheter. 
         [0024]    Located inwardly from the fenestrations  36  are one or more obstructing stops. These stops prevent the balloons  28   a  and  28   b  from sliding over the fenestrated portions of the catheter  30 .  FIG. 1  shows a fixed stop  40  located on the left side of catheter  30 . The fixed stop  40  is affixed to the outer perimeter of the catheter body  30 , and extends radially outward a sufficient distance so as to interfere with the movement of the balloon  28   a  and to stop the balloon  28   a  from sliding past the fixed stop  40 . In some embodiments, the fixed stops  40  are circular rings extending around the circumference of the catheter body  30 . In yet other embodiments, the stops  40  can be a single outwardly-extending projection, a pair of projections, or the like. 
         [0025]    Other embodiments of the present invention include one or more adjustable stops located inward from the fenestrated ends of the catheter body  30 . As seen on the left side of  FIG. 1 , a ring  44  (such as an o-ring or other elastic ring) is shown located within a groove  42  that extends around the circumference of the catheter body  30 . An adjustable stop is formed by the placement of an elastic ring  44  within a groove  42 . It can be seen that some embodiments include multiple circumferential grooves  42  among which one is selected to place the ring  44 , thereby allowing adjustment of the length of the section of the catheter body  30  on which the uninflated balloon  28   a  slides. The rings  44  and grooves  42  are adapted and configured such that the outer diameter of the ring  44  when installed in a groove extends radially outward a distance sufficient to interfere with the sliding movement of the balloons  28   a  and  28   b.    
         [0026]    The catheter body  30  includes a pair of pleated areas  32   a  and  32   b  that are preferably spaced apart by a midsection  34 . The pleats  32   a  and  32   b  are capable of expanding on one side relative to another side (such as from top to bottom) such that the overall shape of the catheter  30  can be curved or bent in the vicinity of the pleats. The pleats  32   a  and  32   b  preferably hold their positions after the catheter is reshaped to the new configuration. In that manner, the catheter body  30  can have a curved shape or an S shape. By using the pleats  32   a  and  32   b  in that manner, the overall shape of the catheter body  30  can be adapted to better fit the shape of the traumatized anatomy. And, by better accommodating the traumatized anatomy, the catheter body  30  is more likely to stay in place if the injured patient moves. 
         [0027]    In yet other embodiments the pleats  32   a  and  32   b  are adapted and configured to serve as finger grips for the emergency technician. In such embodiments it is recognized that the smooth outer diameter of the catheter body  30  may be inadequate for sufficient grip in stressful situations (such as in warfare). In some embodiments, the tips of the pleats  32 , as well as their larger diameter, provide improved grip of the catheter body  30  as well as a tactile sense of where the technician&#39;s fingers are located along the length of the catheter body  30 . In other embodiments, the pleats are replaced with a series of non-expandable ridges or other tactile features. 
         [0028]    Preferably located between the pleated areas  32   a  and  32   b , is a mid-section  34 , adapted and configured to receive an external clamp. In some embodiments, the midsection  34  has a cylindrical outer shape. In yet other embodiments, the mid-section  34  is fabricated with thicker walls for increased strength in compression. In still other embodiments, the mid-section  34  can include one or more outward projecting features that are adapted and configured to receive therebetween the ends of a clamp. In some embodiments that don&#39;t include pleats, a mid-section  34  that is adapted and configured for clamping can be established by a pair of spaced-apart rings or projections. In that manner, an external clamp can be coupled to the mid-section  34  and also be coupled to the clothing or anatomy of the patient. That external clamp helps maintain the catheter body  30  in a fixed position on the injured patient, especially for those situations in which the patient is being moved and subjected to external disturbances (such as a bumpy road, or handling on a stretcher). 
         [0029]    The catheter body  30  is received within the inner circumferences of a pair of balloons  28   a  and  28   b . Preferably, each of the balloons  28   a  and  28   b  is generally slidable along the length of the external surface of the catheter body  30 . However, in some embodiments, one of balloons  28   a  and  28   b  may be fixed to the outer diameter of the catheter body  30  at a specific location. The balloon  28   a  is located between the pleats  32   a  and the fixed stop  40 . The balloon  28   b  is located between the pleats  32   b  and the tip  38 . The balloon  28   b  could be removed from the catheter body  30 , whereas the balloon  28   a  is captured within a portion of the length of the catheter body  30 . In their uninflated states, the balloons  28   a  and  28   b  slide easily over their respective portions of the catheter body  30 . 
         [0030]    In some embodiments, each of the balloons  28   a  and  28   b  includes a positioning and guiding member  29  attached to the balloon, and in some cases, integrally molded with the balloon. That positioning and guiding member  29  has sufficient rigidity to be used by the emergency technician for placing a balloon  28   a  or  28   b  at the desired location. It is recognized that in some situations the trauma is such that the positioning of balloon  28   a  or  28   b  may be a blind positioning, in which case the positioning and guiding members  29  are used to assist in positioning the balloon, even though the balloon cannot be seen. 
         [0031]    In some embodiments, the positioning and guiding member  29  includes an anchor portion  29 . 1  (e.g. cylindrical or ring-shaped) that is coupled to a balloon  28   a  or  28   b  proximate to the inner periphery (or annulus) of the balloon. Preferably, the anchor portion  29 . 1  has a ring shape of sufficient rigidity so as to uniformly impart the sliding load applied by the emergency technician into the balloon. Located at the inner ends of the anchor portion  29 . 1  proximate to the pleats is a flexible finger grip  29 . 2 , adapted and configured to be easily pinched by the fingers of the technician, and further to impart the load from the physician&#39;s finger into the anchor portion  29 . 1 . The technician uses the finger grip  29 . 2  to move the balloons along the length of the catheter body  30 . As shown with the left side balloon  28   a , the finger grip  29 . 2  is sufficiently flexible (shown in the Figure as being deflected by the pleats  32   a ) so as to not interfere with the operation of the catheter assembly  20 , yet rigid enough to withstand a compressive load applied by the technician without buckling. The cross sectional shape of the finger grip  29 . 2  may be circular (corresponding to a rod-like projection) or a sector of a circle (such as a thin plate coupled to a circumferential sector of the guiding feature  29 . 1 ), as examples. 
         [0032]    The balloons  28   a  and  28   b  can be inflated with a gas or a liquid (such as saline) and each is connected by a flexible tube  26  that provides fluid communication with a source of pressure, such as a pumping device  22 . Pressure (such as air pressure) can be applied by the pumping device  22  through conduits, such as the flexible tube  26 , so as to inflate the balloons  28   a  and  28   b . In one embodiment, the pumping device is adapted with ports for the conduits and an infusion device. In another embodiment, one of the ports allows deployment of the device over a wire. 
         [0033]    When inflated, the balloons  28   a  and  28   b  tighten their inner annulus against the outer perimeter of the catheter body  30  so as to form a generally leakproof seal. In their inflated state, the balloons  28   a  and  28   b  are maintained at a fixed position on the catheter body  30  by friction. It is understood that in some embodiments, either the inner surface of the balloons  28  and/or the outer perimeter of the catheter body  30  can be treated to have increased friction. Examples of such treatment include coatings (such as the coatings used to form tamper-evident regions on flexible recloseable containers). Yet another example of such treatments is physical impressions or projections, such as a cross-hatch pattern, a pattern of rings, a pattern of sawtooth teeth, or others. 
         [0034]    In some embodiments, the source of pressure is a pumping device  22  adapted and configured to be operated by a single hand of an emergency technician. As the technician grabs the pumping device  22  and squeezes it, air pressure is provided by conduits, such as the flexible tube  26 , into the balloons  28   a  and  28   b , thereby causing them to expand. Preferably, both of the flexible tubes  26  are attached to a single source of pressure (the pumping device  22 ), which minimizes the amount of equipment that an emergency technician must cope with while treating the injured patient. In some embodiments, the pressure source includes a relief valve  24  that releases pressure in the balloons  28   a  and  28   b  so as to prevent overexpansion, distortion or rupture of the balloons. 
         [0035]    During use, the emergency technician locates the bleeding artery in the patient&#39;s wound. The technician then advances the first tip of the catheter body within the damaged artery  41  until a first balloon  28   a  is located proximate to a first undamaged portion of the traumatized artery  42 , as shown in  FIG. 4 . In some embodiments, the pumping device  22  includes a switch or valve that permits the technician to expand the first balloon during this phase of partial insertion. In yet other embodiments, both balloons are expanded simultaneously. 
         [0036]    After the first end of the catheter body  30  is inserted within the artery and the first balloon  28   a  (whether inflated or deflated) is positioned proximate to the undamaged tissue with the aid of the finger grip  29 . 2 , the position of the first balloon  28   a  is immobilized by the anchor portion  29 . 1 . The technician then places the second tip of catheter body  30  into the lumen of the damaged artery. By handling the finger grip  29 . 2 , the technician positions the second balloon  28   b  along the length of the catheter body  30  to a location that is proximate to a second undamaged portion of the traumatized artery. The second balloon  28   b  is immobilized in a like manner as the first balloon  28   a  using the anchor portion  29 . 1 . The second balloon  28   b  is inflated with pumping source  22  (or alternatively, both balloons are inflated at this time). As the second end of the catheter is inserted into the lumen of the damaged artery, the technician bends or curves the catheter body  30  by way of the pleats  32  so as to best accommodate the shape of the injury and the location of the damaged artery. As the catheter body  30  is being situated within the damaged artery, the technician can use a clamp (not shown) around the midsection  34  to securely hold the catheter body  30  in place. This clamp can then be coupled (such as by tape) to the anatomy of the patient. 
         [0037]    While the inventions have been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only certain embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. 
         [0038]    These and other advantages of the present invention will be apparent to those skilled in the art from the foregoing specification. Accordingly, it is to be recognized by those skilled in the art that changes or modifications may be made to the above-described embodiments without departing from the broad inventive concepts of the invention. It is to be understood that this invention is not limited to the particular embodiments described herein, but is intended to include all changes and modifications that are within the scope and spirit of the invention.