Abstract:
A corporeal catheter comprising a catheter tube having a distal end to which a bolus is connected. The bolus contains a tip section and a tube connector section between which a bolus passage section is disposed. The bolus passage section has a passage therein which communicates through a radial port area with the outside of the generally tubular shaped bolus. The port area includes a port mouth which is elongated between opposed elliptical curved surfaces defining a concave arch. Opposite the concave arch port mouth, under the port is a convex stiffening arch on the bolus and axially aligned with it.

Description:
RELATED APPLICATIONS 
       [0001]    This application is based upon Provisional Application Ser. No. 61/654,448 filed on Jun. 1, 2012, and claims priority therefrom. Provisional Application Ser. No. 61/654,448 is incorporated herein by reference, in its entirety. 
     
    
     FIELD OF INVENTION 
       [0002]    The invention relates to corporeal catheters for use in administering fluids to body cavities, especially the stomach or intestine, or irrigating the cavities and aspirating the cavities. It relates particularly to catheters having distal ends that contain opening(s) or ports for fluid egress or ingress. Applications for these catheters also include wound drainage and the use of endotracheal tubes for pulmonary usage. The basic invention may also relate to intravenous catheters utilized for the instillation or evacuation of fluids in the circulatory system. It may also relate to urology catheters for accessing the bladder. 
       BACKGROUND OF THE INVENTION 
       [0003]    Catheters are commonly used for enteral feeding, urinary bladder drainage and irrigation, suctioning of blood and mucosa, and for other purposes in the medical treatment of humans. Exemplary catheters are illustrated and described in U.S. Pat. Nos. 4,594,074, No. 4,410,320, No. 4,390,017, No. 4,388,076, No. 4,220,542, No. 5,451,216 and No. 5,810,787. Each of these catheters employs a tube with a bolus at its distal end and an opening or port extending either axially from the tube end bolus or from its side. 
         [0004]    In the catheters illustrated in U.S. Pat. No. 5,451,216 and U.S. Pat. No. 5,810,787, the ability to aspirate is enhanced by the use of an enlarged size of the opening or port. This size increase is achieved in the &#39; 787  patent catheter by extending the port opening to upstanding side-walls of the bolus. The enlarged port effectively encloses at least 180 degrees of the inside circumference of the passage in the bolus. This bolus passage also incorporates a floor of the passage that curves upwardly in an arc of substantial radius extending axially of the catheter tube and bolus. These bolus designs approximate the fluid flow characteristics of an open-ended tube, and fluid flow out of the port is achieved at a rate of approximately 100% of the tube outflow rate. Clinical studies show, that in both of these designs, aspiration can be achieved in 85% of attempts versus only 15% in earlier other designs. 
         [0005]    It is recognized that 100% aspiration could be achieved by increasing the size of the bolus by either lengthening it or by decreasing the height of the substantially vertical side-wall portions bracketing the port to a level beyond 180 degrees. However, making such changes to the port result in weakening the bolus, with resultant kinking and occlusion of the bolus at the port. The hereinafter described catheter invention of the present application increases the overall effective size of a bolus port by 41% over that described in the &#39;787 patent and achieves an aspiration rate of 100% while preventing any bolus kinking. 
       SUMMARY OF INVENTION 
       [0006]    A primary object of the present invention is to provide a corporeal catheter including an improved bolus for a catheter tube. 
         [0007]    Another object is to provide a new and improved enteral, single lumen feeding tip that greatly reduces clogging. 
         [0008]    Yet another object is to provide a new, enteral single lumen feeding tip bolus that increases the ability to aspirate gastric or jejunal contents at a rate of up to as much as 100% of the catheter tube flow rate. 
         [0009]    A further object is to provide a bolus having a radial port size increase from 189 degrees of the total 360 degrees of the bolus tip outside diameter to 206 degrees of this outside diameter. 
         [0010]    Another object is to provide a bolus having a port whose depth is increased from previous catheter bolus depth of slightly below the catheter tube lumen midpoint or radius to a depth that is slightly below 75% of the tube bolus lumen inside diameter. 
         [0011]    Another object is to provide a bolus port that never produces restrictions of any kind that are less than the internal cross-sectional area of the catheter tube lumen. 
         [0012]    Still another object of the invention is to provide a single lumen bolus tip having the lowest possible port sides, of height and resultant largest cross-section of the bolus port passage while, at the same time, creating a bolus tip that does not bend. 
         [0013]    Yet another object of the present invention is embodied in a catheter bolus port which is effectively enlarged in its length without increasing the actual length of the bolus. 
         [0014]    Still another object is to provide a catheter bolus which has an overall shape that reduces, and minimizes, both patient pain and mucosal damage during insertion, retention and tube removal. 
         [0015]    The foregoing and other objects of the invention are embodied in an improved catheter including a bolus with an enlarged and improved port for delivering fluid to a body cavity or aspirating the cavity. The bolus includes a tubular shaped body formed of semi-rigid plastic. The body of the bolus contains a tube connection section at one end, a tip section at the other end and passage section between the connector section and the tip section. The passage section also contains a symmetrical radial passage portion adjacent the tip section that foams a port through the side of the body. This passage portion contains two identical elliptical surface portions that connect the top-most section of the symmetrical radial passage to the tube connector section and the tip section. This passage section also contains a curving floor that curves upwardly to form a flow direction passage that terminates at the midpoint of a port defining concave arch. The passage section further includes a bolus body section opposite the port. The body section connects the tip section with the connector section. Side walls are formed only in the bottom one-half of the passage section that is under the one-half of a concave radial arch that connects to the connector section. The passage, at its lowest point, has a height that is slightly lower than 75% of the inside diameter of the tube lumen, or 206 degrees. The body segment also includes a structural component protruding radially outwardly therefrom, and is effective to prevent the body segment from bending and restricting the port. This structural component is also symmetrical about its midpoint, directly aligned perpendically with the midpoint of the symmetrical radial passage forming the port opening through the side of the body, thereby further preventing kinking, bending and resultant flow restriction by acting with each other to distribute forces which effectively produce reinforcement of the bolus. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    The invention, including its construction and method of operation, is illustrated more or less diagrammatically in the drawings, in which: 
           [0017]      FIG. 1  is a side view showing the catheter bolus connected to the catheter tube, and showing the bolus port shape; 
           [0018]      FIG. 2  is a top plan view of the bolus end of the catheter seen in  FIG. 1 , showing the port and identifying the portion of the port that is recessed behind the vertical side walls of the bolus tube connector; 
           [0019]      FIG. 3  is a front end view of the catheter bolus, bullet tip as seen in  FIG. 1 ; 
           [0020]      FIG. 4  is a perspective view of the catheter seen in  FIG. 1 , and again shows the portion of the bolus port that is recessed behind the aforementioned vertical port walls, the recessed portion of the port comprising 50% of the length of the port (note the remaining 50% of the port having no side walls); 
           [0021]      FIG. 5  is side elevational view of the bolus shown in  FIG. 1  showing cross section lines for  FIGS. 6-13  which follow; 
           [0022]      FIG. 6  is a sectional view taken along line  6 - 6  of  FIG. 5  showing the cross-section of the catheter; 
           [0023]      FIG. 7  is a sectional view taken along line  7 - 7  of  FIG. 5  showing the tube and bolus connecting portion of the bolus; 
           [0024]      FIG. 8  is a sectional view taken along line  8 - 8  of  FIG. 5  showing the proximal initial portion of the bolus port; 
           [0025]      FIG. 9  is a sectional view taken along line  9 - 9  of  FIG. 5  showing the midpoint of the bolus portion that has substantially vertical side-walls; 
           [0026]      FIG. 10  is a sectional view taken along line  10 - 10  of  FIG. 5  showing the lowest point of the port where the port transitions from a port with side-walls; 
           [0027]      FIG. 11  is a sectional view taken along line  11 - 11  of  FIG. 5  showing the shape of the bolus as it ascends; 
           [0028]      FIG. 12  is a sectional view taken along line  12 - 12  of  FIG. 5  showing the continuation of the ascent of the port without side-walls at the point where the ellipse that forms the top distal end of the port, and the bullet tip begins; 
           [0029]      FIG. 13  is a sectional view taken along line  13 - 13  of  FIG. 5  at the midpoint of the bullet tip; 
           [0030]      FIG. 14  is a longitudinal sectional views showing the tube/tip connection and the sloping floor of the port where this sloping floor meets the mid point of the port and where the side walls end and the end of the tube; 
           [0031]      FIG. 15  is a side elevational view of the catheter bolus shown in  FIG. 1  and, also, showing the separated bottom arch and the smaller upper arch on the same vertical perpendicular axis that forms the bolus bottom and the main bolus port, as well as the two identical smaller ellipses and the segments that form the top proximal and distal ends of the bolus port shown in  FIG. 1 ; 
           [0032]      FIG. 16  is a sectional view taken along line  14 - 14  of  FIG. 5  also showing a phantom cross-section of the vertical side of the bolus including its cross-section in square inches; 
           [0033]      FIG. 17  is a cross-section similar to  FIG. 16 , but of the bolus in Quinn U.S. Pat. No. 5,810,787, the phantom cross-section with its size is shown as it is in  FIG. 16 ; 
           [0034]      FIG. 18  is a cross-section similar to  FIG. 10  showing the lowest point of the bolus port at 206 degrees of the OD of the bolus and the radial axis of the tube lumen; 
           [0035]      FIG. 19  is a cross section of the bolus of the tip covered by U.S. Pat. No. 5,810,787 where the lowest point of the bolus is slightly below the radius of the bolus covering 186 degrees of the bolus; 
           [0036]      FIG. 20  is a cross-section of the bolus covered by Quinn expired patent U.S. Pat. No. 4,594,074 where the vertical port side-walls are lowered to the level of the top of the internal lumen of the bolus; 
           [0037]      FIG. 21  is a cross-section of a conventional punched side hole port in a bolus or a tube; 
           [0038]      FIG. 22  is a perspective view of the bolus port&#39;s “phantom” shape showing its “wrapped around” configuration; 
           [0039]      FIG. 23  is a “flattened” version of the shape shown in  FIG. 22 ; this version showing the actual cross-sectional area of the bolus of the invention as it surrounds 206 degrees of the bolus; 
           [0040]      FIG. 24  is a “flattened” version of the port size of U.S. Pat. No. 5,810,787 that surround 186 degrees of the bolus (it is approximately 29% smaller than the port shown in  FIG. 23 ); 
           [0041]      FIG. 25  is a flattened version of the port size illustration of U.S. Pat. No. 4,594,074 that covers only 115 degrees of the bolus port, a cross-sectional area that is less than half of that of the bolus port in the present invention; 
           [0042]      FIG. 26  is a flattened version of a conventional side hole port. 
           [0043]      FIG. 27  is a side elevational view of the catheter of  FIG. 1  showing the relation of an adjacent jejunum wall; 
           [0044]      FIG. 28  is a side elevational view of another version of the invention wherein the bolus is formed on the actual tube by “over-molding” to the tube, and the tube is skived to form approximately 50% of the actual port (over-molding generally is described in Quinn U.S. Pat. No. 7,988,658); 
           [0045]      FIG. 29  is a sectional view of  FIG. 28  and shows the formation of the bolus with the floor of the port passage curving to meet the midpoint of the port, the bottom convex arch forming the bottom of the bolus and the top smaller concave arch forming the vertical side-walls of the port are aligned again on same perpendicular axis; 
           [0046]      FIG. 30  is a sectional view of  FIG. 28  showing the skived tube. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0047]    Preferred embodiments of the invention are described here in the context of a catheter for use in enteral feeding. However, features of the invention may apply equally well to all types of catheters, including Foley catheters, urethral catheters and catheters for use in such diverse applications as intravenous, pharyngeal, esophageal, recta-colonic, gastric, nasal, wound drainage and endo-bronchial procedures, as well as others. 
         [0048]    Referring now to the drawings, and particularly to  FIG. 1 , a catheter  10  comprising a catheter tube  11  (partially shown) and a bolus tip  12  is illustrated in side elevation. The catheter tube  11  is fabricated from a resilient, biocompatible, thermoplastic material such polyurethane. Although other plastics, including polyvinylchloride, may be used, the properties of polyurethane are such that it can be fabricated with maximum inside tube lumen diameter and minimum tube wall thickness. It also has a high resistance to highly acidic fluids frequently encountered in clinical applications. Thermo-set materials such as silicone may also be used, however. 
         [0049]    The tube  11  used as an example is shown as a 9FR (FRENCH) tube, which has an OD (outside diameter) of 0.124 inches. The tube lumen  13  has an cylindrical ID (inside diameter) of 0.090 inches. Common FR sizes for this type of catheter tube  13  run from the smallest 3FR to tubes as large as 30FR. The bolus  12  is also fabricated from polyurethane with a hardness in the range of 80A. 
         [0050]    Still referring to  FIG. 1 , the bolus  12  has an external concave arch (arcuate external protuberance)  32  extending from the tube  11  at proximal point  34  to a distal point  30  where it meets elliptical profile bullet bolus tip  40 . This arch  32  extends outwardly and longitudinally of the tube  11  axis and has a radius of 1.903 inches (axially extending). At its midpoint the arch  32  extends downwardly (radially) 0.015 inches to its deepest point from the OD of the bolus tube gluing section  14 . Both ends of the bolus  12  terminate at the same longitudinal level, that is, the OD of the bolus gluing section  14 . This external arch  32  is important because it provides stiffness to the bolus  12  through the bolus port area  22  above. The arch  32 , as shown, has a length of 0.480 inches (axially). 
         [0051]    The bolus inflow/outflow port  15  is defined opposite the external reinforcing convex arch  32  by an inwardly extending structural concave arch  23  that begins at point  20  where it connects with ascending small ellipse  18  and forms the port area  22 . Arch  23  descends from point  20  and then ascends to point  24 . Point  24  is the beginning of ellipse  28  that forms the bolus bullet tip. Point  25  is the midpoint of the inner concave arch  23 . Arch  23  has a radius of 0.179 inches. 
         [0052]    Arches  23  and  32  both have their midpoint on the same imaginary line that is perpendicular to the longitudinal internal axis  44  of tube  11 . This relationship is shown graphically in  FIG. 15 . The alignment of the two arches radii in relation to each other is very important to providing a bolus that can flex against a body cavity or mucosa, while at the same time not kinking. The convex long arch  32  provides anti-kinking protection over the full length of the upper bolus area defined by the radius of the concave upper arch  23 . This lower bolus arch  32  must be stretched when kinking pressures are applied. 
         [0053]    Now referring to both  FIG. 1  and  FIG. 14 , the floor of the tube  11  lumen begins to rise and form a 0.524 inch radius  46  at the point  20  where the bolus port  15  becomes fully open. This radius  46  terminates at the midpoint  25  of upper arch  23 . This connection between floor radius  46  and radius of the arch  23  is critical to the strengthening of arch  23 . The distal one-half of arch  23  is now solid plastic. The proximal one-half of the arch  23  is trapped by solid top  40  point and the open edge of ellipse  18 . Because radii  23  and  32  are aligned with each other, they provide maximum rigidness while, at the same time, providing resistance against kinking. 
         [0054]    Now referring to  FIG. 1  and  FIG. 15  the top open portion of the port  15  is formed by ellipses  18  and distal ellipse  28 . Distal ellipses  28  forms the leading edge of ellipse  28  that also extends to form the bullet tip. Both ellipses dimensions are X 0.107 inches and Y 0.077 inches. These ellipses connect to the main radius of the arch concave upper  23  tangentially and serve two purposes. First, they provide an effectively larger recessed port  15  than if they were radii. Second they provide a smoother transition to the bolus OD thereby providing a tissue-friendly transition during tube placement, tube removal and when in-situ in a vessel of body cavity. The proximal ellipse  18  transitions from 16 to 20 and the distal ellipse transitions from point  24  to  26 . As shown graphically in  FIG. 15  both ellipses have their axis from center radius  44  of the tube  11 . 
         [0055]      FIGS. 16  shows the vertical port cross-section phantom as defined by concave arch  23 , ellipse  18  and ellipse  28  of the invention. Also shown are phantom tube lumens  13  exiting unrestricted through port  15 . 
         [0056]      FIG. 17  shows the vertical cross section of the bolus described in Quinn U.S. Pat. No. 5,810,787. The present bolus invention  12  has a 41% larger vertical cross sectional area than the bolus in Quinn US Pat. No.  5 , 810 , 787 . 
         [0057]      FIG. 18  shows the cross-section, radial arc of the invention. This radial shape covers 206 degrees of the port OD. This arc extends slightly more than two thirds of the internal lumen OD of the tube  11 . 
         [0058]      FIG. 19  shows the cross-sectional radial arc of Quinn U.S. Pat. No. 5,810,787 that extends 0.186 degrees around the bolus, or slightly below the midpoint or radius of the tube lumen. 
         [0059]      FIG. 20  shows the port of expired (Quinn) U.S. Pat. No. 4,594.074 that extends to the OD of the tube&#39;s internal OD and forms a port extending 106 degrees around the bolus. 
         [0060]      FIG. 21  shows a cross section of a conventional, punched side hole port that has a small cross sectional area and is easily occluded during aspiration. 
         [0061]      FIG. 22  illustrates in phantom form the actual shape of the port area  22  of in the bolus invention.  FIG. 23  shows the actual effective cross-sectional area of the invention bolus port area  22  in a “flattened” form. 
         [0062]      FIG. 24  shows the effective flattened area of Quinn U.S. Pat. No. 5,810,787  FIG. 25  shows the effective flattened area of Quinn U.S. Pat. No. 4,594,674 and 
         [0063]      FIG. 26  the punched side hole. Extending the depth of the vertical side of the ports and extending the longitudinal shape of the port increases the overall actual cross-sectional size of the port by approximately 40% over U.S. Pat. No. 5,810,787 which relates to the 41% size increase shown in the vertical side cross-section shown in  FIGS. 16 and 17 . 
         [0064]      FIG. 28 , shows an alternative method of fabricating the bolus tip known as over-molding. In over-molding a conventional cylindrical tube is cut or skived to form part of the port and to also leave a portion of the tube to be a base for over-molding. This over-molding permanently attaches the molded part of the tube to the skived tube. This fabrication method provides a bolus that is the same outside diameter as the tube, which is ideal for catheters that reside in a blood vessel or other restricted space. The attached bolus method described in  FIGS. 1 through 26  is ideal for uses where the bolus will ultimately reside in a body cavity such as the stomach because the bolus provides a larger OD and resultant larger and deeper side ports. The elliptical bullet tip and tapered elliptical bolus edges of the new invention minimize any trauma caused by the larger attached bolus during insertion, removal or in-situ. 
         [0065]    While preferred embodiments of the invention have been described, it should be noted that the invention is not so limited and modifications may be made without departing from the invention. The scope of the invention is defined by the appended claims, and all devices that come within the meaning of the claims, either literally or by equivalence, are intended to be embraced therein.