Abstract:
Devices, systems and methods are disclosed for providing a direct visual indication of the relative inflationary condition of the balloon on a balloon catheter after insertion into the patient. In certain exemplary embodiments, a gastrostomy tube catheter is disclosed having a fluid feeding lumen and a balloon inflation lumen, a balloon communicating with the balloon inflation lumen, and an indicator strip having one end fixedly attached to the balloon and a free end movable along the length of the tube in accordance with the relative inflation and deflation of the balloon. The presence of the free end of the strip along an exposed portion of the gastrostomy tube serves as a direct visual indicator of a deflated condition of the balloon.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/700,056 filed Sep. 12, 2012, which is hereby incorporated by reference. 
     
    
     BACKGROUND  
       [0002]    This disclosure pertains generally to the field of medical devices, and more particularly to balloon type catheters, and especially gastrostomy tube catheters, for insertion into the body of a patient. 
         [0003]    There exists a variety of medical situations in which balloon catheters have been employed. Generally speaking, a balloon catheter refers to a catheter whose tip or forward portion has an inflatable balloon that either holds the catheter in place, such as for example in gastrostomy catheters used to provide nutritional feeding to a patient, or that can dilate the lumen of a blood vessel, such as for example in angioplastic procedures. In certain situations, it is particularly desirable to provide a direct visual indication to be able to verify the inflation and/or deflation condition of the balloon after the catheter has been inserted within the body of the patient and the balloon&#39;s condition can no longer be directly visually observed. 
         [0004]    One particular situation where direct visual verification is especially desirable involves gastrostomy catheters (variously also referred to as gastrostomy tubes, G-tube catheters, PEG catheters, and enteral feeding tubes or catheters). These catheters often need to be maintained for long term use by the user or patient at home. Over time, the balloon may eventually weaken and develop a puncture, leak or other condition causing a loss of fluid pressure inside the balloon. If not discovered in a timely fashion, the balloon&#39;s deflation could result in the catheter being inadvertently removed. 
         [0005]    Various methods and devices have been employed to provide a sensor or indicator useful for monitoring balloon pressure or the relative inflationary condition of the catheter balloon, but many suffer drawbacks in that they are too complicated, bulky, and/or expensive in their design and therefore not particularly suited for long term use, home use, and/or other situations. Thus, there is a need for improvement in this field and the present disclosure is directed to addressing those needs. 
       SUMMARY  
       [0006]    In various aspects, the embodiments disclosed herein are directed to unique devices, methods and systems for directly visually indicating the relative inflation condition of a balloon catheter. 
         [0007]    In one embodiment, a balloon catheter includes a tube having a main lumen and a balloon inflation lumen, a balloon communicating with the balloon inflation lumen, and an indicator strip having one end fixedly attached to the balloon and a free end movable along the length of the tube in accordance with the relative inflation and deflation of the balloon. The presence of the free end of the strip along an exposed portion of the tube serves as a visual indicator of a deflated condition of the balloon. 
         [0008]    In another embodiment, a balloon catheter includes a gastrostomy tube having a fluid feeding lumen and a balloon inflation lumen, a balloon communicating with the balloon inflation lumen, and an indicator channel extending along the surface of the balloon and at least a portion of the tube. The indicator channel contains a liquid contrast media. The presence of the liquid contrast media along an exposed portion of the indicator channel serves as a visual indicator of a deflated condition of the balloon. 
         [0009]    In yet another embodiment, a balloon catheter includes a gastrostomy tube having a fluid feeding lumen and a balloon inflation lumen, a balloon communicating with the balloon inflation lumen, and an indicator band substantially surrounding at least the exposed portion of the catheter. The indicator band has one end fixedly attached to the balloon and a free end movable along the length of the tube in accordance with the relative inflation and deflation of the balloon. The presence of the free end of the indicator band along an exposed portion of the tube serves as a visual indicator of a deflated condition of the balloon. 
         [0010]    Additional embodiment summaries can be understood from reference to the claims hereinafter, with it being understood that each claim is considered an embodiment disclosed. 
         [0011]    Further forms, objects, features, aspects, benefits, advantages, and additional embodiments of the present disclosure will be apparent to those skilled in the art from the detailed description and drawings included herein. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0012]      FIG. 1  illustrates one embodiment according to the present disclosure of a balloon type catheter with the balloon in an inflated condition inside the stomach of a patient; 
           [0013]      FIG. 2  illustrates an embodiment of a balloon type catheter in cross-sectional view with a visual inflation/deflation indicator indicating the deflated condition of the balloon; 
           [0014]      FIG. 3  illustrates the embodiment of  FIG. 2 , but with the visual inflation/deflation indicator indicating the inflated condition of the balloon; 
           [0015]      FIG. 4  illustrates an alternate embodiment of a balloon type catheter in elevation view with a visual inflation/deflation indicator. 
           [0016]      FIG. 5  is a partial cross-section taken along lines  5 - 5  in  FIG. 5 . 
           [0017]      FIGS. 6 and 7  illustrate further embodiments of a balloon type catheter in cross-sectional views with a visual inflation/deflation indicator indicating the deflated condition of the balloon. 
           [0018]      FIGS. 8 and 9  depict exemplary forms of markings to aid visualization of the inflation/deflation indicator. 
       
    
    
     DETAILED DESCRIPTION  
       [0019]    For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates. One embodiment of the invention is shown in great detail, although it will be apparent to those skilled in the relevant art that some features that are not relevant to the present invention may not be shown for the sake of clarity. 
         [0020]    Referring now to the drawings, there is shown in  FIG. 1  a gastrostomy tube balloon catheter  10  implanted within the stomach of a patient such as for feeding of nutritional solutions or delivery of medicines to the stomach and intestines. It should be understood that while  FIG. 1  depicts a gastrostomy tube balloon catheter, the present disclosure encompasses any other type of balloon in which there is a need to provide an external visual indicator of the inflation/deflation condition of the balloon inside the body. The catheter  10  is depicted with balloon  11  in its fully inflated condition serving as a retention system preventing unintended withdrawal of the catheter from the patient&#39;s stomach. The catheter  10  may be implanted using any one of a variety of methods including for example by percutaneous endoscopic gastrostomy (PEG). In this method, an endoscope is passed through the mouth, throat and esophagus into the stomach. The endoscope allows the doctor to choose the best location in the stomach to place the catheter  10 . The physician then makes a stoma  12  through the abdominal wall  14  and stomach  13  and the catheter  10  is passed through the stoma  12  into the stomach  13 . The balloon  11  is then inflated to retain the catheter  10  in place. 
         [0021]    In this illustrative embodiment as seen in  FIG. 2 , the catheter  10  includes a main lumen  15  extending axially between proximal and distal open ends  16  and  17 , respectively. The main lumen  15  is sized to permit delivery of nutrient solution feedings therethrough directly into the patient&#39;s stomach. Balloon  11  is situated towards the distal end  17  and communicates with an inflation lumen  18 . The catheter  10  includes an inflation port  19  in fluid communication with the balloon  11  through inflation lumen  18  separate from the main lumen  15 . An opening  21  in lumen  18  is provided in the outer wall of the catheter  10  to allow inflation and deflation of the balloon  11  by operation of a valve  20  controlling the opening and closing of the inflation port  19 . A removable cap  23  is provided to seal the proximal open end  16  of the catheter  10  during periods between feedings. A flexible strap  24  attaches cap  23  to catheter  10 . 
         [0022]    In order to allow the user or physician to verify that the balloon  11  is properly inflated, the catheter  10  is provided with a visual inflation/deflation indicator device  25 . As seen in  FIGS. 2 and 3 , the visual indicator device  25  is preferably in the form of a thin flat indicator strip  26  having a predetermined fixed length. As understood herein, the term “strip” is defined broadly to include any long and relatively narrow piece, body or component, including but not limited to a string, cord, filament, thread, line, wire, cable, braid, ribbon, tape, or band. Indicator strip  26  is attached to the balloon  11  at a first location  28  preferably positioned near the distal or forward end thereof and at a second location  29  intermediately positioned along the length of balloon  11 . Alternately, it should be understood that indicator strip  26  could be attached to more than two locations or even attached along the entire length thereof between locations  28  and  29 . The indicator strip  26  may for example be made of a suitable biocompatible material having the desired flexibility and strength characteristics to allow it to freely move as desired without becoming distorted, twisted or stretched. 
         [0023]    From location  29 , the indicator strip  26  freely extends into the inflation lumen  18  as seen in  FIGS. 2 and 3 . Alternately, as seen in  FIG. 4 , the catheter  10  may have a channel  31  provided separate from the inflation lumen  18  formed in or on the outer surface of the catheter  10  and balloon  11 . In either case, the indicator strip  26  is freely movable axially inside the inflation lumen  18  or channel  31  in accordance with the relative inflation and deflation of the balloon  11 . Since the indicator strip  26  has a fixed length, as the balloon  11  expands outwardly while being inflated the free end  26   a  of the indicator strip  26  will move in the direction opposite of arrow  27  until it reaches the position shown in  FIGS. 3-5  corresponding to the fully and properly inflated condition of balloon  11 . If balloon  11  is then deflated, the free end  26   a  of the indicator strip  26  will move in a direction along the direction of arrow  27  towards the position shown in  FIG. 2  corresponding to the fully deflated condition of balloon  11 . Thus, as depicted in  FIG. 2 , the presence of the indicator strip  26  along a portion of the catheter  10  extending outside of the patient serves as a direct visual indication that balloon  11  has suffered a rupture or leak and is no longer properly inflated. Conversely, as depicted in  FIGS. 3-5 , the absence of or retraction of the indicator strip  26  along the portion of the catheter  10  extending outside of the patient serves as a direct visual indication that balloon  11  has not suffered any rupture or leak and is properly inflated. 
         [0024]    In order to aid visualization of the indicator strip  26 , the strip  26  is shown highlighted with a visually contrasting color relative to the catheter  10 , which may itself be made of a substantially transparent or translucent material to allow as desired in order to facilitate visualization of indicator strip  26 . Alternately, or in combination therewith, strip  26  may be provided with distinctive markings or patterns  35  such as depicted in  FIGS. 8 and 9 . Optionally, as seen in  FIG. 4 , marking indicia  37  may also be placed along the outer surface of the catheter  10  to aid in the visualization of the inflated/deflated positions of the indicator strip  26 . Marking indicia  37  may optionally be placed at multiple locations along catheter  10 , including marking the fully inflated, fully deflated, and one or more intermediate locations indicating partially inflated/deflated conditions of balloon  11  so that the indicator strip  26  is also able to indicate a potential failure (e.g., slow leak) versus a full failure. 
         [0025]      FIGS. 6 and 7  depict further alternate embodiments of the visual inflation/deflation indicator device  25  of catheter  10 . In both  FIGS. 6 and 7 , the balloon of catheter  10  is shown in its inflated condition. As seen in  FIG. 6 , the device  25  comprises an indicator band  36  of fixed predetermined length substantially surrounding the balloon  11  somewhat akin to a blanket. As in the previous embodiments, the indicator band  36  has one end  36   a  fixedly attached to the balloon and extends in a channel formed on the surface of the balloon  11  and catheter  10 . The free end  36   b  of the indicator band  36  is movable along an exposed portion of the length of the catheter  10  in accordance with the relative inflation and deflation of the balloon  11 . The presence of the free end of the indicator band  36  along an exposed portion of the catheter  10  serves as a direct visual indicator of a deflated condition of the balloon  11 . 
         [0026]    A yet further embodiment of the visual inflation/deflation device  25  is depicted in  FIG. 7 . In this embodiment, the visual inflation/deflation device  25  comprises an indicator channel  40  containing liquid contrast media  46 . The indicator channel  40  is formed upon and extends along the surface of the balloon  11  and at least an exposed portion of the catheter  10 . As depicted in  FIG. 7 , the indicator channel  40  substantially surrounds the balloon  11  and catheter  10 . The space within indicator channel  40  contains the liquid contrast media  46 , which may for example be colored water. Inflation of the balloon  11  expands the volume of the portion of the indicator channel  40  extending along balloon  11  and causes the level of the liquid contrast media  46  within indicator channel  40  to drop until it is no longer visible along the exposed portion of catheter  10  extending outside the body of the patient. The presence of the liquid contrast media  46  along a portion of the indicator channel  40  extending outside the body of the patient thus serves as a direct visual indicator of a deflated condition of the balloon  11 . 
         [0027]    While the invention has 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 the preferred embodiment has been shown and described and that all changes, equivalents, and modifications that come within the spirit of the inventions defined by following claims are desired to be protected. All publications, patents, and patent applications cited in this specification are indicative of the level of skill in the art and are hereby incorporated by reference as if each individual publication, patent, or patent application were specifically and individually indicated to be incorporated by reference and set forth in its entirety herein. In addition, all references cited herein are indicative of the level of skill in the art and are hereby incorporated by reference in their entirety.