for the purposes of promoting an understanding of the principles of the invention , reference will now be made to the embodiment 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 , such alterations and further modifications in the illustrated device , and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates . referring now more specifically to the drawings , fig1 shows a flexible , tubular catheter 20 . catheter 20 may be typically formed by extrusion , with subsequent treatments resulting in three functionally different portions 24 , 25 and 26 . internally , catheter 20 defines three passages 34 , 44 , and 54 . each of the passages is proximally in communication with an external tube and fixture , and each passage terminates in the distal portion 26 . balloon 30 is annularly disposed about portion 25 of catheter 20 and is sealingly fixed to portion 25 at proximal end 37 and distal end 31 . in general , balloon 30 may be of latex but other materials may also be appropriate . balloon 30 defines a lumen 35 overlying the outer surface 27 of catheter 20 and underlying the balloon 30 . the balloon 30 and its lumen 35 are longitudinally coextensive , extending approximately 2 . 2 cm . at the proximal end 37 and the distal end 31 the balloon is bound to surface 27 , such as with mercerized cotton thread or the like . passage 34 provides for inflation of balloon 30 . passage 34 extends through catheter 20 terminating blindly in distal portion 26 . opening laterally and underlying balloon 30 , two ports 36 are present in portion 25 . these ports 36 , approximately 0 . 035 inches in diameter , are located internally of balloon 30 and communicate between passage 34 and the balloon &# 39 ; s lumen 35 . inflation fluid may exit passage 34 at ports 36 , inflating the balloon 30 . tube 32 is connected with portion 24 of catheter 20 and communicates through a hole 33 with passage 34 . passage 34 is sealed proximally of hole 33 . from hole 33 to the distal tip 22 , catheter 20 is approximately 160 cm . long , more or less . tube 32 may be a cannula , and preferably is approximately 7 cm . long , ending proximally in a cap 39 and check valve assembly 38 combination . check valve assembly 38 is secured in fluid communication with tube 32 , and is designed so that when in the open position fluids may pass through it into and from balloon inflation passage 34 via tube 32 for inflating and deflating balloon 30 . once the balloon 30 is inflated to the desired diameter and pressure , the check valve assembly 38 may be shut to close access to tube 32 and passage 34 so that the balloon inflation pressure remains constant . a standard check valve assembly 38 and cap 39 may be used . the distal most portion of catheter 20 is portion 26 , terminating in a blunt distal tip 22 . the diameter of tip 22 is approximately uniform for a nominal 3 cm . proximal the distal tip , and the diameter gradually increases thereafter at taper 28 where it then continues approximately uniform substantially throughout the length of catheter 20 . the decreased diameter and taper 28 provides better patient acceptance during intubation . a cannula ( not shown ) may be inserted in the distal tip of the catheter 20 for stiffening the tip to facilitate steering the catheter into the small bowel 60 . portion 26 includes two internal passages 44 and 54 . passage 44 is the larger of the two and opens externally of the catheter 26 via side ports 40 . these side ports 40 are staggered to help prevent tissue blockage during use . present for a nominal 3 cm . proximal of taper 28 , side ports 40 are approximately 0 . 070 inches in diameter . passage 44 is continuous throughout the length of catheter 20 proximal of taper 28 . a standard screw cap fitting 46 is preferably connected with passage 44 at proximal end 42 . thus , a receptacle of contrast media or other material for infusion ( not shown ) may be connected to screw cap fitting 46 for injection into the small bowel 60 through passage 44 . the media enters the small bowel 60 through ports 40 . alternatively , screw cap 46 may be connected to suction to decompress the small bowel 60 . the smaller passage 54 runs beside passage 44 and is similarly continuous . it is proximally in communication with tube 52 . tube 52 ends proximally in fitting 58 having a luer type connector 56 for the connection of an air supply , suction source or the like ( not shown ). passage 54 is provided with side ports 50 which communicate with passage 44 . these side ports 50 , about 0 . 035 inches in diameter , are of smaller diameter than side ports 40 and are paired . catheter 20 is provided with two such pairs corresponding with the two most distal side ports 40 . these smaller side ports 50 enable a flushing and / or withdrawal of the bolus after flushing in order to clear any blockage of side ports 40 that results during aspiration of or infusion into the small bowel 60 . fig2 shows a partial , enlarged , plan view of catheter 20 of the embodiment in fig1 . the arrangement of side ports 50 as they relate to side ports 40 is shown . fluid passing through passage 54 exits side ports 50 , enters passage 44 and exits catheter 20 through side ports 40 . this creates a pressure change at port 40 which sufficiently dislodges any blockage of port 40 , enabling the medical procedure to continue . in addition , the injected fluid may be withdrawn through side ports 50 and out of the small bowel 60 through passage 54 . injection through passage 54 followed by withdrawal of the injected bolus , if desired , effectively flushes passage 44 . fig3 is a cross - section of catheter 20 taken through line 3 -- 3 of fig1 and looking in the direction of the arrows further demonstrating the relation of side ports 50 with side ports 40 . in the present embodiment the side ports 50 from the smaller passage 54 are not arranged coaxially with the larger passages 40 from passage 44 . instead the central axes of these side ports 40 and 50 intersect at an obtuse angle a . fig4 is a cross - section of catheter 20 taken along line 4 -- 4 in fig1 . infusion passage 44 is typically of larger diameter than sump channel 54 which , in turn , may be larger than balloon inflation passage 34 . fig5 is a cross - section of catheter 20 taken along line 5 -- 5 in fig1 demonstrating ports 36 as they communicate between passage 34 and lumen 35 . inflation fluid exits passage 34 through ports 36 . the fluid enters the balloon &# 39 ; s lumen 35 to expand the balloon material in conventional fashion . in fig6 a catheter 20 according to the present invention is shown positioned for small bowel enteroclysis . the catheter is inserted into the body , for example , through the oral cavity 66 , down the esophagus 64 , through the stomach 62 , past the pyloric sphincter 68 and into the small bowel 60 . the balloon 30 is shown inflated from a source of fluid ( not shown ) to block reflux of infused fluid into the stomach . the appropriate fluid , contrast media in the case of enteroclysis , is then infused from an infusion fluid source ( not shown ) in communication with passage 44 via screw cap fitting 46 . the media exits side ports 40 , creating relative hypotonia and filling the loops of the bowel 60 . during the filling , or upon withdrawal of fluid from the small bowel 60 subsequent to examination , the side ports 40 may become partially blocked with tissue or other material present . this blockage prevents or hinders further infusion or withdrawal . to remove the obstruction the ports 40 may be flushed with saline or the like . the saline , for example , is injected through passage 54 , entering the larger passage 44 through ports 50 . this creates positive relative pressure through the ports 40 sufficient to push the blockage away . alternatively , the saline dilutes the blockage so that it is less viscous and may be withdrawn when the saline bolus is pulled back through passage 44 with suction . thereby catheter 20 is flushed , and the medical procedure may resume . moreover , if the blockage causing material is part of small bowel 60 tissue then damage to such tissue is averted by the preceding method . once the subject medical procedure is completed , the balloon 30 may be deflated by opening the stopcock 38 . after balloon 30 deflation , the catheter 20 is removed from the body via the oral cavity 66 . 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 and modifications that come within the spirit of the invention are desired to be protected .
this invention relates to a catheter useful in examination of the small bowel which incorporates three lumens and a balloon and can thus prevent reflux of infused fluid as well as clear obstructions of the infusion ports .