the present invention may be further understood with reference to the following description and the appended drawings , wherein like elements are referred to with the same reference numerals . the present invention relates to devices for the transfer of fluids to and from a target structure within a patient &# 39 ; s body over an extended period of time . in particular , exemplary embodiments of the present invention describe a venous access device that includes a branched distal tip for improved mobility , flexibility and flow . as shown in fig1 - 3 , a venous access device 100 according to an exemplary embodiment of the present invention comprises an indwelling catheter portion 102 a proximal end 108 of which is connected to a port device 104 . it will be understood by those of skill in the art that , although the device 100 is described as a port catheter system with a port device 104 , the device 100 may be any venous access device , such as piccs , central venous catheters ( cvcs ), dialysis catheters , and midline infusion catheters . for example , the catheter portion 102 may extend out of the skin to any known port connectable to external devices as desired and which may be sealed between uses such as , for example , a drainage bag for a drainage catheter system . as shown in fig1 , the catheter portion 102 includes a shaft 106 extending from the proximal end 108 to a distal end 110 which , in an operative position , is inserted into a target structure within a patient &# 39 ; s body . a proximal portion 118 of the shaft 106 includes a single first lumen 114 extending therethrough . a thickness 115 of a wall 117 of the shaft 106 around a circumference thereof may be selected as would be understood by those of skill in the art to achieve the desired properties ( e . g ., burst strength , flexibility , etc .) while the first lumen 114 is shaped to maximize its cross - sectional area without compromising these properties . at a distal end 110 , the shaft 106 splits into a plurality of branches 112 at which the first lumen 114 opens to two lumens 116 each of which extends through a corresponding one of the branches 112 . in a preferred embodiment , an outer diameter of each of the plurality of branches 112 is smaller than an outer diameter of the proximal portion 118 of the shaft 106 . in alternate embodiments , each branch 112 has substantially the same diameter or greater diameters as compared to that of the proximal portion 118 . in yet other embodiments , each branch 112 has a different size ( e . g ., length and / or diameter ) from other branches , and / or a different cross sectional configuration ( e . g ., round , oval , trapezoid , d - shaped , etc .) from other branches . in a preferred embodiment , the shaft 106 splits into two branches 112 , although it will be understood by those of skill in the art that the shaft 106 may split into any number of branches 112 . fig3 shows an embodiment of the catheter portion 102 in which the cross - section of lumens 116 are substantially d - shaped in the same manner as a lumen of a standard dual - lumen catheter . however , as shown in fig4 , either or both of the lumens 116 may be substantially round . in another embodiment as shown in fig5 , the venous access device of the present invention includes a dual - lumen catheter portion 102 . such dual - lumen devices are known in the art , and include devices such as dual - lumen ports ( as shown in fig5 ), piccs , and other implantable devices that include separate lumens that can be used to deliver different or the same materials such as therapeutic agents or contrast agents , or can be used to aspirate blood or other bodily fluids . in accordance with the present invention , the catheter portion 102 is divided into two sections 150 , 151 at the distal end 110 , with each section including one of the lumens that extend from the proximal end 108 to distal end 110 . each such section 150 is thereafter split into multiple branches 112 as described with reference to fig1 - 4 , above . the inventors have found that the use of branches 112 enhance the mobility and flexibility of the indwelling portion of the catheter portion 102 as compared to a single tube catheter . for example , in embodiments where the outer diameter of each of the branches 112 is smaller than the outer diameter of the proximal portion 118 , it will be understood by those of skill in the art that the distal end 110 of the device is more flexible than the proximal portion 118 . this enhanced flexibility allows for greater movement of the device 100 at its distal end 110 while implanted , such as with normal cardiovascular flow and pulse . the added flexibility and motion of the branches 112 inhibits fibrin sheath adherence and encrustation by blood or other bodily fluids , as sometimes encountered with single tube catheters . in use , fluid flowing distally through the first lumen 114 splits into the lumens 116 as it leaves the proximal portion 118 and enters the distal end 110 of the device 100 . in one embodiment , one or all of the lumens 116 taper toward the distal end 110 ( i . e ., a cross - sectional area of the lumen may grow gradually smaller from the proximal end of the corresponding branch 112 toward the distal end thereof ). in addition , any or all of the branches 112 may be angled relative to one another , depending upon a desired performance aspect . that is , longitudinal axes of the branches 112 may be set at any desired angle relative to a longitudinal axis of a distal end of the proximal portion of the shaft 106 to achieve a desired orientation of the branches 112 relative to one another . preferably , this angle is minimized to between 0 and 45 degrees , and more preferably between 0 and 15 degrees , such that the branches are in - line with the catheter longitudinal axis . as an example , the proximal portion 118 near the distal end 110 can define a first longitudinal axis and the first and second branches 112 can define second and third longitudinal axes , respectively . the a preferred embodiment , the second axis extends at an angle of less than 45 degrees from the first axis and the third axis is substantially co - axial with the first axis . those skilled in the art will understand that , for a catheter portion 102 including more than two branches 112 , the various branches 112 may be located in a single plane or a plurality of planes . the length of each branch is preferably less than about eight centimeters from most venous access applications . the distal end 110 , including the branches 112 may be delivered to a target area of the body in the same manner used for conventional split tip catheters as will be understood by those skilled in the art . the branches 112 may be temporarily bonded to one another or held together by an insertion device to facilitate the passage of the catheter portion 102 through intervening tissue with a minimum of trauma thereto . it will be understood by those skilled in the art that a catheter according to the present invention may include multiple lumens through a proximal part thereof so long as at least one of these proximal lumens opens to a plurality of lumens in separate distal branches of the catheter . that is , a catheter having a proximal part including two lumens will include at least three branches at a distal end thereof with each branch including a lumen open to one or more of the lumens of the proximal part . it will be apparent to those skilled in the art that various modifications and variations can be made in the structure and methodology of the present invention . thus , it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of the appended claims and their equivalents .
a venous access device comprises a catheter portion extending longitudinally from a proximal end to a distal end , the flexible shaft defining a lumen therein in combination with a plurality of branches separated from one another and extending distally from the flexible shaft .