Dual lumen catheter

1 . A catheter, comprising:

an infusion lumen wall extending to an infusion lumen tip, wherein:

the infusion lumen wall surrounds an infusion lumen;

the infusion lumen is in fluidic communication with an infusion line of a blood filtration system; and

the infusion lumen discharges fluid at the infusion lumen tip, the fluid supplied by the blood filtration system;

a withdrawal lumen wall extending from a proximal section to a withdrawal lumen tip, wherein:

the withdrawal lumen tip is included in a distal section of the withdrawal lumen wall;

the withdrawal lumen wall surrounds a withdrawal lumen;

the withdrawal lumen is in fluidic communication with a withdrawal line of the blood filtration system;

the infusion lumen is isolated from the withdrawal lumen;

the withdrawal lumen is located and arranged to receive fluid from vasculature of a patient at the withdrawal lumen tip;

the withdrawal lumen wall includes a polymeric material;

the withdrawal lumen wall has a first structural support section including one or more structural supports embedded in the polymeric material;

the withdrawal lumen wall has a second structural support section including the one or more structural supports, wherein the second structural support section is separated from the first structural support section by a first trimming section of the polymeric material located between the first structural support section and the second structural support section, wherein the first trimming section includes a continuous fluid-impervious outer wall section and does not include the one or more structural supports, and wherein the first trimming section is included in a plurality of trimming sections, which include a continuous fluid-impervious outer wall section and which do not include the one or more structure supports, that are included in the distal section of the withdrawal lumen wall and are individually arranged and spaced apart from each other to ease cutting during user-customization of a length of the withdrawal lumen wall between a hub of the catheter and the withdrawal lumen tip;

the withdrawal lumen wall extends beyond the infusion lumen tip to longitudinally offset the withdrawal lumen tip from the infusion lumen tip;

the withdrawal lumen wall includes a transition section extending between the proximal section and the distal section; and

the catheter includes a central axis, and the transition section extends across the central axis of the catheter.

2 . The catheter of claim 1 , the catheter comprising:

a proximal portion including the hub;

wherein the withdrawal line is a negative pressure withdrawal line that is connected to a negative pressure source of the blood filtration system providing a negative pressure in the withdrawal lumen;

the infusion lumen is in fluidic communication with a positive pressure infusion line that is connected to a positive pressure source providing a positive pressure in the infusion lumen;

a flexible septum extending between the withdrawal lumen and the infusion lumen, wherein:

the flexible septum is coupled with the withdrawal lumen wall and the infusion lumen wall; and

the flexible septum isolates the withdrawal lumen from the infusion lumen; and

wherein, in use, the flexible septum deflects toward the infusion lumen to offset a difference in fluid flow between the infusion lumen and the withdrawal lumen to equalize a pressure differential between the positive pressure in the infusion lumen and the negative pressure in the withdrawal lumen to compensate for fluid removal by the blood filtration system attached to the withdrawal lumen such that less fluid is returned to the infusion lumen than withdrawn by the withdrawal lumen.

3 . The catheter of claim 2 , further comprising a transducer capable of measuring one or more fluid flow characteristics of fluid flowing in the vasculature of the patient.

4 . The catheter of claim 3 , wherein the transducer is sized and shaped for insertion into the vasculature of the patient.

5 . The catheter of claim 3 , wherein the transducer is capable of measuring one or more fluid flow characteristics between the catheter and a vasculature wall of the patient.

6 . The catheter of claim 3 , wherein the transducer is capable of measuring one or more fluid flow characteristics around the catheter.

7 . The catheter of claim 2 , wherein the withdrawal lumen tip is located more distally than an infusion lumen tip to inhibit recapture of non-circulated fluid dispensed via the infusion lumen tip.

8 . The catheter of claim 1 , wherein the first structural support, the second structural support and the first trimming section are located in the proximal section of the withdrawal lumen wall.

9 . The catheter of claim 8 , wherein a distal section of withdrawal lumen wall includes:

a third structural support section including the one or more structural supports embedded in the polymeric material; and

a fourth structural support section including the one or more structural supports, wherein the fourth structural support section is separated from the third structural support section by a second trimming section of the polymeric material located between the third structural support section and the fourth structural support section.

10 . The catheter of claim 9 , wherein the second trimming section is included in the plurality of trimming sections, and the plurality of trimming sections are included in the distal section of the withdrawal lumen wall.

11 . The catheter of claim 1 , wherein the withdrawal lumen wall includes:

a third structural support section including the one or more structural supports embedded in the polymeric material; and

a fourth structural support section including the one or more structural supports, wherein the fourth structural support section is separated from the third structural support section by a second trimming section of the polymeric material located between the third structural support section and the fourth structural support section.