Patent attributes
A blood treatment catheter pre-assembled with a stiffening tube is provided. The catheter includes a withdrawal lumen and a supply lumen each having distal split tube unjoined segments and an intermediate joined segment. The split tube segment of the supply lumen is provided with a sidewall aperture. The stiffening tube extends through the withdrawal split tip tube, out the distal end of the withdrawal tube, through the aperture of the supply split tip tube and through the split tip supply tube distal of the aperture, out the distal end of the split tip supply tube. When the stiffening tube is positioned inside the catheter, the aperture is adjacent to the withdrawal tube distal opening so as to minimize stiffening tube exposure and to provide a smooth exterior profile. In a preferred design, the tubes and their lumens, over their common length, are semi-circular to provide a circular profile for the catheter.