Patent ID: 7008395

Claim:
A multi-lumen catheter comprising: a) an elongated cylindrical tube having a distal and a proximal end and a lumen therethrough; b) a transverse septum extending from the distal end to the proximal end of the tube within the lumen of the tube and dividing the tube into a return passageway and a withdrawal passageway, the withdrawal and return passageways open at the distal and proximal ends of the tube; c) return septum extending from the distal end to the proximal end of the tube and dividing the return passageway into first and second return lumens; and d) a supporting septum extending from the distal end to the proximal end of the tube and dividing the withdrawal passageway into first and second withdrawal lumens, the supporting septum supportingly engaging the transverse septum to support the transverse septum and deter deflection of the transverse septum, wherein the withdrawal lumens have a total cross-sectional area greater than or equal to that of the total cross-sectional area of the return lumens.