Patent ID: 6869412

Claim:
An intravascular device for removing plasma fluid from a patient's blood, said device comprising (a) a dual lumen intravascular catheter having open and closed ends wherein the lumina are coaxially disposed as a central core channel and a circumferential outer channel within said catheter, said channel containing the inner lumen, said inner lumen having near and distal ends and being open at both the near end and distal end of the device; (b) inlet and outlet tubing ports at the near open end of the inner lumen and the open end of the outer lumen respectively, said inlet port communicating with the inner lumen configured to allow a fresh hyperosmotic fluid to pass into the inner lumen and out through the distal open end of the core channel and then flow back through the circumferential outer lumen and out of the device through the outlet tubing port, which communicates with the outer lumen; (c) the outer lumen being defined by the circumferential channel of the coaxial configuration and formed between the core channel and the inner surface of the outer catheter wall comprising a semipermeable membrane and having its outer surface so positioned to directly contact whole blood passing by it; (d) said inner lumen being formed from a nonpermeable polymer, so arranged as to permit a continuous supply of fresh hyperosmotic fluid to the outer lumen and thereby exert sufficient osmotic pressure to force plasma fluid from the blood, crossing from the outer to inner surfaces of the circumferential semipermeable wall, into said outer lumen and thence out the outflow port, said device further comprising luer locks disposed at each of the ends of the inlet and outlet ports, and wherein the luer lock disposed at the end of the outlet port further comprises a guide wire having a hub at one end thereof, said hub being removably secured to said luer lock.