Asymmetrical multi-lumen apheresis catheter with balanced flow rates

• US 6,146,354 A
• Filed: 05/24/1996
• Issued: 11/14/2000
• Est. Priority Date: 05/24/1996
• Status: Expired due to Term

• Current Assignee: AngioDynamics, Inc.
• Original Assignee: Horizon Medical Products
• Inventors: Beil, Craig M.
• Primary Examiner(s): Bockelman, Mark
• Application Number:
  US08/653,447
• Time in Patent Office: 1,635 Days
• Field of Search: 604/264, 604/280, 604/43, 604/4-6, 604/28, 604/523, 604/40.1
• US Class Current: 604/28
• CPC Class Codes: A61M 2025/0031 characterized by lumina for withdrawing or delivering, i.e. used for extracorporeal circuit treatment
• CPC Class Codes: A61M 25/0023 by the form of the lumen, e.g. cross-section, variable diameter
• CPC Class Codes: A61M 25/0029 characterized by features relating to least one lumen located at the middle part of the catheter, e.g. slots, flaps, valves, cuffs, apertures, notches, grooves or rapid exchange ports catheter shaft surface irregularities A61M2025/006
• CPC Class Codes: A61M 25/0032 characterized by at least one unconventionally shaped lumen, e.g. polygons, ellipsoids, wedges or shapes comprising concave and convex parts

Abstract

A multi-lumen intravenous catheter for use in treating a patient'"'"'s blood comprising an elongated cylindrical tube with at least first, second and third lumens formed inside. The first lumen is adapted to accept a guide wire for guiding the catheter during insertion into a blood vessel of the patient or therapeutics for introduction into the patient'"'"'s bloodstream. The second lumen is adapted to return treated blood to the patient'"'"'s blood vessel and has a smooth, circular or ellipsoidal cross-section. The third lumen is adapted to extract blood from the patient'"'"'s blood vessel for treatment and has a substantially elliptical or football-shaped cross-section and a cross-sectional area which is 10 to 30 percent larger than a cross-sectional area of the second lumen. Despite such unbalanced cross-sections, the second and third lumens have substantially equal blood flow rates during treatment of the patient'"'"'s blood. Also, the intake and return flow rates are improved for a given cross-sectional area of the catheter while the hydrostatic pressures within the lumens stay within maximum acceptable hydrostatic pressure limits for the patient.

Claims

1. A multi-lumen catheter for removing a patient'"'"'s untreated blood and its constituents for treatment by an extracorporeal blood treatment device and simultaneously returning treated blood and its constituents from said extracorporeal blood treatment device to the patient, said catheter comprising an elongated cylindrical tube with at least first, second and third lumens formed therein, said first lumen adapted to accept at least one of a guide wire for guiding said catheter during insertion into a blood vessel of the patient and therapeutics for introduction into the patient'"'"'s bloodstream, said second lumen being adapted to return said treated blood and its constituents from said extracorporeal blood treatment device to said patient'"'"'s blood vessel and having a substantially smooth, circular cross-section that provides smooth flow, and said third lumen being adapted to extract untreated blood and its constituents from said patient'"'"'s blood vessel for treatment by said extracorporeal blood treatment device and having a substantially smooth, ellipsoidal cross-section that provides smooth flow and a cross-sectional area which is at least 10 percent larger than a cross-sectional area of said second lumen, whereby hydrostatic pressures in said second and third lumens are maintained within a maximum acceptable hydrostatic pressure limit for a patient during treatment of said patient'"'"'s blood and its constituents at a given flow rate, and whereby flow rates in said second and third lumens are balanced at said given flow rate during treatment of said patient'"'"'s blood so as to enable said extracorporeal blood treatment device to return said treated blood and its constituents to the patient'"'"'s blood vessel via said second lumen at said given flow rate and simultaneously extract said untreated blood and its constituents from said blood vessel via said third lumen at said given flow rate.

2. A catheter as in claim 1, wherein said third lumen has tapered ends at respective ends along a major axis of said ellipsoidal cross-section of said third lumen so as to form a substantially football-shaped cross-section.

3. A catheter as in claim 1, wherein said third lumen has a substantially elliptical cross-section.

4. A catheter as in claim 1, wherein said third lumen has a cross-sectional area which is approximately 10-30 percent larger than a cross-sectional area of said second lumen.

5. A catheter as in claim 4, wherein said third lumen has a cross-sectional area which is approximately 25 percent larger than a cross-sectional area of said second lumen.

6. A catheter as in claim 1, wherein said catheter is sized to fit through a 13 french spreadable sheath, and said second and third lumens are sized such that when said given flow rate in said second and third lumens is approximately 250 mL/min., said hydrostatic pressure in said second lumen is approximately 310 mm Hg. and said hydrostatic pressure in said third lumen is approximately 160 mm Hg.

7. A system for extracorporeal treatment of a patient'"'"'s blood and its constituents, comprising:

an extracorporeal blood treatment device;

a multi-lumen catheter for removing the patient'"'"'s untreated blood and its constituents for treatment by said extracorporeal blood treatment device and simultaneously returning treated blood and its constituents from said extracorporeal blood treatment device to the patient, said catheter comprising an elongated cylindrical tube with at least first, second and third lumens formed therein, said first lumen adapted to accept at least one of a guide wire for guiding said catheter during insertion into a blood vessel of the patient and therapeutics for introduction into the patient'"'"'s bloodstream, said second lumen being adapted to return said treated blood and its constituents from said extracorporeal blood treatment device to said patient'"'"'s blood vessel and having a substantially smooth, circular cross-section that provides smooth flow, and said third lumen being adapted to extract untreated blood and its constituents from said patient'"'"'s blood vessel for treatment by said extracorporeal blood treatment device and having a substantially smooth, ellipsoidal cross-section that provides smooth flow and a cross-sectional area which is at least 10 percent larger than a cross-sectional area of said second lumen, whereby hydrostatic pressures in said second and third lumens are maintained within a maximum acceptable hydrostatic pressure limit for a patient during treatment of said patient'"'"'s blood and its constituents at a given flow rate, and whereby flow rates in said second and third lumens are balanced at said given flow rate during treatment of said patient'"'"'s blood so as to enable said extracorporeal blood treatment device to return said treated blood and its constituents to the patient'"'"'s blood vessel via said second lumen at said given flow rate and simultaneously extract said untreated blood and its constituents from said blood vessel via said third lumen at said given flow rate; and

a hub containing at least first and second extension tubes respectively connected to distal ends of said second and third lumens, said first extension tube providing a passageway from the distal end of said second lumen through said hub to an output of said extracorporeal blood treatment device, and said second extension tube providing a passageway from the distal end of said third lumen through said hub to an input of said extracorporeal blood treatment device so as to form a closed system in which untreated blood is extracted from said patient for treatment by said extracorporeal blood treatment device and treated blood is returned to said patient.

8. A system as in claim 7, wherein said third lumen of said catheter has tapered ends at respective ends along a major axis of said ellipsoidal cross-section of said third lumen so as to form a substantially football-shaped cross-section.

9. A system as in claim 7, wherein said third lumen of said catheter has a substantially elliptical cross-section.

10. A system as in claim 7, wherein said third lumen of said catheter has a cross-sectional area which is approximately 10-30 percent larger than a cross-sectional area of said second lumen.

11. A system as in claim 10, wherein said third lumen of said catheter has a cross-sectional area which is approximately 25 percent larger than a cross-sectional area of said second lumen.

12. A system as in claim 7, wherein said catheter is sized to fit through a 13 french spreadable sheath, and said second and third lumens are sized such that when said given flow rate in said second and third lumens is approximately 250 mL/min., said hydrostatic pressure in said second lumen is approximately 310 mm Hg. and said hydrostatic pressure in said third lumen is approximately 160 mm Hg.

13. A method of treating a patient'"'"'s blood and its constituents using an extracorporeal blood treatment device, comprising the steps of:

inserting a multi-lumen catheter into a blood vessel of the patient, said catheter comprising an elongated cylindrical tube with at least first, second and third lumens formed therein, said first lumen adapted to accept at least one of a guide wire for guiding said catheter during insertion into the blood vessel of the patient and therapeutics for introduction into the patient'"'"'s bloodstream, said second lumen being adapted to return treated blood and its constituents from said extracorporeal blood treatment device to the patient'"'"'s blood vessel and having a substantially smooth, circular cross-section that provides smooth flow, and said third lumen being adapted to extract untreated blood and its constituents from the patient'"'"'s blood vessel for treatment by said extracorporeal blood treatment device and having a substantially smooth, ellipsoidal cross-section that provides smooth flow and a cross-sectional area which is at least 10 percent larger than a cross-sectional area of said second lumen, said catheter further comprising a hub containing at least first and second extension tubes respectively connected to distal ends of said second and third lumens;

connecting said first extension tube to an output of said extracorporeal blood treatment device so as to provide a passageway from the distal end of said second lumen through said hub to said output of said extracorporeal blood treatment device;

connecting said second extension tube to an input of said extracorporeal blood treatment device so as to provide a passageway from the distal end of said third lumen through said hub to said input of said extracorporeal blood treatment device; and

said extracorporeal blood treatment device simultaneously extracting untreated blood and its constituents from said patient through said third lumen for treatment and returning treated blood and its constituents to said patient through said second lumen at substantially equal flow rates so as to balance flows in said second and third lumens and so as to maintain hydrostatic pressures in said second and third lumens within a maximum acceptable hydrostatic pressure limit for the patient during treatment of the patient'"'"'s blood and its constituents.