Asymmetrical multi-lumen apheresis catheter with balanced flow rates

• Main Author: BEIL; CRAIG M
• Format: Patent
• Language: English
• Published: 14.11.2000
• Edition: 7
• Subjects: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROMTHE BODY; HUMAN NECESSITIES; HYGIENE; MEDICAL OR VETERINARY SCIENCE

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.