Method and apparatus for using dual-lumen catheters for extracorporeal treatment

• US 4,770,652 A
• Filed: 07/18/1986
• Issued: 09/13/1988
• Est. Priority Date: 02/12/1985
• Status: Expired due to Term

• Current Assignee: Sakharam D. Mahurkar
• Original Assignee: Sakharam D. Mahurkar
• Inventors: Mahurkar, Sakharam D.
• Primary Examiner(s): Pellegrino, Stephen C.
• Application Number:
  US06/888,251
• Time in Patent Office: 788 Days
• Field of Search: 604/4, 604/44-46, 604/264, 604/272, 604/280
• US Class Current: 604/6.16
• CPC Class Codes: A61M 2025/0031 characterized by lumina for withdrawing or delivering, i.e. used for extracorporeal circuit treatment
• CPC Class Codes: A61M 2025/0037 characterized by lumina being arranged side-by-side
• CPC Class Codes: A61M 25/003 characterized by features relating to least one lumen located at the distal part of the catheter, e.g. filters, plugs or valves catheter tips A61M25/0067
• CPC Class Codes: A61M 5/1582 Double lumen needles

Abstract

A patient dependent on extracorporeal treatments is subjected to minimal insertion trauma and pain both before and after a fistula operation. A phlebotomy method is disclosed using a veno-occlusive tourniquet or ligation occluding a venous segment at a location between the inlet and return openings of a dual lumen cathter so that a high blood flow rate can be obtained for an extracorporeal treatment system, thereby lessening or delaying the need for a fistula operation. Registration or alignment of the veno-occlusive tourniquet or ligation is ensured by an attachemnt to the catheter. Preferably the tourniquet or ligation includes an elastic band threaded to the attachment. If a fistula operation becomes necessary or has been performed, insertion trauma and pain is minimized by using a dual-lumen needle having a tapered distal end portion terminating in a beveled cutting edge. Preferably the needle has an outer tube of swaged stainless steel and an internal divider having a distal end portion matching and engaging with the reduced internal diameter of the tapered distal end portion of the outer tube.

Claims

1. A dual-lumen needle comprising

an elongated unitary hollow cylinder made of stainless steel and having a substantially constant diameter and wall thickness and a tapered distal portion terminating into a cylindrical end portion of reducing diameter tapering smoothly, to a single beveled distal tip having a sharp cutting edge for intiating punctures,

a longitudinal septum means disposed within said cylinder and dividing the interior of the cylinder into a pair of longitudinal lumens, one of said lumens extending along the full length of said cylinder so that it is open at said beveled distal tip, said septum means merging with the inside wall of said cylinder to terminate the other of said lumens a predetermined distance away form said beveled distal tip, and

at least one aperture formed in the cylinder wall near the end of said terminated lumen to provide access to that lumen through the side wal of the cylinder.

2. The dual-lumen needle as claimed in claim 1, wherein said aperture is in longitudinal alignment with the apex of the beveled distal end.

3. The dual-lumen needle as claimed in claim 1, wherein the longitudinal septum is centrally located and the lumens are of semicircular cross-section.

4. The dual-lumen needle as claimed in claim 1, wherein the longitudinal septum is an integral wall of a semicircular tube inserted into said elongated hollow cylinder.

5. The dual-lumen needle as calimed in claim 4, wherein the distal end portion of said semicircular tube has an outside diameter which precisely matches the inside diameter of the tapered distal end portion of the elongated hollow cylinder.

6. A dual-lumen needle comprising an elongated stainless steel tube of approximately constant diameter and wall thickness and having a swaged and tapered distal portion terminating into a cylindrical end portion of reducing diameter tapering smoothly to a single beveled distal tip, the beveled tip having a sharp cutting edge for initiating punctures, and a longitudinal septum means disposed within said stainless steel tube and dividing the interior of the stainless steel tube, the distal end portion of said longitudinal septum means engaging with the inside wall of said cylindrical end portion of reducing diameter, said longitudinal septum means providing a first lumen in said stainless steel tube having its distal opening in said beveled distal tip, and a second lumen inside said stainless steel tube having a distal opening provided by at least one aperture distal portion of said stainless steel tube to provide access to said secodn lumen through the side wall of said tube.

7. The dual-lumen needle as claimed in claim 6 wherein the longitudinal septum is the flat wall of an internal semicircular tube having its cylindrical wall flush with the inside wall of the cylindrical tube.

8. The dual-lumen needle as claimed in claim 6, wherein said aperture is at least partially in the wall of the tapered distal portion of said tube, and wherein said aperture and the apex of the beveled end of the tube are in longitudinal alignment.

9. The dual-lumen needle as claimed in claim 7, wherein the distal end portion of said internal semicircular tube has an external diameter matching the internal diameter of said cylindrical beveled tip of reduced diameter, so that a frictional fit is obtained between the cylindrical tube and the internal semicircular tube.

10. A dual-lumen hemodialysis needle for obtaining concurrent and continuous bidirectional blood flow between a fistula in a patient and a hemodialysis machine, said hemodialysis needle comprising

an elongated, straight, unitary cylindrical tube made of stainless steel and having a substantially constant diameter and wall thickness, the distal end portion of the tube being smoothly tapered with a gradual and uniform reduction of the circumference, and the distal end portion of said tube terminating into a cylindrical end portion of reducing diameter having a single sharpened and beveled distal tip defining a blood outlet opening and forming a cutting edge for initiating punctures, and

a planar internal divider means extending axially along the length of said tube to define respective blood intake and return lumens, the distal end portion of said internal divider being angled in the region of the tapered distal end portion of said tube to merge with the inner wall of said tube near the distal end of the tapered portion of said tube, the tapered portion of said tube including at least part of at least one aperture separated by said divider from said blood outlet opening so as to provide a blood inlet opening for said blood intake lumen,

wherein the bisecting plane of the internal divider, said aperture, and the apex of said beveled tip are approximately in longitudinal alignment, the bevel of said beveled tip sloping from the apex of said beveled tip proximally to terminate at a point geometrically opposite said divider from said aperture to thereby prevent mixing of the inlet and outlet blood flows.

11. The dual-lumen hemodialysis needle as claimed in claim 10, wherein the distal end portion of said tube includes a conically tapered portion providing at least some of said reduction of circumference and includes a cylindrical portion including said bevel and which extends proximally from said point at which said bevel proximally terminates to the distal end of said conically tapered portion.

12. The dual-lumen hemodialysis needle as claimed in claim 10, wherein the distal end portion of said internal divider merges with the inner wall of said tube at a point proximal of said point at which said bevel proximally terminates.

13. The dual-lumen hemodialysis needle as claimed in claim 11, wherein the distal end portion of said internal divider merges with the inner wall of said tube at a point at which said cylindrical portion including said bevel meets the conically tapered portion of said tube.

14. A hemodialysis method comprising

providing a dual-lumen needle comprising an elongated hollow cylinder having a tapered distal end portion to reduce the diameter of the cylinder, said distal end being beveled to form a cutting edge for initiating punctures;

a longitudinal septum disposed within said cylinder and dividing the interior of the cylinder into a pair of longitudinal lumens, one of said lumens extending along the full length of said cylinder so that it is open at said beveled distal end, said septum merging with the wall of said cylinder to terminate the other of said lumens a predetermined distance away from said beveled distal end;

at least one aperture formed in the cylinder wall near the end of said terminated lumen to provide access to that lumen through the side wall of the cylinder,

inserting said needle percutaneously into a blood vessel in the direction of blood flow, and

withdrawing blood from said blood vessel via said terminated lumen, treating the withdrawn blood in a hemodialysis machine, and returning the treated blood to said blood vessel via said lumen which is open at said beveled distal end.