Microdialysis catheter and a method of making a microdialysis catheter

• US 8,229,546 B2
• Filed: 10/17/2007
• Issued: 07/24/2012
• Est. Priority Date: 10/18/2006
• Status: Active Grant

• Current Assignee: Maquet Critical Care AB (Getinge AB)
• Original Assignee: CMA Microdialysis AB
• Inventors: Liska, Jan, Falkén, Henrik
• Primary Examiner(s): Ho, Jackie
• Assistant Examiner(s): Anderson, Michael J
• Application Number:
  US12/446,098
• Publication Number:
  US 20100204565A1
• Time in Patent Office: 1,742 Days
• Field of Search: 604/29, 604/6.16, 600/424, 264/177.14
• US Class Current: 600/424
• CPC Class Codes: A61B 10/0045 Devices for taking samples of body liquids devices for taking blood samples A61B5/15
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/14528 invasively
• CPC Class Codes: A61M 25/0009 Making of catheters or other medical or surgical tubes

Abstract

The invention relates to a microdialysis catheter comprising a multilumen tube (10) and a membrane (11), said tube exhibiting at least two longitudinally arranged inner channels (13,14), said channels extending from a proximal (20) end of the tube to the distal end (21) of the tube, whereat through-holes (12,15) are provided, one from each of said at least two channels to the outside of said tube, said channels (13,14) blocked for passage of liquid distally of the respective through-holes, a tubular membrane (11) arranged circumferentially around the tube (10) such as to cover the at least two through -holes (12,15), said membrane is sealingly fastened (22) to the tube thereby forming a dialysis chamber (18) between the tube and the membrane.

Claims

1. A microdialysis catheter comprising a multilumen tube and a tubular membrane, said tube including two longitudinally arranged inner flow channels, said two longitudinally arranged inner flow channels representing an in-flow channel and an outflow channel, respectively, said flow channels extending from a proximal end of the tube to a distal end of the tube, wherein through-holes are provided, one from each of said two flow channels to the outside of said tube, said flow channels are blocked for passage of liquid distally of the respective through-holes, and the tubular membrane is arranged circumferentially around the tube such as to cover the two through-holes, wherein said tubular membrane is sealingly fastened to the tube, thereby forming a single dialysis chamber arranged between the tube and the tubular membrane and extending around their respective circumferences, wherein the flow channels are adapted to provide the same flow rate for the total in-flow, the total out-flow and the dialysis chamber flow, thus allowing a flow rate of 1-15 μ

l/minute, and wherein the tubular membrane is arranged such as to have a selective layer on the outer circumference of the tubular membrane to allow microdialysis of a target analyte.

2. A microdialysis catheter according to claim 1, comprising at least one further channel in the multilumen tube, said further channel extending between the proximal end of the tube to the distal end of the tube, said further channel adapted to house guide means and/or pressure measurement means and/or sampling/delivering means.

3. A microdialysis catheter according to claim 1, wherein the tube comprises extruded biocompatible polymeric material.

4. A microdialysis catheter according to claim 1, wherein the tubular membrane has a wall thickness of approximately 20-100 μ

m.

5. A microdialysis catheter according to claim 1, wherein the tubular membrane has a wall thickness of approximately 30 to 80 μ

m.

6. A microdialysis catheter according to claim 1, wherein the inner diameter of the tubular membrane is approximately 1000-3000 μ

m.

7. A microdialysis catheter according to claim 1, wherein the inner diameter of the tubular membrane is approximately 1000-2000 μ

m.

8. A microdialysis catheter according to claim 1, comprising means for detection of the position of the catheter, said means responsive to ultra sound while using the same for microdialysis purposes.

9. A microdialysis catheter according to claim 1, comprising means for detection of the position of the catheter, said means operable to impart opaqueness to X-rays to the catheter such that it is detectable using X-rays while using the catheter for microdialysis purposes.

10. A microdialysis catheter according to claim 1, wherein the total in-flow rate, the total out-flow rate and the dialysis chamber flow rate have the same rate, and the rate is 1-15 μ

l/minute.

11. A method of making a microdialysis catheter according to claim 1, comprising

extruding a multilumen tube, said tube including two longitudinally arranged inner flow channels, said flow channels extending from a proximal end of the tube to the distal end of the tube,

providing in said two flow channels through-holes, one from each of said two flow channels to the outside of said tube,

blocking said flow channels for passage of liquid distally of the respective through-holes,

arranging a tubular membrane circumferentially around the tube such as to cover the at two through-holes,

sealingly fastening said tubular membrane to the tube thereby forming a single dialysis chamber arranged between the tube and the tubular membrane and extending around their respective circumferences, wherein the tubular membrane is arranged such as to have a selective layer on the outer circumference of the tubular membrane to allow microdialysis of a target analyte.

12. A method according to claim 11 in which at least one further channel in the tube is provided during the extrusion.

13. A microdialysis catheter according to claim 1, wherein the longitudinally arranged inner flow channels have tubular walls distinct from a wall of the multilumen tube.