US Patent 8241245 Co-axial catheter

A co-axial catheter assembly including a first lumen having a first distal end and a first proximal end, and a second lumen having a second distal end and a second proximal end. The second lumen extends co-axially with the first lumen, wherein the second lumen is at least partially disposed within the first lumen and the second distal end extends distally of the first distal end. A catheter hub provides for fluid connections of the inner and outer lumens with respective extension tubes, and includes spacers that maintain the proximal end of the inner lumen concentrically within the proximal end of the outer lumen and the distal end of the inner lumen concentrically within the distal end of the outer lumen, respectively. Methods of manufacturing and of inserting the catheter are also disclosed.