Patent ID: 7282041

Claim:
A multi lumen catheter comprising: an outer tube having an inner cavity constituting a blood extraction lumen, and a blood extraction port which is open at an end facing the front end side in the axial direction and communicates said blood extraction lumen with the exterior of the catheter; an inner tube having (a) an inner cavity constituting a blood return lumen and (b) a blood return port for communicating said blood return lumen with the exterior of the catheter; and a guide wire tube for inserting a guide wire and having (a) an inner cavity constituting a lumen for inserting the guide wire, and (b) a front tip of a tapered shape; wherein said blood extraction lumen is defined by an inner surface of said outer tube and outer surfaces of said inner tube and said guide wire tube, and wherein said inner tube and guide wire tube are inserted in said outer tube, and are allowed to slide relative to said outer tube, and the front tip slides with said guide wire tube between a first open position and a second closed position and in said second closed position the tip is joined to the front end of said outer tube to shut off communication of said blood extraction lumen and said blood return lumen from the exterior of the catheter.