Patent ID: 7846127

Claim:
A multi-lumen catheter ( 1 ) comprising; an outer tube ( 2 ) having a front end side and a base end side and having an inner cavity including a first blood extraction lumen ( 21 ) and a second blood return lumen ( 31 ), a blood extraction port ( 22 ) which is open toward the front end side of the outer tube ( 2 ) in an axial direction of the outer tube ( 2 ) and communicates said blood extraction lumen ( 31 ) with an exterior of the multi-lumen catheter ( 1 ), and a blood return port ( 32 ) which is open toward the front end side of the outer tube ( 2 ) in the axial direction of the outer tube ( 2 ) on a front end side of said blood extraction port ( 22 ) and communicates said blood return lumen ( 31 ) with an exterior of the multi-lumen catheter ( 1 ); and an inner tube ( 4 ) having (a) an inner cavity constituting a lumen ( 41 ) for inserting a guide wire and (b) a front tip ( 42 ) of a tapered shape; said inner tube ( 4 ) being inserted in said outer tube ( 2 ), and being allowed to slide relative to said outer tube ( 2 ), the front tip ( 42 ) sliding with said inner tube ( 4 ) between a first open position and a second closed position and in said second closed position the front tip ( 42 ) is joined to the front end of said outer tube ( 2 ) to shut off the communication of said blood extraction lumen ( 21 ) and said blood return lumen ( 31 ) from the exterior of the catheter ( 1 ).