This invention is an apparatus for treating a patient including a catheter (12) having a distal end (14), and a proximal end (16). The distal end (14) has an orifice (18) through which a fluid can flow. The distal end (14) has a port (20) through which fluid can flow. The port (20) is adjacent to, but apart from, the orifice (18). The apparatus (10) includes a mechanism (22) for controlling the size of the port (20) that is open. The controlling mechanism (22) is disposed over the port (20), and able to close the port (20). The distal end (14) has an end marker (34) disposed about the orifice (18) which appears in an image of an imaging device. The distal end (14) has a plurality of holes (32) having an elongate shape disposed essentially in parallel with the longitudinal axis of the catheter (12) with smooth edges so blood cells are not damaged as they pass through the holes (32). Methods of using the device are also disclosed.
