Methods and apparatus are provided for removing emboli generated during a surgical procedure comprising a catheter having proximal and distal ends, a lumen extending therethrough, an occlusive member affixed to the distal end, and at least one blood intake port disposed in a lateral surface of the catheter. The occlusive member preferably is disposed in a treatment vessel, and the blood intake port, when uncovered, permits a portion of the antegrade flow from a host vessel to be diverted into the lumen of the catheter. A pressure differential caused by the blood intake from the host vessel establishes a venturi-effect suitable for manipulating flow in the treatment vessel. The flow characteristics may be manipulated via the intake port to direct emboli into the lumen of the catheter for subsequent removal.