Patent ID: 7210898

Claim:
A centrifugal pump for pumping biological fluids such as blood, the pump comprising: a housing defining a pump chamber; a shaft within the pump chamber, the shaft defining an axis of rotation; an impeller within the pump chamber, the impeller rotatable about the axis of rotation; a fluid inlet in communication with the chamber that is external to the impeller; a fluid outlet in communication with the chamber; and means for removing gas from a position along the axis of rotation where the gas tends to accumulate, wherein the means for removing gas is positioned near the fluid inlet; and wherein the means for removing gas further comprises: a shroud surrounding a portion of the shaft, the shroud forming a collection space to collect the gas; a vent in communication with the collection space; suction tubing in communication with the vent; and a suction device coupled to the suction tubing to remove the gas from the collection space.