Patent attributes
A blood pump comprises a pump casing having a blood flow inlet and a blood flow outlet connected by a passage, and an impeller rotatable about an axis of rotation. A surface of the impeller faces a surface of the pump casing spaced from said surface of the impeller by a clearance, the clearance being in fluid connection with the passage at a clearance transition point. At least one wash out channel extends through the impeller and is in fluid connection with the passage via a first opening and with the clearance via a second opening. The first opening of the wash out channel is arranged in an area of the impeller that is under a higher pressure than the clearance transition point so as to cause a blood flow from the first opening through the wash out channel and the clearance to the clearance transition point.
