An extracorporeal system for lung assist comprising: a housing, the housing comprising a blood flow inlet in fluid connection with a pressurizing stator compartment , a fiber bundle compartment in fluid connection with the pressurizing stator compartment via a flow channel formed within the housing which extends tangentially or within 5 degrees of tangentially from the pressurizing stator compartment and extends to a manifold in fluid connection with the fiber bundle compartment , and a blood flow outlet in fluid connection with the fiber bundle compartment ; an impeller rotatably positioned within the pressurizing stator compartment for pressurizing blood entering the pressurizing stator compartment from the blood flow inlet , the impeller centrifugally forcing blood radially outward into the flow channel ; a fiber bundle positioned within the fiber bundle compartment , the fiber bundle comprising a plurality of hollow gas permeable fibers formed in at least one cylindrical bundle, the plurality of hollow gas permeable fibers being adapted to permit diffusion of gas between blood and an interior of the plurality of hollow gas permeable fibers, the plurality of hollow gas permeable fibers being positioned such that blood flows around the plurality of hollow gas permeable fibers when flowing through the fiber bundle compartment, the plurality of hollow gas permeable fibers extending perpendicular or within 5 degrees of perpendicular to the direction of bulk flow of blood through the fiber bundle compartment from the flow channel to the blood flow outlet wherein the bulk flow of blood through the fiber bundle is in an axial or within 5 degrees of an axial direction, a gas inlet in fluid connection with the housing and in fluid connection with inlets of the plurality of hollow gas permeable fibers, and a gas outlet in fluid connection with the housing and in fluid connection with outlets of the plurality of hollow gas permeable fibers. a housing, the housing comprising a blood flow inlet in fluid connection with a pressurizing stator compartment , a fiber bundle compartment in fluid connection with the pressurizing stator compartment via a flow channel formed within the housing which extends tangentially or within 5 degrees of tangentially from the pressurizing stator compartment and extends to a manifold in fluid connection with the fiber bundle compartment , and a blood flow outlet in fluid connection with the fiber bundle compartment ; an impeller rotatably positioned within the pressurizing stator compartment for pressurizing blood entering the pressurizing stator compartment from the blood flow inlet , the impeller centrifugally forcing blood radially outward into the flow channel ; a fiber bundle positioned within the fiber bundle compartment , the fiber bundle comprising a plurality of hollow gas permeable fibers formed in at least one cylindrical bundle, the plurality of hollow gas permeable fibers being adapted to permit diffusion of gas between blood and an interior of the plurality of hollow gas permeable fibers, the plurality of hollow gas permeable fibers being positioned such that blood flows around the plurality of hollow gas permeable fibers when flowing through the fiber bundle compartment, the plurality of hollow gas permeable fibers extending perpendicular or within 5 degrees of perpendicular to the direction of bulk flow of blood through the fiber bundle compartment from the flow channel to the blood flow outlet wherein the bulk flow of blood through the fiber bundle is in an axial or within 5 degrees of an axial direction, a gas inlet in fluid connection with the housing and in fluid connection with inlets of the plurality of hollow gas permeable fibers, and a gas outlet in fluid connection with the housing and in fluid connection with outlets of the plurality of hollow gas permeable fibers. <EOS>