in a centrifugal pump for pumping a fluid with central axial suctioning and radial discharging of the fluid to be pumped out of the impeller , the impeller includes an upper cover plate and a lower cover plate and multiple interposed blades therebetween . in the radial inner region , the blades extend essentially parallel to the rotation axis of the impeller in the axial direction of the pump and thus are upright , wherein said blades in the course radially outwards thereof are increasingly inclined or extend oblique .