A highly portable advanced adult and pediatric compact ECLS system is based around an integrated pump-oxygenator. The system includes a central a blood inlet and flow path extending along a general longitudinal axis of the system; a pump housing defining a pump inlet in fluid communication with the central blood flow path; an impeller rotationally received within the area of the pump inlet, wherein the impeller is magnetically supported and magnetically driven; an array of hollow fiber membranes configured for gas transfer within the system for oxygenation of blood flowing across the hollow fiber membranes, wherein the membranes include a covalently-bonded heparin-based bioactive surface, and wherein the blood flow path extends from the impeller to a position to flow perpendicular over the array of hollow fiber membranes; and a blood outlet configured to receive blood flowing past the array of hollow fiber membranes.