We report the clinical application of a novel double lumen catheter for veno-venous extracorporeal lung assist (ECLA) and the use of a heparin-bonded hollow fiber membrane lung, in the treatment of newborn respiratory failure. The outer lumen of the double lumen catheter was 14 Fr and was used for blood drainage; while the inner 8 Fr catheter was used for blood return. The double lumen catheter was made of spiral wire reinforced polyurethane, with a wall thickness of 0.25 mm. The hollow fiber membrane was made of non-microporous polyolefin, and was not permeable to water or plasma. We used this system to treat a newborn patient with meconium aspiration syndrome. Heparin was infused continuously at a rate of 18-25 units/kg/h, equal to 1/3 of the usual amount when a non-heparin bonded ECLA system was used and maintaining the activated clotting time near 120 s. Bleeding from cutdown sites was negligible. Only the right internal jugular vein was sacrificed. The patient was successfully weaned from ECLA and appears normal one year following discharge.