Transposition of the great arteries is a duct-dependent, cyanotic lesion, with the pulmonary artery arising from the left ventricle and the aorta from the right ventricle. This lesion needs a patent duct and an intracardiac shunt for mixing for survival. Balancing the two circulations can be challenging. The shunt via the duct is mainly L → R, but the intracardiac shunts might not be clearly directional. Pulmonary vascular resistance should be kept high with air and mild hypoventilation and an increase in systemic vascular resistance should be avoided.