Nitric Oxide During Bypass for Arterial Switch Operation

This trial will test if adding nitric oxide (NO) gas to the cardiopulmonary bypass (CPB) circuit in infants undergoing an arterial switch operation (ASO) for Transposition of the Great Arteries (TGA) changes the incidence of major postoperative adverse events (AEs). Major postoperative AEs include cardiac arrest, emergency chest opening, use of ECMO (machine that acts as an artificial heart and lung during surgery), and death. Participants will be randomised to receive oxygen plus nitric oxide (intervention arm) or oxygen without nitric oxide (control arm) during CPB.