Alright y’all. This one really has me stumped. In the NICU when we have a baby with a congenital heart defect we usually keep their sat parameters lower than normal. 85-90% for example. A long time ago someone told me that the reason we do this is because oxygen is a vasoconstrictor and it would cause a shunt of unoxygenated blood to the left side of the heart. But now I’m reading in several places that oxygen is a vasodilator and everything I thought I knew has gone out the window! Please help with an explanation as to why we keep these kids sat parameters low!