I've heard there is a time limit that babies can be kept on a ecmo machine. Why and what do they do then?

ECMO. Typically one week is the time babies are on ecmo. Hopefully by that time lungs have recovered from the baselin insult or heart condition in improved or coerrected. Babies are slowly weaned from the ecmo support daily. While ecmo, babies are heparinised which can have significant possible complications.