|This article is based off the alternate universe episode!
As such, details on the page may conflict with information from the regular storyline.
Riley was on an artificial lung while waiting for a lung transplant.
Callie got emergency approval to use an artificial lung on Riley even though the device hadn't been approved in children. Arizona disagreed and believed he should have been sedated and ventilated as he waited. Two weeks later, when Riley disconnected the lead to the artificial lung, Callie said they needed to take him back into the OR to hook it back up. However, Arizona objected, saying that he should be put back on ECMO instead. Then Callie noticed that Riley's oxygen levels were higher than they had previously been and he was breathing well. Callie said they needed to run more tests, but it was possible that Riley would no longer require a transplant.
They ran the tests and confirmed that he would no longer need a transplant and would be able to go home later in the week.
Riley's mother was in the hospital with him. She was elated to hear that Riley would no longer require a lung transplant.