Where's the fenestration?

For almost four years we've been fixated on Riley's blood oxygen level. We'd stare at the monitor wishing the number to nudge up, alarmed when it dropped too low, and desperately hoping each new surgery would bring it higher. So it's somewhat ironic that we're now concerned that his oxygen level is too high. Before the fenestration Riley's saturations were in the low 90s. That hasn't changed since the fenestration - he's stayed in the 90s and even toyed with the high-90s. That's disconcerting - if the fenestration is working, his saturations should drop (they were predicted to go into the mid-80s).

We've asked about this repeatedly and each time we've been reassured that the fenestration appears to be working correctly. They know this because they can see it on the echo. This afternoon a technician came in for another echo and couldn't find the fenestration. Within 30 minutes there were eight people in the room with him (lots of people in the room is never a good sign). They tried and tried, but they couldn't find it. They took a lot of images and headed downstairs.

The cardiologist just came in to tell us that the fenestration appears to be occluded. There is still some flow, but it's not as brisk as it was before. He is paging Dr. Karl to discuss a plan of attack. One possibility would be to give a drug called tPA to free the clot. But that assumes the problem is a clot and not a narrowing of the shunt. Another possibility is to head back up to the cath lab to investigate and possibly balloon the shunt open. We should know more soon.