Thanks for the advice! While we were in, they consulted with infectious disease and hematology (at my insistence). They checked him for a bunch of infectious diseases including tick born illnesses, and also checked blood clotting factors.

I tried to post this on other boards, but this one was first and I didn't know it would only let me post once. I posted here because one of the doctors they told me to follow up with was a rheumatologist.

He needed a break from the hospital. I'm most likely going to take him to another emergency department tomorrow at a hospital about an hour away. It's a teaching hospital and where he has all of his heart surgeries.

Oh, and the hematologist who saw him said to follow up with their office in 2 weeks! What?!?!