Wow, when I watched ER this past Thursday I was extremely worried for Carter. At the start of the episode he seemed really worn out and tired. Gates asked him if he was okay and he berkata yes.
Through as the episode went on I could tell oleh his body language that he was totally lying. John wasn't himself at all, he kept forgetting simple procedures and he was asking for tools that was right in front of him.
When everyone in the trauma room starting fighting my eyes were glued not to the people fighting but to Carter.
As soon as their was a break in the argument John collapsed!