Actually, a lot of hospitals are implementing cameras in ORs. I know because I worked for a company that installed them.
They were used for recording surgeries, also for training new doctors who could watch procedures from another room and control the cameras in the room to see what was going on.
Another use was for the procedure to be monitored by the hospital administration. And by the nurses who would be setting up the room for the next operation.
My understanding, from my co-workers, was that some doctors really hated the cameras and that some of them would go into the rooms and turn the cameras to a wall to prevent anyone from seeing what they were doing.