In your excellent episode guide you have in the description of this episode
NOTE: Viewer Jeff Holland notes that Elaine comments during this episode that no one would want to watch a bris; however in "The Bris" that is just what she and Jerry do!
After Kramer's Head accident, he calls George "Mike". This is in reference to Mike Costanza, the person who for the most part was the actual person George was based on.
It might be worth adding that Kramer also calls Elaine "Carol" in reference to Jerry's real life ex-girlfriend Carol Leifer, the person who the character of Elaine was also half based on.
Also Mike Costanza was not the basis of George's character, there was even a lawsuit over this. He was just someone Jerry knew in college and thought Costanza was a funny sounding name.
