While the surgeons are operating on Annie, the tumor patient, and she starts bleeding out, the camera goes to a male scrub nurse who says "pressure's dropping." If you look closely at him, he's played by the same guy who plays Joe the bartender.
If Tomorrow Never Comes was written by Garth Brooks and Kent Blazy and was released by Garth Brooks in 1989. It was later recorded by Ronan Keating in 2002.
At 37:26 of the episode the camera pans to a doctor that looks like Richard (James Pickens Jr.) but it is clearly not him. Richard is listed as credit only in this episode, there isn't another actor credited as this mystery character.
In S1:E6 at about 1:24, the cup in George's left hand is the same cup as the one in Richard's right hand later on in S17:E14 at about 40:57 that he hands to Catherine.