The line "I'm nobody who are you/Are you nobody too?" is from the poem "I'm Nobody! Who are you?" by Emily Dickinson.
Ketamine is frequently described as a veterinary tranquilizer, however it is also used in humans as a sedative for painful and invasive procedures that don't take long. It can also be given in conjunction with opiates like morphine to relieve severe pain as well as muscle spasms.
Jason Wiles, who plays Alexander Gammon, played police officer Maurice "Bosco" Boscorelli in another police procedure drama Third Watch (1999).