The celebrity callers at the beginning of this episode are Betty Comden and Adolph Green, who voice Linda & Walter, the married couple who are lost on their way to the Antique Mart. Comden and Green, always billed in alphabetical order, were both song writers, whose 60-year-careers of film and stage collaboration include On the Town (1949), Singin' In The Rain (1952), It's Always Fair Weather (1955), and Bells Are Ringing (1960).
In the hospital, outside of Artie Walsh's room, is a cut-out art print of a lake at sunset. This is the same framed piece found in the office of Michael Scott (Steve Carell) in The Office (2005).
When Roz says she is interested in a 19-year-old, Frasier says "Koo-koo-ka-choo, Mrs. Robinson!" He is quoting the song Mrs Robinson by Simon and Garfunkel, and referring the movie The Graduate (for which the song was written), in which Mrs Robinson is the name of an older woman who seduces a much younger man. Furthermore, one episode earlier, one of the celebrity callers was Art Garfunkel, one of the song's two singers.
Niles says Maris hasn't had much experience with hospitals aside from common childhood things: tonsils, adenoids, and forced feedings. But in season 7's episode To Thine Old Self Be True, Niles reveals Maris was always heavy as a child and was obsessed with keeping her weight down her whole adult life.
The second celebrity caller in this episode is Adolph Green who plays Walter and proclaims that he isn't lost after his wife calls into the show asking for directions.