Arthur: What was that?
Susan: French kiss.
Arthur: Really? Because the French always surrender. That was decidedly German.
Hobson passes away in the night, and no one notices until Arthur wakes the next morning, finds her unresponsive and cold, then screams for the nurse. Hobson was hooked up to monitors to warn the nurse (and Arthur) of this very thing, and that nurse would have been making regular checks on her during the night; it's what she's being paid to do. There is absolutely no way it could have played out this way, except in a film that needs sudden drama.