Jokingly: "Yeah the terminal is right down alpha, turn left on bravo, and keep walking until you see the security guys, they'll help you the rest of the way..."
Seriously:
The best way I can think of to account for carry on luggage is to have each passenger account for their bags and any bag left over gets dropped. Obviously not a perfect method since there could be more than one malicious person aboard who might vouch for the "medical's" luggage, but better than hoping I guess... I'm in the camp with the folks that say all checked luggage better belong to people who are *on* the plane and that I wouldn't be anywhere near the plane until that was the case.
-Chip