Ive kicked the idea around to start a company that would attack this issue in a few different ways..
get an app or on the site, enter in some info..
an easy to remember 800 number that is answered 24/7..
the person who answers can unlock the info you saved via the app or web site - and call numbers for your X or your Y and even do it three-way / conference call.. and even call your Z or V after you hang up - to notify you've been detained or whatever.
I think people would pay for this, and it would be easy to freemium - as you could pre-roll a local bail bonds ad when called if freemium user..
I have some other ways to make this work even better with some added tech things.
could even have a set of info that is made available to paramedics / hospitals should they find your emergency card in wallet and such.
now I want to build this more, I'm guessing a premium phone number is not cheap these days, so keeping this in the ideas phase.