if the collision is so bad that you need to be cut out, i would imagine that all sorts of reactive safety features like fuel cut off, airbags and the such like would have been activated, along with something to unlock the doors.
failing that, if you are in a really mangled wreck, they are going to cut the car apart from around you anyway. i've seen them take the roof off quick and clean, and then proceed to cut away and remove most of the rest including doors, till they had easy access to just the driver in his seat, which was lifted out in one piece.