One note on air tubes and such- care should be exercised to ensure that the tube is not too long or big around, as the capacity to draw fresh air in through the tube is directly related to the volume of air the tube can contain and the volume of the victims lungs. If the tube is too long/large, the victim will simply be re-breathing their own air.
I would like very much to know what comes after the break down? When your body and mind are immersed in snot/tears/hate and fear..
Who says you are going to get out of there? John might forget where he left you - - - :o