If I remember correctly, http://geck.gamesas.com/index.php/ToggleGodMode doesn't get reset when you load a save, so you should be able to load any other save (or start a new game), activate god mode, then load your near-death save with god mode active.
To help with any future occurrences, I second
Xepha's recommendation of using http://www.fallout3nexus.com/downloads/file.php?id=3729. This is exactly the kind of thing I wrote
CASM to help with.
Cipscis