christo,
generally speaking, when someone says 'blown out' they are referring to an image or area of one where the rgb values are 255, 255, 255....all white. and, with that in mind, there is only one way to treat it, like Ro says, 'fake it!'.
how you fake it is another story. you could cut and paste something in, clone something in, draw it in with a brush, airbrush it in and so on. the method is up to you.
if you're trying to make a selection in this area, you'll have to somewhat fake that too. in paint shop pro i can just draw in an area to be my selection with 'edit selection'. i believe
ps does this also but i dont know the command. quick mask maybe? not sure. you could also use a freehand point to point selection or just freehand.