You could start with a blank drawing (no blocks), then INSERT the drawing with the edited blocks into it and explode. The blocks in the inserted drawing would be the current definition *if* they didn't exist in the destination drawing before INSERTing the block drawing.
In your working drawing, if no blocks with the same name exist as objects, but their definition is still in the drawing, use PURGE to remove the definition so that the edited block definition will be current on INSERT or however you get them in there.
This is what templates and tool palettes are for. Think ahead to future work, get it right (blocks, layers, all configuration), then discard (PURGE) the out-of-date block definitions so that you don't go through this with every new drawing project. There is no hot key for globally updating blocks.
