Charles,
Welcome to the neighborhood. I am sorry you are having to go through this. I am surprised you are looking at surgery after radiation. There are so many issues to face because of the radiation. Be sure and question this thoroughly with the doctors. I would believe hyperbaric oxygen chamber treatments would help the blood flow to allow speedier healing and recovery but with any active cancer, it would not be wise.
You are one of the few that have mentioned TPN feedings. I could not swallow and my PEG didn't allow me to feed that way so I spent weeks with TPN nourishment. Once I tried to cut the grass and the TPN bag disintegrated while I was mowing and I noticed a big puddle of white-ish liquid on the driveway which I traced to the portable bag I was wearing. It was a mess and my wife was not too kind about it

. The lawn looked great, though, so I suppose it was worth it

.
Best wishes for a quick recovery.
Ed