Belly Sling?

I have lymphedema, lipedeman, and dercums disease - with that said, I have what I say is a sagging belly. Sometimes my belly swells, sometimes it just gets heavier and sags (low). I'm a big woman and this sag just wreaks havoc on my lower back and at times my bladder. Is there such a thing as a belly sling? I have seen some for pregnancy but they aren't big enough.
Any suggestions would be greatly appreciated.
Christine
Any suggestions would be greatly appreciated.
Christine