[nradov]

Humans can't absorb any significant amount of water through the skin in a bath or shower. If the shower raises the bathroom humidity level enough the patient might breathe in a tiny amount of water but it's not enough to matter.

[DoreenMichele]

That really doesn't fit with my experience. Granted, I have a condition known to cause very bad aquagenic wrinkling, so I likely absorb water better through the skin than most people. But I know someone who doesn't have the same condition who was able to mitigate dehydration with soaking in a tub when they were too nauseous to take anything orally.

The OP's wife has a port and is currently getting fluids that way. He's expressed zero interest in that portion of my remark. I don't see much point in arguing this.