Powerade zero really has helped me get throgh and get in extra fluids. Because it has electrolytes, it also helped me with nausea. Have you tried clear whey protein isolate? That will work to not only get in your fluids, but your protein at the same time. I recommend Oath for the clear protein. It does take some time for it mix. But once it's all mixed, it's absolutely delicious. Something else I do is, I put water in my protein shakes rather than nut milk. I'm a little sensitive to nut milk right now, whereas that is all I used before my surgery. Anyway, adding water, with ice and your protein powder, will also add to your hydration.