I had single radical neck dissection after having malignant tonsil and lymph involvement. It was a tough surgery. They will typically want to put in a feeding tube at the surgery since most will have radiation on the neck and your swallowing is very difficult after the surgery, then the radiation makes it worse. I fought the feeding tube, I didn't want one, and they didn't put one it. I was able to swallow, eat and drink although it was difficult. I had to sleep in a chair for a few weeks as when I would lay down I got drainage in my throat and it would choke me. No big deal, just had to go to the restroom once an hour and rinse/spit.
It's a hard one, but lots here have had it. Let me know if I can answer anything for you even though I only had a single.