Oh yeah... I actually lost most of my voice BEFORE surgery from the incessant coughing I had been doing as a result of the CHF i was in (I was REALLY sick)
Having the tube down my throat for over a month (I was REALLY sick...) didn't help matters and they even did a procedure after taking me off the vent to set my vocal chords back in their proper place. It really took me almost a year to regain my full voice but it's back and fine now. I was talking without much sign of a problem a few weeks after getting home, about 10-12 weeks post-op.
Again, I was REALLY sick. =)
Don't push it. Your voice WILL come back. It's frustrating for a while I know, one word sentences were all I could muster for weeks on end and you had set your ear practically on top of my face to understand me.
Breath, lots of breathing, use that spirometer if they gave you one, usually something with a ball that you have to raise into the air by blowing into a tube. Drink light liquids, soft drinks like orange juice, water, fruit juice, tea. Avoid carbonated beverages for a while, and anything alcoholic.
Humming seemed to help sometimes, it's hard to do but if you can get even just a little, quite sound to come out and keep working on it, things seem to move quicker.
Be patient, get a notepad and a pencil.
My wife wrote out the alphabet on a sheet of notebook paper along with some common phrases that I could point to when I needed something and couldn't communicate it verbally...