If you're pre-surgery, along with the other 10,469 things on your mind, you might want to make a few insurance-related phone calls so that you don't get smacked upside the head with half the bill, thanks to a little something called "amount allowable" (or "allowable amount" - either way, it's heinous).
To wit, your surgeon/anesthesiologist/hospital/whomever may choose to charge whatever they like, and your insurance company might choose to pay 70 or 80 percent not of what the surgeon/whomever has charged, but of what they consider the allowable amount for that entity. Said allowable amount may be a whole lot less than what your surgeon/whomever is charging. Like maybe, half as much. And then the coverage is only 70 or 80 percent of that. Which is even more less.
You will know when this has happened because several months after your surgery, when all is fine and dandy and life is a bunch of roses, you will find yourself post-lovely insurance lady (really, a sweetheart) phone call smacking your head into your computer screen, or another handy blunt object.
So, word to the wise. You're probably not going to like the answer whenever you get it, but at least you'll know. And as G.I. Joe always told us, that's half the battle.