Sharlee,
While my kids are smaller than yours, ranging in age from 2-5, a couple of things came to mind when I read your post. I think one mistake we made was trying to prepare them too much for the fact that I was going to look a little beat up after the surgery. My husband took one look at how swollen I was and decided that he'd better make sure the kids were prepared. But what happened was that they were afraid to even look at me when I first came home. They actually ran and hid. And then when they finally warmed up, they said that I didn't look nearly as "freaky" as they were expecting. I should note that the two year old didn't hide. He welcomed me and didn't seem to notice or care that I looked crappy.
And one thing that I think we did right was to keep the kids' schedules as normal as possible. They knew that Mom was sick, but we tried not to let it throw them off too much.
And my hubby has been a godsend in running interference. He can tell when the noise is getting too much for me and kindly engaged them in an activity in another area of the house. This was good even before my surgery when I'd be feeling down and just needed some time to myself.
I'll be praying for you on the 9th.
Amy