Has anyone who SI's had a hospital stay(unrelated to SI)??

I go in on July 9th for Open Heart Surgery. I am 19 but my surgery will take place at a children's hospital. I have many scars on my stomach, and the upper part of my thighs are covered in them... I know they will see these scars, but i want to know what they will do... has anyone experienced something like this? what happened?

I also deal with an eating disorder and restrict/calorie count....what am i going to do about the food they feed me? i will be there for 7 days!

Any help is appreciated!