Couple of things to get you started. A lot of post surgery wound care really depends on where the wound is, how bit the wound site is, and how invasive the surgery. But here are some quick thoughts the cover most surgeries and are outside of monitoring the wound site for redness, swelling/infection.
Keep the cage clean. You may have to clean the cage a couple of times a day. If you are using substrate bedding, discard that and put in a layer of soft fleece bedding, I prefer light colors, white, pale yellow etc so that I can see if there is any discharge or bleeding more easily.
You may need to remove the wheel for a bit to keep the wound clean and to help the wound heal. For larger incisions in the abdomen I tend to take it out for longer, other locations and smaller incisions that heal quickly it goes back in sooner.
Monitor appetite. Get a couple of oral syringes from the vet for syringe feeding just in case, and have on hand a pate style canned cat food. If he doesn't eat you'll need to syringe feed.
Get pain medication from the vet. We always give pain medication for about 3 days after surgery. It really helps a lot. Its been my experience that they really do not bother their stitches if they are provided pain medication for a few days. Plus pain medication can make them sleepy. Sleepy isn't a bad thing, especially if you have one that is missing their running wheel.
Post-surgery, you may find your hedgehog needs their cage warmer. I've never had one die from anesthesia, but I have had some that woke up very slowly or required more warmth for the first 24-48 hours afterwards. It really just depended on the hedgehog on who needed more and who didn't.
Post if you have questions and keep us updated.