My kiddo just had her large and patched via OH on the 29th... here's is what our experience was like.
1st my child is 4, so I kept her info very simplified. She knew when she had the echo they were "looking inside" her. So since she loved doctors I told her that when they were looking they found that her heart was sick and we were going to take a trip to St Louis where my nephew goes when his heart is sick. At this point we discussed there would be lots of really nice doctors and nurses. Since she is a very out going child she was excited for a trip (without her sister) and to get to meet LOTS of new people. She started calling it a party. This is also because my nephew told her that there were lots of toys and fun things to do there once she started feeling better.
2nd arrived the day before for pre-op labs and tests. Again, being a children's hospital, she was enjoying all of the attention. I continued to remind her that we were there to fix her sick heart, with her humor she would just laugh and say "yes mom, I know but it is more fun to call it a party" The surgeon explained the procedure in front of her, but didn't discuss the before and after. I was waiting until my pre-surgery consult with the anesthesia nurse to get more details and then prepare her. this was our last appointment of the day. they said that they would give her sleepy juice so she wouldn't even care being separated from me. Then the put her under with a mask. So no needles to warn her about. They told us that the her procedure repair would only take roughly 20 minutes. The rest of the 3 to 4 hours was sedation put opening, "stuff to prepare" for repair, then the same in reverse. They called us every step of the way to let us know what they were doing and what was next and roughly when the next call should be. They said the only thing SHE would have connect to her if all went well would be an IV for fluids and meds, IV for measuring her blood pressure, chest tube for drainage, and simple nasal oxygen tube and a catheter. Since she is young they keep them sedated so they don't pull stuff out.
3rd- recovery will all depend on child. Our doc said 3 to 5 days stay. She was discharged in 24 hours, which I was told is unheard of. Surgery was at 7:30 am, at about 2 am they started weaning her off the sedation by 6 she was awake and walking to the bathroom (she didn't understand the catheter so they humored her), eating and by 10 am they removed her chest tube and was walking the ICU halls. PLEASE keep in mind this recovery time line is not the norm but the staff wished it was. They say 2 weeks recovery away from crowds, and 6 weeks total time for the ribs to heal.
I hope this helps.